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Sample records for bucket-handle meniscal tears

  1. MRI of meniscal bucket-handle tears

    Energy Technology Data Exchange (ETDEWEB)

    Magee, T.H.; Hinson, G.W. [Menorah Medical Center, Overland Park, KS (United States). Dept. of Radiology

    1998-09-01

    A meniscal bucket-handle tear is a tear with an attached fragment displaced from the meniscus of the knee joint. Low sensitivity of MRI for detection of bucket-handle tears (64% as compared with arthroscopy) has been reported previously. We report increased sensitivity for detecting bucket-handle tears with the use of coronal short tau inversion recovery (STIR) images. Results. By using four criteria for diagnosis of meniscal bucket-handle tears, our overall sensitivity compared with arthroscopy was 93% (28 of 30 meniscal bucket-handle tears seen at arthroscopy were detected by MRI). The meniscal fragment was well visualized in all 28 cases on coronal STIR images. The double posterior cruciate ligament sign was seen in 8 of 30 cases, the flipped meniscus was seen in 10 of 30 cases and a fragment in the intercondylar notch was seen in 18 of 30 cases. (orig.)

  2. Magnetic resonance imaging of meniscal bucket-handle tears

    International Nuclear Information System (INIS)

    Dfouni, N.; Garcia, J.; Kindynis, Ph.; Bosson, D.

    1997-01-01

    To define MR signs of meniscal bucket-handle tears and evaluate the diagnostic efficiency of this technique. Retrospective study of 30 patients with a meniscal bucket-handle tear and 30 with a different type of tear, all proven by arthroscopy. The following MR signs of a bucket-handle tear were evaluated: 'separate meniscal fragment, 'double posterior cruciate ligament', 'snake sign' and 'double anterior horn'. A correct diagnosis of a bucket-handle tear was only made in 18/30 of patients. Several of the MR signs were seen in the same patient in 17 cases. A double posterior cruciate ligament was present only in cases of medial meniscus tears. The 12 menisci without these signs, and therefore not diagnosed as bucket-handle tears, were all classified as meniscal tears on the basis of signal extending to the meniscal surface. Nine of these were not displaced into the inter-condylar notch at arthroscopy. The interobserver agreement was excellent: kappa 0.88. The diagnosis of a bucket-handle meniscal tear, if it is displaced, can be made when one or more of the four MR evaluated signs are present. Other forms of meniscal tears are only exceptionally diagnosed as bucket-handle tears. (authors)

  3. Bucket handle tears of the medial meniscus: meniscal intrusion rather than meniscal extrusion

    International Nuclear Information System (INIS)

    Schlossberg, S.; Umans, H.; Flusser, G.; DiFelice, G.S.; Lerer, D.B.

    2007-01-01

    To determine the frequency of medial meniscal extrusion (MME) versus ''medial meniscal intrusion'' in the setting of bucket handle tears. Images were evaluated for previously reported risk factors for MME, including: medial meniscal root tear, radial tear, degenerative joint disease and joint effusion. Forty-one consecutive cases of bucket handle tear of the medial meniscus were reviewed by consensus by two musculoskeletal radiologists. Imaging was performed using a 1.5 GE Signa MR unit. Patient age, gender, medial meniscal root integrity, MME, medial meniscal intrusion, degenerative joint disease, effusion and anterior cruciate ligament (ACL) tear were recorded. Thirteen females and 27 males (age 12-62 years, median=30 years) were affected; one had bucket handle tear of each knee. Effusion was small in 13, moderate in 9 and large in 18. Degenerative joint disease was mild in three, moderate in two and severe in one. 26 ACL tears included three partial and three chronic. Medial meniscal root tear was complete in one case and partial thickness in two. None of the 40 cases with an intact or partially torn medial meniscal root demonstrated MME. MME of 3.1 mm was seen in the only full-thickness medial meniscal root tear, along with chronic ACL tear, moderate degenerative joint disease and large effusion. Medial meniscal intrusion of the central bucket handle fragment into the intercondylar notch was present in all 41 cases. Given an intact medial meniscal root in the setting of a ''pure'' bucket handle tear, there is no MME. (orig.)

  4. MR imaging of meniscal bucket-handle tears: a review of signs and their relation to arthroscopic classification

    International Nuclear Information System (INIS)

    Aydingoez, Uestuen; Firat, Ahmet K.; Atay, Ahmet Oe.; Doral, Nedim M.

    2003-01-01

    Our objective was to review the MR imaging signs of meniscal bucket-handle tears and assess the relevance of these signs to the arthroscopic classification of displaced meniscal tears. Forty-five menisci in 42 patients who had a diagnosis of bucket-handle tear either on MR imaging or on subsequent arthroscopy (in which Dandy's classification of meniscal tears was used) were retrospectively analyzed for MR imaging findings of double posterior cruciate ligament (PCL), fragment within the intercondylar notch, absent bow tie, flipped meniscus, double-anterior horn, and disproportional posterior horn signs. Arthroscopy, which was considered as the gold standard, revealed 41 bucket-handle tears (either diagnosed or not diagnosed by MR imaging) in 38 patients (33 males, 5 females). There was a stastistically significant male preponderance for the occurrence of meniscal bucket-handle tears. Overall, sensitivity and positive predictive value of MR imaging for the detection of meniscal bucket-handle tears were calculated as 90%. Common MR imaging signs of meniscal bucket-handle tears in arthroscopically proven cases of such tears were the fragment in the notch and absent bow tie signs (98% frequency for each). Double-PCL, flipped meniscus, double-anterior horn, and disproportional posterior horn signs, however, were less common (32, 29, 29, and 27%, respectively). An arthroscopically proven bucket-handle tear was found in all patients who displayed at least three of the six MR imaging signs of meniscal bucket-handle tears. The presence of three or more MR imaging signs of meniscal bucket-handle tears is highly suggestive of this condition. (orig.)

  5. Bucket-handle meniscal tears of the knee: sensitivity and specificity of MRI signs

    International Nuclear Information System (INIS)

    Dorsay, Theodore A.; Helms, Clyde A.

    2003-01-01

    To determine the sensitivity and specificity of reported MRI signs in the evaluation of bucket-handle tears of the knee.Design and patients A retrospective analysis of 71 knee MR examinations that were read as displaying evidence of a bucket-handle or ''bucket-handle type'' tear was performed. We evaluated for the presence or absence of the absent bow tie sign, the coronal truncation sign, the double posterior cruciate ligament (PCL) sign, the anterior flipped fragment sign, and a fragment displaced into the intercondylar notch. Sensitivity and specificity were calculated relative to the gold standard of arthroscopy. Forty-three of 71 cases were surgically proven as bucket-handle tears. The absent bow tie sign demonstrated a sensitivity of 88.4%. The presence of at least one of the displaced fragment signs had a sensitivity of 90.7%. A finding of both the absent bow tie sign and one of the displaced fragment signs demonstrated a specificity of 85.7%. The double PCL sign demonstrated a specificity of 100%. The anterior flipped meniscus sign had a specificity of 89.7%. Bucket-handle tears of the menisci, reported in about 10% of most large series, have been described by several signs with MRI. This report gives the sensitivity and specificity of MRI for bucket-handle tears using each of these signs independently and in combination. MRI is shown to be very accurate for diagnosing bucket-handle tears when two or more of these signs coexist. (orig.)

  6. Hemi-bucket-handle tears of the meniscus: appearance on MRI and potential surgical implications

    Energy Technology Data Exchange (ETDEWEB)

    Engstrom, Bjorn I.; Vinson, Emily N.; Helms, Clyde A. [Duke University Medical Center, Department of Radiology, Box 3808, Durham, NC (United States); Taylor, Dean C.; Garrett, William E. [Duke University Medical Center, Department of Orthopaedics, Box 3810, Durham, NC (United States)

    2012-08-15

    To describe a type of meniscus flap tear resembling a bucket-handle tear, named a ''hemi-bucket-handle'' tear; to compare its imaging features with those of a typical bucket-handle tear; and to discuss the potential therapeutic implications of distinguishing these two types of tears. Five knee MR examinations were encountered with a type of meniscus tear consisting of a flap of tissue from the undersurface of the meniscus displaced toward the intercondylar notch. A retrospective analysis of 100 MR examinations prospectively interpreted as having bucket-handle type tears yielded 10 additional cases with this type of tear. Cases of hemi-bucket-handle tears were reviewed for tear location and orientation, appearance of the superior articular surface of the meniscus, presence and location of displaced meniscal tissue, and presence of several classic signs of bucket-handle tears. A total of 15/15 tears involved the medial meniscus, had tissue displaced toward the notch, and were mainly horizontal in orientation. The superior surface was intact in 11/15 (73.3%). In 1/15 (6.7%) there was an absent-bow-tie sign; 6/15 (40%) had a double-PCL sign; 14/15 (93.3%) had a double-anterior horn sign. We describe a type of undersurface flap tear, named a hemi-bucket-handle tear, which resembles a bucket-handle tear. Surgeons at our institution feel this tear would likely not heal if repaired given its predominantly horizontal orientation, and additionally speculate the tear could be overlooked at arthroscopy. Thus, we feel it is important to distinguish this type of tear from the typical bucket-handle tear. (orig.)

  7. Hemi-bucket-handle tears of the meniscus: appearance on MRI and potential surgical implications

    International Nuclear Information System (INIS)

    Engstrom, Bjorn I.; Vinson, Emily N.; Helms, Clyde A.; Taylor, Dean C.; Garrett, William E.

    2012-01-01

    To describe a type of meniscus flap tear resembling a bucket-handle tear, named a ''hemi-bucket-handle'' tear; to compare its imaging features with those of a typical bucket-handle tear; and to discuss the potential therapeutic implications of distinguishing these two types of tears. Five knee MR examinations were encountered with a type of meniscus tear consisting of a flap of tissue from the undersurface of the meniscus displaced toward the intercondylar notch. A retrospective analysis of 100 MR examinations prospectively interpreted as having bucket-handle type tears yielded 10 additional cases with this type of tear. Cases of hemi-bucket-handle tears were reviewed for tear location and orientation, appearance of the superior articular surface of the meniscus, presence and location of displaced meniscal tissue, and presence of several classic signs of bucket-handle tears. A total of 15/15 tears involved the medial meniscus, had tissue displaced toward the notch, and were mainly horizontal in orientation. The superior surface was intact in 11/15 (73.3%). In 1/15 (6.7%) there was an absent-bow-tie sign; 6/15 (40%) had a double-PCL sign; 14/15 (93.3%) had a double-anterior horn sign. We describe a type of undersurface flap tear, named a hemi-bucket-handle tear, which resembles a bucket-handle tear. Surgeons at our institution feel this tear would likely not heal if repaired given its predominantly horizontal orientation, and additionally speculate the tear could be overlooked at arthroscopy. Thus, we feel it is important to distinguish this type of tear from the typical bucket-handle tear. (orig.)

  8. Diagnostic value of self-reported mechanical symptoms for diagnosing large meniscal tears in patients aged 40 years or older with meniscal tears

    DEFF Research Database (Denmark)

    Pihl, Kenneth; Englund, Martin; Lohmander, Stefan

    2017-01-01

    Purpose: Meniscal tears, which are longitudinal-vertical tears (e.g. bucket-handle tears) and/or involve all three meniscal sub regions (anterior horn, body and posterior horn), are typically large and assumed to cause patient perceived mechanical knee symptoms (knee grinding or clicking and knee...... catching or locking). However, whether the presence of such mechanical symptoms is useful for diagnosing these forms of meniscus tears is unknown. Therefore, we investigated the diagnostic values of having mechanical symptoms in diagnosing a bucket-handle tear and/or a tear involving all three meniscal sub...... regions in middle-aged and older patients undergoing arthroscopic meniscal surgery. Methods: This study is a secondary analysis of Pihl et al. OARSI 2017. The study included patients aged 40 years or older undergoing surgery for a meniscal tear from Knee Arthroscopy Cohort Southern Denmark (KACS...

  9. Use of the V-sign in the diagnosis of bucket-handle meniscal tear of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Nisha [Radiology Associates of Tampa, Tampa, FL (United States); Patel, Yogita [Jamaica Hospital Medical Center, Jamaica, NY (United States); Opsha, Oleg; Eisemon, Eric; Beltran, Javier [Maimonides Medical Center, Brooklyn, NY (United States); Chen, Qi [SUNY Downstate Medical Center, Department of Radiology, Brooklyn, NY (United States); Owen, Joshua [Saint Louis University School of Medicine, Department of Radiology, St. Louis, MO (United States); Fogel, Joshua [Brooklyn College of the City University of New York, Department of Economics, Brooklyn, NY (United States)

    2012-03-15

    Bucket-handle tear is a displaced vertical longitudinal tear of the meniscus. Several signs of the tear have been described on MRI but none in the axial plane. We propose to describe such a sign named the V-sign that is seen at the junction of the displaced fragment and the meniscus, which is in place. MRI imaging of 25 surgically proven bucket-handle tears was reviewed for presence of the V-sign. Two control groups, one with normal menisci (n = 75) and one with surgically proven non-bucket-handle tears (n = 25), were also evaluated. Comparisons for presence or absence of the V-sign were performed among the three groups, and also for other commonly associated signs such as double PCL sign, double delta sign, and presence of ACL tear. Also, sensitivity, specificity, and positive and negative predictive values were calculated. Among those with bucket-handle tear, 72% demonstrated the V-sign while no participant in either control group had the V-sign (P {<=} 0.001). The V-sign occurred in 38% of those with double PCL sign, 55.6% with ACL tear, and 66.7% with double delta sign. The V-sign had higher sensitivity and negative predictive values than other signs related to bucket-handle tear. The V-sign, when seen on an axial plane image, is highly suggestive of bucket-handle tear. Our data suggest the benefit of using the V-sign for detecting bucket-handle tears, perhaps even above other commonly used approaches. (orig.)

  10. Use of the V-sign in the diagnosis of bucket-handle meniscal tear of the knee

    International Nuclear Information System (INIS)

    Rao, Nisha; Patel, Yogita; Opsha, Oleg; Eisemon, Eric; Beltran, Javier; Chen, Qi; Owen, Joshua; Fogel, Joshua

    2012-01-01

    Bucket-handle tear is a displaced vertical longitudinal tear of the meniscus. Several signs of the tear have been described on MRI but none in the axial plane. We propose to describe such a sign named the V-sign that is seen at the junction of the displaced fragment and the meniscus, which is in place. MRI imaging of 25 surgically proven bucket-handle tears was reviewed for presence of the V-sign. Two control groups, one with normal menisci (n = 75) and one with surgically proven non-bucket-handle tears (n = 25), were also evaluated. Comparisons for presence or absence of the V-sign were performed among the three groups, and also for other commonly associated signs such as double PCL sign, double delta sign, and presence of ACL tear. Also, sensitivity, specificity, and positive and negative predictive values were calculated. Among those with bucket-handle tear, 72% demonstrated the V-sign while no participant in either control group had the V-sign (P ≤ 0.001). The V-sign occurred in 38% of those with double PCL sign, 55.6% with ACL tear, and 66.7% with double delta sign. The V-sign had higher sensitivity and negative predictive values than other signs related to bucket-handle tear. The V-sign, when seen on an axial plane image, is highly suggestive of bucket-handle tear. Our data suggest the benefit of using the V-sign for detecting bucket-handle tears, perhaps even above other commonly used approaches. (orig.)

  11. Role of MRI in predicting meniscal tear reparability

    Energy Technology Data Exchange (ETDEWEB)

    Felisaz, Paolo Florent [Universita degli Studi di Pavia, Pavia (Italy); Fondazione IRCCS Policlinico San Matteo, Istituto di Radiologia, Pavia (Italy); Alessandrino, Francesco; Perelli, Simone [Universita degli Studi di Pavia, Pavia (Italy); Zanon, Giacomo; Benazzo, Francesco [Fondazione IRCCS Policlinico San Matteo, Clinica Ortopedica e Traumatologica, Pavia (Italy); Calliada, Fabrizio; Sammarchi, Luigi [Fondazione IRCCS Policlinico San Matteo Radiologia, Diagnostica per Immagini-Istituto di Radiologia, Pavia (Italy)

    2017-10-15

    To elucidate the role of MRI in predicting meniscal tear reparability according to tear type and location in relation to vascular zones. In this retrospective study, two readers evaluated 79 pre-surgical MRIs of meniscal tears arthroscopically treated with meniscectomy or meniscal repair. Tears were classified according to type into vertical, horizontal, radial, complex, flaps and bucket handle and were considered reparable if the distance measured from the tear to the menisco-capsular junction was less than or equal to 5 mm. Predictions were compared with the surgical procedure performed in arthroscopy. We assessed the diagnostic performance of MRI, agreement between MRI and arthroscopy, and interrater agreement. Then, we conducted an ROC analysis on the distances measured by the first reader and built a multivariate logistic regression model. MRI had a sensitivity, specificity, PPV, NPV and accuracy, respectively, of 85%, 79%, 86%, 76% and 83% in predicting meniscal tear reparability. Correct predictions for the specific tear pattern were 76% for vertical, 84% for horizontal, 88% for radial, 86% for complex, 84% for flaps and 86% for bucket handle. Agreement between the two readers' predictions and arthroscopy was good (k = 0.65 and 0.61, respectively). Inter-rater agreement was almost excellent (k = 0.79). The ROC analysis revealed sensitivity and specificity of 73% and 83% with a cutoff value of <4 mm (p < 0.001). Anterior cruciate ligament injury and medial meniscal tear increased the likelihood of meniscal tear reparability. MRI can be a reliable and accurate tool to predict the reparability of meniscal tears, with higher prediction rates for bucket-handle tears. (orig.)

  12. The value of the absent bow tie sign in MRI of bucket-handle tears

    International Nuclear Information System (INIS)

    Watt, Andrew J.B.; Halliday, Tonya; Raby, Nigel

    2000-01-01

    AIM: To assess the accuracy of the absent bow tie sign in diagnosing bucket handle meniscal tears (BHT) of the knee menisci. MATERIALS AND METHODS: During a 3-year period, we correlated the MRI and arthroscopic findings and the presence of the various signs. One hundred and seven knees were reviewed: 74 where either MRI or arthroscopy had identified a BHT and 33 which were either normal (31), or a simple tear was identified (2). All cases were reviewed by a single radiologist with a musculoskeletal interest blinded to the original results. Each was assessed for the presence of (1) a central meniscal fragment, (2) the double posterior cruciate ligament (PCL) sign, (3) the bow tie sign and (4) the contribution of a 3D-volume sequence. RESULTS: Optimal results were obtained using standard sequences and a 3D-volume sequence, giving a sensitivity of 74% and positive predictive value of 89%. The bow tie sign gave a sensitivity of 71% and positive predictive value of 76%, significantly less than previous reports. The 18 BHTs diagnosed by arthroscopy but missed by MRI showed other abnormal findings at MRI and were not reported as normal. CONCLUSION: We were not able to reproduce the previously reported high sensitivity and specificity of the absent bow tie sign. Despite optimization of all factors, the accurate diagnosis of a bucket handle tear remains difficult, and is most reliably made by identifying a central meniscal fragment, rather than relying on secondary signs such as the absent bow tie sign. Watt, A.J.B. (2000)

  13. MR imaging-based diagnosis and classification of meniscal tears.

    Science.gov (United States)

    Nguyen, Jie C; De Smet, Arthur A; Graf, Ben K; Rosas, Humberto G

    2014-01-01

    Magnetic resonance (MR) imaging is currently the modality of choice for detecting meniscal injuries and planning subsequent treatment. A thorough understanding of the imaging protocols, normal meniscal anatomy, surrounding anatomic structures, and anatomic variants and pitfalls is critical to ensure diagnostic accuracy and prevent unnecessary surgery. High-spatial-resolution imaging of the meniscus can be performed using fast spin-echo and three-dimensional MR imaging sequences. Normal anatomic structures that can mimic a tear include the meniscal ligament, meniscofemoral ligaments, popliteomeniscal fascicles, and meniscomeniscal ligament. Anatomic variants and pitfalls that can mimic a tear include discoid meniscus, meniscal flounce, a meniscal ossicle, and chondrocalcinosis. When a meniscal tear is identified, accurate description and classification of the tear pattern can guide the referring clinician in patient education and surgical planning. For example, longitudinal tears are often amenable to repair, whereas horizontal and radial tears may require partial meniscectomy. Tear patterns include horizontal, longitudinal, radial, root, complex, displaced, and bucket-handle tears. Occasionally, meniscal tears can be difficult to detect at imaging; however, secondary indirect signs, such as a parameniscal cyst, meniscal extrusion, or linear subchondral bone marrow edema, should increase the radiologist's suspicion for an underlying tear. Awareness of common diagnostic errors can ensure accurate diagnosis of meniscal tears. Online supplemental material is available for this article. ©RSNA, 2014.

  14. MRI imaging of displaced meniscal tears: Report of a case highlighting new potential pitfalls of the MRI signs

    International Nuclear Information System (INIS)

    Prasad, Abhishek; Brar, Rahat; Rana, Shaleen

    2014-01-01

    Magnetic resonance imaging (MRI) has been found to be an excellent imaging tool for meniscal injuries. Various MRI signs have been described to detect displaced meniscal injuries, specifically the bucket-handle tears. Although these signs are quite helpful in diagnosing meniscal tears, various pitfalls have also been reported for these signs. Double anterior cruciate ligament (ACL) sign refers to presence of a linear hypointense soft tissue anterior to the ACL, which represented the flipped bucket-handle tear of the meniscus. Disproportional posterior horn and flipped meniscus signs represent asymmetrically thickened horns of the menisci due to overlying displaced meniscal fragments. We report a case wherein MRI of the knee showed tear and displacement of the medial patellofemoral ligament (MPFL) and vastus medialis complex, medial collateral ligament (MCL), and posterior cruciate ligament (PCL) mimicking these signs. To our knowledge, internally displaced MPFL and MCLs have not been described as mimics for displaced meniscal fragments

  15. Anamnestic prediction of bucket handle compared to other tear patterns of the medial meniscus in stable knees.

    Science.gov (United States)

    Haviv, Barak; Bronak, Shlomo; Kosashvili, Yona; Thein, Rafael

    2016-12-01

    The aim of this study was to analyze and compare the preoperative anamnestic details between patients with an arthroscopic diagnosis of bucket handle and other tear patterns of the medial meniscus in stable knees. A total of 204 patients (mean age 49.3 ± 13 years) were included in the study. The mean age was 49.3 ± 13 years. The study group included 65 patients (63 males, 2 females) with an arthroscopic diagnosis of bucket handle tear and the control group included 139 patients (90 males, 49 females) with non-bucket handle tear patterns. The preoperative clinical assessments of the two groups were analyzed retrospectively. Anamnestic prediction for the diagnosis of a bucket handle tear was based upon various medical history parameters. Multivariate logistic regression was carried out to identify independent anamnestic factors for predicting isolated bucket handle tears of the medial meniscus compared to non-bucket handle tears. Analysis of the multivariate logistic regression yielded 3 statistically significant independent anamnestic risk factors for predicting isolated bucket handle tears of the medial meniscus: male gender (OR, 9.7; 95% CI, 1.1-37.6), locking events (OR, 4.6; 95% CI, 1.8-11.3) and pain in extension (OR, 6.9; 95% CI, 2.5-23.7). Other preoperative variables such as age, BMI, activity level, comorbidities, duration of symptoms, pain location, preceding injury and its mechanism had no significant effect on tear pattern. Preoperative strong clues for bucket handle tears of the medial meniscus in stable knees are male gender, locking events and limitation in extension. Level III, Diagnostic study. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  16. Bucket-handle tear of posterior uterine cervical lip in a second ...

    African Journals Online (AJOL)

    A bucket-handle tear is a laceration of either the anterior lip or the posterior lip of the cervix so that it hangs like the handle of a bucket.These cervical injuries are more common in term deliveries and are associated with various risks factors, including cervical cerclage, induction of labour, young maternal age, assisted ...

  17. MRI findings in bucket-handle tears of the triangular fibrocartilage complex

    International Nuclear Information System (INIS)

    Jose, Jean; Arizpe, Azael; Chen, David; Barrera, Carlos M.; Ezuddin, Nisreen Shabbir

    2018-01-01

    The triangular fibrocartilage complex (TFCC) is an intricate ligamentous and cartilaginous structure that helps transmit axial load across the wrist, and provide stability to the ulnocarpal and distal radioulnar joints (DRUJ). Because the blood supply to the TFCC varies depending on location, certain types of tears are more amenable to surgical repair than others. Since Palmer proposed his classification system of TFCC tears in 1989, only 1 case of a ''bucket-handle'' type tear has been reported. In this article, we describe two new cases of bucket-handle tears of the TFCC. In both cases, the torn fragment was displaced into a previously undescribed location (intra-articular DRUJ and prestyloid recess). Because this type of injury pattern has not been previously well characterized in the literature and such cases rarely reported, MRI findings have not been fully described and its implications on clinical management have largely yet to be determined. (orig.)

  18. MRI findings in bucket-handle tears of the triangular fibrocartilage complex

    Energy Technology Data Exchange (ETDEWEB)

    Jose, Jean [University of Miami Miller School of Medicine, Department of Radiology, Jackson Memorial Hospital, Miami, FL (United States); University of Miami Miller School of Medicine, Department of Orthopedic Surgery, Uhealth Sports Medicine Institute, Miami, FL (United States); Arizpe, Azael; Chen, David [University of Miami Miller School of Medicine, Department of Orthopedic Surgery, Jackson Memorial Hospital, Miami, FL (United States); Barrera, Carlos M.; Ezuddin, Nisreen Shabbir [University of Miami, Miller School of Medicine, Coral Gables, FL (United States)

    2018-03-15

    The triangular fibrocartilage complex (TFCC) is an intricate ligamentous and cartilaginous structure that helps transmit axial load across the wrist, and provide stability to the ulnocarpal and distal radioulnar joints (DRUJ). Because the blood supply to the TFCC varies depending on location, certain types of tears are more amenable to surgical repair than others. Since Palmer proposed his classification system of TFCC tears in 1989, only 1 case of a ''bucket-handle'' type tear has been reported. In this article, we describe two new cases of bucket-handle tears of the TFCC. In both cases, the torn fragment was displaced into a previously undescribed location (intra-articular DRUJ and prestyloid recess). Because this type of injury pattern has not been previously well characterized in the literature and such cases rarely reported, MRI findings have not been fully described and its implications on clinical management have largely yet to be determined. (orig.)

  19. A Contact Pressure Analysis Comparing an All-Inside and Inside-Out Surgical Repair Technique for Bucket-Handle Medial Meniscus Tears.

    Science.gov (United States)

    Marchetti, Daniel Cole; Phelps, Brian M; Dahl, Kimi D; Slette, Erik L; Mikula, Jacob D; Dornan, Grant J; Bucci, Gabriella; Turnbull, Travis Lee; Singleton, Steven B

    2017-10-01

    To directly compare effectiveness of the inside-out and all-inside medial meniscal repair techniques in restoring native contact area and contact pressure across the medial tibial plateau at multiple knee flexion angles. Twelve male, nonpaired (n = 12), fresh-frozen human cadaveric knees underwent a series of 5 consecutive states: (1) intact medial meniscus, (2) MCL tear and repair, (3) simulated bucket-handle longitudinal tear of the medial meniscus, (4) inside-out meniscal repair, and (5) all-inside meniscal repair. Knees were loaded with a 1,000-N axial compressive force at 5 knee flexion angles (0°, 30°, 45°, 60°, 90°), and contact area, mean contact pressure, and peak contact pressure were calculated using thin film pressure sensors. No significant differences were observed between the inside-out and all-inside repair techniques at any flexion angle for contact area, mean contact pressure, and peak contact pressure (all P > .791). Compared with the torn meniscus state, inside-out and all-inside repair techniques resulted in increased contact area at all flexion angles (all P contact pressure at all flexion angles (all P contact pressure at all flexion angles (all P contact area and peak contact pressure between the intact state and inside-out technique at angles ≥45° (all P contact area at 60° and 90° and peak contact pressure at 90° (both P contact area, mean contact pressure, and peak contact pressure over the tested flexion angles ranged from 498 to 561 mm 2 , 786 to 997 N/mm 2 , and 1,990 to 2,215 N/mm 2 , respectively. Contact area, mean contact pressure, and peak contact pressure were not significantly different between the all-inside and inside-out repair techniques at any tested flexion angle. Both techniques adequately restored native meniscus biomechanics near an intact level. An all-inside repair technique provided similar, native-state-restoring contact mechanics compared with an inside-out repair technique for the treatment of

  20. MRI of displaced meniscal fragments

    International Nuclear Information System (INIS)

    Dunoski, Brian; Zbojniewicz, Andrew M.; Laor, Tal

    2012-01-01

    A torn meniscus frequently requires surgical fixation or debridement as definitive treatment. Meniscal tears with associated fragment displacement, such as bucket handle and flap tears, can be difficult to recognize and accurately describe on MRI, and displaced fragments can be challenging to identify at surgery. A displaced meniscal fragment can be obscured by synovium or be in a location not usually evaluated at arthroscopy. We present a pictorial essay of meniscal tears with displaced fragments in patients referred to a pediatric hospital in order to increase recognition and accurate interpretation by the radiologist, who in turn can help assist the surgeon in planning appropriate therapy. (orig.)

  1. MRI of displaced meniscal fragments

    Energy Technology Data Exchange (ETDEWEB)

    Dunoski, Brian [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); Children' s Hospital of Michigan, Department of Radiology, Detroit, MI (United States); Zbojniewicz, Andrew M.; Laor, Tal [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States)

    2012-01-15

    A torn meniscus frequently requires surgical fixation or debridement as definitive treatment. Meniscal tears with associated fragment displacement, such as bucket handle and flap tears, can be difficult to recognize and accurately describe on MRI, and displaced fragments can be challenging to identify at surgery. A displaced meniscal fragment can be obscured by synovium or be in a location not usually evaluated at arthroscopy. We present a pictorial essay of meniscal tears with displaced fragments in patients referred to a pediatric hospital in order to increase recognition and accurate interpretation by the radiologist, who in turn can help assist the surgeon in planning appropriate therapy. (orig.)

  2. Inferomedial displacement of the meniscal free fragment: MR findings

    International Nuclear Information System (INIS)

    Sorrentino, Fortunato; Iovane, Angelo; Nicosia, Antonio; Candela, Fabrizio; Midiri, Massimo; De Maria, Marcello

    2005-01-01

    Purpose. To define the accuracy of Magnetic Resonance (MR) in the diagnosis of inferomedial displacement of the meniscal fragments. Materials and methods. The MR examinations of the knee performed between December 2002 and April 2004 on 676 patients (mean age 32 years) with knee trauma and subsequently subjected to arthroscopy were retrospectively reviewed to assess the presence of bucket-handle meniscal tear and inferomedial displacement of the meniscal free fragment. The MR examinations were performed using a superconductive 0.5 T MR unit with a transmitting/receiving coil dedicated for the extremities. The MR images were acquired with SE T1 and GE T2 sequences in the sagittal, coronal and axial planes with 3 mm thickness and 1 mm gap. The images were independently reviewed by two authors blinded to the arthroscopy findings. In case of disagreement, a third author, unaware of the arthroscopic findings, gave his judgment. Results. On MR images a bucket-handle meniscal tear was identified in 54/676 patients. In 6 out of 54 patients, an inferomedial meniscal fragment displacement of the medical meniscus with associated inflammatory synovial reaction around the distal insertion of the medial homolateral collateral ligament was detected. All cases were confirmed by arthroscopy and no statistical differences between the two authors were observed. Conclusions. MR allows the detection of the inferomedial meniscal fragment displacement and a more correct planning of arthroscopy with a strong reduction of repeat interventions [it

  3. Painful locking of the knee due to bucket handle tear of

    Directory of Open Access Journals (Sweden)

    HE Rui

    2011-04-01

    Full Text Available 【Abstract】 A case of swelling and anterior painful knee due to tear of mediopatellar plica is reported. The patient also felt clunk of the patellofemoral joint and knee locking. Under arthroscopic examination, a thick and fibrous plica was found medial to patellar, and a bucket tear along the plica from medial patellar retinaculum to infrapatellar fat pad. Polarized microscopic examination showed collagen fiber fragment and loss of light reflecting property. Neuroimmunohistology suggested up-regulation of synovial plica innervation in the area around the crack. This may be related to the pain. The bucket tear of mediopatellar plicacaused pain and lock of knee are more common than previously reported. Key words: Knee injuries; Arthroscopy; Patellofemoral joint

  4. Reversed double PCL sign: unusual location of a meniscal fragment of the knee observed by MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Niitsu, M.; Itai, Y. [Dept. of Radiology, Inst. of Clinical Medicine, Univ. of Tsukuba, Ibaraki (Japan); Ikeda, K. [Inst. of Clinical Medicine, Univ. of Tsukuba, Ibaraki (Japan)

    2003-12-01

    A 36-year-old woman with tears of the anterior cruciate ligament and medial meniscus received a meniscectomy. The MR images obtained prior to the partial meniscectomy showed a bucket-handle meniscal tear with centrally displaced fragment lying anterior to the posterior cruciate ligament (PCL), representing a ''double PCL sign''; however, after the meniscectomy, MR images demonstrated a fragment in the space posterior to the PCL where no structure is generally recognized except for the ligament of wrisberg. This article reports a ''reversed'' double PCL sign, caused by inadequate surgical clearance of a bucket-handle tear of the medial meniscus. (orig.)

  5. MRI diagnosis of meniscal tears

    International Nuclear Information System (INIS)

    Kuga, Naoyuki; Oh, Toshihiro

    1996-01-01

    We studied the accuracy of magnetic resonance imaging (MRI) of the knee in fifty-six patients who were also examined arthroscopically. The accuracy, sensitivity, and specificity were 96%, 100%, and 95% for medial meniscal tears, and 91%, 67%, and 100% for lateral meniscal tears respectively. Two MRIs of the medial meniscus were false-positives. These MRI findings were both meniscocapsular separation of the medial meniscus, but the arthroscopic findings were normal. One case was an ACL injury and the other PCL and MCL injury. Hemorrhage and edema of the medial capsule caused by valgus stress at injury may look like a meniscal pseudo-tear on MRI. Five MRIs of the lateral meniscus were false-negatives. All menisci showed normal signal and shape on MRI but traumatic and stable tears of the lateral meniscus were identified arthroscopically. All were associated with ACL tears and lateral condylar bone bruise. The traumatic and stable tear of the meniscus tended to be overlooked on MRI because a meniscus without degeneration shows a normal signal. (author)

  6. Detecting meniscal tears in primary care

    NARCIS (Netherlands)

    Snoeker, B.A.M.

    2017-01-01

    Although meniscal tears are a very common phenomenon uncertainty exists about the diagnosis and treatment of meniscal tears in primary care. This thesis aims to provide evidence for general practitioners and physical therapists regarding the diagnosis and management of patients with a suspected

  7. MR imaging of meniscal tears: correlation with history of trauma

    International Nuclear Information System (INIS)

    Choi, Jong Cheul; Yang, Seoung Oh; Choi, Sun Seob; Son, Seok Hyun; Lee, Yung Il; Chung, Duck Hwan; Kim, Kyung Taek; Sohn, Sung Keun; Lee, Jung Yoon

    1994-01-01

    The medial meniscus is injured much more than the lateral meniscus. Because the medial meniscus is much larger in diameter, is thinner in its periphery and narrower in body than the lateral meniscus, and dose not attach to either cruciate ligament. We evaluated correlations with sites of tear and history of trauma. We reviewed retrospectively in 43 patients with meniscal tears on MR(51 cases) and correlated them with history of trauma. The most common site of injury was the posterior horn of the medial meniscuc(32/51), but high incidence of lateral meniscal tear compared with previous reports was seen. In the cases which had history of trauma, the posterior horn of medial meniscus was most commonly injured(26/34) and 5 meniscal tears were combined with meniscal tear in the other site. The tear in the anterior horn of the medial meniscus was seen only in a patient which had history of trauma and combined with meniscal tear in the other site. But in the meniscal tears without definite history of trauma, the incidence of meniscal tear was different from the meniscal tear with history of trauma. The incidence of lateral meniscal tear(11/17) was higher than medial meniscal tear and the posterior horn of lateral meniscus was commonly injured. We concluded that the medial meniscus was commonly injured, especially posterior horn, but in the cases which had no definite history of trauma, the lateral meniscus was commonly injured. An awareness of prevalent site of meniscal injuries may be helpful in the diagnostic interpretation of MR imaging of knee

  8. Posterior horn medial meniscal root tear: the prequel

    Energy Technology Data Exchange (ETDEWEB)

    Umans, H. [Albert Einstein College of Medicine, Bronx, NY (United States); Lenox Hill Radiology and Imaging Associates, New York, NY (United States); Morrison, W. [Thomas Jefferson University Hospital, Philadelphia, PA (United States); DiFelice, G.S. [Hospital for Special Surgery, New York, NY (United States); Vaidya, N. [Crystal Run Healthcare, Middletown, NY (United States); Winalski, C.S. [Cleveland Clinic, Imaging Institute, Department of Biomedical Engineering, Lerner Research Institute, Cleveland, OH (United States)

    2014-06-15

    To determine whether subarticular marrow changes deep to the posterior horn medial meniscal root anchor might predict subsequent medial meniscal root tear. Fifteen patients with MR-diagnosed posterior horn medial meniscal root (PHMMR) tear and a knee MRI antecedent to the tear were identified at three imaging centers over a 7-year period. The pre- and post-tear MR images were evaluated for marrow signal changes deep to the root anchor, meniscal root signal intensity, medial compartment articular cartilage thinning, and meniscal body extrusion. Images of 29 age- and gender-matched individuals with two MRIs of the same knee were reviewed as a control group. MRI in 11 of 15 (73 %) cases with subsequent PHMMR tear demonstrated linear subcortical marrow edema deep to the meniscal root anchor on the antecedent MRI compared to only 1 of 29 (3 %) non-tear controls (p < 0.0001). The abnormal signal resolved on post-tear MRI in all but two patients. Cyst-like changes deep to the PHMMR were present on initial MRI in three of 15 (23 %) cases and three of 29 (10 %) controls, persisting in all but one case on follow-up imaging. The PHMMR was gray on the initial MRI in seven of 15 (47 %) of cases that developed tears compared to four of 29 (14 %) controls (p < 0.0001). There was medial meniscal extrusion (MME) prior to tear in two of 15 (13 %) patients and in ten of 15 (67 %) patients after PHMMR failure. In the control group, MME was present in one (3 %) and three (10 %) of 29 subjects on the initial and follow-up MRIs, respectively. Articular cartilage loss was noted in two of 15 (15 %) cases before tear and nine of 15 (69 %) on follow-up imaging, as compared to one (3 %) and four (14 %) of 29 subjects in the control group. Subcortical marrow edema deep to the PHMMR may result from abnormal stresses and thus be a harbinger of meniscal root failure. This hypothesis is supported by resolution of these marrow signal changes after root tear. Following tear, extrusion of the

  9. Chondral Injuries and Irreparable Meniscal Tears Among Adolescents With Anterior Cruciate Ligament or Meniscal Tears Are More Common in Patients With Public Insurance.

    Science.gov (United States)

    Williams, Ariel A; Mancini, Nickolas S; Solomito, Matthew J; Nissen, Carl W; Milewski, Matthew D

    2017-07-01

    Access to health care services is a critical component of health care reform and may differ among patients with different types of insurance. Hypothesis/Purpose: The purpose was to compare adolescents with private and public insurance undergoing surgery for anterior cruciate ligament (ACL) and/or meniscal tears. We hypothesized that patients with public insurance would have a delayed presentation from the time of injury and therefore would have a higher incidence of chondral injuries and irreparable meniscal tears and lower preoperative International Knee Documentation Committee (IKDC) scores than patients with private insurance. Cross-sectional study; Level of evidence, 3. This was a retrospective study of patients under 21 years of age undergoing ACL reconstruction and/or meniscal repair or debridement from January 2013 to March 2016 at a single pediatric sports medicine center. Patients were identified by a search of Current Procedural Terminology (CPT) codes. A chart review was performed for insurance type; preoperative diagnosis; date of injury, initial office visit, and surgery; preoperative IKDC score; intraoperative findings; and procedures. The study group consisted of 119 patients (mean age, 15.0 ± 1.7 years). Forty-one percent of patients had private insurance, while 59% had public insurance. There were 27 patients with isolated meniscal tears, 59 with combined meniscal and ACL tears, and 33 with isolated ACL tears. The mean time from injury to presentation was 56 days (range, 0-457 days) in patients with private insurance and 136 days (range, 0-1120 days) in patients with public insurance ( P = .02). Surgery occurred, on average, 35 days after the initial office visit in both groups. The mean preoperative IKDC score was 53 in both groups. Patients with meniscal tears with public insurance were more likely to require meniscal debridement than patients with private insurance (risk ratio [RR], 2.3; 95% CI, 1.7-3.1; P = .02). Patients with public insurance

  10. T-Fix endoscopic meniscal repair: technique and approach to different types of tears.

    Science.gov (United States)

    Barrett, G R; Richardson, K; Koenig, V

    1995-04-01

    Endoscopic meniscus repair using the T-Fix suture device (Acufex Microsurgical, Inc, Mansfield, MA) allows ease of suture placement for meniscus stability without the problems associated with ancillary incisions such as neurovascular compromise. It is ideal for the central posterior horn tears that are difficult using conventional techniques. Vertical tears, bucket handle tears, flap tears, and horizontal tears can be approached using a temporary "anchor stitch" to stabilize the meniscus before T-Fix repair. The basic method of repair and our approach to these different types of tears is presented.

  11. Meniscal tears, repairs and replacement: their relevance to osteoarthritis of the knee.

    Science.gov (United States)

    McDermott, Ian

    2011-04-01

    The menisci of the knee are important load sharers and shock absorbers in the joint. Meniscal tears are common, and whenever possible meniscal tears should be surgically repaired. Meniscectomy leads to a significant increased risk of osteoarthritis, and various options now exist for replacing missing menisci, including the use of meniscal scaffolds or the replacement of the entire meniscus by meniscal allograft transplantation. The field of meniscal surgery continues to develop apace, and the future may lie in growing new menisci by tissue engineering techniques.

  12. The role of an axial MR scan on the diagnosis a meniscal tear of the knee joint

    International Nuclear Information System (INIS)

    Yeom, Suk Keu; Kim, Baek Hyun; Hong, Suk Joo; Seol, Hae Young

    2007-01-01

    To evaluate the role of standard axial MR images for the diagnosis for meniscal tears of the knee. Forty-five patients with a prior MRI examination that underwent arthroscopic surgery of the knee due to clinical impression of a meniscal tear were included in the study group. The sequence for meniscal evaluation was an axial fat-saturated proton density-weighted image with a 4 mm slice thickness. Axial MR images were independently reviewed by two radiologists and were compared with findings of arthroscopy. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the axial MR scan for the diagnosis of the meniscal tear were calculated. A total 90 menisci of 45 patients were evaluated in the axial MR scans. Forty-two patients had meniscal tears, and two of the patients had tears in both menisci; thus, a total of 44 meniscal tears were found by arthroscopy. For meniscal tears, the sensitivity of the axial plane was 76.2%, the specificity was 89.1% and the accuracy was 81.1%. False negative meniscal tears were seen in 12 cases and false positive meniscal tears were seen in 5 cases on the axial MR images. In standard knee MRI examinations, axial images may be valuable for the detection and localization of meniscal tears

  13. MRI diagnosis in meniscal tears: a Meta analysis

    International Nuclear Information System (INIS)

    Liu Xiaosheng; Xu Jianrong; Hua Jia; Wang Baisong

    2007-01-01

    Objective: To perform a Meta-analysis to evaluate the overall diagnostic value of magnetic resonance imaging (MRI) in patients with suspected meniscal tears. Methods: All the papers concerning the diagnosis of meniscal tears using MRI in both English and Chinese published from 1998 to 2004 had been searched and reviewed, and the studies with the arthroscopy as the gold standard were adopted as eligible. Statistical analysis was performed employing SAS 8.0. Heterogeneity of the included articles was tested, which was used to select proper effect model to calculate pooled weighted sensitivity, specificity and accuracy. Summary receiver operating characteristic (SROC) analyses were performed for tears of both menisci. Finally, subgroup analysis on magnetic field strength was performed. Results: Totally 11 studies were met the inclusion criteria with a total of 1221 patients. The pooled indexes of diagnostic performance and SROC demonstrated a high discriminatory power for detecting tears of the medial and lateral menisci. The value of TPR * for medial and lateral menisci showed no significant difference (0.90, 0.86, respectively, Z=0.11, P>0.05). Subgroup analysis demonstrated no statistically significant difference on diagnostic performance for various magnetic field strength (P>0.05). Conclusion: MRI is a highly accurate diagnostic tool for detecting tears of the medial and lateral menisci. At present, there is no evidence to ascertain that higher magnetic field strength improves discriminatory power for meniscal tears. (authors)

  14. MR diagnosis of meniscal tears of the knee: analysis of error patterns.

    Science.gov (United States)

    Van Dyck, Pieter; Gielen, Jan; D'Anvers, Jan; Vanhoenacker, Filip; Dossche, Lieven; Van Gestel, Jozef; Parizel, Paul M

    2007-11-01

    Despite high accuracy of magnetic resonance imaging (MRI) for diagnosing meniscal tears, MR findings do not always agree with surgical findings. We performed a blinded, retrospective study to analyze the nature and frequency of errors in the MR diagnosis of meniscal tears. Medical records of 100 consecutive patients who underwent MR and arthroscopy of the knee at our institution were reviewed. Twelve patients underwent prior meniscal surgery. Twenty-three patients had 27 discrepancies between MR and surgical findings. These were independently reviewed by two additional musculoskeletal radiologists in a double blinded fashion. Original incorrect diagnoses were categorized as either unavoidable, interpretation error or equivocal for meniscal tear. MR accuracy was 88% for the medial and 85% for the lateral meniscus. Of 27 incorrect MR diagnoses, 12 (44%) were unavoidable, 10 (37%) equivocal and 5 (19%) interpretation errors. Of the 67 medial meniscal tears, 12 (18%) were missed. Eight (67%) of these 12 were categorized as equivocal, including three postoperative menisci. Of 30 lateral tears, 12 (40%) were missed, 7 (58%) of which were categorized as unavoidable. Of these 12, 11 (92%) showed fraying of the inner edge, which was shaved at arthroscopy (n = 8) or had stable tear treated conservatively (n = 3). There were three false-positive diagnoses, all occuring in the lateral meniscus, two of which were unavoidable and one interpretation error. Of all missed lateral meniscal tears, most are unavoidable and related to confusion between what represents fraying and what represents a tear. Unavoidable false-positive diagnoses are infrequent and may be related to incomplete arthroscopic evaluation. Subtle or equivocal findings still make MR diagnosis difficult, even for experienced radiologists.

  15. Structural knee joint pathology in patients aged 40 years or older with meniscal tears

    DEFF Research Database (Denmark)

    Pihl, Kenneth; Englund, Martin; Lohmander, L S

    2017-01-01

    Purpose: Recent studies have challenged the tenet that mechanical symptoms of the knee (i.e. the sensation of catching or locking) are caused by degenerative meniscal tears per se and relieved by surgery. We explored the potential associations between meniscal and other knee joint pathologies...... identified at meniscal surgery with the presence of patient-reported mechanical symptoms. Methods: This study included patients aged 40 years or older undergoing surgery for a meniscal tear from the Knee Arthroscopy Cohort Southern Denmark (KACS). Patients were consecutively recruited from February 2013...... score (KOOS), together with information on previous meniscal surgery. At arthroscopy, the operating surgeon recorded information about specific meniscal pathology (tear location, depth, type, length, meniscal tissue quality and circumferential and radial location) and other structural knee pathologies...

  16. Patient reported outcomes in patients undergoing arthroscopic partial meniscectomy for traumatic or degenerative meniscal tears

    DEFF Research Database (Denmark)

    Thorlund, Jonas Bloch; Englund, Martin; Christensen, Robin

    2017-01-01

    OBJECTIVES: To compare patient reported outcomes from before surgery to 52 weeks after surgery between individuals undergoing arthroscopic partial meniscectomy for traumatic meniscal tears and those for degenerative meniscal tears. DESIGN: Comparative prospective cohort study. SETTING: Four public......-55, and undergoing arthroscopic partial meniscectomy for a traumatic or degenerative meniscal tear (defined by a combination of age and symptom onset). INTERVENTIONS: Both participant groups underwent arthroscopic partial meniscectomy for a meniscal tear, with operating surgeons recording relevant information......% women) with a traumatic or degenerative meniscal tear (n=141, mean age 38.7 years (standard deviation 10.9); n=256, 46.6 years (6.4); respectively) were included in the main analysis. At 52 weeks after arthroscopic partial meniscectomy, 55 (14%) patients were lost to follow-up. Statistically...

  17. Impact of type of meniscal tear on radiographic and symptomatic knee osteoarthritis

    DEFF Research Database (Denmark)

    Englund, M; Roos, Ewa M.; Lohmander, L S

    2003-01-01

    To investigate long-term radiographic and patient-relevant outcome of isolated limited meniscectomy with regard to type of meniscal tear and extent of surgical resection.......To investigate long-term radiographic and patient-relevant outcome of isolated limited meniscectomy with regard to type of meniscal tear and extent of surgical resection....

  18. Signs of knee osteoarthritis common in 620 patients undergoing arthroscopic surgery for meniscal tear

    DEFF Research Database (Denmark)

    Pihl, Kenneth; Englund, Martin; Lohmander, L. Stefan

    2017-01-01

    Background and purpose - Recent evidence has questioned the effect of arthroscopic knee surgery for middle-aged and older patients with degenerative meniscal tears with or without concomitant radiographic knee osteoarthritis (OA). We investigated the prevalence of early or more established knee OA...... and patients' characteristics in a cohort of patients undergoing arthroscopic surgery for a meniscal tear. Patients and methods - 641 patients assigned for arthroscopy on suspicion of meniscus tear were consecutively recruited from February 2013 through January 2015. Of these, 620 patients (mean age 49 (18...... established knee OA was present in 43% of patients undergoing knee arthroscopy for meniscal tear....

  19. Similar failure rate in immediate post-operative weight bearing versus protected weight bearing following meniscal repair on peripheral, vertical meniscal tears.

    Science.gov (United States)

    Perkins, Bryan; Gronbeck, Kyle R; Yue, Ruixian Alexander; Tompkins, Marc A

    2017-08-16

    Post-operative weight bearing after meniscal repair is a point of debate among physicians. This study sought to evaluate whether patients adhering to an immediate WBAT rehabilitation programme have a higher failure rate compared to those adhering to a more traditional, protected, NWB status following meniscal repair. The null hypothesis was that there would be no difference in failure between the two groups. A retrospective review of meniscal repair patients greater than 5 years from surgery was performed for patients receiving meniscal repair treatment. Patients were categorized by post-surgical weight-bearing status, either NWB or WBAT, and then analysed for failure of repair. Failure was defined as re-operation on the torn meniscus. The study controlled for variables including age at surgery, sex, height, weight, and BMI, classification of tear type, acuity of the tear, repair location (medial or lateral), repair location within the meniscus, repair technique, and concomitant procedures. Re-operations were performed in 61 of 157 patients [38.9%]. There was no difference between weight-bearing groups for failure of meniscus repair (n.s.). The tears were acute vertical tears located in the posterior horn and body. For the 61 patients with re-operation, the average time to re-operation was 2.2 years with 10 [16%] > 5 years from surgery, 17 [28%] 2-5 years from surgery, and 34 [56%] bearing groups for rate of re-operation (n.s.). Weight bearing as tolerated after meniscal repair for peripheral, vertical tears does not result in a higher failure rate than traditional, non-weight bearing over a five-year follow-up period. The clinical relevance is that, based on these data, it may be appropriate to allow weight bearing as tolerated following meniscal repair of peripheral, vertical tears. Retrospective cohort study, Level III.

  20. Isolated medial meniscal tear in a Border Collie.

    Science.gov (United States)

    Ridge, P A

    2006-01-01

    A three-year-old, female Border Collie was successfully treated for an isolated, torn, medial meniscus by arthroscopic meniscal tear resection. The dog returned to agility competition without recurrence of lameness.

  1. The role of biomaterials in the treatment of meniscal tears

    Directory of Open Access Journals (Sweden)

    Crystal O. Kean

    2017-11-01

    Full Text Available Extensive investigations over the recent decades have established the anatomical, biomechanical and functional importance of the meniscus in the knee joint. As a functioning part of the joint, it serves to prevent the deterioration of articular cartilage and subsequent osteoarthritis. To this end, meniscus repair and regeneration is of particular interest from the biomaterial, bioengineering and orthopaedic research community. Even though meniscal research is previously of a considerable volume, the research community with evolving material science, biology and medical advances are all pushing toward emerging novel solutions and approaches to the successful treatment of meniscal difficulties. This review presents a tactical evaluation of the latest biomaterials, experiments to simulate meniscal tears and the state-of-the-art materials and strategies currently used to treat tears.

  2. MR imaging of displaced meniscal tears of the knee. Importance of a 'disproportional posterior horn sign'

    International Nuclear Information System (INIS)

    Chen, H.C.; Hsu, C.Y.; Shih, T.T.F.; Huang, K.M.; Li, Y.W.

    2001-01-01

    Purpose: Meniscal tears associated with displaced fragments are clinically significant. We propose the 'disproportional posterior horn sign' as a supportive criterion to identify a posterocentrally displaced meniscal fragment on MR imaging studies. If the meniscal posterior horn in the central portion appears larger than that in the peripheral section, it is considered positive for 'disproportional posterior horn sign'. Material and Methods: MR images obtained in 42 patients with 43 lesions, confirmed to have displaced meniscal tears, were included in this study. The MR images were retrospectively evaluated for the presence of the 'disproportional posterior horn sign', as well as the other known signs. Results: The 'disproportional posterior horn sign' was seen in 9 (20.9%) of 43 lesions, including 1 lateral discoid meniscal tear, 5 lateral meniscal tears and 3 medial meniscal tears. Five of them also had other signs of a displaced meniscal fragment. However, the remaining 4 cases only exhibited the 'disproportional posterior horn sign'. For the other MR signs, the 'absent bow tie sign' was detected in 40 (93%) of 43 lesions, the 'flipped meniscus sign' in 27 (62.8%) of 43 lesions, the 'double posterior cruciate ligament sign' in 17 (39.5%) of 43 lesions and the 'notch fragment sign' in 22 (51.2%) of 43 lesions. Conclusion: The 'disproportional posterior horn sign' is helpful in demonstrating a posterocentrally displaced meniscal fragment, especially when other characteristic signs are unremarkable or absent

  3. Longitudinal follow-up of patients with conservatively treated and arthroscopically repaired peripheral meniscal tears

    International Nuclear Information System (INIS)

    Deutsch, A.L.; Mink, J.H.; Rothman, B.J.

    1989-01-01

    Tears involving the peripheral third of the meniscus represent an important subgroup of meniscal injuries due to their unique ability to heal by synovial ingrowth and vascular proliferation. Serial MR images were obtained in 14 patients with arthroscopically proved peripheral meniscal tears to assess changes in MR appearance associated with meniscal healing. Six patients were treated conservatively, and eight underwent arthroscopic repair. All patients were considered clinically stable and presumably healed based on commonly accepted orthopedic criteria. Persistent grade 3 signal was seen in all patients up to 6 months after injury. In two patients more than 14 months after repair, grade 3 signal was present but decreased. In no patient did the signal entirely resolve. The authors concluded that signal from conservatively treated and repaired meniscal tears may persist long after the tear has become asymptomatic and presumable healed. This likely reflects known histologic differences between the native meniscus and reparative fibrocartilage. Persistence of grade 3 signal should not be interpreted as reflective of nonhealing in patients with persistent symptoms or as evidence of another tear in those with recurrent symptoms

  4. Surgical interventions for meniscal tears: a closer look at the evidence.

    Science.gov (United States)

    Mutsaerts, Eduard L A R; van Eck, Carola F; van de Graaf, Victor A; Doornberg, Job N; van den Bekerom, Michel P J

    2016-03-01

    The aim of the present study was to compare the outcomes of various surgical treatments for meniscal injuries including (1) total and partial meniscectomy; (2) meniscectomy and meniscal repair; (3) meniscectomy and meniscal transplantation; (4) open and arthroscopic meniscectomy and (5) various different repair techniques. The Bone, Joint and Muscle Trauma Group Register, Cochrane Database, MEDLINE, EMBASE and CINAHL were searched for all (quasi) randomized controlled clinical trials comparing various surgical techniques for meniscal injuries. Primary outcomes of interest included patient-reported outcomes scores, return to pre-injury activity level, level of sports participation and persistence of pain using the visual analogue score. Where possible, data were pooled and a meta-analysis was performed. A total of nine studies were included, involving a combined 904 subjects, 330 patients underwent a meniscal repair, 402 meniscectomy and 160 a collagen meniscal implant. The only surgical treatments that were compared in homogeneous fashion across more than one study were the arrow and inside-out technique, which showed no difference for re-tear or complication rate. Strong evidence-based recommendations regarding the other surgical treatments that were compared could not be made. This meta-analysis illustrates the lack of level I evidence to guide the surgical management of meniscal tears. Level I meta-analysis.

  5. Study protocol for a randomised controlled trial of meniscal surgery compared with exercise and patient education for treatment of meniscal tears in young adults

    DEFF Research Database (Denmark)

    Skou, Soren Thorgaard; Lind, Martin; Holmich, Per

    2017-01-01

    INTRODUCTION: Arthroscopic surgery is a very common orthopaedic procedure. While several trials have investigated the effect of knee arthroscopy for middle-aged and older patients with meniscal tears, there is a paucity of trials comparing meniscal surgery with non-surgical treatment for younger...... adults. The aim of this randomised controlled trial (RCT) is to investigate if early arthroscopic surgery is superior to exercise therapy and education, with the option of later surgery if needed, in improving pain, function and quality of life in younger adults with meniscal tears. METHODS AND ANALYSIS......: This is a protocol for a multicentre, parallel-group RCT conducted at six hospitals across all five healthcare regions in Denmark. 140 patients aged 18-40 years with a clinical history and symptoms consistent with a meniscal tear, verified on MRI, found eligible for meniscal surgery by an orthopaedic surgeon...

  6. MRI evaluation of the bucket handle tears of menisci of the knee

    International Nuclear Information System (INIS)

    Zheng Zhuozhao; Fan Jiadong; Xie Jingxia

    2003-01-01

    Objective: To determine the value of five MR imaging signs in diagnosing the bucket handle tears (BHT) of menisci of the knee. Methods: MR imaging of 139 knees with subsequent arthroscopy exams were retrospectively evaluated. Based on the results of arthroscopy, 19 knees had BHT of menisci. Two radiologists evaluated each MR exam independently, with discrepancies resolved by consensus. Each MR exam was analyzed for five signs: a double posterior cruciate ligament sign, a flipped meniscus sign, an absent bow tie sign, an internal displaced fragment sign, and an abnormal circumferential meniscus sign. Sensitivity, specificity, positive and negative predictive values, and accuracy for diagnosing BHT of menisci were calculated for the presence of each individual sign. Results: The sensitivities of these five signs ranged between 52.6% and 89.5%, and specificities ranged between 83.3% and 98.3%, respectively. Positive and negative predictive values ranged between 42.9% and 88.2%, and between 92.7% and 98.3%, respectively. The accuracy of these five signs ranged between 82.7% and 96.4%. Conclusion: BHT of menisci may have many signs on MR imaging. The diagnostic sensitivities of the internal displaced fragment sign and the abnormal circumferential meniscus sign are the highest. The double posterior cruciate ligament sign has the highest specificity and positive predictive value, while the internal displaced fragment sign has the highest negative predictive value and accuracy

  7. Association of MRI findings and expert diagnosis of symptomatic meniscal tear among middle-aged and older adults with knee pain.

    Science.gov (United States)

    Deshpande, Bhushan R; Losina, Elena; Smith, Savannah R; Martin, Scott D; Wright, R John; Katz, Jeffrey N

    2016-04-11

    Our aim was to examine the association between an expert clinician's impression of symptomatic meniscal tears and subsequent MRI in the context of middle-aged and older adults with knee pain. Patients older than 45 were eligible for this IRB-approved substudy if they had knee pain, had not undergone MRI and saw one of two orthopaedic surgeons experienced in the diagnosis of meniscal tear. The surgeon rated their confidence that the patient's symptoms were due to meniscal tear. The patient subsequently had a 1.5 or 3.0 T MRI within 6 months. We examined the association between presence of meniscal tear on MRI and the surgeon's confidence that the knee pain was due to meniscal tear using a χ(2) test for trend. Of 84 eligible patients, 63% were female, with a mean age of 64 years and a mean BMI of 27. The surgeon was confident that symptoms emanated from a tear among 39%. The prevalence of meniscal tear on MRI overall was 74%. Among subjects whose surgeon indicated high confidence that symptoms were due to meniscal tear, the prevalence was 80% (95% CI 63-90%). Similarly, the prevalence was 87% (95% CI 62-96%) among those whose surgeon had medium confidence and 64% (95% CI 48-77%) among those whose surgeon had low confidence (p = 0.12). Meniscal tears were frequently found on MRI even when an expert clinician was confident that a patient's knee symptoms were not due to a meniscal tear, indicating that providers should use MRI sparingly and cautiously to confirm or rule out the attribution of knee pain to meniscal tear.

  8. Usefulness of turbo spin-echo MR imaging in meniscal tears of the knee

    International Nuclear Information System (INIS)

    Jeong, Gun Young; Choi, Chang Lak; Chung, Jin Young; Han, Tae Il; Jang, Hong Im; Kim, Ji Min; Han, Hyun Young; Song, Mun Kab; Yang, Chang Kyu

    1998-01-01

    To evaluate the usefulness and diagnostic accuracy of turbo spin-echo(TSE) proton-density and T2-weighted images of meniscal tears of the knee. We retrospectively evaluated the sensitivity, specificity, and accuracy of TSE proton density and T2-weighted images of meniscal tears confirmed arthroscopically or surgically in 47 patients(98 menisci). The routine TSE parameters used in all patients were the dual echo sequence with sagittal proton density and T2-weighed images(4000/16, 90/5/2 [TR/effectiveTE/ETL/NEX]), and fat-suppressed coronal proton density and T2-weighted images. The chi-square test was used for statistical analysis. The sensitivity, specificity, and accuracy of TSE proton density images for the detection of meniscal tears were 93.9%, 93.8%, and 93.9%, respectively, in the medial meniscus, and 92.9%, 91.4%, and 91.8% in the lateral. On T2-weighted images the corresponding figures were 87.9%, 8%, and 89.8%, respectively, in the medial meniscus, and 64.3%, 91.4%, and 83.7% in the lateral. With regard to sensitivity and accuracy, TSE proton density images of meniscal tears were superior to TSE T2-weighted images.=20

  9. Exercise therapy versus arthroscopic partial meniscectomy for degenerative meniscal tear in middle aged patients

    DEFF Research Database (Denmark)

    Kise, Nina Jullum; Risberg, May Arna; Stensrud, Silje

    2016-01-01

    Objective To determine if exercise therapy is superior to arthroscopic partial meniscectomy for knee function in middle aged patients with degenerative meniscal tears. Design Randomised controlled superiority trial. Setting Orthopaedic departments at two public hospitals and two physiotherapy...... clinics in Norway. Participants 140 adults, mean age 49.5 years (range 35.7-59.9), with degenerative medial meniscal tear verified by magnetic resonance imaging. 96% had no definitive radiographic evidence of osteoarthritis. Interventions 12 week supervised exercise therapy alone or arthroscopic partial....... Our results should encourage clinicians and middle aged patients with degenerative meniscal tear and no definitive radiographic evidence of osteoarthritis to consider supervised exercise therapy as a treatment option. Trial registration www.clinicaltrials.gov (NCT01002794)....

  10. Exercise therapy versus arthroscopic partial meniscectomy for degenerative meniscal tear in middle aged patients

    DEFF Research Database (Denmark)

    Kise, Nina Jullum; Risberg, May Arna; Stensrud, Silje

    2016-01-01

    OBJECTIVE: To determine if exercise therapy is superior to arthroscopic partial meniscectomy for knee function in middle aged patients with degenerative meniscal tears. DESIGN: Randomised controlled superiority trial. SETTING: Orthopaedic departments at two public hospitals and two physiotherapy...... clinics in Norway. PARTICIPANTS: 140 adults, mean age 49.5 years (range 35.7-59.9), with degenerative medial meniscal tear verified by magnetic resonance imaging. 96% had no definitive radiographic evidence of osteoarthritis. INTERVENTIONS: 12 week supervised exercise therapy alone or arthroscopic partial....... Our results should encourage clinicians and middle aged patients with degenerative meniscal tear and no definitive radiographic evidence of osteoarthritis to consider supervised exercise therapy as a treatment option.Trial registration www.clinicaltrials.gov (NCT01002794)....

  11. Occupational kneeling and meniscal tears: a magnetic resonance imaging study in floor layers

    DEFF Research Database (Denmark)

    Rytter, Søren; Jensen, Lilli Kirkeskov; Bonde, Jens Peter

    2009-01-01

    OBJECTIVE: To evaluate the association between occupational kneeling and degenerative meniscal tears. METHODS: Magnetic resonance imaging (MRI) of both knees was conducted in 92 male floor layers and 49 male graphic designers (referents), with a mean age of 55.6 years (range 42-70 yrs). The prese......OBJECTIVE: To evaluate the association between occupational kneeling and degenerative meniscal tears. METHODS: Magnetic resonance imaging (MRI) of both knees was conducted in 92 male floor layers and 49 male graphic designers (referents), with a mean age of 55.6 years (range 42-70 yrs......). The presence of grade 3 MRI signal intensities indicating degenerative tears of the anterior, middle, and posterior one-third of the lateral and medial menisci was assessed on 1.5-Tesla MRI scans. The odds ratio (OR) of meniscal tears was determined among floor layers compared to graphic designers. Using...... logistic regression, models were adjusted for age, body mass index, and knee-straining sports. RESULTS: Degenerative tears were significantly more prevalent in the medial meniscus among floor layers than among graphic designers [OR 2.28, 95% confidence interval (CI) 1.10-4.98] and significantly more floor...

  12. Meniscal tears: comparison of half-Fourier technique and conventional MR imaging

    International Nuclear Information System (INIS)

    Shabana, Wael; Maeseneer, Michel de; Machiels, Freddy; Ridder, Filip de; Osteaux, Michel

    2003-01-01

    Purpose: To determine whether half-Fourier MR image acquisition technique can provide similar information to that of conventional MR acquisition technique for evaluation of meniscal tears. Materials and methods: We studied 101 menisci in 52 patients who were referred for evaluation of meniscal tears. Sagittal MR images of the knee were obtained for all patients by using proton density and T2-weighted SE sequences on a 1-T clinical system. The half-Fourier technique and conventional technique were used for all patients. All other imaging parameters were identical for both sequences (TR/TE=2400/20,70; 3 mm slice thickness; 200x256 matrix; field of view, 200; one signal acquired). Both sets of images were filmed with standard window and level settings. Images were randomised and interpreted independently by two radiologists for the presence of meniscal tears. Images were also subjectively assessed for image quality using a five-point grading scale. Results: On half-Fourier images, Reader 1 interpreted 23 menisci as torn, compared to 28 for Reader 2. On conventional images, Reader 1 interpreted 24 menisci as torn, compared to 26 for Reader 2. Agreement between interpretation of the conventional and that of the half-Fourier images was 99% for Reader 1, and 98% for Reader 2. Agreement between readers for the half-Fourier images was 95%, and for the conventional images 96%. No statistically significant difference was found in the subjective evaluation of image quality between the conventional and half-Fourier images. Conclusion: The half-Fourier acquisition technique compares favourably with the conventional technique for the evaluation of meniscal tears

  13. Kissing contusion between the posterolateral tibial plateau and lateral femoral condyle: associated ligament and meniscal tears

    International Nuclear Information System (INIS)

    Hong, Hyun Pyo; Lee, Jae Gue; Park, Ji Seon; Ryu, Kyung Nam

    2004-01-01

    Kissing contusion between the posterolateral tibial plateau and lateral femoral condyle is frequently found in association with a tear of the anterior cruciate liagment (ACL). The purpose of this study was to determine which ligamentous and meniscal tears are associated with kissing contusion. We retrospectively reviewed the findings depicted by 323 consecutive MR images of the knee and confirmed at arthroscopy. For the diagnosis of disruption, ligaments, medial menisci (MM) and lateral menisci (LM) were evaluated using accepted criteria. We compared the prevalence and location of meniscal and ligamentous tears between group I (44 knees with kissing contusion) and group II (279 knees without kissing contusion). For statistical analysis the chi-square test was used. ACLs were torn in all 44 knees (100%) with kissing contusion, and 78 (28%) of 279 without kissing contusion. There were ten medial collateral ligament (MCL) tears (23%) in group I, and 17 MCL tears (6%), five lateral collateral ligament (LCL) tears (2%) and ten posterior cruciate ligament (PCL) tears (4%) in group II. In group I, meniscal tears were found in 22 MM (50%) and in 19 LM (43%), while in group II, they occurred in 128 MM (46%) and 128 LM (46%), In group I, 17 (77%) of 22 MM tears and 13 (68%) of 19 LM tears were located in the posterior horn, while in group II, the corresponding figures were 97/128 (76%) and 60 of 128 (47%). The differing prevalence of ACL and MCL tears between the groups was statistically significant (p 0.05). Although kissing contusion was a highly specific sign of ACL tears, its presence was also significant among MCL tears. There was no significant difference in meniscal tears with or without kissing contusion

  14. The relationship between prevalent medial meniscal intrasubstance signal changes and incident medial meniscal tears in women over a 1-year period assessed with 3.0 T MRI

    Energy Technology Data Exchange (ETDEWEB)

    Crema, Michel D. [Boston University School of Medicine, Department of Radiology, Quantitative Imaging Center, Boston, MA (United States); Ribeirao Preto School of Medicine, University of Sao Paulo (USP), Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus, and Department of Internal Medicine, Radiology Division, Ribeirao Preto (Brazil); Institute of Diagnostic Imaging (IDI), Ribeirao Preto (Brazil); Hunter, David J. [The University of Sydney, Sydney School of Medicine, Sydney (Australia); Roemer, Frank W. [Boston University School of Medicine, Department of Radiology, Quantitative Imaging Center, Boston, MA (United States); Klinikum Augsburg, Department of Radiology, Augsburg (Germany); Li, Ling [New England Baptist Hospital, Division of Research, Boston, MA (United States); Marra, Monica D. [Boston University School of Medicine, Department of Radiology, Quantitative Imaging Center, Boston, MA (United States); Institute of Diagnostic Imaging (IDI), Ribeirao Preto (Brazil); Nogueira-Barbosa, Marcello H. [Ribeirao Preto School of Medicine, University of Sao Paulo (USP), Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus, and Department of Internal Medicine, Radiology Division, Ribeirao Preto (Brazil); Hellio Le Graverand, Marie-Pierre; Wyman, Bradley T. [Pfizer Global Research and Development, New London, CT (United States); Guermazi, Ali [Boston University School of Medicine, Department of Radiology, Quantitative Imaging Center, Boston, MA (United States)

    2011-08-15

    Intrasubstance meniscal signal changes not reaching the articular surface on fast spin echo (FSE) sequences are considered to represent mucoid degeneration on MRI. The aim of this study was to evaluate the association of prevalent intrasubstance signal changes with incident tears of the medial meniscus detected on 3.0 T MRI over a 1-year period. A total of 161 women aged {>=}40 years participated in a longitudinal 1-year observational study of knee osteoarthritis. MRI (3.0 T) was performed at baseline and 12-month follow-up. The anterior horn, body, and posterior horn of the medial meniscus were scored by two experienced musculoskeletal radiologists using the Boston-Leeds Osteoarthritis Knee Score (BLOKS) system. Four grades were used to describe the meniscal morphology: grade 0 (normal), grade 1 (intrasubstance signal changes not reaching the articular surface), grade 2 (single tears), and grade 3 (complex tears and maceration). Fisher's exact test and the Cochran-Armitage trend test were performed to evaluate whether baseline intrasubstance signal changes (grade 1) predict incident meniscal tears/maceration (grades 2 and/or 3) in the same subregion of the medial meniscus, when compared to subregions without pathology as the reference group (grade 0). Medial meniscal intrasubstance signal changes at baseline did not predict tears at follow-up when evaluating the anterior and posterior horns (left-sided p-values 0.06 and 0.59, respectively). No incident tears were detected in the body. We could not demonstrate an association between prevalent medial meniscal intrasubstance signal changes with incident tears over a 1-year period. (orig.)

  15. The relationship between prevalent medial meniscal intrasubstance signal changes and incident medial meniscal tears in women over a 1-year period assessed with 3.0 T MRI

    International Nuclear Information System (INIS)

    Crema, Michel D.; Hunter, David J.; Roemer, Frank W.; Li, Ling; Marra, Monica D.; Nogueira-Barbosa, Marcello H.; Hellio Le Graverand, Marie-Pierre; Wyman, Bradley T.; Guermazi, Ali

    2011-01-01

    Intrasubstance meniscal signal changes not reaching the articular surface on fast spin echo (FSE) sequences are considered to represent mucoid degeneration on MRI. The aim of this study was to evaluate the association of prevalent intrasubstance signal changes with incident tears of the medial meniscus detected on 3.0 T MRI over a 1-year period. A total of 161 women aged ≥40 years participated in a longitudinal 1-year observational study of knee osteoarthritis. MRI (3.0 T) was performed at baseline and 12-month follow-up. The anterior horn, body, and posterior horn of the medial meniscus were scored by two experienced musculoskeletal radiologists using the Boston-Leeds Osteoarthritis Knee Score (BLOKS) system. Four grades were used to describe the meniscal morphology: grade 0 (normal), grade 1 (intrasubstance signal changes not reaching the articular surface), grade 2 (single tears), and grade 3 (complex tears and maceration). Fisher's exact test and the Cochran-Armitage trend test were performed to evaluate whether baseline intrasubstance signal changes (grade 1) predict incident meniscal tears/maceration (grades 2 and/or 3) in the same subregion of the medial meniscus, when compared to subregions without pathology as the reference group (grade 0). Medial meniscal intrasubstance signal changes at baseline did not predict tears at follow-up when evaluating the anterior and posterior horns (left-sided p-values 0.06 and 0.59, respectively). No incident tears were detected in the body. We could not demonstrate an association between prevalent medial meniscal intrasubstance signal changes with incident tears over a 1-year period. (orig.)

  16. MR accuracy and arthroscopic incidence of meniscal radial tears

    Energy Technology Data Exchange (ETDEWEB)

    Magee, Thomas; Shapiro, Marc; Williams, David [Department of Radiology, Neuroimaging Institute, 27 East Hibiscus Blvd., Melbourne, FL 32901 (United States)

    2002-12-01

    A meniscal radial tear is a vertical tear that involves the inner meniscal margin. The tear is most frequent in the middle third of the lateral meniscus and may extend outward in any direction. We report (1) the arthroscopic incidence of radial tears, (2) MR signs that aid in the detection of radial tears and (3) our prospective accuracy in detection of radial tears. Design and patients. Three musculoskeletal radiologists prospectively read 200 consecutive MR examinations of the knee that went on to arthroscopy by one orthopedic surgeon. MR images were assessed for location and MR characteristics of radial tears. MR criteria used for diagnosis of a radial tear were those outlined by Tuckman et al.: truncation, abnormal morphology and/or lack of continuity or absence of the meniscus on one or more MR images. An additional criterion used was abnormal increased signal in that area on fat-saturated proton density or T2-weighted coronal and sagittal images. Prospective MR readings were correlated with the arthroscopic findings.Results. Of the 200 consecutive knee arthroscopies, 28 patients had radial tears reported arthroscopically (14% incidence). MR readings prospectively demonstrated 19 of the 28 radial tears (68% sensitivity) when the criteria for diagnosis of a radial tear were truncation or abnormal morphology of the meniscus. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted or proton density weighted sequences, the prospective sensitivity was 25 of 28 radial tears (89% sensitivity). There were no radial tears described in MR reports that were not demonstrated on arthroscopy (i.e., there were no false positive MR readings of radial tears in these 200 patients). Radial tears are commonly seen at arthroscopy. There was a 14% incidence in this series of 200 patients who underwent arthroscopy. Prospective detection of radial tears was 68% as compared with arthroscopy when the criteria as

  17. MR accuracy and arthroscopic incidence of meniscal radial tears

    International Nuclear Information System (INIS)

    Magee, Thomas; Shapiro, Marc; Williams, David

    2002-01-01

    A meniscal radial tear is a vertical tear that involves the inner meniscal margin. The tear is most frequent in the middle third of the lateral meniscus and may extend outward in any direction. We report (1) the arthroscopic incidence of radial tears, (2) MR signs that aid in the detection of radial tears and (3) our prospective accuracy in detection of radial tears. Design and patients. Three musculoskeletal radiologists prospectively read 200 consecutive MR examinations of the knee that went on to arthroscopy by one orthopedic surgeon. MR images were assessed for location and MR characteristics of radial tears. MR criteria used for diagnosis of a radial tear were those outlined by Tuckman et al.: truncation, abnormal morphology and/or lack of continuity or absence of the meniscus on one or more MR images. An additional criterion used was abnormal increased signal in that area on fat-saturated proton density or T2-weighted coronal and sagittal images. Prospective MR readings were correlated with the arthroscopic findings.Results. Of the 200 consecutive knee arthroscopies, 28 patients had radial tears reported arthroscopically (14% incidence). MR readings prospectively demonstrated 19 of the 28 radial tears (68% sensitivity) when the criteria for diagnosis of a radial tear were truncation or abnormal morphology of the meniscus. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted or proton density weighted sequences, the prospective sensitivity was 25 of 28 radial tears (89% sensitivity). There were no radial tears described in MR reports that were not demonstrated on arthroscopy (i.e., there were no false positive MR readings of radial tears in these 200 patients). Radial tears are commonly seen at arthroscopy. There was a 14% incidence in this series of 200 patients who underwent arthroscopy. Prospective detection of radial tears was 68% as compared with arthroscopy when the criteria as

  18. Middle-aged patients with an MRI-verified medial meniscal tear report symptoms commonly associated with knee osteoarthritis

    DEFF Research Database (Denmark)

    Hare, Kristoffer B.; Stefan Lohmander, L.; Kise, Nina Jullum

    2017-01-01

    Background and purpose — No consensus exists on when to perform arthroscopic partial meniscectomy in patients with a degenerative meniscal tear. Since MRI and clinical tests are not accurate in detecting a symptomatic meniscal lesion, the patient’s symptoms often play a large role when deciding...... when to perform surgery. We determined the prevalence and severity of self-reported knee symptoms in patients eligible for arthroscopic partial meniscectomy due to a degenerative meniscal tear. We investigated whether symptoms commonly considered to be related to meniscus injury were associated...... with early radiographic signs of knee osteoarthritis. Patients and methods — We included individual baseline items from the Knee injury and Osteoarthritis Outcome Score collected in 2 randomized controlled trials evaluating treatment for an MRI-verified degenerative medial meniscal tears in 199 patients aged...

  19. Posterior horn lateral meniscal tears simulating meniscofemoral ligament attachment in the setting of ACL tear: MRI findings

    International Nuclear Information System (INIS)

    Park, Lawrence S.; Jacobson, Jon A.; Jamadar, David A.; Caoili, Elaine; Kalume-Brigido, Monica; Wojtys, Edward

    2007-01-01

    We have noted apparent far lateral meniscal attachment of the meniscofemoral ligament (MFL) with an anterior cruciate ligament (ACL) tear. This study evaluates MFL attachment and association with posterior horn lateral meniscus (PHLM) tear. Nine months of knee arthroscopy reports were reviewed to classify the PHLM and ACL as torn or normal. After excluding those with prior knee surgery, MR images were reviewed by two radiologists to determine the number of images lateral to PCL, which showed the ligaments of Humphrey and Wrisberg visible as structures separate from the PHLM. Any patient with abnormal PHLM surface signal not continuous with the MFL was excluded. MRI findings were compared with arthroscopy using Student's t test and Fisher's exact test. Of the 54 participants, 5 had PHLM tears and 49 were normal. Twenty-one had ACL tears; all those with an PHLM tear had an ACL tear. The ligament of Humphrey inserted on average 0.9 consecutive images lateral to the PCL without an PHLM tear and 4.7 with an PHLM tear; the ligament of Wrisberg inserted on average 3.0 consecutive images without an PHLM tear and 4.5 with an PHLM tear (slice thickness/gap = 3 mm/0.5 mm). There was a significant association between PHLM tear and number of images (p = 0.0028), and between ACL tear and this type of PHLM tear (p = 0.0064). Apparent far lateral meniscal extension of a meniscofemoral ligament (greater than or equal to four images lateral to the PCL) should be considered as a possible PHLM tear, especially in the setting of an ACL tear. (orig.)

  20. Trajectory of self-reported pain and function and knee extensor muscle strength in young patients undergoing arthroscopic surgery for meniscal tears

    DEFF Research Database (Denmark)

    Thorlund, Jonas Bloch; Østengaard, Lasse; Cardy, Nathan

    2017-01-01

    . PATIENTS AND INTERVENTION: People aged 30 years or younger undergoing surgery for a meniscal tear. OUTCOMES: and comparator: (1) Self-reported pain and function in patients undergoing meniscal surgery compared to a non-operative control group (2). Knee extensor strength in the leg undergoing surgery...... the trajectory of self-reported pain and function in patients undergoing arthroscopic surgery compared with non-operative treatments for young patients with meniscal tears. Knee extensor strength seemed to be impaired up to 12 months after surgery in young patients undergoing surgery for meniscal tears...

  1. Comparison of CT and MRI in patients with tibial plateau fracture: can CT findings predict ligament tear or meniscal injury?

    International Nuclear Information System (INIS)

    Mui, Leonora W.; Engelsohn, Eliyahu; Umans, Hilary

    2007-01-01

    (1) To determine the accuracy of computed tomography (CT) in the evaluation of ligament tear and avulsion in patients with tibial plateau fracture. (2) To evaluate whether the presence or severity of fracture gap and articular depression can predict meniscal injury. A fellowship-trained musculoskeletal radiologist retrospectively reviewed knee CT and MRI examinations of 41 consecutive patients presenting to a level 1 trauma center with tibial plateau fractures. Fracture gap, articular depression, ligament tear and footprint avulsions were assessed on CT examinations. The MRI studies were examined for osseous and soft tissue injuries, including meniscal tear, meniscal displacement, ligament tear, and ligament avulsion. CT demonstrated torn ligaments with 80% sensitivity and 98% specificity. Only 2% of ligaments deemed intact on careful CT evaluation had partial or complete tears on MRI. Although the degree of fracture gap and articular depression was significantly greater in patients with meniscal injury compared with those without meniscal injury, ROC analysis demonstrated no clear threshold for gap or depression that yielded a combination of high sensitivity and specificity. In the acute setting, CT offers high sensitivity and specificity for depicting osseous avulsions, as well as high negative predictive value for excluding ligament injury. However, MRI remains necessary for the preoperative detection of meniscal injury. (orig.)

  2. Changes in rates of arthroscopy due to degenerative knee disease and traumatic meniscal tears in Finland and Sweden.

    Science.gov (United States)

    Mattila, Ville M; Sihvonen, Raine; Paloneva, Juha; Felländer-Tsai, Li

    2016-02-01

    Knee arthroscopy is commonly performed to treat degenerative knee disease symptoms and traumatic meniscal tears. We evaluated whether the recent high-quality randomized control trials not favoring arthroscopic surgery for degenerative knee disease affected the procedure incidence and trends in Finland and Sweden. We conducted a bi-national registry-based study including all adult (aged ≥18 years) inpatient and outpatient arthroscopic surgeries performed for degenerative knee disease (osteoarthritis (OA) and degenerative meniscal tears) and traumatic meniscal tears in Finland between 1997 and 2012, and in Sweden between 2001 and 2012. In Finland, the annual number of operations was 16,389 in 1997, reached 20,432 in 2007, and declined to 15,018 in 2012. In Sweden, the number of operations was 9,944 in 2001, reached 11,711 in 2008, and declined to 8,114 in 2012. The knee arthroscopy incidence for OA was 124 per 10(5) person-years in 2012 in Finland and it was 51 in Sweden. The incidence of knee arthroscopies for meniscal tears coded as traumatic steadily increased in Finland from 64 per 10(5) person-years in 1997 to 97 per 10(5) person-years in 2012, but not in Sweden. The incidence of arthroscopies for degenerative knee disease declined after 2008 in both countries. Remarkably, the incidence of arthroscopy for degenerative knee disease and traumatic meniscal tears is 2 to 4 times higher in Finland than in Sweden. Efficient implementation of new high-quality evidence in clinical practice could reduce the number of ineffective surgeries.

  3. Changes in rates of arthroscopy due to degenerative knee disease and traumatic meniscal tears in Finland and Sweden

    Science.gov (United States)

    Mattila, Ville M; Sihvonen, Raine; Paloneva, Juha; Felländer-Tsai, Li

    2016-01-01

    Background and purpose Knee arthroscopy is commonly performed to treat degenerative knee disease symptoms and traumatic meniscal tears. We evaluated whether the recent high-quality randomized control trials not favoring arthroscopic surgery for degenerative knee disease affected the procedure incidence and trends in Finland and Sweden. Patients and methods We conducted a bi-national registry-based study including all adult (aged ≥18 years) inpatient and outpatient arthroscopic surgeries performed for degenerative knee disease (osteoarthritis (OA) and degenerative meniscal tears) and traumatic meniscal tears in Finland between 1997 and 2012, and in Sweden between 2001 and 2012. Results In Finland, the annual number of operations was 16,389 in 1997, reached 20,432 in 2007, and declined to 15,018 in 2012. In Sweden, the number of operations was 9,944 in 2001, reached 11,711 in 2008, and declined to 8,114 in 2012. The knee arthroscopy incidence for OA was 124 per 105 person-years in 2012 in Finland and it was 51 in Sweden. The incidence of knee arthroscopies for meniscal tears coded as traumatic steadily increased in Finland from 64 per 105 person-years in 1997 to 97 per 105 person-years in 2012, but not in Sweden. Interpretation The incidence of arthroscopies for degenerative knee disease declined after 2008 in both countries. Remarkably, the incidence of arthroscopy for degenerative knee disease and traumatic meniscal tears is 2 to 4 times higher in Finland than in Sweden. Efficient implementation of new high-quality evidence in clinical practice could reduce the number of ineffective surgeries. PMID:26122621

  4. The Relationship between Chondromalacia Patella, Medial Meniscal Tear and Medial Periarticular Bursitis in Patients with Osteoarthritis.

    Science.gov (United States)

    Resorlu, Mustafa; Doner, Davut; Karatag, Ozan; Toprak, Canan Akgun

    2017-12-01

    This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa) in osteoarthritis, chondromalacia patella and medial meniscal tears. Radiological findings of 100 patients undergoing magnetic resonance imaging with a preliminary diagnosis of knee pain were retrospectively evaluated by two radiologists. The first radiologist assessed all patients in terms of osteoarthritis, chondromalacia patella and medial meniscal tear. The second radiologist was blinded to these results and assessed the presence of bursitis in all patients. Mild osteoarthritis (grade I and II) was determined in 55 patients and severe osteoarthritis (grade III and IV) in 45 cases. At retropatellar cartilage evaluation, 25 patients were assessed as normal, while 29 patients were diagnosed with mild chondromalacia patella (grade I and II) and 46 with severe chondromalacia patella (grade III and IV). Medial meniscus tear was determined in 51 patients. Severe osteoarthritis and chondromalacia patella were positively correlated with meniscal tear (p chondromalacia patella (p = 0.023 and p = 0.479, respectively). Evaluation of lateral compartment bursae revealed lateral collateral ligament bursitis in 2 patients and iliotibial bursitis in 5 patients. We observed a greater prevalence of bursitis in the medial compartment of the knee in patients with severe osteoarthritis and medial meniscus tear.

  5. Comparison of SPECT bone scintigraphy with MRI for diagnosis of meniscal tears

    International Nuclear Information System (INIS)

    Tahmasebi, Mohammad-naghi; Saghari, Mohsen; Moslehi, Masoud; Gholamrezanezhad, Ali

    2005-01-01

    Scintigraphy has been considered as competitive to MRI, but limited data are available on the accuracy of single photon emission tomography (SPECT) compared with MRI for the assessment of meniscal tears. Our objective was to assess the value of SPECT in comparison to MRI. Between January 2003 and March 2004, sixteen patients were studied with both modalities and the accuracy rates of SPECT scan results, and MRI findings in the diagnosis of meniscal tears were compared. Arthroscopy was the gold standard. The respective sensitivity rate, specificity rate, and positive and negative predictive accuracies of MRI were 89%, 94%, 93%, and 79% and for SPECT those were 78%, 94%, 94%, and 88%. There was good agreement on the presence or absence of tears between two modalities (κ statistic = 0.699). SPECT and MRI are both valuable imaging techniques. SPECT is a useful alternative when MRI is unavailable or unsuitable and it is beneficial when more possible accuracy is desired (such as when MRI results are either inconclusive or conflict with other clinical data)

  6. [SPECIFIC DIAGNOSTIC SIGNIFICANCE OF "RIPPLE SIGN" OF MEDIAL FEMORAL CONDYLE UNDER ARTHROSCOPE IN MEDIAL LONGITUDINAL MENISCAL TEARS].

    Science.gov (United States)

    Ren Shiyou; Sun, Limang; Chen, Guofei; Jiang, Changqing; Zhang, Xintao; Zhang Wentao

    2015-01-01

    To investigate the reliability of the "ripple sign" on the upper surface of the medial femoral condyle in the diagnosis of medial longitudinal meniscal tears under arthroscope. Between June 2013 and June 2014, 56 patients with knee injuries were included. There were 35 males and 21 females with an average age of 22.2 years (range, 12-38 years). The causes of injury were sports in 40 cases, falling in 10 cases, and traffic accident in 6 cases. The injury was located at the left knee in 22 cases and at the right knee in 34 cases. The disease duration was 10-40 days (mean, 20.2 days). Of 56 patients, 15 cases had simple medial meniscal injury; 41 cases had combined injuries, including anterior cruciate ligament injury in 38 cases, posterior cruciate ligament injury in 2 cases, and patellar dislocation in 1 case. The "ripple sign" was observed under arthroscope before operation. Repair of medial meniscal injury and reconstruction of cruciate ligament were performed. The positive "ripple sign" was seen under arthroscope in all patients, who were diagnosed to have longitudinal meniscal tears, including 23 cases of mild "ripple sign" , 28 cases of moderate "ripple sign", and 5 cases of severe "ripple sign". The "ripple sign" on the upper surface of the medial femoral condyle is a reliable diagnostic evidence of medial longitudinal meniscal tears.

  7. Risk factors, diagnosis and non-surgical treatment for meniscal tears

    DEFF Research Database (Denmark)

    Thorlund, Jonas Bloch; Juhl, Carsten Bogh; Ingelsrud, Lina Holm

    2018-01-01

    quantitatively or qualitatively, as appropriate. Strength of evidence was determined according to the Grading of Recommendations Assessment Development and Evaluation framework. Low-quality evidence suggested that overweight (degenerative tears, k=3), male sex (k=4), contact and pivoting sports (k=2...... investigated exercise versus surgery (k=2) or the effect of surgery in addition to exercise (k=5) for degenerative meniscal tears. There was moderate level of evidence for exercise improving self-reported pain (Effect Size (ES)-0.51, 95% CI -1.16 to 0.13) and function (ES -0.06, 95% CI -0.23 to 0...

  8. The Relationship between Chondromalacia Patella, Medial Meniscal Tear and Medial Periarticular Bursitis in Patients with Osteoarthritis

    Science.gov (United States)

    Doner, Davut; Karatag, Ozan; Toprak, Canan Akgun

    2017-01-01

    Abstract Background This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa) in osteoarthritis, chondromalacia patella and medial meniscal tears. Patients and methods Radiological findings of 100 patients undergoing magnetic resonance imaging with a preliminary diagnosis of knee pain were retrospectively evaluated by two radiologists. The first radiologist assessed all patients in terms of osteoarthritis, chondromalacia patella and medial meniscal tear. The second radiologist was blinded to these results and assessed the presence of bursitis in all patients. Results Mild osteoarthritis (grade I and II) was determined in 55 patients and severe osteoarthritis (grade III and IV) in 45 cases. At retropatellar cartilage evaluation, 25 patients were assessed as normal, while 29 patients were diagnosed with mild chondromalacia patella (grade I and II) and 46 with severe chondromalacia patella (grade III and IV). Medial meniscus tear was determined in 51 patients. Severe osteoarthritis and chondromalacia patella were positively correlated with meniscal tear (p chondromalacia patella (p = 0.023 and p = 0.479, respectively). Evaluation of lateral compartment bursae revealed lateral collateral ligament bursitis in 2 patients and iliotibial bursitis in 5 patients. Conclusions We observed a greater prevalence of bursitis in the medial compartment of the knee in patients with severe osteoarthritis and medial meniscus tear. PMID:29333118

  9. Coronal oblique imaging of the knee: Can it increase radiologists' confidence in diagnosing posterior root meniscal tears?

    International Nuclear Information System (INIS)

    Casagranda, B.U.; Leeman, J.; Costello, J.M.; Rafiee, B.; Harner, C.D.

    2013-01-01

    Aim: To investigate the utility of the coronal oblique sequence in the interrogation of posterior root meniscal lesions. Materials and methods: Following international review board approval, 62 consecutive knee arthroscopy cases were referred to the musculoskeletal (MSK) radiologists from the same orthopaedic surgeon for imaging/surgical correlation of the posterior meniscal roots. Of 62 cases, 45 lateral and 46 medial menisci met the inclusion criteria. Imaging evaluation was performed with standard magnetic resonance imaging (MRI) sequences, including a coronal oblique proton density sequence. Two blinded fellowship-trained MSK radiologists independently evaluated the menisci on standard sequences indicating whether a tear was identified and then specifying a confidence score using a scale of 1–3 on each study interpreted. Immediately thereafter, the coronal oblique sequence was evaluated using the same method. Statistics were performed on meniscal lesions involving the posterior horn/root junction or isolated root tears comparing confidence scores. Results: Reader A identified nine posterior horn/root junction tears and 14 isolated root tears. Following the addition of the coronal oblique sequence, confidence scores increased in three of 14 (21.4%) isolated root tears. All three final reads were concordant with arthroscopy. Reader B identified 10 posterior horn/root junction tears and 19 isolated root tears. The confidence score increased in six cases: five of 19 (26.3%) isolated root tears and one of 10 (10%) posterior horn/root junction tears. All six final reads were concordant with arthroscopy. Kappa coefficients indicated near perfect agreement. Conclusion: The coronal oblique sequence increased reader confidence in nearly 24% of the posterior root cases identified in this series

  10. Patient-reported outcome measures for patients with meniscal tears: a systematic review of measurement properties and evaluation with the COSMIN checklist

    Science.gov (United States)

    Middleton, Robert; Beard, David J; Price, Andrew J; Hopewell, Sally

    2017-01-01

    Objective Meniscal tears occur frequently in the population and the most common surgical treatment, arthroscopic partial meniscectomy, is performed in approximately two million cases worldwide each year. The purpose of this systematic review is to summarise and critically appraise the evidence for the use of patient-reported outcome measures (PROMs) in patients with meniscal tears. Design A systematic review was undertaken. Data on reported measurement properties were extracted and the quality of the studies appraised according to Consensus-based Standards for the Selection of Health Measurement Instruments. Data sources A search of MEDLINE, Embase, AMED and PsycINFO, unlimited by language or publication date (last search 20 February 2017). Eligibility criteria for selecting studies Development and validation studies reporting the measurement properties of PROMs in patients with meniscal tears were included. Results 11 studies and 10 PROMs were included. The overall quality of studies was poor. For measurement of symptoms and functional status, there is only very limited evidence supporting the selection of either the Lysholm Knee Scale, International Knee Documentation Committee Subjective Knee Form or the Dutch version of the Knee injury and Osteoarthritis Outcome Score. For measuring health-related quality of life, only limited evidence supports the selection of the Western Ontario Meniscal Evaluation Tool (WOMET). Of all the PROMs evaluated, WOMET has the strongest evidence for content validity. Conclusion For patients with meniscal tears, there is poor quality and incomplete evidence regarding the validity of the currently available PROMs. Further research is required to ensure these PROMs truly reflect the symptoms, function and quality of life of patients with meniscal tears. PROSPERO registration number CRD42017056847. PMID:29030413

  11. Risk factors, diagnosis and non-surgical treatment for meniscal tears: evidence and recommendations: a statement paper commissioned by the Danish Society of Sports Physical Therapy (DSSF).

    Science.gov (United States)

    Thorlund, Jonas Bloch; Juhl, Carsten Bogh; Ingelsrud, Lina Holm; Skou, Søren Thorgaard

    2018-05-01

    This statement aimed at summarising and appraising the available evidence for risk factors, diagnostic tools and non-surgical treatments for patients with meniscal tears. We systematically searched electronic databases using a pragmatic search strategy approach. Included studies were synthesised quantitatively or qualitatively, as appropriate. Strength of evidence was determined according to the Grading of Recommendations Assessment Development and Evaluation framework. Low-quality evidence suggested that overweight (degenerative tears, k=3), male sex (k=4), contact and pivoting sports (k=2), and frequent occupational kneeling/squatting (k=3) were risk factors for meniscal tears. There was low to moderate quality evidence for low to high positive and negative predictive values, depending on the underlying prevalence of meniscal tears for four common diagnostic tests (k=15, n=2474). Seven trials investigated exercise versus surgery (k=2) or the effect of surgery in addition to exercise (k=5) for degenerative meniscal tears. There was moderate level of evidence for exercise improving self-reported pain (Effect Size (ES)-0.51, 95% CI -1.16 to 0.13) and function (ES -0.06, 95% CI -0.23 to 0.11) to the same extent as surgery, and improving muscle strength to a greater extent than surgery (ES -0.45, 95% CI -0.62 to -0.29). High-quality evidence showed no clinically relevant effect of surgery in addition to exercise on pain (ES 0.18, 95% 0.05 to 0.32) and function (ES, 0.13 95% CI -0.03 to 0.28) for patients with degenerative meniscal tears. No randomised trials comparing non-surgical treatments with surgery in patients younger than 40 years of age or patients with traumatic meniscal tears were identified. Diagnosis of meniscal tears is challenging as all clinical diagnostic tests have high risk of misclassification. Exercise therapy should be recommended as the treatment of choice for middle-aged and older patients with degenerative meniscal lesions. Evidence on

  12. Knee function and knee muscle strength in middle-aged patients with degenerative meniscal tears eligible for arthroscopic partial meniscectomy

    DEFF Research Database (Denmark)

    Stensrud, Silje; Risberg, May Arna; Roos, Ewa M.

    2014-01-01

    BACKGROUND: Functional limitations exist postmeniscectomy, but preoperative data are scarce. PURPOSE: To examine knee function, knee muscle strength and performance in middle-aged patients with degenerative meniscal tears, eligible for arthroscopic partial meniscectomy. STUDY DESIGN: Cross......-sectional study. METHODS: Eighty-two participants with MRI verified degenerative meniscal tear (35% women, mean age 49 years) answered the Knee injury and Osteoarthritis Outcome Score (KOOS) and were tested for isokinetic knee muscle strength and lower extremity performance (one-leg hop for distance, 6 m timed...

  13. Readability of Online Sources Regarding Meniscal Tears.

    Science.gov (United States)

    Hodax, Jonathan D; Baird, Grayson L; McBride, Trevor; Owens, Brett D

    2017-09-01

    Meniscal injuries are extremely common, with an incidence of 8.3 per 1,000 person/years in young, active individuals. Patients often turn to the internet to glean information about their injuries, and even to guide decision making about treatment. Much research has been done demonstrating that a reading level of eighth grade or lower is appropriate for accurately communicating written information to patients, yet medical practitioners often fail to meet this requirement. To better examine the information patients receive about meniscal injuries, we set out to evaluate the reading level and content of three commonly used search terms on the three search engines with the largest market share. The authors examined the keywords "meniscus tear," "meniscus tear treatment," and "knee pain meniscus" on the three highest market share search engines. The top 10 results from each search were included, and redundancies identified. Unique Web sites were evaluated for source, word count, reading level, and content including advertisements, diagrams, photographs, nonoperative and operative options, and accurate medical information. A total of 23 unique Web sites were identified in our search, including 13 public education sources, 6 academic institutions, and 4 private physicians/groups. Average grade levels of articles ranged from 9.4 to 14.2 (mean, 11.14; standard deviation [SD] 1.46), and Flesch-Kincaid reading ease scores ranged from 23.9 to 68.7 (mean, 55.31; SD, 10.11). Pages from public sources required the highest level of readability (11.6, 95% confidence interval [CI]: 9.8-13.2), which was significantly higher than private (11.0, 95% CI: 9.3, 12.7]) and academic (10.9, 95% CI: 8.9-12.9), p  = 0.007 and p  = 0.002, respectively. Further efforts to make appropriate health information available to patients are needed. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  14. Radiographic joint space narrowing in osteoarthritis of the knee: relationship to meniscal tears and duration of pain

    International Nuclear Information System (INIS)

    Chan, Wing P.; Huang, Guo-Shu; Hsu, Shu-Mei; Chang, Yue-Cune; Ho, Wei-Pin

    2008-01-01

    The objective of this study was to assess, with knee radiography, joint space narrowing (JSN) and its relationship to meniscal tears, anterior cruciate ligament (ACL) ruptures, articular cartilage erosion, and duration of pain in patients with knee osteoarthritis. A total of 140 patients who had knee osteoarthritis and underwent primary total knee replacement (TKR) surgery, with unicompartmental medial tibiofemoral JSN (grade 1 or greater) and normal lateral compartments, were recruited. Polytomous logistic regression was used to assess the relationship between JSN and risk factors. All patients with JSN were categorized as grade 1 (n=14, 10.0%), grade 2 (n=64, 45.7%), or grade 3 (n=62, 44.3%). Women presented with indications for a TKR at a younger age than men (mean age, 69 vs 73 years, P<0.05). There were 123 (87.9%) meniscal tears and 58 (41.4%) partial (insufficient or attenuated ACL fibers) and 10 (7.1%) complete ACL ruptures; 115 of 134 (85.8%) patients had moderate to severe cartilage erosion. A higher grade of JSN was correlated with a higher frequency of meniscal tears [odds ratio (OR) 6.00, 95% CI 1.29-27.96 for grade 2 vs grade 1 JSN] and duration of knee pain (OR 1.25, 95% CI 1.01-1.53 for grade 3 vs grade 1 JSN). A higher grade of JSN was not correlated with a higher frequency of ACL rupture or articular cartilage erosion. A higher grade of JSN is associated with a higher frequency of meniscal tears and long duration of knee pain in patients with knee osteoarthritis. (orig.)

  15. Radiographic joint space narrowing in osteoarthritis of the knee: relationship to meniscal tears and duration of pain

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Wing P. [Taipei Medical University, Department of Radiology, School of Medicine, Taipei (China); Taipei Medical University-Wan Fang Hospital, Department of Radiology, Taipei (China); Huang, Guo-Shu [Tri-Service General Hospital, National Defense Medical Center, Department of Radiology, Taipei (China); Hsu, Shu-Mei [Taipei Medical University, Department of Radiology, School of Medicine, Taipei (China); National Taiwan University, Department of Public Health, Taipei (China); Chang, Yue-Cune [Tamkang University, Department of Mathematics, Taipei County (China); Ho, Wei-Pin [Taipei Medical University-Wan Fang Hospital, Department of Orthopedic Surgery, Taipei (China)

    2008-10-15

    The objective of this study was to assess, with knee radiography, joint space narrowing (JSN) and its relationship to meniscal tears, anterior cruciate ligament (ACL) ruptures, articular cartilage erosion, and duration of pain in patients with knee osteoarthritis. A total of 140 patients who had knee osteoarthritis and underwent primary total knee replacement (TKR) surgery, with unicompartmental medial tibiofemoral JSN (grade 1 or greater) and normal lateral compartments, were recruited. Polytomous logistic regression was used to assess the relationship between JSN and risk factors. All patients with JSN were categorized as grade 1 (n=14, 10.0%), grade 2 (n=64, 45.7%), or grade 3 (n=62, 44.3%). Women presented with indications for a TKR at a younger age than men (mean age, 69 vs 73 years, P<0.05). There were 123 (87.9%) meniscal tears and 58 (41.4%) partial (insufficient or attenuated ACL fibers) and 10 (7.1%) complete ACL ruptures; 115 of 134 (85.8%) patients had moderate to severe cartilage erosion. A higher grade of JSN was correlated with a higher frequency of meniscal tears [odds ratio (OR) 6.00, 95% CI 1.29-27.96 for grade 2 vs grade 1 JSN] and duration of knee pain (OR 1.25, 95% CI 1.01-1.53 for grade 3 vs grade 1 JSN). A higher grade of JSN was not correlated with a higher frequency of ACL rupture or articular cartilage erosion. A higher grade of JSN is associated with a higher frequency of meniscal tears and long duration of knee pain in patients with knee osteoarthritis. (orig.)

  16. Utility of three-dimensional method for diagnosing meniscal lesions

    International Nuclear Information System (INIS)

    Ohshima, Suguru; Nomura, Kazutoshi; Hirano, Mako; Hashimoto, Noburo; Fukumoto, Tetsuya; Katahira, Kazuhiro

    1998-01-01

    MRI of the knee is a useful method for diagnosing meniscal tears. Although the spin echo method is usually used for diagnosing meniscal tears, we examined the utility of thin slice scan with the three-dimensional method. We reviewed 70 menisci in which arthroscopic findings were confirmed. In this series, sensitivity was 90.9% for medial meniscal injuries and 68.8% for lateral meniscal injuries. There were 3 meniscal tears in which we could not detect tears on preoperative MRI. We could find tears in two of these cases when re-evaluated using the same MRI. In conclusion, we can get the same diagnostic rate with the three-dimensional method compared with the spin echo method. Scan time of the three-dimensional method is 3 minutes, on the other hand that of spin echo method in 17 minutes. This slice scan with three-dimensional method is useful for screening meniscal injuries before arthroscopy. (author)

  17. The relationship between chondromalacia patella, medial meniscal tear and medial periarticular bursitis in patients with osteoarthritis

    Directory of Open Access Journals (Sweden)

    Resorlu Mustafa

    2017-11-01

    Full Text Available This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa in osteoarthritis, chondromalacia patella and medial meniscal tears.

  18. A biomechanical evaluation of all-inside 2-stitch meniscal repair devices with matched inside-out suture repair.

    Science.gov (United States)

    Ramappa, Arun J; Chen, Alvin; Hertz, Benjamin; Wexler, Michael; Grimaldi Bournissaint, Leandro; DeAngelis, Joseph P; Nazarian, Ara

    2014-01-01

    Many all-inside suture-based devices are currently available, including the Meniscal Cinch, FasT-Fix, Ultra FasT-Fix, RapidLoc, MaxFire, and CrossFix System. These different devices have been compared in various configurations, but to our knowledge, the Sequent meniscal repair device, which applies running sutures, has not been compared with the Ultra FasT-Fix, nor has it been compared with its suture, No. 0 Hi-Fi, using an inside-out repair technique. To assess the quality of the meniscal repair, all new devices should be compared with the gold standard: the inside-out repair. To that end, this study aims to compare the biomechanical characteristics of running sutures delivered by the Sequent meniscal repair device with 2 vertical mattress sutures applied using the Ultra FasT-Fix device and with 2 vertical mattress sutures using an inside-out repair technique with No. 0 Hi-Fi suture. Controlled laboratory study. Paired (medial and lateral), fresh-frozen porcine menisci were randomly assigned to 1 of 3 groups: Sequent (n = 17), Ultra FasT-Fix (n = 19), and No. 0 Hi-Fi inside-out repair (n = 20). Bucket-handle tears were created in all menisci and were subjected to repair according to their grouping. Once repaired, the specimens were subjected to cyclic loading (100, 300, and 500 cycles), followed by loading to failure. The Sequent and Ultra FasT-Fix device repairs and the suture repair exhibited low initial displacements. The Sequent meniscal repair device demonstrated the lowest displacement in response to cyclic loading. No. 0 Hi-Fi suture yielded the highest load to failure. With the development of the next generation of all-inside meniscal repair devices, surgeons may use these findings to select the method best suited for their patients. The Sequent meniscal repair device displays the least amount of displacement during cyclic loading but has a similar failure load to other devices.

  19. Effect of radial meniscal tear on in situ forces of meniscus and tibiofemoral relationship.

    Science.gov (United States)

    Tachibana, Yuta; Mae, Tatsuo; Fujie, Hiromichi; Shino, Konsei; Ohori, Tomoki; Yoshikawa, Hideki; Nakata, Ken

    2017-02-01

    To clarify the effect of the radial tear of the lateral meniscus on the in situ meniscus force and the tibiofemoral relationship under axial loads and valgus torques. Ten intact porcine knees were settled to a 6-degree of freedom robotic system, while the force and 3-dimensional path of the knees were recorded via Universal Force Sensor (UFS) during 3 cycles of 250-N axial load and 5-Nm valgus torque at 15°, 30°, 45°, and 60° of knee flexion. The same examination was performed on the following 3 meniscal states sequentially; 33, 66, and 100% width of radial tears at the middle segment of the lateral meniscus, while recording the force and path of the knees via UFS. Finally, all paths were reproduced after total lateral meniscectomy and the in situ force of the lateral meniscus were calculated with the principle of superposition. The radial tear of 100% width significantly decreased the in situ force of the lateral meniscus and caused tibial medial shift and valgus rotation at 30°-60° of knee flexion in both testing protocols. Under a 250-N axial load at 60° of knee flexion, the in situ force decreased to 36 ± 29 N with 100% width of radial tear, which was 122 ± 38 N in the intact state. Additionally, the tibia shifted medially by 2.1 ± 0.9 mm and valgusrotated by 2.5 ± 1.9° with the complete radial tear. However, the radial tear of 33 or 66% width had little effect on either the in situ force or the tibial position. A radial tear of 100% width involving the rim significantly decreased the in situ force of the lateral meniscus and caused medial shift and valgus rotation of the tibia, whereas a radial tear of up to 66% width produced only little change. The clinical relevance is that loss of meniscal functions due to complete radial tear can lead to abnormal stress concentration in a focal area of cartilage and can increase the risk of osteoarthritis in the future.

  20. The potential of optical coherence tomography for diagnosing meniscal pathology

    Science.gov (United States)

    Hang-Yin Ling, Carrie; Pozzi, Antonio; Thieman, Kelley M.; Tonks, Catherine A.; Guo, Shuguang; Xie, Huikai; Horodyski, MaryBeth

    2010-04-01

    Meniscal tears are often associated with anterior cruciate ligament (ACL) injury and may lead to pain and discomfort in humans. Maximal preservation of meniscal tissue is highly desirable to mitigate the progression of osteoarthritis. Guidelines of which meniscal tears are amenable to repair and what part of damaged tissues should be removed are elusive and lacking consensus. Images of microstructural changes in meniscus would potentially guide the surgeons to manage the meniscal tears better, but the resolution of current diagnostic techniques is limited for this application. In this study, we demonstrated the feasibility of using optical coherence tomography (OCT) for the diagnosis of meniscal pathology. Torn medial menisci were collected from dogs with ACL insufficiency. The torn meniscus was divided into three tissue samples and scanned by OCT and scanning electron microscopy (SEM). OCT and SEM images of torn menisci were compared. Each sample was evaluated for gross and microstructural abnormalities and reduction or loss of birefringence from the OCT images. The abnormalities detected with OCT were described for each type of tear. OCT holds promise in non-destructive and fast assessment of microstructural changes and tissue birefringence of meniscal tears. Future development of intraoperative OCT may help surgeons in the decision making of meniscal treatment.

  1. The potential of optical coherence tomography for diagnosing meniscal pathology

    International Nuclear Information System (INIS)

    Ling, Carrie Hang-Yin; Horodyski, MaryBeth; Pozzi, Antonio; Thieman, Kelley M; Tonks, Catherine A; Guo, Shuguang; Xie, Huikai

    2010-01-01

    Meniscal tears are often associated with anterior cruciate ligament (ACL) injury and may lead to pain and discomfort in humans. Maximal preservation of meniscal tissue is highly desirable to mitigate the progression of osteoarthritis. Guidelines of which meniscal tears are amenable to repair and what part of damaged tissues should be removed are elusive and lacking consensus. Images of microstructural changes in meniscus would potentially guide the surgeons to manage the meniscal tears better, but the resolution of current diagnostic techniques is limited for this application. In this study, we demonstrated the feasibility of using optical coherence tomography (OCT) for the diagnosis of meniscal pathology. Torn medial menisci were collected from dogs with ACL insufficiency. The torn meniscus was divided into three tissue samples and scanned by OCT and scanning electron microscopy (SEM). OCT and SEM images of torn menisci were compared. Each sample was evaluated for gross and microstructural abnormalities and reduction or loss of birefringence from the OCT images. The abnormalities detected with OCT were described for each type of tear. OCT holds promise in non-destructive and fast assessment of microstructural changes and tissue birefringence of meniscal tears. Future development of intraoperative OCT may help surgeons in the decision making of meniscal treatment

  2. PCL tibial avulsion with an associated medial meniscal tear in a child: a case report on diagnosis and management.

    LENUS (Irish Health Repository)

    2012-02-01

    Posterior cruciate ligament (PCL) injuries from tibial avulsions are rare in the paediatric setting. One would need a high index of suspicion as clinical examination may be difficult, especially in the early period. Magnetic resonance imaging is an excellent diagnostic modality for this condition and other associated injuries within the knee. We report a rare case in which the patient had a PCL avulsion off the tibial insertion site with an associated posterior horn medial meniscal tear off the posterior capsule. He was treated through open reduction and internal fixation of the avulsed fragment with suture repair of the meniscal tear. We emphasize the importance of diagnosing and managing associated intra-articular injuries when dealing with the rare condition of PCL tibial avulsion in the paediatric setting.

  3. MR imaging characteristics and clinical symptoms related to displaced meniscal flap tears

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Valentin; Heilmeier, Ursula R.; Joseph, Gabby B.; Steinbach, Lynne; Link, Thomas M. [University of California, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Ma, Benjamin [University of California, Department of Orthopedic Surgery and Sports Medicine, San Francisco (United States)

    2014-11-16

    The purpose of our study was (1) to analyze the flap tear location, direction of displacement and size on magnetic resonance (MR) imaging, (2) to describe associated knee abnormalities including presence of effusion, synovitis, bone marrow edema pattern or ligamentous tear, and (3) to assess clinical findings found with flap tears, including the pain score, and determine differences between operative and nonoperative groups. A retrospective radiology database search over the last 3 years identified 238 patients with flap tears, of which ultimately 58 with isolated flap tears were included after exclusion of patients with other significant knee internal derangement, severe degenerative change or prior surgery. MR studies of the knee were analyzed by two radiologists. Imaging characteristics were correlated with associated knee abnormalities and clinical findings. Statistical analysis employed linear and logistic regression models. Inter- and intrareader reliability was calculated. The medial meniscus was the most common site of flap tears (52/60, 87 %), with inferior displacement (47/60, 78 %). The degree of tibial cartilage loss had a positive correlation with the visual analog pain scale (p = 0.03). Patients who underwent arthroscopy were younger than those who did not (p = 0.01) and more likely to have a positive clinical McMurray test (p = 0.01). Medially and inferiorly displaced flap tears are the most common tear pattern. Those undergoing arthroscopy are more likely to have positive meniscal signs on clinical examination. A greater degree of cartilage loss involving the tibia on MR imaging was associated with increasing visual analog pain scores. (orig.)

  4. MR imaging characteristics and clinical symptoms related to displaced meniscal flap tears

    International Nuclear Information System (INIS)

    Lance, Valentin; Heilmeier, Ursula R.; Joseph, Gabby B.; Steinbach, Lynne; Link, Thomas M.; Ma, Benjamin

    2015-01-01

    The purpose of our study was (1) to analyze the flap tear location, direction of displacement and size on magnetic resonance (MR) imaging, (2) to describe associated knee abnormalities including presence of effusion, synovitis, bone marrow edema pattern or ligamentous tear, and (3) to assess clinical findings found with flap tears, including the pain score, and determine differences between operative and nonoperative groups. A retrospective radiology database search over the last 3 years identified 238 patients with flap tears, of which ultimately 58 with isolated flap tears were included after exclusion of patients with other significant knee internal derangement, severe degenerative change or prior surgery. MR studies of the knee were analyzed by two radiologists. Imaging characteristics were correlated with associated knee abnormalities and clinical findings. Statistical analysis employed linear and logistic regression models. Inter- and intrareader reliability was calculated. The medial meniscus was the most common site of flap tears (52/60, 87 %), with inferior displacement (47/60, 78 %). The degree of tibial cartilage loss had a positive correlation with the visual analog pain scale (p = 0.03). Patients who underwent arthroscopy were younger than those who did not (p = 0.01) and more likely to have a positive clinical McMurray test (p = 0.01). Medially and inferiorly displaced flap tears are the most common tear pattern. Those undergoing arthroscopy are more likely to have positive meniscal signs on clinical examination. A greater degree of cartilage loss involving the tibia on MR imaging was associated with increasing visual analog pain scores. (orig.)

  5. MR Imaging of a Posterior Root Tear of the Medial Meniscus: Diagnostic Accuracy of Various Tear Configurations and Associated Knee Abnormalities

    International Nuclear Information System (INIS)

    Lee, Hyang Mi; Shim, Jae Chan; Kim, Jin Goo; Lee, Jae Myeong; Nam, Mee Young; Lee, Ghi Jai; Kim, Ho Kyun; Suh, Jung Ho

    2010-01-01

    To evaluate the diagnostic accuracy of the various tear configurations in a medial meniscal posterior horn root tear and assess whether any correlation exists with other associated knee abnormalities in MR imaging. A retrospective review of 146 preoperative knee MR images were performed by one experienced musculoskeletal radiologist. The tear configuration and other abnormalities were evaluated. Sensitivity, specificity, and diagnostic accuracy of each configuration in the medial meniscal posterior horn root tear were calculated. A total of 48 medial meniscal posterior horn root tears including 38 full-thickness radial, 7 partial-thickness radial, and 3 complex tears were confirmed during arthroscopy. Overall, the sensitivity, specificity, and accuracy for the detection of medial meniscal posterior horn root tear were 92% (44/48), 99% (97/98), and 97% (141/146), respectively. For each tear configuration, sensitivity, specificity, and accuracy were 82% (31/38), 97% (105/108), and 93% (136/146) for full-thickness radial tears, respectively, and 43% (3/7), 94% (131/139), and 91% (134/146) for partial-thickness radial tears, respectively. The incidence of degenerative joint disease was 85% (41/48) for the tear group, revealing a strong association. In patients with a root tear and with degenerative joint disease, the incidence of high grade cartilage defects involving the medial femoral condyle was at 80% (33/41), compared to 56% (23/41) for the presence of medial meniscal extrusion. In contrast, a similar comparison of incidence for patients with no root tears but with degenerative joint disease was at 68% (17/25) and 26% (8/31), respectively. MR imaging is very sensitive for the detection of medial meniscal root tears, but has reduced the accuracy with regard to each tear configuration. Medial meniscal root tears showed a strong association with degenerative joint disease. High grade cartilage defects of the medial femoral condyle and medial meniscal extrusions also

  6. MR Imaging of a Posterior Root Tear of the Medial Meniscus: Diagnostic Accuracy of Various Tear Configurations and Associated Knee Abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyang Mi; Shim, Jae Chan; Kim, Jin Goo; Lee, Jae Myeong; Nam, Mee Young; Lee, Ghi Jai; Kim, Ho Kyun; Suh, Jung Ho [Inje University College of Medicine, Seoul Paik Hospital, Seoul (Korea, Republic of)

    2010-11-15

    To evaluate the diagnostic accuracy of the various tear configurations in a medial meniscal posterior horn root tear and assess whether any correlation exists with other associated knee abnormalities in MR imaging. A retrospective review of 146 preoperative knee MR images were performed by one experienced musculoskeletal radiologist. The tear configuration and other abnormalities were evaluated. Sensitivity, specificity, and diagnostic accuracy of each configuration in the medial meniscal posterior horn root tear were calculated. A total of 48 medial meniscal posterior horn root tears including 38 full-thickness radial, 7 partial-thickness radial, and 3 complex tears were confirmed during arthroscopy. Overall, the sensitivity, specificity, and accuracy for the detection of medial meniscal posterior horn root tear were 92% (44/48), 99% (97/98), and 97% (141/146), respectively. For each tear configuration, sensitivity, specificity, and accuracy were 82% (31/38), 97% (105/108), and 93% (136/146) for full-thickness radial tears, respectively, and 43% (3/7), 94% (131/139), and 91% (134/146) for partial-thickness radial tears, respectively. The incidence of degenerative joint disease was 85% (41/48) for the tear group, revealing a strong association. In patients with a root tear and with degenerative joint disease, the incidence of high grade cartilage defects involving the medial femoral condyle was at 80% (33/41), compared to 56% (23/41) for the presence of medial meniscal extrusion. In contrast, a similar comparison of incidence for patients with no root tears but with degenerative joint disease was at 68% (17/25) and 26% (8/31), respectively. MR imaging is very sensitive for the detection of medial meniscal root tears, but has reduced the accuracy with regard to each tear configuration. Medial meniscal root tears showed a strong association with degenerative joint disease. High grade cartilage defects of the medial femoral condyle and medial meniscal extrusions also

  7. Correlation of histological examination of meniscus with MR images; Focused on high signal intensity of the meniscus not caused by definite meniscal tear and impact on MR diagnosis of tears

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chun Ai; Kim, Min Ki; Kim, In Hwan; Lee, Ju Hong; Jang, Kyu Yun; Lee, Sang Yong [Chonbuk National University Hospital, Chonbuk National University College of Medicine, Jeonju (Korea, Republic of)

    2013-12-15

    To document the causes of high signal intensity of the meniscus which is not caused by definite meniscal tears on MR imaging, through correlation with histological examination. For the correlation between the MR image and histology, we obtained prospectively 31 meniscal specimens from 21 patients. Proton density-weighted turbo spin-echo MR images were used. Minimal tear, thinning of the lamellar layer, degeneration of the central layer, and radial tie fibers were detected upon histological examination, and were correlated with the corresponding MR images. Minimal tear of the lamellar layer was seen in 60 zones out of 100 slides. On MR images, 29 (48.3%) of these 60 zones had high signal intensity. Thinning of the lamellar layer was seen in 24 zones, with 7 (29.2%) having high signal intensity. 57 central zones showed degenerative change in the central layer and high signal intensity on all corresponding MR images. Radial tie fibers in the central layer appeared as high signal intensity areas. Minimal tear and thinning of the lamellar layer, degeneration and radial tie fibers of the central layer of the meniscus cause high signal intensity on MR images.

  8. Diagnostic accuracy of the Thessaly test, standardised clinical history and other clinical examination tests (Apley's, McMurray's and joint line tenderness) for meniscal tears in comparison with magnetic resonance imaging diagnosis.

    Science.gov (United States)

    Blyth, Mark; Anthony, Iain; Francq, Bernard; Brooksbank, Katriona; Downie, Paul; Powell, Andrew; Jones, Bryn; MacLean, Angus; McConnachie, Alex; Norrie, John

    2015-08-01

    Reliable non-invasive diagnosis of meniscal tears is difficult. Magnetic resonance imaging (MRI) is often used but is expensive and incidental findings are problematic. There are a number of physical examination tests for the diagnosis of meniscal tears that are simple, cheap and non-invasive. To determine the diagnostic accuracy of the Thessaly test and to determine if the Thessaly test (alone or in combination with other physical tests) can obviate the need for further investigation by MRI or arthroscopy for patients with a suspected meniscal tear. Single-centre prospective diagnostic accuracy study. Although the study was performed in a secondary care setting, it was designed to replicate the results that would have been achieved in a primary care setting. Two cohorts of patients were recruited: patients with knee pathology (n = 292) and a control cohort with no knee pathology (n = 75). Sensitivity, specificity and diagnostic accuracy of the Thessaly test in determining the presence of meniscal tears. Participants were assessed by both a primary care clinician and a musculoskeletal clinician. Both clinicians performed the Thessaly test, McMurray's test, Apley's test, joint line tenderness test and took a standardised clinical history from the patient. The Thessaly test had a sensitivity of 0.66, a specificity of 0.39 and a diagnostic accuracy of 54% when utilised by primary care clinicians. This compared with a sensitivity of 0.62, a specificity of 0.55 and diagnostic accuracy of 59% when used by musculoskeletal clinicians. The diagnostics accuracy of the other tests when used by primary care clinicians was 54% for McMurray's test, 53% for Apley's test, 54% for the joint line tenderness test and 55% for clinical history. For primary care clinicians, age and past history of osteoarthritis were both significant predictors of MRI diagnosis of meniscal tears. For musculoskeletal clinicians age and a positive diagnosis of meniscal tears on clinical history

  9. Meniscus tears of the knee: Postarthrogram high resolution CT

    International Nuclear Information System (INIS)

    Kim, Jae Hyoung; Do, Young Soo; You, Jin Jong; Gong, Jae Chul; Kim, Hyung Jin; Chung, Sung Hoon

    1990-01-01

    Thirty-eight knees with clinically suspected meniscal tears were examined with high resolution computed tomography(HRCT) immediately following double contrast arthrography. All subsequently underwent arthroscopy. The findings of postarthrogram HRCT and arthroscopy were compared to evaluated the usefulness of postarthrogram HRCT in diagnosis of the meniscal tears. The sensitivity, specificity and accuracy of HRCT were 96.2%. 83.3% and 92.1% respectively. The anatomic details of the meniscal tears were clearly visible on the HRCT scans. Sagittal and coronal reformation views well visualized the horizontal tears and the relationship of torn meniscal fragments, and well differential the peripheral tears from the synovial recess. Our result indicate that postarthrogram HRCT not only is a sensitive and effective method for the detection and characterization of the meniscal tears, but also provides arthroscopists with the appropriate surgical plans

  10. Epidemiology of isolated meniscal injury and its effect on performance in athletes from the National Basketball Association.

    Science.gov (United States)

    Yeh, Peter C; Starkey, Chad; Lombardo, Stephen; Vitti, Gary; Kharrazi, F Daniel

    2012-03-01

    The current incidence and outcomes of meniscal injury have not been quantified in professional athletes. To describe the incidence, risk, amount of time lost, and effect on performance for isolated meniscal injury in athletes from the National Basketball Association (NBA). Demographic factors predicting the risk of meniscal tears and the effect of injury in return to play were also investigated. Descriptive epidemiology study. A centralized database was queried to identify meniscal injuries occurring in the NBA over 21 seasons. The frequency of injury, time lost, game exposures, and incidence, rate, and risk were calculated. The preinjury and postinjury player efficiency rating (PER) was used to identify changes in player performance. We identified 129 isolated meniscal tears in NBA athletes during a 21-season span. From this number, 77 (59.7%) involved the lateral meniscus and 52 (40.3%) the medial meniscus. Injuries occurred more frequently in games. The lateral meniscus had a statistically significant higher injury rate. Both left and right knees were equally affected. The number of days missed for lateral meniscal tears and medial meniscal tears was 43.8 ± 35.7 days and 40.9 ± 29.7 days, respectively, and was not statistically different. There was a significant inverse relationship between age and rate of lateral meniscal tears, with lateral meniscal tears more likely to occur up to age 30 years; beyond that medial meniscal tears were more common. Players with a body mass index (BMI) greater than 25 had a significantly increased risk of meniscal tears compared with players with a BMI less than 25, specifically with an increased risk of lateral meniscal tears. Twenty-five players (19.4%) did not return to play. For those who did, upon returning to competition, there was no statistical change in PER from their preinjury status, and the mean number of seasons completed was 4.1 ± 3.7 seasons. The lateral meniscus is more frequently torn than the medial meniscus

  11. The relationship between chondromalacia patella, medial meniscal tear and medial periarticular bursitis in patients with osteoarthritis

    OpenAIRE

    Resorlu Mustafa; Doner Davut; Karatag Ozan; Toprak Canan Akgun

    2017-01-01

    Abstract Background This study investigated the presence of bursitis in the medial compartment of the knee (pes anserine, semimembranosus-tibial collateral ligament, and medial collateral ligament bursa) in osteoarthritis, chondromalacia patella and medial meniscal tears. Patients and methods Radiological findings of 100 patients undergoing magnetic resonance imaging with a preliminary diagnosis of knee pain were retrospectively evaluated by two radiologists. The first radiologist assessed al...

  12. Success of Meniscal Repair at ACL Reconstruction

    Science.gov (United States)

    Toman, Charles; Spindler, Kurt P.; Dunn, Warren R.; Amendola, Annunziata; Andrish, Jack T.; Bergfeld, John A.; Flanigan, David; Jones, Morgan; Kaeding, Christopher C.; Marx, Robert G.; Matava, Matthew J.; McCarty, Eric C.; Parker, Richard D.; Wolcott, Michelle; Vidal, Armando; Wolf, Brian R.; Huston, Laura J.; Harrell, Frank E.; Wright, Rick W.

    2013-01-01

    Background Meniscal repair is performed in an attempt to prevent posttraumatic arthritis resulting from meniscal dysfunction after meniscal tears. The socioeconomic implications of premature arthritis are significant in the young patient population. Investigations and techniques focusing on meniscus preservation and healing are now at the forefront of orthopaedic sports medicine. Hypothesis Concomitant meniscal repair with ACL reconstruction is a durable and successful procedure at two year follow-up. Study Design Case Series; Level of evidence, 4. Methods All unilateral primary ACL reconstructions entered in 2002 in a prospective cohort who had meniscal repair at the time of ACLR were evaluated. Validated patient oriented outcome instruments were completed preoperatively and then again at the two-year postoperative time point. Reoperation after the index procedure was also documented and confirmed by operative reports. Results 437 unilateral primary ACL reconstructions were performed with 86 concomitant meniscal repairs (57 medial, 29 lateral) in 84 patients during the study period. Patient follow-up was obtained on 94% (81/86) of the meniscal repairs, allowing confirmation of meniscal repair success (defined as no repeat arthroscopic procedure) or failure. The overall success rate for meniscal repairs was 96% (76/79 patients) at two-year follow-up. Conclusions Meniscal repair is a successful procedure in conjunction with ACL reconstruction. When confronted with a “repairable” meniscal tear at the time of ACL reconstruction, orthopaedic surgeons can expect an estimated >90% clinical success rate at two-year follow-up using a variety of methods as shown in our study. PMID:19465734

  13. Analysis of MR imaging with FSE and DESS for the diagnosis of meniscal tears in 316 patients

    International Nuclear Information System (INIS)

    Lee, Jae Gue; Ryu, Kyung Nam; Hong, Hyun Pyo

    1999-01-01

    To evaluate the accuracy of a magnetic resonance(MR) imaging strategy that primarily uses fast spin-echo(SE) sequences for the diagnosis of meniscal tears. The original clinical interpretations of MR images in 316 patients who underwent imaging for suspected internal derangement of a knee joint were correlated with results from subsequent arthroscopy (mean interval:48.9 days). In all patients, MR examinations included double-echo fast SE T2-weighted sagittal and coronal imaging and double-echo steady state (DESS) sequence sagittal imaging. In 199 patients fat-suppressed conventional SE T1-weighted sagittal imaging was used. In cases in which interpretation was erroneous, imaging findings and arthroscopy reports were reviewed. For ISO confirmed tears of the medial meniscus, sensitivity, specificity, and accuracy were 94%, 93%, and 94%, respectively, while respective values for 147 confirmed tears of the lateral meniscus were 85%, 97%, and 91%. These values are within the ranges recently reported for imaging strategies relying predominantly on conventional SE sequences. Of the 12 false-positive tears of the medial meniscus, five menisci showed a high signal contacting the surface on only one image and seven, that in all cases were located in the periphery of the posterior horn, showed such signal on more than one image. Of the six false-positive tears of the lateral meniscus, three menisci showed a high signal contacting the surface on only one image. Of the nine false-negative tears of the medial meniscus, eight menisci showed an abnormal signal that did not demonstrate definitive contact with the surface. Of the 22 false-negative tears of the lateral meniscus, 18 menisci showed this same type of signal. Fast SE imaging of the knee can be an alternative to conventional SE imaging for the detection of meniscal tears. Most errors in our series were due to either an abnormal signal that failed to show definitive contact with the surface, a high signal which contacted

  14. Meniscal pathology in children: differences and similarities with the adult meniscus

    Energy Technology Data Exchange (ETDEWEB)

    Francavilla, Michael L.; Restrepo, Ricardo; Zamora, Kathryn W.; Sarode, Vijaya [Department of Radiology, Miami Children' s Hospital, Miami, FL (United States); Swirsky, Stephen M. [Department of Orthopedics, Miami Children' s Hospital, Miami, FL (United States); Mintz, Douglas [Hospital for Special Surgery, New York, NY (United States)

    2014-08-15

    The normal meniscus undergoes typical developmental changes during childhood, reaching a mature adult appearance by approximately 10 years of age. In addition to recognizing normal meniscal appearances in children, identifying abnormalities - such as tears and the different types of discoid meniscus and meniscal cysts, as well as the surgical implications of these abnormalities - is vital in pediatric imaging. The reported incidence of meniscal tears in adolescents and young adults has increased because of increased sports participation and more widespread use of MRI. This review discusses the normal appearance of the pediatric meniscus, meniscal abnormalities, associated injuries, and prognostic indicators for repair. (orig.)

  15. Meniscal pathology in children: differences and similarities with the adult meniscus

    International Nuclear Information System (INIS)

    Francavilla, Michael L.; Restrepo, Ricardo; Zamora, Kathryn W.; Sarode, Vijaya; Swirsky, Stephen M.; Mintz, Douglas

    2014-01-01

    The normal meniscus undergoes typical developmental changes during childhood, reaching a mature adult appearance by approximately 10 years of age. In addition to recognizing normal meniscal appearances in children, identifying abnormalities - such as tears and the different types of discoid meniscus and meniscal cysts, as well as the surgical implications of these abnormalities - is vital in pediatric imaging. The reported incidence of meniscal tears in adolescents and young adults has increased because of increased sports participation and more widespread use of MRI. This review discusses the normal appearance of the pediatric meniscus, meniscal abnormalities, associated injuries, and prognostic indicators for repair. (orig.)

  16. Integrity of articular cartilage on T2 mapping associated with meniscal signal change

    International Nuclear Information System (INIS)

    Kai, Brian; Mann, Sumeer A.; King, Chris; Forster, Bruce B.

    2011-01-01

    Objective: The purpose of this study was to investigate the relationship between T2 relaxation values (T2 RVs) within the superficial zone of articular cartilage and different types of meniscal degeneration/tear. Materials and methods: A review of 310 consecutive knee MRIs which included an 8 echo T2 relaxation sequence, in patients referred for standard clinical indications, was performed independently and in blinded fashion by 2 observers. The posterior horns of the medial and lateral menisci were each evaluated and divided into 4 subgroups: Normal (control), Grade I/II meniscal signal, Grade III meniscal signal-simple tear (Grade III-S), and Grade III meniscal signal-complex tear (Grade III-C). After exclusion criteria were applied, the medial meniscal group consisted of 65 controls and 133 patients, while the lateral meniscal group consisted of 143 controls and 55 patients. T2 RVs were measured by an observer blinded to the clinical history and MRI grading. Measurements were obtained over the superficial zone of femoral and tibial articular cartilage adjacent to the center of the posterior horn of each meniscus to ensure consistency between measurements. Analysis of covariance adjusting for age and gender was used to compare T2 RVs between patients and controls. Results: T2 RVs were significantly increased in patients with Grade III-C meniscal tears compared to controls over the medial tibial plateau (MTP; p = 0.0001) and lateral tibial plateau (LTP; p = 0.0008). T2 RVs were not increased in patients with Grade III-C meniscal tears over the medial femoral condyle (MFC; p = 0.11) or lateral femoral condyle (LFC; p = 0.99). Grade I/II meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.15), LFC (p = 0.69), MTP (p = 0.42), or LTP (p = 0.50). Grade III-S meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.54), LFC (p = 0.43), MTP (p = 0.30), or LTP (p = 0.38). Conclusion: Grade III-C meniscal tears are associated with

  17. Integrity of articular cartilage on T2 mapping associated with meniscal signal change

    Energy Technology Data Exchange (ETDEWEB)

    Kai, Brian [Department of Radiology, University of British Columbia, UBC Hospital, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5 (Canada); Mann, Sumeer A. [Department of Radiology, University of Alberta, Walter Mackenzie Health Sciences Center, Edmonton, AB, T6G 2B7 (Canada); King, Chris [Department of Radiology, University of British Columbia, UBC Hospital, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5 (Canada); Forster, Bruce B., E-mail: bruce.forster@vch.ca [Department of Radiology, University of British Columbia, UBC Hospital, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5 (Canada)

    2011-09-15

    Objective: The purpose of this study was to investigate the relationship between T2 relaxation values (T2 RVs) within the superficial zone of articular cartilage and different types of meniscal degeneration/tear. Materials and methods: A review of 310 consecutive knee MRIs which included an 8 echo T2 relaxation sequence, in patients referred for standard clinical indications, was performed independently and in blinded fashion by 2 observers. The posterior horns of the medial and lateral menisci were each evaluated and divided into 4 subgroups: Normal (control), Grade I/II meniscal signal, Grade III meniscal signal-simple tear (Grade III-S), and Grade III meniscal signal-complex tear (Grade III-C). After exclusion criteria were applied, the medial meniscal group consisted of 65 controls and 133 patients, while the lateral meniscal group consisted of 143 controls and 55 patients. T2 RVs were measured by an observer blinded to the clinical history and MRI grading. Measurements were obtained over the superficial zone of femoral and tibial articular cartilage adjacent to the center of the posterior horn of each meniscus to ensure consistency between measurements. Analysis of covariance adjusting for age and gender was used to compare T2 RVs between patients and controls. Results: T2 RVs were significantly increased in patients with Grade III-C meniscal tears compared to controls over the medial tibial plateau (MTP; p = 0.0001) and lateral tibial plateau (LTP; p = 0.0008). T2 RVs were not increased in patients with Grade III-C meniscal tears over the medial femoral condyle (MFC; p = 0.11) or lateral femoral condyle (LFC; p = 0.99). Grade I/II meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.15), LFC (p = 0.69), MTP (p = 0.42), or LTP (p = 0.50). Grade III-S meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.54), LFC (p = 0.43), MTP (p = 0.30), or LTP (p = 0.38). Conclusion: Grade III-C meniscal tears are associated with

  18. Trajectory of self-reported pain and function and knee extensor muscle strength in young patients undergoing arthroscopic surgery for meniscal tears: A systematic review and meta-analysis.

    Science.gov (United States)

    Thorlund, Jonas Bloch; Østengaard, Lasse; Cardy, Nathan; Wilson, Fiona; Jørgensen, Claus; Juhl, Carsten Bogh

    2017-08-01

    To investigate the trajectory of patient reported pain and function and knee extensor muscle strength over time in young individuals undergoing arthroscopic meniscal surgery. Systematic review and meta-analysis METHODS: Six databases were searched up to October 13th, 2016. People aged 30 years or younger undergoing surgery for a meniscal tear. and comparator: (1) Self-reported pain and function in patients undergoing meniscal surgery compared to a non-operative control group (2). Knee extensor strength in the leg undergoing surgery compared to a healthy control group or the contra-lateral leg. Methodological quality was assessed using the SIGN 50 guidelines. No studies were found on patient reported pain and function. Six studies, including 137 patients were included in the analysis on knee extensor muscle strength. Knee extensor muscle strength was impaired in the injured leg prior to surgery and was still reduced compared with control data up to 12 months after surgery (SMD: -1.16) (95% CI: -1.83; -0.49). All included studies were assessed to have a high risk of bias. No studies were found comparing the trajectory of self-reported pain and function in patients undergoing arthroscopic surgery compared with non-operative treatments for young patients with meniscal tears. Knee extensor strength seemed to be impaired up to 12 months after surgery in young patients undergoing surgery for meniscal tears. The results of the present study should be interpreted with caution due to a limited number of available studies with high risk of bias including relatively few patients. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  19. Chronic anterior cruciate ligament tears and associated meniscal and traumatic cartilage lesions: evaluation with morphological sequences at 3.0 T

    Energy Technology Data Exchange (ETDEWEB)

    Vlychou, Marianna; Fezoulidis, Ioannis V. [University Hospital of Larissa, Department of Radiology, Medical School of Thessaly, Larissa (Greece); Hantes, Michalis; Michalitsis, Sotirios; Malizos, Konstantinos [University Hospital of Larissa, Department of Orthopaedic Surgery, Medical School of Thessaly, Larissa (Greece); Tsezou, Aspasia [University Hospital of Larissa, Department of Molecular Genetics and Cytogenetics, Medical School of Thessaly, Larissa (Greece)

    2011-06-15

    To investigate the diagnostic efficacy of morphological sequences at 3.0 T MR imaging in detecting anterior cruciate ligament (ACL), meniscal pathology and traumatic cartilage legions in young patients with chronic deficient anterior cruciate ligament knees. This prospective study included 43 patients (39 male) between the age of 15 and 37 years (mean age 22.6 years) with a history of knee injury sustained at least 3 months prior to the decision to repair a torn ACL. All patients underwent a 3.0 T MR scan with the same standard protocol, including intermediate-weighted and three-dimensional spoiled gradient-recalled T1-weighted sequences with fat saturation and subsequently surgical reconstruction of the ACL, along with meniscal and cartilage repair, when necessary. All ACL tears were correctly interpreted by 3.0 T MR images. The sensitivity of the MR scans regarding tears of the medial meniscus was 93.7%, the specificity 92.6%, the positive predictive value 88.2% and the negative predictive value 95.8%. The sensitivity of the MR scans regarding tears of lateral meniscus was 85.7%, the specificity was 93.1%, the positive predictive value 85.7% and the negative predictive value 93.1%. With regard to the grading of the cartilage lesions, Cohen's kappa coefficient indicated moderate agreement for grade I and II cartilage lesions (0.5), substantial agreement for grade III and IV cartilage lesions (0.70 and 0.66) and substantial agreement for normal regions (0.75). Regarding location of the cartilage lesions, Cohen's kappa coefficient varied between almost perfect agreement in the lateral femoral condyle and no agreement in the trochlea. In the setting of chronic ACL deficiency, MR imaging at 3.0 T achieves satisfactory diagnostic performance regarding meniscal and ligamentous pathology. In the detection of cartilage lesions MRI is less successful. (orig.)

  20. Comparison of spin echo T1-weighted sequences versus fast spin-echo proton density-weighted sequences for evaluation of meniscal tears at 1.5 T

    International Nuclear Information System (INIS)

    Wolff, Andrew B.; Pesce, Lorenzo L.; Wu, Jim S.; Smart, L.R.; Medvecky, Michael J.; Haims, Andrew H.

    2009-01-01

    At our institution, fast spin-echo (FSE) proton density (PD) imaging is used to evaluate articular cartilage, while conventional spin-echo (CSE) T1-weighted sequences have been traditionally used to characterize meniscal pathology. We sought to determine if FSE PD-weighted sequences are equivalent to CSE T1-weighted sequences in the detection of meniscal tears, obviating the need to perform both sequences. We retrospectively reviewed the records of knee arthroscopies performed by two arthroscopy-focused surgeons from an academic medical center over a 2-year period. The preoperative MRI images were interpreted independently by two fellowship-trained musculoskeletal radiologists who graded the sagittal CSE T1 and FSE PD sequences at different sittings with grades 1-5, where 1 = normal meniscus, 2 = probable normal meniscus, 3 indeterminate, 4 = probable torn meniscus, and 5 = torn meniscus. Each meniscus was divided into an anterior and posterior half, and these halves were graded separately. Operative findings provided the gold standard. Receiver operating characteristic (ROC) analysis was performed to compare the two sequences. There were 131 tears in 504 meniscal halves. Using ROC analysis, the reader 1 area under curve for FSE PD was significantly better than CSE T1 (0.939 vs. 0.902, >95% confidence). For reader 2, the difference met good criteria for statistical non-inferiority but not superiority (0.913 for FSE PD and 0.908 for CSE T1; >95% non-inferiority for difference at most of -0.027). FSE PD-weighted sequences, using our institutional protocol, are not inferior to CSE T1-weighted sequences for the detection of meniscal tears and may be superior. (orig.)

  1. A new hydrogel for the conservative treatment of meniscal lesions: a randomized controlled study.

    Science.gov (United States)

    Zorzi, Claudio; Rigotti, Stefano; Screpis, Daniele; Giordan, Nicola; Piovan, Gianluca

    2015-01-01

    this study aimed to investigate the efficacy of intra-articular (IA) administration of a hydrogel formulation obtained from a hyaluronic acid (HA) derivative (HYADD4(®)) in the management of meniscal tears and in meniscal tear repair. fifty subjects with degenerative meniscal tears were enrolled into this single-site, observer-blind, parallel-group study. Clinical evaluations were performed at baseline and after 14, 30 and 60 days. Clinical outcomes included: pain reduction (Visual Analog Scale), improvement of knee functionality (WOMAC questionnaire), reduction in length and depth of the meniscal lesion (MRI-confirmed) and SF-36 questionnaire scores. Local tolerability and safety were also investigated. a significant reduction in VAS pain (p< 0.001) in favor of HYADD4(®) was recorded at day 14 and maintained at all the follow-up assessments. Data on knee functionality were in line with the VAS pain assessment results. A significant reduction in length and depth of the meniscal lesion, assessed using MRI, was found in the HYADD4(®) group compared to the control group (p<0.001). the results of this study may indicate a new treatment option in the conservative management of patients complaining of pain due to meniscal tears. The MRI data suggest that the hydrogel formulation of HA used in this study may also play a role in the healing process of the lesion. Level I, prospective randomized clinical trial.

  2. Meniscal injuries in the young, athletically active patient.

    Science.gov (United States)

    Poulsen, Matthew R; Johnson, Darren L

    2011-02-01

    Meniscal injuries are common in young physically active individuals, particularly those who are involved in contact level 1 sports that involve frequent pivoting, such as soccer and American football. This is a unique population because of their high physical activity at a young age, and it is important that correct diagnosis and appropriate treatment are provided, as the medial and lateral menisci are essential for normal knee function. In this article, we review the anatomy and function of the meniscus, the epidemiology of meniscal tears, and mechanism(s) of injury. Important concomitant injuries are also discussed. When making a diagnosis, relevant patient history, physical examination, and appropriate imaging studies are required. Nonoperative treatment is rarely successful for treating meniscal tears in young athletes, and therefore repair of the torn menisci is often required. We also discuss partial resection (which should only be performed when repair is not possible), as well as rehabilitation protocols after repair has been performed. All of these factors associated with meniscal injuries are important for a physician when diagnosing and treating these often complex injuries.

  3. Comparison of Medial and Lateral Meniscus Root Tears.

    Directory of Open Access Journals (Sweden)

    Ji Hyun Koo

    Full Text Available The meniscus root plays an essential role in maintaining the circumferential hoop tension and preventing meniscal displacement. Studies on meniscus root tears have investigated the relationship of osteoarthritis and an anterior cruciate ligament tear. However, few studies have directly compared the medial and lateral root tears. To assess the prevalence of meniscal extrusion and its relationship with clinical features in medial and lateral meniscus root tears, we performed a retrospective review of the magnetic resonance imaging (MRI results of 42 knee patients who had meniscus posterior horn root tears and who had undergone arthroscopic operations. The presence of meniscal extrusion was evaluated and the exact extent was measured from the tibial margin. The results were correlated with arthroscopic findings. Clinical features including patients' ages, joint abnormalities, and previous trauma histories were evaluated. Twenty-two patients had medial meniscus root tears (MMRTs and twenty patients had lateral meniscus root tears (LMRTs. Meniscal extrusion was present in 18 MMRT patients and one LMRT patient. The mean extent of extrusion was 4.2mm (range, 0.6 to 7.8 in the MMRT group and 0.9mm (range, -1.9 to 3.4 in the LMRT group. Five patients with MMRT had a history of trauma, while 19 patients with LMRT had a history of trauma. Three patients with MMRT had anterior cruciate ligament (ACL tears, while 19 patients with LMRT had ACL tears. The mean age of the patients was 52 years (range: 29-71 years and 30 years (range: 14-62 years in the MMRT and LMRT group, respectively. There was a significant correlation between a MMRT and meniscal extrusion (p<0.0001, and between an ACL tear and LMRT (p<0.0001. A history of trauma was significantly common in LMRT (p<0.0001. LMRT patients were significantly younger than MMRT patients (p<0.0001. Kellgren-Lawrence (K-L grade differed significantly between MMRT and LMRT group (p<0.0001. Meniscal extrusion is

  4. Surgical interventions for meniscal tears: a closer look at the evidence

    NARCIS (Netherlands)

    Mutsaerts, Eduard L. A. R.; van Eck, Carola F.; van de Graaf, Victor A.; Doornberg, Job N.; van den Bekerom, Michel P. J.

    2016-01-01

    The aim of the present study was to compare the outcomes of various surgical treatments for meniscal injuries including (1) total and partial meniscectomy; (2) meniscectomy and meniscal repair; (3) meniscectomy and meniscal transplantation; (4) open and arthroscopic meniscectomy and (5) various

  5. Meniscal tear evaluation. Comparison of a conventional spin-echo proton density sequence with a fast spin-echo sequence utilizing a 512x358 matrix size

    International Nuclear Information System (INIS)

    Hopper, M.A.; Robinson, P.; Grainger, A.J.

    2011-01-01

    Aim: To determine the sensitivities, specificities, and receiver-operating characteristics (ROCs) for sagittal conventional spin-echo proton density (SE-PD) and fast spin-echo proton density (FSE-PD) sequences in the diagnosis of meniscal tears when compared to arthroscopic findings utilizing increased FSE matrix acquisition size. Method and materials: Magnetic resonance imaging (MRI) studies of 97 knees (194 menisci) were independently and prospectively interpreted by two experienced musculoskeletal radiologists over four separate readings at least 3 weeks apart. Readings 1 and 2 included images in all three planes in accordance with the standard protocol with either a SE or FSE sagittal PD, at readings 3 and 4 just the SE or FSE sagittal PD sequences were reported. The FSE sequence was acquired with an increased matrix size, compared to the SE sequence, to provide increased resolution. Menisci were graded for the presence of a tear and statistical analysis to calculate sensitivity and specificity was performed comparing to arthroscopy as the reference standard. ROC analysis for the diagnosis of meniscal tears on the SE and FSE sagittal sequences was also evaluated. Reader concordance for the SE and FSE sequences was calculated. Results: Sixty-seven tears were noted at arthroscopy; 60 were detected on SE and 56 on FSE. The sensitivity and specificity for SE was 90 and 90%, and for FSE was 84 and 94%, respectively, with no significant difference. ROC analysis showed no significant difference between the two sequences and kappa values demonstrated a higher level of reader agreement for the FSE than for the SE reading. Conclusion: Use of a FSE sagittal PD sequence with an increased matrix size provides comparable performance to conventional SE sagittal PD when evaluating meniscal disease with a modern system. The present study indicates an increased level of concordance between readers for the FSE sagittal sequence compared to the conventional SE.

  6. Meniscal tear evaluation. Comparison of a conventional spin-echo proton density sequence with a fast spin-echo sequence utilizing a 512x358 matrix size

    Energy Technology Data Exchange (ETDEWEB)

    Hopper, M.A.; Robinson, P. [Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Grainger, A.J., E-mail: andrew.grainger@leedsth.nhs.u [Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom)

    2011-04-15

    Aim: To determine the sensitivities, specificities, and receiver-operating characteristics (ROCs) for sagittal conventional spin-echo proton density (SE-PD) and fast spin-echo proton density (FSE-PD) sequences in the diagnosis of meniscal tears when compared to arthroscopic findings utilizing increased FSE matrix acquisition size. Method and materials: Magnetic resonance imaging (MRI) studies of 97 knees (194 menisci) were independently and prospectively interpreted by two experienced musculoskeletal radiologists over four separate readings at least 3 weeks apart. Readings 1 and 2 included images in all three planes in accordance with the standard protocol with either a SE or FSE sagittal PD, at readings 3 and 4 just the SE or FSE sagittal PD sequences were reported. The FSE sequence was acquired with an increased matrix size, compared to the SE sequence, to provide increased resolution. Menisci were graded for the presence of a tear and statistical analysis to calculate sensitivity and specificity was performed comparing to arthroscopy as the reference standard. ROC analysis for the diagnosis of meniscal tears on the SE and FSE sagittal sequences was also evaluated. Reader concordance for the SE and FSE sequences was calculated. Results: Sixty-seven tears were noted at arthroscopy; 60 were detected on SE and 56 on FSE. The sensitivity and specificity for SE was 90 and 90%, and for FSE was 84 and 94%, respectively, with no significant difference. ROC analysis showed no significant difference between the two sequences and kappa values demonstrated a higher level of reader agreement for the FSE than for the SE reading. Conclusion: Use of a FSE sagittal PD sequence with an increased matrix size provides comparable performance to conventional SE sagittal PD when evaluating meniscal disease with a modern system. The present study indicates an increased level of concordance between readers for the FSE sagittal sequence compared to the conventional SE.

  7. Evaluation of meniscal subluxation of the knee with MR imaging

    International Nuclear Information System (INIS)

    Kim, Hyun Chul; Park, Jin Gyoon; Kang, Heoung Keun; Kim, Jae Kyu; Seo, Jeong Jin; Kim, Yun Hyeon; Chung, Tae Woong

    2000-01-01

    The purpose of this study was to determine the normal meniscal position and meniscal subluxation by means of MR imaging. The normal position of the meniscus was determined by measuring the distance between the peripheral meniscal borders and the tibial plateau, as seen on coronal, sagittal and oblique MR images of 40 normal knees. For 33 abnormal knees in which outward subluxation of the meniscus from the tibial plateau was noted, the involved site, the predisposing factor, and the frequency of meniscus tearing were analyzed. In normal knees, the peripheral border of the meniscus extruded 3mm or less from the peripheral border of the tibial plateau. Among 33 abnormal knees, in which 5mm or more outward subluxation of the meniscus was seen, 19 menisci were medial and 14 were lateral. Among the 19, the body was involved in 12, the anterior horn in six, and the posterior horn in one. With regard to the 14 lateral subluxations, involvement of the posterior horn occurred in ten, of both the body and posterior horn in two, of the anterior horn in one, and of the body in one. The common predisposing factor in medial meniscus subluxation was osteoarthritis, seen in 89% of such cases, and in lateral subluxation, anterior cruciate ligament tear, which occurred in 79% of cases. Medial meniscus tear was noted in 89% of medial meniscus subluxations and lateral meniscus tear in 43% of lateral subluxations. Meniscal subluxation was easily detected by MR imaging of the knee. The common predisposing factor in medial meniscus subluxation was osteoarthritis, and in lateral meniscus subluxation, anterior cruciate ligament tear. A torn meniscus frequently co-occurred

  8. Meniscal repair devices.

    Science.gov (United States)

    Barber, F A; Herbert, M A

    2000-09-01

    Meniscal repair devices not requiring accessory incisions are attractive. Many factors contribute to their clinical effectiveness including their biomechanical characteristics. This study compared several new meniscal repair devices with standard meniscal suture techniques. Using a porcine model, axis-of-insertion loads were applied to various meniscal sutures and repair devices. A single device or stitch was placed in a created meniscal tear and a load applied. Both loads and modes of failure were recorded. The load-to-failure data show stratification into 4 distinct statistical groups. Group A, 113 N for a double vertical stitch; group B, 80 N for a single vertical stitch; group C, 57 N for the BioStinger, 56 N for a horizontal mattress stitch, and 50 N for the T-Fix stitch; and group D, 33 N for the Meniscus Arrow (inserted by hand or gun), 32 N for the Clearfix screw, 31 N for the SDsorb staple, 30 N for the Mitek meniscal repair system, and 27 N for the Biomet staple. The failure mechanism varied. Sutures broke away from the knot. The Meniscus Arrow and BioStinger pulled through the inner rim with the crossbar intact. The Clearfix screw failed by multiple mechanisms, whereas 1 leg of the SDsorb staple always pulled out of the outer rim. The Mitek device usually failed by pullout from the inner rim. The Biomet staple always broke at the crosshead or just below it. Although the surgeon should be aware of the material properties of the repair technique chosen for a meniscal repair, this information is only an indication of device performance and may not correlate with clinical healing results.

  9. A Special Tear Pattern of Anterior Horn of the Lateral Meniscus: Macerated Tear.

    Science.gov (United States)

    Zheng, Jiapeng; Zhai, Wenliang; Li, Qiang; Jia, Qianxin; Lin, Dasheng

    2017-01-01

    We describe a special, interesting phenomenon found in the anterior horn of the lateral meniscus (AHLM): most tear patterns in the AHLM are distinctive, with loose fibers in injured region and circumferential fiber bundles were separated. We name it as macerated tear. The goal of this study was to bring forward a new type of meniscal tear in the AHLM and investigate its clinical value. AHLM tears underwent arthroscopic surgery from January 2012 to December 2014 were included. Data regarding the integrity of AHLM were prospectively recorded in a data registry. Tear morphology and treatment received were subsequently extracted by 2 independent reviewers from operative notes and arthroscopic surgical photos. A total of 60 AHLM tears in 60 patients (mean age 27.1 years) were grouped into horizontal tears (n = 15, 25%), vertical tears (n = 14, 23%), complex tears (n = 6, 10%), and macerated tears (n = 25, 42%). There were 6 patients with AHLM cysts in macerated tear group and one patient in vertical tear group. 60 patients were performed arthroscopic meniscus repairs and were followed-up with averaged 18.7 months. Each group had significant postoperative improvement in Lysholm and IKDC scores (p 0.05). This study demonstrated that the macerated tear is common in the tear pattern of AHLM. However, feasibility of the treatment of this type of meniscal tear, especially the meniscus repairs still requires further study.

  10. Quantifying peri-meniscal synovitis and its relationship to meniscal pathology in osteoarthritis of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Grainger, Andrew J. [Leeds General Infirmary, Department of Radiology, Leeds (United Kingdom); Rhodes, Laura A. [Leeds General Infirmary, Academic Unit of Medical Physics, The University of Leeds, Leeds (United Kingdom); Keenan, Anne-Maree; Emery, Paul; Conaghan, Philip G. [Leeds General Infirmary, Academic Unit of Musculoskeletal Disease, Leeds (United Kingdom)

    2007-01-15

    The objectives of this study were to validate a semiquantitative scoring system for estimating perimeniscal synovitis in osteoarthritic (OA) knees and to examine the relationship between the extent of synovitis and the degree of meniscal pathology using gadolinium-enhanced magnetic resonance imaging (MRI). Forty-three subjects with clinically diagnosed OA knee were assessed for peri-meniscal synovitis using gadolinium-enhanced MRI. Quantitative measurements of synovitis were made by summing areas in consecutive slices within generated regions of interest, and the synovitis was also scored semi-quantitatively using a 0-3 scale. Meniscal pathology (extrusion, degeneration and tearing) was also scored semiquantitatively. Establishment of a correlative relationship was undertaken using Spearman's rho ({rho}). A total of 86 sites were assessed. The semi-quantitative synovitis score correlated well with the quantitative synovitis score ({rho}>0.9). A moderate association between medial meniscal extrusion and synovitis was demonstrated ({rho}=0.762, P<0.000), although this association was not as strong in the lateral compartment ({rho}=0.524, P<0.000). The results suggest the semiquantitative scoring system is valid for assessing perimeniscal synovitis. The relationship between meniscal pathology and adjacent synovitis requires further study. (orig.)

  11. Successful anterior cruciate ligament reconstruction and meniscal repair in osteogenesis imperfecta.

    Science.gov (United States)

    Park, Jae-Young; Cho, Tae-Joon; Lee, Myung Chul; Han, Hyuk-Soo

    2018-03-20

    A case of anterior cruciate ligament (ACL) reconstruction with meniscal repair in an osteogenesis imperfecta patient is reported. A 24-year-old female with osteogenesis imperfecta type 1a suffered from a valgus extension injury resulting in tear of ACL and medial meniscus. She underwent an arthroscopic-assisted ACL reconstruction and medial meniscus repair. Meniscal tear at the menisco-capsular junction of the posterior horn of medial meniscus was repaired with three absorbable sutures via inside-out technique. ACL reconstruction was then performed with a bone-patellar tendon-bone allograft. The patient was followed up for 1 year with intact ACL grafts and healed medial meniscus. This case report showed that successful ACL reconstruction and meniscal repair is possible in an osteogenesis imperfecta patient.Level of evidence V.

  12. Structural pathology is not related to patient-reported pain and function in patients undergoing meniscal surgery

    DEFF Research Database (Denmark)

    Christensen, Simon Tornbjerg; Nissen, Nis; Englund, Martin

    2017-01-01

    BACKGROUND: The relationship between meniscal tears and other joint pathologies with patient-reported symptoms is not clear. We investigated associations between structural knee pathologies identified at surgery with preoperative knee pain and function in patients undergoing arthroscopic meniscal...... of meniscal tears questionnaire, supplemented with information extracted from surgery reports. Following hypothesis-driven preselection of candidate variables, backward elimination regressions were performed to investigate associations between patient-reported outcomes and structural knee pathologies. RESULTS...... surgery. METHODS: This study included 443 patients from the Knee Arthroscopy Cohort Southern Denmark (KACS), a prospective cohort following patients 18 years or older undergoing arthroscopic meniscal surgery at 4 hospitals between 1 February 2013 and 31 January 2014. Patient-reported outcomes, including...

  13. Medial meniscal posterior root/horn radial tears correlate with cartilage degeneration detected by T1ρ relaxation mapping

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Kenji, E-mail: Kenji-am@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Hashimoto, Sanshiro, E-mail: info@msorc.jp [Minami-Shinjuku Orthopaedic Rehabilitation Clinic, 2-16-7 Yoyogi, Shibuya-ku, Tokyo 151-0053 (Japan); Nakamura, Hiroshi, E-mail: nakamura@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Mori, Atsushi, E-mail: atsu@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Sato, Akiko, E-mail: akiko-sato@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan); Majima, Tokifumi, E-mail: tkmajima@iuhw.ac.jp [Department of Orthopaedic Surgery, International University of Health and Welfare Hospital, 537-3 Iguchi, Nasu-shiobara, Tochigi 329-2763 (Japan); Takai, Shinro, E-mail: takai-snr@nms.ac.jp [Department of Orthopaedic Surgery, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8603 (Japan)

    2015-06-15

    Highlights: • Posterior radial tears in medial meniscus associate T1ρ values of cartilage. • Posterior radial tears relate to cartilage degeneration even in early-stage osteoarthritis. • Abnormalities in meniscus on MRI are useful for screening early-stage osteoarthritis. - Abstract: Objective: This study aimed to identify factors on routine pulse sequence MRI associated with cartilage degeneration observed on T1ρ relaxation mapping. Materials and methods: This study included 137 subjects with knee pain. T1ρ values were measured in the regions of interest on the surface layer of the cartilage on mid-coronal images of the femorotibial joint. Assessment of cartilage, subchondral bone, meniscus and ligaments was performed using routine pulse sequence MRI. Radiographic evaluation for osteoarthritis was also performed. Results: Multiple regression analysis revealed posterior root/horn tears to be independent factors increasing the T1ρ values of the cartilage in the medial compartment of the femorotibial joint. Even when adjusted for radiographically defined early-stage osteoarthritis, medial posterior meniscal radial tears significantly increased the T1ρ values. Conclusions: This study showed that posterior root/horn radial tears in the medial meniscus are particularly important MRI findings associated with cartilage degeneration observed on T1ρ relaxation mapping. Morphological factors of the medial meniscus on MRI provide findings useful for screening early-stage osteoarthritis.

  14. Medial meniscal posterior root/horn radial tears correlate with cartilage degeneration detected by T1ρ relaxation mapping

    International Nuclear Information System (INIS)

    Takahashi, Kenji; Hashimoto, Sanshiro; Nakamura, Hiroshi; Mori, Atsushi; Sato, Akiko; Majima, Tokifumi; Takai, Shinro

    2015-01-01

    Highlights: • Posterior radial tears in medial meniscus associate T1ρ values of cartilage. • Posterior radial tears relate to cartilage degeneration even in early-stage osteoarthritis. • Abnormalities in meniscus on MRI are useful for screening early-stage osteoarthritis. - Abstract: Objective: This study aimed to identify factors on routine pulse sequence MRI associated with cartilage degeneration observed on T1ρ relaxation mapping. Materials and methods: This study included 137 subjects with knee pain. T1ρ values were measured in the regions of interest on the surface layer of the cartilage on mid-coronal images of the femorotibial joint. Assessment of cartilage, subchondral bone, meniscus and ligaments was performed using routine pulse sequence MRI. Radiographic evaluation for osteoarthritis was also performed. Results: Multiple regression analysis revealed posterior root/horn tears to be independent factors increasing the T1ρ values of the cartilage in the medial compartment of the femorotibial joint. Even when adjusted for radiographically defined early-stage osteoarthritis, medial posterior meniscal radial tears significantly increased the T1ρ values. Conclusions: This study showed that posterior root/horn radial tears in the medial meniscus are particularly important MRI findings associated with cartilage degeneration observed on T1ρ relaxation mapping. Morphological factors of the medial meniscus on MRI provide findings useful for screening early-stage osteoarthritis

  15. Meniscal abnormalities in soccer players: prevalence and MR imaging

    International Nuclear Information System (INIS)

    Song, In Sup; Lee, Jong Ik; Kwak, Byeung Kook; Shim, Hyung Jin; Lee, Jong Beum; Lee, Yong Chul; Kim, Kun Sang; Seo, Kyung Mook

    1995-01-01

    We aimed to know the prevalence of abnormal meniscal signal on MR imaging in asymptomatic soccer players and its radiologic significance. Using T1 and gradient echo T2 weighted sagittal and coronal MR image, 48 knees in twenty-four full time soccer players were evaluated for the meniscal abnormalities, the status of ligament and existence of joint effusion. Meniscal abnormalities were interpreted using grading system of Lotysch. By using Chi-square method. We analyzed the existence of joint effusion could divide the healing state and healed state of the meniscus. The prevalence of Grade 2 and more and Grade 3 were 42% and 39% of asymptomatic knees. In the 24 knees with meniscus tear, nine of the 14 asymptomatic knee showed effusion while eight of the 10 symptomatic knee did. Of 24 knees with meniscal tear, only eleven knees were related to previous history of major knee trauma. The prevalence of meniscal abnormalities on MR imaging in asymptomatic soccer players was higher (grade 3: 39%) than we expected. The joint effusion was not helpful to divide the healing state and healed state of the meniscus. So we suggest baseline MR imaging in the athletes who have been using the knee vigorously could give decisive information for the interpretation of subsequent MRI that may be performed when the players wounded

  16. Snapping Knee Caused by Medial Meniscal Cyst

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Ohishi

    2014-01-01

    Full Text Available Snapping phenomenon around the medial aspect of the knee is rare. We present this case of snapping knee caused by the sartorius muscle over a large medial meniscal cyst in a 66-year-old female. Magnetic resonance images demonstrated a large medial meniscal cyst with a horizontal tear of the medial meniscus. Arthroscopic cyst decompression with limited meniscectomy resulted in the disappearance of snapping, and no recurrence of the cyst was observed during a 2-year follow-up period.

  17. Detection of meniscal injuries using MR imaging

    International Nuclear Information System (INIS)

    Lotysch, M.; Mink, J.H.; Levy, T.; Schwartz, A.; Crues, J.V. III.

    1986-01-01

    Eighty-six knees studied by MR imaging were treated operatively and the surgical-radiologic conditions were reviewed using the following grading system of meniscal signal: grade 1, globular signal within the meniscus that does not involve an articular margin; grade 2, linear signal within the meniscus that does not extend to an articular surface; grade 3, linear or globular signal extending to an articular surface. This grading system was applied to evaluate 86 knees (172 menisci). Eleven menisci had been treated operatively at an earlier period and were excluded. Of 92 grade 1 or 2 menisci, 88 were normal at surgery. Of 69 grade 3 minisci, lesions were associated with meniscal tears in 68 at surgery. MR imaging is an accurate method of evaluating meniscal surgery

  18. Value of modern sonography in the assessment of meniscal lesions

    International Nuclear Information System (INIS)

    Wareluk, Pawel; Szopinski, Kazimierz T.

    2012-01-01

    The aim of this prospective study was to assess the accuracy of modern ultrasonography in diagnostic imaging of meniscal tears. One hundred and sixty menisci were evaluated in 80 patients (42 females, 38 males, mean age = 36.2 years, range = 16–70 years). Inclusion criteria for the study were twofold: clinical suspicion of meniscal injury and clinical indication for arthroscopy. Knee examination was performed with the Voluson 730 Expert ultrasound system (General Electric). After sonographic examination, all patients underwent arthroscopic procedures within 1–4 days. The final diagnosis of meniscal tears was taken from surgical reports. The overall sensitivity, specificity, positive predictive value and negative predictive value of sonographic examination in the assessment of meniscal tears amounted to 85.4%, 85.7%, 67.3% and 94.4%, respectively. The statistical parameters were not statistically different in medial and lateral menisci. Age, sex, body mass index (BMI), weight, physical activity, mechanism on injury, and time lapse from injury did not have a statistically significant impact on the usefulness of ultrasonography. The highest sensitivity (>90%) was obtained in medial menisci and in patients with a BMI > 25. The highest specificity (>90%) was obtained in lateral menisci, in patients after twisting injuries, in sports injuries, and in recent injuries (time lapse from the injury <1 month). The positive predictive value (PPV) of sonographic examination was higher than 90% only in recent injuries (<1 month), however, the negative predictive value of ultrasound is high, being less than 90% in males with lesions of lateral menisci and in sequelae of sports injuries

  19. Value of modern sonography in the assessment of meniscal lesions

    Energy Technology Data Exchange (ETDEWEB)

    Wareluk, Pawel, E-mail: pwareluk@wum.edu.pl [Department of Diagnostic Imaging, Second Faculty of Medicine, Medical University of Warsaw, ul. Kondratowicza 8, 03-242 Warsaw (Poland); Szopinski, Kazimierz T., E-mail: kszopinski@wum.edu.pl [Department of Dental and Maxillofacial Radiology, First Faculty of Medicine, Medical University of Warsaw, ul. Nowogrodzka 59, 02-006 Warsaw (Poland)

    2012-09-15

    The aim of this prospective study was to assess the accuracy of modern ultrasonography in diagnostic imaging of meniscal tears. One hundred and sixty menisci were evaluated in 80 patients (42 females, 38 males, mean age = 36.2 years, range = 16–70 years). Inclusion criteria for the study were twofold: clinical suspicion of meniscal injury and clinical indication for arthroscopy. Knee examination was performed with the Voluson 730 Expert ultrasound system (General Electric). After sonographic examination, all patients underwent arthroscopic procedures within 1–4 days. The final diagnosis of meniscal tears was taken from surgical reports. The overall sensitivity, specificity, positive predictive value and negative predictive value of sonographic examination in the assessment of meniscal tears amounted to 85.4%, 85.7%, 67.3% and 94.4%, respectively. The statistical parameters were not statistically different in medial and lateral menisci. Age, sex, body mass index (BMI), weight, physical activity, mechanism on injury, and time lapse from injury did not have a statistically significant impact on the usefulness of ultrasonography. The highest sensitivity (>90%) was obtained in medial menisci and in patients with a BMI > 25. The highest specificity (>90%) was obtained in lateral menisci, in patients after twisting injuries, in sports injuries, and in recent injuries (time lapse from the injury <1 month). The positive predictive value (PPV) of sonographic examination was higher than 90% only in recent injuries (<1 month), however, the negative predictive value of ultrasound is high, being less than 90% in males with lesions of lateral menisci and in sequelae of sports injuries.

  20. Cost effectiveness of meniscal allograft for torn discoid lateral meniscus in young women.

    Science.gov (United States)

    Ramme, Austin J; Strauss, Eric J; Jazrawi, Laith; Gold, Heather T

    2016-09-01

    A discoid meniscus is more prone to tears than a normal meniscus. Patients with a torn discoid lateral meniscus are at increased risk for early onset osteoarthritis requiring total knee arthroplasty (TKA). Optimal management for this condition is controversial given the up-front cost difference between the two treatment options: the more expensive meniscal allograft transplantation compared with standard partial meniscectomy. We hypothesize that meniscal allograft transplantation following excision of a torn discoid lateral meniscus is more cost-effective compared with partial meniscectomy alone because allografts will extend the time to TKA. A decision analytic Markov model was created to compare the cost effectiveness of two treatments for symptomatic, torn discoid lateral meniscus: meniscal allograft and partial meniscectomy. Probability estimates and event rates were derived from the scientific literature, and costs and benefits were discounted by 3%. One-way sensitivity analyses were performed to test model robustness. Over 25 years, the partial meniscectomy strategy cost $10,430, whereas meniscal allograft cost on average $4040 more, at $14,470. Partial meniscectomy postponed TKA an average of 12.5 years, compared with 17.30 years for meniscal allograft, an increase of 4.8 years. Allograft cost $842 per-year-gained in time to TKA. Meniscal allografts have been shown to reduce pain and improve function in patients with discoid lateral meniscus tears. Though more costly, meniscal allografts may be more effective than partial meniscectomy in delaying TKA in this model. Additional future long term clinical studies will provide more insight into optimal surgical options.

  1. Effectiveness and biocompatibility of a novel biological adhesive application for repair of meniscal tear on the avascular zone

    Science.gov (United States)

    Inoue, Takahito; Taguchi, Tetsushi; Imade, Shinji; Kumahashi, Nobuyuki; Uchio, Yuji

    2012-12-01

    We have investigated the effectiveness and safety of a newly developed biological adhesive for repair of meniscal tear. The adhesive was composed of disuccinimidyl tartrate (DST) as a crosslinker and human serum albumin (HSA) as a hardener. To determine adequate concentration, bonding strength was measured using a tensiometer 5 min after applying the adhesive on the avascular zone tear of porcine meniscus; it was compared with the strengths of commercially available cyanoacrylate-based and fibrin-based adhesives. In vivo examination was performed using Japanese white rabbits, creating longitudinal tears on the avascular zone of meniscus and applying DST-HSA adhesive. Three months after operation the rabbits were sacrificed and tension test and histological evaluation were performed. Bonding strength was measured in three porcine meniscus groups: (i) only suturing, (ii) suturing after applying the adhesive on surface and (iii) suturing using an adhesive-soaked suture. The optimum concentrations were 0.1 mmol of DST and 42 w/v% of HAS. Bonding strength was greatest with cyanoacrylate-based adhesive, followed by DST-HSA adhesive, and fibrin-based adhesive. No inflammation was observed in the synovium or surrounding tissues 3 months after using the DST-HSA adhesive. Bonding strength was greatest with DST-HSA adhesive-soaked suturing group (77 ± 6 N), followed by suturing only group (61 ± 5 N) and surface adhesive application group (60 ± 8 N). The newly developed DST-HSA adhesive is considered safe and may be effective in enforcement of bonding of avascular zone tear of the meniscus.

  2. Meniscal and cruciate ligaments tears diagnosed with MR imaging versus arthroscopy

    International Nuclear Information System (INIS)

    Ziemianski, A.; Kruczynski, J.; Bruszewski, J.

    1993-01-01

    MR studies of knee joints in 37 patients were performed. The clinical diagnostics was traumatic lesions of menisci or cruciate ligaments. Arthroscopy of the knee joint was performed in 21 patients. MR showed meniscal lesion in 25 patients and anterior cruciate ligament (ACL) lesions in 18 patients. Arthroscopy showed meniscal lesions in 16 of 21 patients and ACL lesions in 11 of 21 patients. MR correlated with arthroscopy in 16 of examined menisci and 15 of 21 examined ACL. (author)

  3. MR imaging of the injured meniscus of the knee

    International Nuclear Information System (INIS)

    Sakai, Naotaka; Imamura, Kiyohiko; Uematsu, Koichi; Iwamura, Yuichi; Ohniwa, Hideo; Ishii, Masayoshi

    1992-01-01

    MR imagings (0.5 Tesla 5 mm slice, TR/TE: 510-620 msec/27-30) of the injured menisci in 38 knees of 38 patients (28 men and 10 women, with an average age of 25.9) were compared with their arthroscopic findings and classified into two types, the one with linear high-density area and the non-linear one. Menisci with longitudinal tears in 10 knees of 17 and with horizontal tears in 4 of 8 showed a linear high-density area in MRI, but the others including menisci with transverse tears (in 8 knees) or bucket-handle tears (in 7 knees) showed a non-linear high density area. These results may be due to both the angle between the tear and the slice lines of MR imaging, and the degeneration of menisci. The MRI of normal menisci in 10 knees were also investigated. A false-positive high-density area was often seen at the synovia-meniscal junction in the coronal plane of MR imaging and was seen at the posterior or anterior menisci in the saggital plane. (author)

  4. Meniscal transplantation: still experimental surgery? A review.

    Science.gov (United States)

    Moens, K; Dhollander, A; Moens, P; Verdonk, K; Verdonk, R; Almqvist, K F; Victor, J

    2014-09-01

    The objective of this review is to give a state of affairs of meniscal transplantation, with the accent on preservation and surgical techniques. All articles were selected by performing a search on the literature by using relevant keywords. The most relevant articles were selected with close attention to the publication date. When a meniscal tear is diagnosed, suture can be an option in the vascular zone, whereas the more frequently affected avascular zone heals poorly. A meniscectomy however is not without consequences, wherefore meniscal transplantation can be seen as a therapeutic option for pain reduction and improvement of function when the meniscus is lost. The meniscal scaffold, allograft and autograft can be currently withheld as possible grafts, where the meniscal scaffolds hold great promise as an alternative to the allograft. Various fixation techniques are therefore developed, where viable, deep frozen as well as cryopreservated allografts seem to give the most promising short term results. The transplantation can be performed using an open as well as an arthroscopic technique, using soft tissue fixation, bone plugs or blocks. De primacy of one technique can't be proven. In general meniscal transplantation can be considered as an acceptable procedure. Since the outcomes of different studies are difficult to compare, an attempt should be made to limit new studies to the comparison of one aspect. We can conclude that larger, more comparative randomised controlled long-term studies are necessary to resolve which techniques can give the best long-term results.

  5. The meniscus tear. State of the art of rehabilitation protocols related to surgical procedures.

    Science.gov (United States)

    Frizziero, Antonio; Ferrari, Raffaello; Giannotti, Erika; Ferroni, Costanza; Poli, Patrizia; Masiero, Stefano

    2012-10-01

    Meniscal injuries represent one of the most frequent lesions in sport practicing and in particular in soccer players and skiers. Pain, functional limitation and swelling are typical symptoms associated with meniscal tears. Epidemiological studies showed that all meniscal lesions, in different sports athletes, involves 24% of medial meniscus, while 8% of lateral meniscus and about 20-30% of meniscal lesions are associated with other ligament injuries. Meniscal tears can be treated conservatively or surgically. Surgery leads in many cases to complete resolution of symptoms and allows the return to sport activity. However many studies show that this treatment can induce more frequently the development of degenerative conditions if not correctly associated to a specific rehabilitation protocol. The aim of this article is to compare different timing in specific rehabilitation programs related to the most actual surgical options.

  6. Relationship between years in the trade and the development of radiographic knee osteoarthritis and MRI-detected meniscal tears and bursitis in floor layers. A cross-sectional study of a historical cohort

    DEFF Research Database (Denmark)

    Jensen, Lilli Kirkeskov; Rytter, Søren; Marott, Jacob Louis

    2012-01-01

    An increased risk of developing knee disorders including radiographic knee osteoarthritis (OA) have been shown among workers with kneeling working demands. There may also be a dose-related association between duration of employment in occupations with kneeling work and development of radiographic...... knee OA and magnetic resonance imaging (MRI)-detected meniscal tears and bursitis....

  7. Arthroscopic partial medial meniscectomy

    Directory of Open Access Journals (Sweden)

    Dašić Žarko

    2011-01-01

    Full Text Available Background/Aim. Meniscal injuries are common in professional or recreational sports as well as in daily activities. If meniscal lesions lead to physical impairment they usually require surgical treatment. Arthroscopic treatment of meniscal injuries is one of the most often performed orthopedic operative procedures. Methods. The study analyzed the results of arthroscopic partial medial meniscectomy in 213 patients in a 24-month period, from 2006, to 2008. Results. In our series of arthroscopically treated medial meniscus tears we noted 78 (36.62% vertical complete bucket handle lesions, 19 (8.92% vertical incomplete lesions, 18 (8.45% longitudinal tears, 35 (16.43% oblique tears, 18 (8.45% complex degenerative lesions, 17 (7.98% radial lesions and 28 (13.14% horisontal lesions. Mean preoperative International Knee Documentation Committee (IKDC score was 49.81%, 1 month after the arthroscopic partial medial meniscectomy the mean IKDC score was 84.08%, and 6 months after mean IKDC score was 90.36%. Six months after the procedure 197 (92.49% of patients had good or excellent subjective postoperative clinical outcomes, while 14 (6.57% patients subjectively did not notice a significant improvement after the intervention, and 2 (0.93% patients had no subjective improvement after the partial medial meniscectomy at all. Conclusion. Arthroscopic partial medial meniscetomy is minimally invasive diagnostic and therapeutic procedure and in well selected cases is a method of choice for treatment of medial meniscus injuries when repair techniques are not a viable option. It has small rate of complications, low morbidity and fast rehabilitation.

  8. Changes in Contact Area in Meniscus Horizontal Cleavage Tears Subjected to Repair and Resection.

    Science.gov (United States)

    Beamer, Brandon S; Walley, Kempland C; Okajima, Stephen; Manoukian, Ohan S; Perez-Viloria, Miguel; DeAngelis, Joseph P; Ramappa, Arun J; Nazarian, Ara

    2017-03-01

    To assess the changes in tibiofemoral contact pressure and contact area in human knees with a horizontal cleavage tear before and after treatment. Ten human cadaveric knees were tested. Pressure sensors were placed under the medial meniscus and the knees were loaded at twice the body weight for 20 cycles at 0°, 10°, and 20° of flexion. Contact area and pressure were recorded for the intact meniscus, the meniscus with a horizontal cleavage tear, after meniscal repair, after partial meniscectomy (single leaflet), and after subtotal meniscectomy (double leaflet). The presence of a horizontal cleavage tear significantly increased average peak contact pressure and reduced effective average tibiofemoral contact area at all flexion angles tested compared with the intact state (P contact pressure after creation of the horizontal cleavage tear. Repairing the horizontal cleavage tear restored peak contact pressures and areas to within 15% of baseline, statistically similar to the intact state at all angles tested (P contact pressure and reduced average contact area at all degrees of flexion compared with the intact state (P contact area and a significant elevation in contact pressure. These changes may accelerate joint degeneration. A suture-based repair of these horizontal cleavage tears returns the contact area and contact pressure to nearly normal, whereas both partial and subtotal meniscectomy lead to significant reductions in contact area and significant elevations in contact pressure within the knee. Repairing horizontal cleavage tears may lead to improved clinical outcomes by preserving meniscal tissue and the meniscal function. Understanding contact area and peak contact pressure resulting from differing strategies for treating horizontal cleavage tears will allow the surgeon to evaluate the best strategy for treating his or her patients who present with this meniscal pathology. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier

  9. Repair of Avascular Meniscus Tears with Electrospun Collagen Scaffolds Seeded with Human Cells.

    Science.gov (United States)

    Baek, Jihye; Sovani, Sujata; Glembotski, Nicholas E; Du, Jiang; Jin, Sungho; Grogan, Shawn P; D'Lima, Darryl D

    2016-03-01

    The self-healing capacity of an injured meniscus is limited to the vascularized regions and is especially challenging in the inner avascular regions. As such, we investigated the use of human meniscus cell-seeded electrospun (ES) collagen type I scaffolds to produce meniscal tissue and explored whether these cell-seeded scaffolds can be implanted to repair defects created in meniscal avascular tissue explants. Human meniscal cells (derived from vascular and avascular meniscal tissue) were seeded on ES scaffolds and cultured. Constructs were evaluated for cell viability, gene expression, and mechanical properties. To determine potential for repair of meniscal defects, human meniscus avascular cells were seeded and cultured on aligned ES collagen scaffolds for 4 weeks before implantation. Surgical defects resembling "longitudinal tears" were created in the avascular zone of bovine meniscus and implanted with cell-seeded collagen scaffolds and cultured for 3 weeks. Tissue regeneration and integration were evaluated by histology, immunohistochemistry, mechanical testing, and magentic resonance imaging. Ex vivo implantation with cell-seeded collagen scaffolds resulted in neotissue that was significantly better integrated with the native tissue than acellular collagen scaffolds or untreated defects. Human meniscal cell-seeded ES collagen scaffolds may therefore be useful in facilitating meniscal repair of avascular meniscus tears.

  10. Meniscotibial (coronary) ligament tears

    International Nuclear Information System (INIS)

    El-Khoury, G.Y.; Usta, H.Y.; Berger, R.A.

    1984-01-01

    Preservation of the meniscus whenever possible is essential in maintaining knee stability and preventing premature osteoarthritis. Peripheral meniscal tears are the most amenable to surgical repair. This study evaluates the peripheral attachments of the medial meniscus and focuses on a specific tear limited to the meniscotibial ligament (coronary ligament). The diagnosis is made arthrographically when the medial meniscus floats above the tibial plateau without separating completely from the capsule. The lateral meniscus is rarely involved in this type of injury. (orig.)

  11. MR imaging of anterior cruciate ligament tears: is there a gender gap?

    International Nuclear Information System (INIS)

    Fayad, Laura M.; Parellada, J.Antoni; Parker, Laurence; Schweitzer, Mark E.

    2003-01-01

    Clinically, females receive anterior cruciate ligament (ACL) tears more commonly than males. We explored whether gender differences exist in MR imaging patterns of ACL tears. At 1.5T, two observers evaluated MR examinations of 84 consecutive age-matched patients (42 males, 42 females, aged 16-39) with ACL tears, for mechanism of injury, extent and type of tear, the presence of secondary signs and associated osseous, meniscal and ligamentous injuries. The most common mechanism of injury for both females and males was the pivot shift mechanism (67 and 60%, respectively). Females were more commonly imaged in the acute stage of tear than males (98 and 67%, respectively, p=0.001) and more commonly possessed the typical posterolateral tibial bone contusion pattern (88 and 62%, respectively, p=0.0131). Males exhibited a deeper femoral notch sign (2.7 and 2.0 mm, p=0.007) and medial meniscal, lateral collateral ligament and posterior cruciate ligament injuries more commonly than females (48 and 24%, p=0.009, 30 and 7%, p=0.035, 17 and 0%, p=0.035). There was no significant difference between genders for the presence of other secondary signs and contusion patterns, associated lateral meniscal tears, presence of O'Donoghue's triad or associated medial collateral ligament injuries. Gender differences in MR imaging patterns of ACL tears exist: females are more commonly imaged in the acute stage and more commonly possess posterolateral tibial bone contusions; males have a more severe presentation than females, associated with more severe lateral femoral condyle and soft tissue injuries. (orig.)

  12. Meniscal Tear Film Fluid Dynamics Near Marx’s Line

    KAUST Repository

    Zubkov, V. S.

    2013-07-03

    Extensive studies have explored the dynamics of the ocular surface fluid, though theoretical investigations are typically limited to the use of the lubrication approximation, which is not guaranteed to be uniformly valid a-priori throughout the tear meniscus. However, resolving tear film behaviour within the meniscus and especially its apices is required to characterise the flow dynamics where the tear film is especially thin, and thus most susceptible to evaporatively induced hyperosmolarity and subsequent epithelial damage. Hence, we have explored the accuracy of the standard lubrication approximation for the tear film by explicit comparisons with the 2D Navier-Stokes model, considering both stationary and moving eyelids. Our results demonstrate that the lubrication model is qualitatively accurate except in the vicinity of the eyelids. In particular, and in contrast to lubrication theory, the solution of the full Navier-Stokes equations predict a distinct absence of fluid flow, and thus convective mixing in the region adjacent to the tear film contact line. These observations not only support emergent hypotheses concerning the formation of Marx\\'s line, a region of epithelial cell staining adjacent to the contact line on the eyelid, but also enhance our understanding of the pathophysiological consequences of the flow profile near the tear film contact line. © 2013 Society for Mathematical Biology.

  13. Analysis of meniscal degeneration and meniscal gene expression

    Directory of Open Access Journals (Sweden)

    Norton James H

    2010-01-01

    Full Text Available Abstract Background Menisci play a vital role in load transmission, shock absorption and joint stability. There is increasing evidence suggesting that OA menisci may not merely be bystanders in the disease process of OA. This study sought: 1 to determine the prevalence of meniscal degeneration in OA patients, and 2 to examine gene expression in OA meniscal cells compared to normal meniscal cells. Methods Studies were approved by our human subjects Institutional Review Board. Menisci and articular cartilage were collected during joint replacement surgery for OA patients and lower limb amputation surgery for osteosarcoma patients (normal control specimens, and graded. Meniscal cells were prepared from these meniscal tissues and expanded in monolayer culture. Differential gene expression in OA meniscal cells and normal meniscal cells was examined using Affymetrix microarray and real time RT-PCR. Results The grades of meniscal degeneration correlated with the grades of articular cartilage degeneration (r = 0.672; P HLA-DPA1, integrin, beta 2 (ITGB2, ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1, ankylosis, progressive homolog (ANKH and fibroblast growth factor 7 (FGF7, were expressed at significantly higher levels in OA meniscal cells compared to normal meniscal cells. Importantly, many of the genes that have been shown to be differentially expressed in other OA cell types/tissues, including ADAM metallopeptidase with thrombospondin type 1 motif 5 (ADAMTS5 and prostaglandin E synthase (PTGES, were found to be expressed at significantly higher levels in OA meniscal cells. This consistency suggests that many of the genes detected in our study are disease-specific. Conclusion Our findings suggest that OA is a whole joint disease. Meniscal cells may play an active role in the development of OA. Investigation of the gene expression profiles of OA meniscal cells may reveal new therapeutic targets for OA therapy and also may uncover novel

  14. Meniscal Tear Film Fluid Dynamics Near Marx’s Line

    KAUST Repository

    Zubkov, V. S.; Breward, C. J. W.; Gaffney, E. A.

    2013-01-01

    meniscus. However, resolving tear film behaviour within the meniscus and especially its apices is required to characterise the flow dynamics where the tear film is especially thin, and thus most susceptible to evaporatively induced hyperosmolarity

  15. Bucket elevator linkage for coarse coal washer

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, R.

    1985-09-03

    A continuous bucket elevator used in a method of separating coal according to its size and for cleaning refuse material from the coal in a Baum-type jigging apparatus wherein each bucket is connected to the adjacent bucket by a link received by a roll pin held by a bushing at each end in each bucket and the flange of a plate which is centrally welded to the bucket and has portions biased outwardly therefrom which merge into further portions having openings for receiving the roll pins, the diameter of the aligned openings in the further part, in the bushings, and in intervening link and the diameter of the roll pins being such so as to restrict wear due to the abrasive nature of the material being handled so that all components of the elevator wear out at about the same time and need not be replaced until after two or three cycles of use, each cycle being normally for seven and ten months.

  16. MRI as an accurate tool for the diagnosis and characterization of different knee joint meniscal injuries

    Directory of Open Access Journals (Sweden)

    Ayman F. Ahmed

    2017-12-01

    Conclusion: MRI of the knee will give the orthopedic surgeons ability to select suitable treatment and arthroscopic interference for their patients. MRI has high accuracy in meniscal tears diagnosis allowing accurate grading of them.

  17. Magnetic resonance imaging of meniscal and anterior cruciate ligament injuries of the knee

    International Nuclear Information System (INIS)

    Kreitner, K.F.; Herrig, A.; Grebe, P.; Runkel, M.; Regentrop, H.J.

    1998-01-01

    To categorise discrepancies in findings of the menisci and anterior cruciate ligament (ACL) between arthroscopy and MRI. Materials and methods: The MRIs of 236 patients were retrospectively analysed by an experienced radiologist without knowledge of clinical and/for operative findings. Discrepancies in arthroscopic findings were reevaluated together with the arthroscopist to determine their cause of error. Results: The diagnostic accuracies for injuries of the medial and lateral meniscus and the ACL were 92.4%, 92.4%, and 94.1%. respectively. For the menisci, causes for discrepancies in findings (n=31) were: overinterpretation of central signal intensities with contact to the meniscal surface but without disturbance of the meniscal contour as a tear (n=12), insufficient arthroscopie evaluation of the knee joint (n=11), overlooked tears on MR imaging (n=6), misinterpretation of normal anatomic structures (n=1), ''magic angle'' phenomenon (n=1), and missed tears at MRI (n=1). Causes for discrepancies for the ACL (n=18) were: nearly complete versus complete rupture either at MRI or arthroscopy and vice versa (n=9), insufficient arthroscopic evaluation (n=6), insufficient MRI technique (n=2), and overlooked tear on MR imaging (n=1). Conclusions: Discrepant findings between MRI and arthroscopy may be also due to an insufficient arthroscopic evaluation in clinical routine. The close cooperation between surgeons and radiologists improves the understanding of the methods of each other. (orig.) [de

  18. Clinical Results of Arthroscopic Repair of Isolated Longitudinal Tear of Medial Meniscus by Vertical Cruciate Double Mattress Sutures with Outside-in Technique

    Directory of Open Access Journals (Sweden)

    Seyied Hamid Barzgar

    2013-09-01

    Full Text Available Introduction : Meniscal tears are one of the most common injuries treated by arthroscopic techniques. Arthroscopic meniscal repair is an accepted way of treatment for meniscal tears. Different arthroscopic techniques for meniscal repair are: inside-out, outside-in and all inside. In the first 2 techniques, meniscus is repaired by sutures and in the later by suture or by commercial ready implants . The goal of current study is assessing clinical results of arthroscopic repair of longitudinal meniscal tears with vertical cruciate double mattress sutures by outside-in technique after 9 months.   Methods: In this case series study, in 13 patients having criteria for engaging the study with longitudinal isolated meniscus tear, arthroscopic meniscal repair was done with vertical cruciate double mattress sutures by outside-in technique and patients were followed for 9 months.   Results: Of 13 patients, there were 12 males (92.3% and one female (7.7% aged 15-38 (average 28.3 years. In follow up period, there was one case (7.7% of irritation by subcutaneous knot. There was not any failure of repair. Average Lysholm score increased from 55.23 to 91.23 after 9 months of follow up, which was statistically significant (p<0.001. At the end of follow up period, there was not any medial joint line tenderness of knee, giving way or significant effusion or pain.   Conclusion: This study shows that this technique has a good short term outcome with no failure and low complications but it is necessary to do more long term studies to prove it.

  19. Prevalence of Discoid Meniscus During Arthroscopy for Isolated Lateral Meniscal Pathology in the Pediatric Population.

    Science.gov (United States)

    Ellis, Henry B; Wise, Kelsey; LaMont, Lauren; Copley, Lawson; Wilson, Philip

    2017-06-01

    Meniscus tears in the young patient are becoming more prevalent. Knowledge of presenting characteristics and morphology can affect treatment decisions. The purpose of this study was to review and evaluate all the isolated lateral meniscus pathology that required arthroscopic treatment in a pediatric sports medicine practice and compare presenting characteristics between those with a discoid meniscus and those with normal meniscal morphology. We performed a retrospective review of all isolated lateral meniscus arthroscopic procedures from 2003 to 2012 in a high-volume pediatric sports practice. Presentation, radiographs, and intraoperative findings were reviewed. The prevalence and clinical findings of a discoid meniscus in this population and among all age groups were compared with those with a meniscus tear occurring in a normal meniscus. Two hundred and sixty-one arthroscopies were performed for symptomatic isolated lateral menisci pathology. Of these, 75% were discoid in nature; the remainder was tears occurring in normal menisci. Ninety-six of 99 patients (97%) with lateral meniscus pathology under the age of 13 had a discoid meniscus and 66% presented with no injury. There was a transition within the population at 14 years of age, with a rise in the incidence of normal meniscal body tears. Even after this transition point, meniscal pathology incidence remained notable; 59% of isolated lateral meniscus pathology in patients between the ages of 14 and 16 years old were a discoid meniscus. Magnetic resonance imaging criteria for discoid meniscus (3 consecutive sagittal cuts or coronal mid-compartment measure) were unreliable after the age of 13 years old. The ratio of complete to incomplete discoids in all age groups was 4 to 3. In conclusion, discoid menisci have a high prevalence in isolated lateral meniscus pathology requiring knee arthroscopy. Clinical presentation, imaging, characteristics, and treatment may be different among different age groups. In the

  20. Three Tesla MRI for the diagnosis of meniscal and anterior cruciate ligament pathology: a comparison to arthroscopic findings

    International Nuclear Information System (INIS)

    Sampson, M.J.; Jackson, M.P.; Moran, C.J.; Moran, R.; Eustace, S.J.; Shine, S.

    2008-01-01

    Aim: To assess the accuracy of 3 T magnetic resonance imaging (MRI) in the evaluation of meniscal and anterior cruciate ligament (ACL) injury. Materials and methods: Sixty-one consecutive patients were identified who were referred for evaluation of suspected intra-articular pathology with a 3 T MRI and who, subsequently, underwent an arthroscopic procedure of the knee were included for the study. Two musculoskeletal radiologists interpreted the images. The sensitivity, specificity, positive predictive value, and negative predictive value were then calculated for the MRI versus the arthroscopic findings as a reference standard. Results: The sensitivity and specificity for the overall detection of meniscal tears in this study was 84 and 93%, respectively. The results for the medial meniscus separately were 91 and 93% and for the lateral 77 and 93%. The evaluation of ACL integrity was 100% sensitive and specific. The meniscal tear type was correctly identified in 75% of cases and its location in 94%. Conclusion: This study demonstrates good results of 3 T MRI in the evaluation of the injured knee. Caution should still be given to the interpretation on MRI of a lateral meniscus tear, and it is suggested that the standard diagnostic criteria of high signal reaching the articular surface on two consecutive image sections be adhered to even at these higher field strengths

  1. Posterior meniscus root tears: associated pathologies to assist as diagnostic tools.

    Science.gov (United States)

    Matheny, Lauren M; Ockuly, Andrew C; Steadman, J Richard; LaPrade, Robert F

    2015-10-01

    The purpose of this study was to investigate associated pathologies identified at arthroscopy in patients with meniscus root tears. This study was Institutional Review Board approved. All patients who underwent arthroscopic knee surgery where a complete meniscus root tear was identified were included in this study. Concurrent ligament tears and articular cartilage changes ≥Outerbridge grade 2 were recorded and stored in a data registry. Fifty patients (28 males, 22 females) [mean age = 36.5 years (range 17.1-68.1 years)] who were diagnosed with a medial or lateral meniscus root tear at arthroscopy were included in this study out of 673 arthroscopic surgeries (prevalence 7.4 %). Twenty-three (46 %) patients had a medial meniscus root tear, 26 (52 %) patients had a lateral meniscus root tear and one (2 %) patient had both. Thirty-four per cent of patients (n = 17) underwent partial meniscectomy, while 60 % (n = 31) underwent suture repair. During arthroscopy, 60 % (n = 30) of patients were diagnosed with an anterior cruciate ligament (ACL) tear. Patients with lateral meniscus root tears were 10.3 times (95 % CI 2.6-42.5) more likely to have ACL tears than patients with medial meniscus root tears (p = 0.012). Patients who had medial meniscus root tears were 5.8 times (95 % CI 1.6-20.5) more likely to have chondral defects than patients who had lateral meniscus root tears (p = 0.044). In this study, patients' preoperative functional scores and activity levels were low. Patients with lateral meniscal root tears were more likely to have an ACL tear. Patients with medial meniscal root tears were more likely to have an knee articular cartilage defect with an Outerbridge grade 2 or higher chondral defect. This study confirms the importance of comprehensive assessment of concurrent injuries to properly diagnose meniscus root tears. IV.

  2. Single-leaf partial meniscectomy in extensive horizontal tears of the discoid lateral meniscus: Does decreased peripheral meniscal thickness affect outcomes? (Mean four-year follow-up).

    Science.gov (United States)

    Lee, Se-Won; Chun, Yong-Min; Choi, Chong-Hyuk; Kim, Sung-Jae; Jung, Min; Han, Joon-Woo; Kim, Sung-Hwan

    2016-06-01

    To evaluate whether single-leaf partial meniscectomy in horizontal tears along the entire discoid lateral meniscus has any advantages in clinical and radiological results compared with other meniscectomies in discoid lateral meniscus. A total of 145 patients with a horizontal tear pattern in symptomatic lateral discoid meniscus were retrospectively reviewed. Twenty-seven patients had undergone full-extent single-leaf partial meniscectomy (group A), 60 had undergone conventional partial meniscectomy (saucerization) maintaining peripheral meniscal height (group B), and 58 patients had undergone total meniscectomy (group C). Each patient was evaluated with the Lysholm knee score, International Knee Documentation Committee (IKDC) subjective grading, and modified Kellgren-Lawrence grade in plain radiography at their last follow-up. Group C had inferior functional results to groups A and B on the Lysholm knee score and IKDC subjective score. There was no significant difference between groups A and B. Group C fared significantly worse than groups A and B (p=0.003, pmeniscus tears, the full-extent single-leaf partial meniscectomy group had no adverse results compared with the total meniscectomy group and was not significantly different compared to the conventional partial meniscectomy group. Cohort study. Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Reliability and Validity of the IKDC, KOOS, and WOMAC for Patients With Meniscal Injuries.

    Science.gov (United States)

    van de Graaf, Victor A; Wolterbeek, Nienke; Scholtes, Vanessa A B; Mutsaerts, Eduard L A R; Poolman, Rudolf W

    2014-06-01

    Several patient-reported outcome measurements are used to measure functional outcome after treatment of meniscal injuries. However, for comparison of study results, there is a need for a uniform and standardized approach of measuring functional outcome. Selection of the instrument should be based on the quality of its measurement properties, and only the best instrument can be justified to be used. This study aimed to determine and compare the measurement properties of the Dutch-language versions of the International Knee Documentation Committee (IKDC) Subjective Knee Form, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) in a homogeneous group of patients with meniscal tears. Cohort study (design); Level of evidence, 2. Patients on the waiting list for meniscal surgery and patients between 6 weeks and 6 months after meniscal surgery were included (n = 75). Patients were excluded if they received an arthroplasty or had surgery on the anterior cruciate ligament. Internal consistency (Cronbach alpha), test-retest reliability (intraclass correlation coefficient [ICC]), measurement error (SEM), smallest detectable difference (SDD), content validity, construct validity (factor analysis and hypothesis testing), and floor and ceiling effects were determined. Results for the IKDC, KOOS dimensions, and WOMAC dimensions, respectively, were as follows: Cronbach alpha = .90, .72-.95, and .84-.95; ICC = 0.93, 0.84-0.89, and 0.77-0.89; SEM = 5.3, 7.0-12.6, and 7.3-12.2; SDD = 14.6, 19.4-35.0, and 20.2-33.9; hypotheses testing confirmation = 100%, 86%, and 85%. Floor effects within the SDD from the minimum score were found for the KOOS Sports/Recreation and Quality of Life dimensions. Ceiling effects within the SDD from the maximum score were found for the KOOS Activities of Daily Living and for all WOMAC dimensions. The IKDC showed the best performance on all measurement properties, implying that the IKDC

  4. Evaluation of Meniscal Mechanics and Proteoglycan Content in a Modified Anterior Cruciate Ligament Transection Model

    Science.gov (United States)

    Fischenich, Kristine M.; Coatney, Garrett A.; Haverkamp, John H.; Button, Keith D.; DeCamp, Charlie; Haut, Roger C.; Haut Donahue, Tammy L.

    2014-01-01

    Post-traumatic osteoarthritis (PTOA) develops as a result of traumatic loading that causes tears of the soft tissues in the knee. A modified transection model, where the anterior cruciate ligament (ACL) and both menisci were transected, was used on skeletally mature Flemish Giant rabbits. Gross morphological assessments, elastic moduli, and glycosaminoglycan (GAG) coverage of the menisci were determined to quantify the amount of tissue damage 12 weeks post injury. This study is one of the first to monitor meniscal changes after inducing combined meniscal and ACL transections. A decrease in elastic moduli as well as a decrease in GAG coverage was seen. PMID:24749144

  5. Arthroscopic Treatment of Discoid Lateral Meniscus Tears in Children With Achondroplasia.

    Science.gov (United States)

    Atanda, Alfred; Wallace, Maegen; Bober, Michael B; Mackenzie, William

    2016-01-01

    Achondroplasia is the most common form of skeletal dysplasia that presents to the pediatric orthopaedist. More than half of achondroplasia patients are affected with knee pain. It is thought that the majority of this pain may be due to spinal stenosis, hip pathology, or knee malalignment. Discoid menisci can be a source of lateral knee joint pain in skeletally immature patients in general. We present the first case series of patients with achondroplasia who had symptomatic discoid lateral menisci treated with arthroscopic knee surgery. The charts of 6 patients (8 knees) with achondroplasia who underwent arthroscopic knee surgery for symptomatic discoid lateral menisci were collected. History and physical examination data, magnetic resonance imaging findings, and operative reports were reviewed. Meniscal tear configuration and treatment type (meniscectomy vs. repair) were noted. Each patient was found to have a tear of the discoid meniscus. All menisci were treated with saucerization. In addition, meniscal repair was performed in 2 cases, partial meniscectomy in 3 cases, and subtotal meniscectomy in 3 cases. Two patients had bilateral discoid meniscal tears which were treated. Average follow-up was 2.4 years (range, 1 to 4.5 y) and the average pediatric International Knee Documentation Committee (pedi-IKDC) score was 85.3% (range, 75% to 95.4%). At final follow-up, all patients were pain free and able to return to full activities. Discoid meniscus tears may be a source of lateral joint line pain in patients with achondroplasia. These injuries can be successfully treated with arthroscopic surgery in this patient population. Future studies need to be done to determine the exact incidence of discoid menisci in achondroplasia patients and also to determine whether there is a genetic relationship between the 2 conditions. Level IV-case series.

  6. Bucket wheel excavator performances at Neyveli lignite mine

    Energy Technology Data Exchange (ETDEWEB)

    Kumaraswamy, S; Mozumdar, B K

    1987-03-01

    Bucket-wheel excavators have been in use at the Neyveli Lignite Mine in the State of Tamil Nadu, India, since the early nineteen-sixties. The mining environment has been particularly harsh for BWE application. The adverse influencing factors are the hardness of the over-burden formation, high abrasivity of rock and artesian ground water conditions. In this paper, the performances of the BWEs at Neyveli have been statistically analysed to determine the effects of physico-mechanical properties of overburden, blasting and rainfall on machine productivity, availability, wear-and-tear of bucket teeth, power consumption, production efficiency and cost of mining. An empirical relationship between the production efficiency, defined as the ratio of actual production rate to the theoretical one, and the bench height and width, height of slices, specific cutting resistance of the overburden material and its clay content, consumption of explosives, and conveyor length has been established.

  7. UTE-T2* mapping detects sub-clinical meniscus injury after anterior cruciate ligament tear

    Science.gov (United States)

    Williams, A.; Qian, Y.; Golla, S.; Chu, C.R.

    2018-01-01

    SUMMARY Objective Meniscus tear is a known risk factor for osteoarthritis (OA). Quantitative assessment of meniscus degeneration, prior to surface break-down, is important to identification of early disease potentially amenable to therapeutic interventions. This work examines the diagnostic potential of ultrashort echo time-enhanced T2* (UTE-T2*) mapping to detect human meniscus degeneration in vitro and in vivo in subjects at risk of developing OA. Design UTE-T2* maps of 16 human cadaver menisci were compared to histological evaluations of meniscal structural integrity and clinical magnetic resonance imaging (MRI) assessment by a musculoskeletal radiologist. In vivo UTE-T2* maps were compared in 10 asymptomatic subjects and 25 ACL-injured patients with and without concomitant meniscal tear. Results In vitro, UTE-T2* values tended to be lower in histologically and clinically normal meniscus tissue and higher in torn or degenerate tissue. UTE-T2* map heterogeneity reflected collagen disorganization. In vivo, asymptomatic meniscus UTE-T2* values were repeatable within 9% (root-mean-square average coefficient of variation). Posteromedial meniscus UTE-T2* values in ACL-injured subjects with clinically diagnosed medial meniscus tear (n = 10) were 87% higher than asymptomatics (n = 10, P meniscus degeneration. Further study is needed to determine whether elevated subsurface meniscus UTE-T2* values predict progression of meniscal degeneration and development of OA. PMID:22306000

  8. MR imaging of the combined anterior and posterior cruciate ligament tears: focussing on the ratterns of injuries and associated findings

    International Nuclear Information System (INIS)

    Kwon, Seon Young; Choi, Chang Lak; Park, Dal Soo; Park, Eun Hee; Lee, Sang Ho; Song, Mun Kab; Lee, Kwang Won; Kwon, Soon Tae

    1997-01-01

    To evaluate the patterns of injuries and frequency of associated findings on MR imaging in patients with both anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL)tears;to compare the associated findings, as seen on MR imaging, in cases with both ACL and PCL tears with those with ACL or PCL tears. Ten patients with compbined ACL and PCL tears, 16 with ACL tears and 18 with PCL tears, all confirmed by arthroscopy or open surgery, were involved in this study. To identify the associated knee injuries, MR images were retrospectively evaluated. In ten patients with combined ACL and PCL tears, open surgery led to the identification of six complete ACL tears (60%), four partial ACL tears (40%), eitht complete PCL tears (80%) and two partial PCL tears (20%). Injuries associated with these combined tears, and revealed by MR imaging, comprised six medial collateral ligament injuries (60%), six lateral collateral ligament jnjuries (60%), five medial meniscal injuries (50%), three lateral meniscal injuries (30%), nine bony injuries (90%), two posterior capsular injuries (20%), and three popliteus muscle injuries (30%). The frequency of popliteus muscle injury was significantly different (p<0.05, Fisher's exact test) between the group with both ACL and PCL tears and that with ACL or PCL tears. Associated findings in patients with combined ACL and PCL tears are more frequent than in those with ACL or PCL tears. In cases involving combined ACL and PCL tears, associated findings-as seen on MR images-should thus be carefully examined

  9. Familial Discoid Medial Meniscus Tear in Three Members of a Family: A Case Report and Review of Literature

    OpenAIRE

    Ahmed Ali, Raheel; McKay, Scott

    2014-01-01

    Background. A discoid meniscus is a thickened variant of the normal C-shaped meniscus prone to injury. Discoid medial meniscal tears have rarely been reported within families and may suggest familial or developmental origins. Methods. We report the cases of two Caucasian brothers with symptomatic discoid medial meniscus tears. A literature review was conducted addressing discoid medial meniscus and cases of familial meniscus tears. Case Presentation. Physically active brothers presented with ...

  10. Meniscus transplantation in skeletally immature patients.

    Science.gov (United States)

    Kocher, Mininder S; Tepolt, Frances A; Vavken, Patrick

    2016-07-01

    Meniscal pathology in skeletally immature patients includes meniscal tears and discoid lateral meniscus. Total or subtotal meniscectomy may occur in patients with discoid lateral meniscus or severe meniscal tears. Meniscal transplantation may be an option in skeletally immature patients status after total or subtotal meniscectomy with knee symptoms or dysfunction. This study focuses on the surgical technique and short-term outcomes of meniscus transplantation in skeletally immature patients. We reviewed our clinical database for skeletally immature patients who had undergone meniscus transplantation with a minimum of 2 years of follow-up. Patients were contacted, invited for a physical exam, and asked to complete a Pedi-IKDC, Lysholm, and Tegner outcomes questionnaire. The study protocol was approved by the responsible institutional review board. Three patients (two females/one male) were eligible for the study, each of whom responded to our invitation indicating availability for physical exam and questionnaire. Two patients had undergone subtotal discoid meniscus resection, leading to early lateral compartment degeneration. One patient developed advanced degeneration after a delay in treatment for a medial bucket-handle tear associated with anterior cruciate ligament rupture. The mean age of the patients at the time of surgery was 12.6±2.3 years. At a mean follow-up of 31±20 months, the mean Pedi-IKDC score was 68.3±4, the mean Lysholm was 55.7±22.3, and the median Tegner was 7 points. There were no indications of growth deformity during the regular postoperative radiological assessments. One patient required subsequent lysis of adhesions along the lateral mini arthrotomy and mobilization under anesthesia. The other two patients were able to return to sports at the same level as before meniscus transplantation and were able to do so within 9 months postoperatively. Over-resection of discoid menisci as well as untreated meniscus injury, the latter typically in

  11. A Cohort Study on Meniscal Lesions among Airport Baggage Handlers

    DEFF Research Database (Denmark)

    Mikkelsen, Sigurd; Brauer, Charlotte; Pedersen, Ellen Bøtker

    2016-01-01

    and then decreased slowly to reach unity after approximately 30 years, adjusted for effects of potential confounders. This relation between baggage handling and meniscal lesions was present for work on the apron which involves lifting in a kneeling or squatting position, but not in the baggage hall, which only...

  12. Potential Market for New Meniscus Repair Strategies: Evaluation of the MOON Cohort

    Science.gov (United States)

    Fetzer, Gary B.; Spindler, Kurt P.; Amendola, Annunziato; Andrish, Jack T.; Bergfeld, John A.; Dunn, Warren R.; Flanigan, David C.; Jones, Morgan; Kaeding, Christopher C.; Marx, Robert G.; Matava, Matthew J.; McCarty, Eric C.; Parker, Richard D.; Wolcott, Michelle; Vidal, Armando; Wolf, Brian R.; Wright, Rick W.

    2013-01-01

    Background An estimated 200,000 ACL reconstructions are performed each year in the United States. The presence of concomitant meniscus tears and subsequent treatment at the time of ACL reconstruction may determine long-term outcomes of these knees. The authors contend that a substantial number of these meniscal tears are treated in a fashion that reduces meniscal function and that new technologies are needed to treat meniscal tears in a fashion that preserves function. A large cohort of patients with meniscal tears is needed to demonstrate this need. The purpose of this study is to determine the incidence of meniscal tears, describe tear morphology, and selected treatment in the MOON prospective longitudinal cohort of ACL reconstruction. We also will demonstrate based on national statistics the large potential market that exists for future tissue engineering aimed at preserving meniscal function. Methods A multicenter cohort of 1014 patients undergoing ACL reconstruction between January 2002 and December 2003 were evaluated. All procedures were performed by nine fellowship trained sports medicine orthopaedic surgeons. Data on patient demographics, presence of a meniscus tear at time of ACL reconstruction, tear morphology, and meniscal treatment were collected prospectively. Meniscal tears were categorized into three potential tissue engineering treatment strategies: all-biologic repair, advanced repair, and scaffold replacement. Results 1014 ACL reconstructions were performed over the two year period. The median age at the time of surgery was 24 years. Thirty-six percent of the knees had medial meniscal tears and 44% of the knees had lateral meniscal tears. Longitudinal tears were the most common tear morphology. The most frequent treatment modality was partial meniscectomy (60%). Thirty percent of medial meniscal tears and 10% of lateral meniscal tears could be treated with all-biologic repair, 32% of medial meniscal tears and 28% of lateral meniscal tears could

  13. Arthroscopic all-inside meniscal repair - Does the meniscus heal? A clinical and radiological follow-up examination to verify meniscal healing using a 3-T MRI

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    Hoffelner, Thomas; Resch, Herbert; Mayer, Michael; Tauber, Mark [Department of Traumatology and Sports Injuries, Salzburg (Austria); Forstner, Rosemarie [University Hospital of Salzburg, Department of Radiology, Salzburg (Austria); Minnich, Bernd [University of Salzburg, Department of Organismic Biology, Salzburg (Austria)

    2011-02-15

    The purpose of this study was to correlate clinical and radiological results using a 3-T MRI to verify meniscal healing after arthroscopic all-inside meniscus repair. We selected 27 patients (14 men and 13 women) with an average age of 31 {+-} 9 years and retrospective clinical examinations and radiological assessments using a 3-T MRI after all-inside arthroscopic meniscal repair were conducted. Repair of the medial meniscus was performed in 19 patients and of the lateral meniscus in eight. In 17 patients (63%), we performed concomitant anterior cruciate ligament reconstruction. The mean follow-up period was 4.5 {+-} 1.7 years. The Lysholm score and Tegner activity index were used for clinical evaluation. Four grades were used to classify the radiological signal alterations within the meniscus: central globular (grade 1); linear horizontal or band-like (grade 2); intrameniscal alterations and linear signal alterations communicating with the articular surface (grade 3); and complex tears (grade 4). At follow-up, the average Lysholm score was 76 {+-} 15 points, with ten of the patients placed in group 6 based on the Tegner activity index. MRI examinations revealed no signal alteration in three patients, grade 1 in 0, grade 2 in five, grade 3 in 13, and grade 4 in six. The MRI findings correlated positively with the clinical scores in 21 patients (78%). Correlation of clinical and radiological examination was performed using 3-T MRI. In spite of satisfactory clinical outcomes at follow-up, a radiological signal alteration may still be visible on MRI, which was believed to be scar tissue, but could not be proven definitively. Imaging with a 3-Tesla MRI after meniscal suture surgery provides good but no definitive reliability on meniscus healing and therefore gives no advantage compared to 1.5-T MRI, with good clinical outcome using an all-inside arthroscopic meniscal repair. 3T-MRI can not substitute diagnostic arthroscopy in patients with persistent complaints after

  14. Arthroscopic all-inside meniscal repair - Does the meniscus heal? A clinical and radiological follow-up examination to verify meniscal healing using a 3-T MRI

    International Nuclear Information System (INIS)

    Hoffelner, Thomas; Resch, Herbert; Mayer, Michael; Tauber, Mark; Forstner, Rosemarie; Minnich, Bernd

    2011-01-01

    The purpose of this study was to correlate clinical and radiological results using a 3-T MRI to verify meniscal healing after arthroscopic all-inside meniscus repair. We selected 27 patients (14 men and 13 women) with an average age of 31 ± 9 years and retrospective clinical examinations and radiological assessments using a 3-T MRI after all-inside arthroscopic meniscal repair were conducted. Repair of the medial meniscus was performed in 19 patients and of the lateral meniscus in eight. In 17 patients (63%), we performed concomitant anterior cruciate ligament reconstruction. The mean follow-up period was 4.5 ± 1.7 years. The Lysholm score and Tegner activity index were used for clinical evaluation. Four grades were used to classify the radiological signal alterations within the meniscus: central globular (grade 1); linear horizontal or band-like (grade 2); intrameniscal alterations and linear signal alterations communicating with the articular surface (grade 3); and complex tears (grade 4). At follow-up, the average Lysholm score was 76 ± 15 points, with ten of the patients placed in group 6 based on the Tegner activity index. MRI examinations revealed no signal alteration in three patients, grade 1 in 0, grade 2 in five, grade 3 in 13, and grade 4 in six. The MRI findings correlated positively with the clinical scores in 21 patients (78%). Correlation of clinical and radiological examination was performed using 3-T MRI. In spite of satisfactory clinical outcomes at follow-up, a radiological signal alteration may still be visible on MRI, which was believed to be scar tissue, but could not be proven definitively. Imaging with a 3-Tesla MRI after meniscal suture surgery provides good but no definitive reliability on meniscus healing and therefore gives no advantage compared to 1.5-T MRI, with good clinical outcome using an all-inside arthroscopic meniscal repair. 3T-MRI can not substitute diagnostic arthroscopy in patients with persistent complaints after

  15. KNEE PROPRIOCEPTION FOLLOWING MENISCAL REPAIR

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    Brytsko A. A.

    2018-02-01

    Full Text Available Background. It is well known that meniscectomy leads to osteoarthritis of the knee and proprioception impairment. Objective. The aim of this study was to assess retrospectively the joint position sense after meniscal suture and partial medial meniscal resection and to estimate the patients’ satisfaction with knee function. Material and Methods. We evaluated the outcomes of 27 patients after meniscal repair and compared them to those of 24 patients after partial meniscal resection. We estimated the joint position sense at 30°, 45° and 60° of flexion using the Biodex system 4 Pro. All patients were assessed with the IKDC 2000 subjective knee score. Results. A statistically significant worsening in reproducing the injured joint position in comparison to the healthy limb in both groups was observed. These impairments were mostly expressed at 45° and 60° of knee flexion, and were worsening over time in the group of patients who had undergone medial meniscal resection. An average value by the IKDC 2000 scale after 24 months in the meniscorrhaphy group was 76.73 ± 11.17% and 68.93 ± 14.76% after partial medial meniscal resection. Сonclusion. The control over position of the knee is not impaired after meniscal repair. An overall satisfaction with joint function is higher in patients who undergo meniscal suture in comparison to the partial medial meniscal resection group.

  16. Diagnostic Validity of Combining History Elements and Physical Examination Tests for Traumatic and Degenerative Symptomatic Meniscal Tears.

    Science.gov (United States)

    Décary, Simon; Fallaha, Michel; Frémont, Pierre; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Feldman, Debbie E; Sylvestre, Marie-Pierre; Vendittoli, Pascal-André; Desmeules, François

    2017-10-27

    The current approach to the clinical diagnosis of traumatic and degenerative symptomatic meniscal tears (SMTs) proposes combining history elements and physical examination tests without systematic prescription of imaging investigations, yet the evidence to support this diagnostic approach is scarce. To assess the validity of diagnostic clusters combining history elements and physical examination tests to diagnose or exclude traumatic and degenerative SMT compared with other knee disorders. Prospective diagnostic accuracy study. Patients were recruited from 2 orthopedic clinics, 2 family medicine clinics, and from a university community. A total of 279 consecutive patients who underwent consultation for a new knee complaint. Each patient was assessed independently by 2 evaluators. History elements and standardized physical examination tests performed by a physiotherapist were compared with the reference standard: an expert physicians' composite diagnosis including a clinical examination and confirmatory magnetic resonance imaging. Participating expert physicians were orthopedic surgeons (n = 3) or sport medicine physicians (n = 2). Penalized logistic regression (least absolute shrinkage and selection operator) was used to identify history elements and physical examination tests associated with the diagnosis of SMT and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures were calculated including sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios (LR+/-) with associated 95% confidence intervals (CIs). Eighty patients had a diagnosis of SMT (28.7%), including 35 traumatic tears and 45 degenerative tears. The combination a history of trauma during a pivot, medial knee pain location, and a positive medial joint line tenderness test was able to diagnose (LR+ = 8.9; 95% CI 6.1-13.1) or exclude (LR- = 0.10; 95% CI 0.03-0.28) a traumatic SMT. Combining a history of

  17. Radiological classification of meniscocapsular tears of the anterolateral portion of the lateral meniscus of the knee

    International Nuclear Information System (INIS)

    George, J.; Packya, N.; Tan, A.H.; Paul, G.

    2000-01-01

    In an arthroscopic-MRI correlation study of acute injuries to the knee it was found that anterolateral meniscocapsular separations of the lateral aspect of the knee were missed on MRI reporting. Eighty sports-related injuries of the knee were seen by experienced orthopaedic surgeons at the University of Malaya Medical Centre and at the National Sports Centre, Malaysia from January 1996 to July 1997. Fifty of the patients were suspected to have meniscal tears that were either lateral or medial on clinical examination and they were sent for MRI. Many of these patients were tertiary referrals. Magnetic resonance imaging examinations in 27 of the 50 patients were reported as not showing any intrasubstance or obvious meniscocapsular tears, but arthroscopy performed on them revealed anterolateral meniscocapsular tears of the lateral meniscus of varying degrees in nine of these patients. In retrospect the tears could be seen on MRI, and a pattern to the tears was noted and classified as follows. Type 0, normal; type 1, torn inferior or superior meniscocapsular attachment; type 2, both meniscofemoral and meniscotibial ligaments torn but with minimal separation of meniscus and capsule by fluid or synovitis; and type 3, marked separation of meniscus and capsule by fluid (> 3 mm). Ten patients who did not undergo arthroscopy for various personal and financial reasons underwent MRI which showed type 1 and type 2 tears, and were treated conservatively. These patients were all asymptomatic after 4-6 weeks with regard to clinical signs, suggesting a lateral meniscal tear. Magnetic resonance imaging therefore does reveal minor degrees of meniscocapsular tears anterolaterally when one understands the normal anatomy in this region. Copyright (1999) Blackwell Science Pty Ltd

  18. The use of MRI in the investigation of lateral meniscal tear post medial unicompartmental knee replacement

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    Sanil H. Ajwani, MBChB, BSc (Hons, MRCS

    2015-06-01

    Full Text Available The evaluation of lateral knee pain in patients with a medial unicompartmental knee replacement (UKR is complex. The native lateral compartment structures are prone to the same injuries as patients with normal knees. Historical reports of lateral meniscal injury post medial UKR have argued MRI evaluation is obsolete due to artefact caused by the prosthesis. We report a case of lateral meniscal injury in a patient two years after successful medial UKR. We identified the offending pathology via utilization of MRI scanners adopting metal artefact reduction sequences (MARS. The MARS MRI protocol helps clinicians accurately and non-invasively evaluate soft tissue structures in knees with metal prostheses. It also allows surgeons to accurately counsel patients and provides a higher degree of certainty in treating the pathology.

  19. Meniscal position on routine MR imaging of the knee

    International Nuclear Information System (INIS)

    Miller, T.T.; Staron, R.B.; Feldman, F.; Cepel, E.

    1997-01-01

    Objective. To determine the prevalence of meniscal protrusion (i.e. location of the outer edge of a meniscus beyond the tibial articular surface), and to determine its relationship with internal derangement, joint effusion, and degenerative arthropathy. Design and patients. Sagittal and coronal MR images of 111 abnormal and 46 normal knees were evaluated for the presence of meniscal protrusion. We set 25% as the minimum amount of displacement considered abnormal because this was the smallest amount of displacement we could confidently discern. Presence of meniscal tear, anterior cruciate ligament (ACL) injury, joint effusion, or osteophytosis was also recorded. Results and conclusion. Normal examinations demonstrated protrusion of the medial meniscus in 6.5% of sagittal images and 15% of coronal images, and of the lateral meniscus in 2% and 13%, respectively. Fisher's exact test demonstrated a statistically significant difference between the normal and abnormal groups for the medial meniscus on both sagittal (P 0.2). A protruding medial meniscus was associated with effusion and osteophytosis (P 0.1). Posterior protrusion of the lateral meniscus was only associated with ACL injury (P<0.0001); protruding anterior horns and bodies of lateral menisci were not associated with any of the four abnormalities. It is concluded that the medial meniscus may occasionally protrude more than 25% of its width, but protrusion is more often due to effusion and osteophytes. Protrusion of the posterior horn of the lateral meniscus is associated with ACL insufficiency, while protrusion of the body and anterior horn of the lateral meniscus is a normal variant. (orig.). With 4 figs

  20. Lesão meniscal por fadiga Meniscal injury due to fatigue

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    Gilberto Luis Camanho

    2009-01-01

    Full Text Available OBJETIVO: O intuito do presente estudo é de analisar um grupo de pacientes portadores de lesão meniscal decorrente da falência estrutural sem relação com trauma ou problemas degenerativos, optando por chamá-la de lesão meniscal por fadiga. MATERIAL E MÉTODO: Foram avaliados 140 pacientes com lesão meniscal sem causa aparente e, portanto, considerados portadores da lesão meniscal por fadiga. Dentre eles, 85 pacientes eram do sexo masculino e 55 do sexo feminino. O menisco medial foi o mais acometido (92% dos casos. RESULTADOS: Todas as lesões foram diagnosticadas através de exame clínico e ressonância magnética. Os pacientes foram submetidos a meniscectomia por via artroscópica e os resultados foram divididos em dois tipos: bons e maus. Foram encontrados 27% de maus resultados dos quais nove pacientes evoluíram para osteonecrose idiopática. CONCLUSÃO: Concluímos que as lesões por fadiga devem ser analisadas como lesões provocadas por falência, portanto uma patologia sindrômica que pode evoluir para uma osteonecrose idiopática..OBJECTIVE: The purpose of the present study was to review a group of patients with meniscal injuries resulting from structural failure unrelated to trauma or degenerative problems to which was given the name "meniscal injury due to fatigue". MATERIAL AND METHOD: Evaluations were made on 140 patients with meniscal injuries without any apparent cause, who were therefore considered to have meniscal injuries due to fatigue. Among these, 85 patients were male and 55 were female. The medial meniscus was the most affected site (92% of the cases. RESULTS: All these injuries were diagnosed by means of clinical examination and magnetic resonance imaging. The patients underwent meniscectomy by means of arthroscopy and the results were divided into two types: good and poor. Poor results were found in 27% of the cases, among which nine patients progressed to idiopathic osteonecrosis. CONCLUSION: We conclude that

  1. Fibrochondrogenic potential of synoviocytes from osteoarthritic and normal joints cultured as tensioned bioscaffolds for meniscal tissue engineering in dogs

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    Jennifer J. Warnock

    2014-09-01

    Full Text Available Meniscal tears are a common cause of stifle lameness in dogs. Use of autologous synoviocytes from the affected stifle is an attractive cell source for tissue engineering replacement fibrocartilage. However, the diseased state of these cells may impede in vitro fibrocartilage formation. Synoviocytes from 12 osteoarthritic (“oaTSB” and 6 normal joints (“nTSB” were cultured as tensioned bioscaffolds and compared for their ability to synthesize fibrocartilage sheets. Gene expression of collagens type I and II were higher and expression of interleukin-6 was lower in oaTSB versus nTSB. Compared with nTSB, oaTSB had more glycosaminoglycan and alpha smooth muscle staining and less collagen I and II staining on histologic analysis, whereas collagen and glycosaminoglycan quantities were similar. In conclusion, osteoarthritic joint—origin synoviocytes can produce extracellular matrix components of meniscal fibrocartilage at similar levels to normal joint—origin synoviocytes, which makes them a potential cell source for canine meniscal tissue engineering.

  2. Visibility of Anterolateral Ligament Tears in Anterior Cruciate Ligament-Deficient Knees With Standard 1.5-Tesla Magnetic Resonance Imaging.

    Science.gov (United States)

    Hartigan, David E; Carroll, Kevin W; Kosarek, Frank J; Piasecki, Dana P; Fleischli, James F; D'Alessandro, Donald F

    2016-10-01

    To attempt to visualize the ligament with standard 1.5-tesla magnetic resonance imaging (MRI) in the acute anterior cruciate ligament (ACL)-torn knee, and if it is visible, attempt to characterize it as torn or intact at its femoral, meniscal, and tibial attachment sites. This was a retrospective MRI study based on arthroscopic findings of a known ACL tear in 72 patients between the years 2006 and 2010. Patients all had hamstring ACL reconstructions, no concomitant lateral collateral ligament, or posterolateral corner injury based on imaging and physical examination, and had a preoperative 1.5-tesla MRI scan with standard sequences performed within 3 weeks of the injury. Two fellowship-trained musculoskeletal radiologists retrospectively reviewed the preoperative MRI for visualization of the anterolateral ligament (ALL) for concomitant tears. Inter- and intraobserver reliability was calculated. Learning effect was analyzed to determine if radiologists' agreement improved as reads progressed. Both radiologists were able to visualize the ALL in 100% of the scans. Overall, ALL tears were noted in 26% by radiologist 1 and in 62% by radiologist 2. The agreement between the ligament being torn or not had a kappa of 0.54 between radiologists. The agreements in torn or not torn between radiologists in the femoral, meniscal, and tibial sites were 0.14, 0.15, and 0.31. The intraobserver reliability by radiologist 1 for femoral, meniscal, and tibial tears was 0.04, 0.57, and 0.54 respectively. For radiologist 2, they were 0.75, 0.61, and 0.55. There was no learning effect noted. ALL tears are currently unable to be reliably identified as torn or intact on standard 1.5-tesla MRI sequences. Proper imaging sequences are of crucial importance to reliably follow these tears to determine their clinical significance. Level IV, therapeutic case series study. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  3. Quantifying meniscal kinematics in dogs.

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    Park, Brian H; Banks, Scott A; Pozzi, Antonio

    2017-11-06

    The dog has been used extensively as an experimental model to study meniscal treatments such as meniscectomy, meniscal repair, transplantation, and regeneration. However, there is very little information on meniscal kinematics in the dog. This study used MR imaging to quantify in vitro meniscal kinematics in loaded dog knees in four distinct poses: extension, flexion, internal, and external rotation. A new method was used to track the meniscal poses along the convex and posteriorly tilted tibial plateau. Meniscal displacements were large, displacing 13.5 and 13.7 mm posteriorly on average for the lateral and medial menisci during flexion (p = 0.90). The medial anterior horn and lateral posterior horns were the most mobile structures, showing average translations of 15.9 and 15.1 mm, respectively. Canine menisci are highly mobile and exhibit movements that correlate closely with the relative tibiofemoral positions. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  4. Meniscus tear surgery and meniscus replacement

    Science.gov (United States)

    Vaquero, Javier; Forriol, Francisco

    2016-01-01

    Summary Objective the menisci are easily injured and difficult to repair. The aim of this study was to analyze the current state of meniscal surgery aimed at preserving morphology and conserving the biomechanics of the knee to prevent joint degeneration. Methodology a search of the electronic medical literature database Medline was conducted, from http://www.ncbi.nlm.nih.gov/pubmed. The search was not limited by language. Candidate articles were identified by searching for those that included the keywords meniscus, surgery, suture, implant, allograft. The limits were included for clinical research and clinical trials. Basic research was not included. The studies selected were evaluated and classified in three different categories: basic science, reconstruction (suture and meniscectomy) and implants (scaffolds and allograft). Results the consequences of meniscectomy performed at a young age can lead to a joint cartilage degeneration twenty years later. There are few surgical options for the repair of meniscal injuries in order both to preserve the meniscus and to ensure the long term survival of the knee joint, meniscectomy, repair, suturing the tear, or reconstruction, when a meniscal allograft or synthetic substitute is used to replace the meniscus, but the biomechanical properties of the native meniscus are not reproduced entirely by the scaffolds that exist today. Conclusion therapies that successfully repair or replace the meniscus are therefore likely to prevent or delay osteoarthritis progression. PMID:27331034

  5. MRI evaluation of the posterior meniscus root tear

    International Nuclear Information System (INIS)

    Zhang Jianjun; Zheng Zhuozhao; Li Xuan

    2010-01-01

    Objective: To determine the value of MRI for diagnosing the posterior meniscus root tear. Methods: MR examinations of 30 patients with tear of the posterior meniscus root confirmed by knee arthroscopies were retrospectively reviewed. Of the 30 patients, 17 with posterior medial meniscus root tear (MMRT) and 13 with posterior lateral meniscus root tear (LMRT). The diagnostic sensitivity of' MRI for the posterior meniscus root tear was analyzed. Fisher's exact test was used to compare the detection rate of MRI for MMRT with that for LMRT. Results: All 17 cases with MMRT and 9 cases out of 13 with LMRT were correctly diagnosed by MRI and the diagnostic sensitivity of MRI for the posterior meniscus root tear was 86.7% (26/30). The main MR appearance of the posterior meniscus root tear was distortion of the meniscal root, with its low signal replaced by abnormal high signal. The detection rate of MRI for MMRT (17/17) was significantly greater than that for LMRT (9/13) (P=0.026). The prevalence of MMRT associated with meniscus extrusion (15/17) was significantly greater than that of LMRT (6/13) (P=0.020), but the prevalence of MMRT associated with anterior cruciate ligament (ACL) injury (5/17) was significantly lower than that of LMRT (11/13) (P=0.004). Conclusion: MRI is a relatively good method for detection of posterior meniscus root tears and associated injuries. (authors)

  6. A Novel Repair Method for Radial Tears of the Medial Meniscus: Biomechanical Comparison of Transtibial 2-Tunnel and Double Horizontal Mattress Suture Techniques Under Cyclic Loading.

    Science.gov (United States)

    Bhatia, Sanjeev; Civitarese, David M; Turnbull, Travis Lee; LaPrade, Christopher M; Nitri, Marco; Wijdicks, Coen A; LaPrade, Robert F

    2016-03-01

    Complete radial tears of the medial meniscus have been reported to be functionally similar to a total meniscectomy. At present, there is no consensus on an ideal technique for repair of radial midbody tears of the medial meniscus. Prior attempts at repair with double horizontal mattress suture techniques have led to a reportedly high rate of incomplete healing or healing in a nonanatomic (gapped) position, which compromises the ability of the meniscus to withstand hoop stresses. A newly proposed 2-tunnel radial meniscal repair method will result in decreased gapping and increased ultimate failure loads compared with the double horizontal mattress suture repair technique under cyclic loading. Controlled laboratory study. Ten matched pairs of male human cadaveric knees (average age, 58.6 years; range, 48-66 years) were used. A complete radial medial meniscal tear was made at the junction of the posterior one-third and middle third of the meniscus. One knee underwent a horizontal mattress inside-out repair, while the contralateral knee underwent a radial meniscal repair entailing the same technique with a concurrent novel 2-tunnel repair. Specimens were potted and mounted on a universal testing machine. Each specimen was cyclically loaded 1000 times with loads between 5 and 20 N before experiencing a load to failure. Gap distances at the tear site and failure load were measured. The 2-tunnel repairs exhibited a significantly stronger ultimate failure load (median, 196 N; range, 163-212 N) than did the double horizontal mattress suture repairs (median, 106 N; range, 63-229 N) (P = .004). In addition, the 2-tunnel repairs demonstrated decreased gapping at all testing states (P meniscus significantly decrease the ability of the meniscus to dissipate tibiofemoral loads, predisposing patients to early osteoarthritis. Improving the ability to repair medial meniscal radial tears in a way that withstands cyclic loads and heals in an anatomic position could significantly

  7. Development of a Micronized Meniscus Extracellular Matrix Scaffold for Potential Augmentation of Meniscal Repair and Regeneration.

    Science.gov (United States)

    Monibi, Farrah A; Bozynski, Chantelle C; Kuroki, Keiichi; Stoker, Aaron M; Pfeiffer, Ferris M; Sherman, Seth L; Cook, James L

    2016-12-01

    Decellularized scaffolds composed of extracellular matrix (ECM) hold promise for repair and regeneration of the meniscus, given the potential for ECM-based biomaterials to aid in stem cell recruitment, infiltration, and differentiation. The objectives of this study were to decellularize canine menisci to fabricate a micronized, ECM-derived scaffold and to determine the cytocompatibility and repair potential of the scaffold ex vivo. Menisci were decellularized with a combination of physical agitation and chemical treatments. For scaffold fabrication, decellularized menisci were cryoground into a powder and the size and morphology of the ECM particles were evaluated using scanning electron microscopy. Histologic and biochemical analyses of the scaffold confirmed effective decellularization with loss of proteoglycan from the tissue but no significant reduction in collagen content. When washed effectively, the decellularized scaffold was cytocompatible to meniscal fibrochondrocytes, synoviocytes, and whole meniscal tissue based on the resazurin reduction assay and histologic evaluation. In an ex vivo model for meniscal repair, radial tears were augmented with the scaffold delivered with platelet-rich plasma as a carrier, and compared to nonaugmented (standard-of-care) suture techniques. Histologically, there was no evidence of cellular migration or proliferation noted in any of the untreated or standard-of-care treatment groups after 40 days of culture. Conversely, cellular infiltration and proliferation were noted in scaffold-augmented repairs. These data suggest the potential for the scaffold to promote cellular survival, migration, and proliferation ex vivo. Further investigations are necessary to examine the potential for the scaffold to induce cellular differentiation and functional meniscal fibrochondrogenesis.

  8. A new arthroscopic classification of degenerative medial meniscus root tear that correlates with meniscus extrusion on magnetic resonance imaging.

    Science.gov (United States)

    Bin, Seong-Il; Jeong, Tae-Wan; Kim, Su-Jin; Lee, Dae-Hee

    2016-03-01

    To determine a new classification system for medial meniscus root tears (MMRT) based on arthroscopic findings. 24 knees (55%) belonged to the nondisplaced or overlapped group, and 20 knees (45%) to the widely displaced group. Absolute meniscal extrusion was defined as distance between outer edge of the articular cartilage of tibial plateau and meniscal outer edge. Relative extrusion was defined as extruded meniscus width divided by entire meniscal width, multiplied by 100. The proportion of knees with major (>3 mm) extrusion were compared in two groups, as were the severity of chondral wear and osteoarthritic change. Absolute (4.6 mm vs. 3.7 mm, P=0.006) and relative (46% vs. 39%, P=0.042) extrusion of the medial meniscus were greater in widely displaced than in nondisplaced or overlapped group. Medial joint space width was significantly narrower in the widely displaced than in the nondisplaced or overlapped group (3.0 mm vs. 4.0 mm, P=0.007). The widely displaced group had a 4° greater varus deformity, and higher rates of major extrusion (>3 mm), grade III or IV chondral wear in the medial femoral condyle (60% vs. 29%, P=0.039) and medial compartment osteoarthritis (75% vs. 21%, P=0.001) than did the nondisplaced or overlapped group. Widely displaced MMRT had greater meniscal extrusion and more severe chondral wear and osteoarthritis than did nondisplaced or overlapped MMRT. In this novel classification system, the stage of MMRT severity was associated with tear site displacement. Case series (level IV). Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Determination Of Longevity Of Teeth In Buckets Of Loading Equipment In Coal Mines - A Case Study

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    Aarif Jamal

    2015-08-01

    Full Text Available The life of bucket teeth in shovel and dragline deployed in handling of overburden rock is an important contributor to the stores cost and is also responsible for the loss of valuable availability and utilisation time of these critical equipment. To ascertain the effect of rock type on longevity of bucket teeth a study has been conducted in two large opencast mines of Singrauli Coalfields. The results of this study is presented in this paper. There was a significant variation as compared to the actual figures of the mine it establish useful relationship between the type of mineral present in the overburden and the life of bucket teeth of shovel and dragline.

  10. PERANCANGAN PROTOTIPE BUCKET ELEVATOR

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    Dani Irawan

    2017-08-01

    Full Text Available Alat Pemindah Bahan merupakan salah satu peralatan yang digunakan untuk kegiatan sehari-hari pada proses keberlangsungan produksi di masyarakat. Agar peralatan tersebut tetap dapat berfungsi dengan baik masyarakat, maka perlu adanya tindakan rancang bangun prototype Bucket konveyor ini guna untuk membatu masyarakat agar lebih memahami betapa pentingnya alat mekanis. Metode Perancangan Prototipe Bucket Konveyor meliputi: Perancangan Desain, Perancangan Elemen Mesin Perancangan Biaya (biaya produksi, biaya penjualan, break event point. Berdasarkan Rancang Bangun Prototipe Mesin Bucket Konveyor yang telah dilakukan, didapatkan hasil yaitu daya motor bucket 8,5 W dengan kapasitas 4 liter/s dan biaya pembuatan bukcet adalah Rp. 5.760.500,- biaya pembuatan ini meliputi biaya bahan baku, operasional, dan permesinan.

  11. The relation between chondromalacia patella and meniscal tear and the sulcus angle/ trochlear depth ratio as a powerful predictor.

    Science.gov (United States)

    Resorlu, Hatice; Zateri, Coskun; Nusran, Gurdal; Goksel, Ferdi; Aylanc, Nilufer

    2017-01-01

    To investigate the relation between chondromalacia patella and the sulcus angle/trochlear depth ratio as a marker of trochlear morphology. In addition, we also planned to show the relationship between meniscus damage, subcutaneous adipose tissue thickness as a marker of obesity, patellar tilt angle and chondromalacia patella. Patients with trauma, rheumatologic disease, a history of knee surgery and patellar variations such as patella alba and patella baja were excluded. Magnetic resonance images of the knees of 200 patients were evaluated. Trochlear morphology from standardized levels, patellar tilt angle, lateral/medial facet ratio, subcutaneous adipose tissue thickness from 3 locations and meniscus injury were assessed by two specialist radiologists. Retropatellar cartilage was normal in 108 patients (54%) at radiological evaluation, while chondromalacia patella was determined in 92 (46%) cases. Trochlear sulcus angle and prepatellar subcutaneous adipose tissue thickness were significantly high in patients with chondromalacia patella, while trochlear depth and lateral patellar tilt angle were low. The trochlear sulcus angle/trochlear depth ratio was also high in chondromalacia patella and was identified as an independent risk factor at regression analysis. Additionally, medial meniscal tear was observed in 35 patients (38%) in the chondromalacia patella group and in 27 patients (25%) in the normal group, the difference being statistically significant (P = 0.033). An increased trochlear sulcus angle/trochlear depth ratio is a significant predictor of chondromalacia patella. Medial meniscus injury is more prevalent in patients with chondromalacia patella in association with impairment in knee biomechanics and the degenerative process.

  12. MRI diagnosis of ACL bundle tears: value of oblique axial imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Alex W.H.; Griffith, James F.; Hung, Esther H.Y. [Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince of Wales Hospital, Shatin, NT, Hong Kong SAR (China); Law, Kan Yip; Yung, Patrick S.H. [Chinese University of Hong Kong, Department of Orthopedics and Traumatology, Prince of Wales Hospital, Shatin, NT, Hong Kong SAR (China)

    2013-02-15

    To investigate the diagnostic accuracy of oblique axial intermediate weighting MR imaging in detecting partial thickness anterior cruciate ligament (ACL) bundle tears. The study protocol was approved by the institutional ethics committee. Sixty-one subjects (43 male, 18 female; mean age 27.4 years; range 9 to 57 years) with clinically suspected ACL tear or meniscal tear between September 2009 and January 2011 were studied with MRI and arthroscopy. Detection of partial tear for the ACL as a whole and for each ACL bundle by protocol A (standard orthogonal sequences) and protocol B (standard orthogonal sequences plus oblique axial intermediate weighted imaging) was compared in a blinded fashion. Performance characteristics for protocol A and protocol B were compared using sensitivity, specificity, accuracy and ROC curves. A two-tailed p value of <0.05 indicated statistical significance. Fifteen (24.6%) normal, 15 (24.6%) partial and 31 complete tears were diagnosed by arthroscopy. Sensitivity, specificity and accuracy of protocol A for the diagnosis of partial tear of the ACL was 33%, 87% and 74%, while for protocol B the values were 87%, 87% and 87% respectively. The area under the curve (AUC) for the diagnosis of partial ACL tear and individual bundle tear was higher for protocol B, although this difference did not reach statistical significance (p > 0.05). The addition of oblique axial imaging to standard MR imaging improves diagnostic accuracy for detecting partial tears of the ACL as well as individual bundle tears of the ACL. (orig.)

  13. MR imaging of meniscal subluxation in the knee

    International Nuclear Information System (INIS)

    Breitenseher, M.J.; Tratting, S.; Dobrocky, I.; Steiner, E.; Imhof, H.; Kukla, C.; Nehrer, S.

    1997-01-01

    Purpose: The aim of this study was to establish diagnostic criteria for meniscal subluxation, and to determine whether there was any connection between meniscal subluxation and other common meniscal and knee-joint abnormalities. Material and Methods: The normal position of the meniscal body was assessed in 10 asymptomatic volunteers. MR signs of meniscal subluxation were evaluated retrospectively in 60 symptomatic patients with pain the knee, impaired mobility, and/or joint swelling who had no clear diagnosis after the evaluation of case history, clinical examination, and radiography. The criterion for subluxation of the meniscus was defined as a distance of ≥3 mm between the peripheral border of the meniscus and the edge of the tibial plateau. Results: In the volunteers, the mean distance form the medial meniscus to the edge of the tibial plateau was 0.07 mm, and that from the lateral meniscus was 0 mm. In 55 symptomatic patients without meniscal subluxation, the mean distance from the meniscus to the edge of the tribial plateau was 0.27 mm. Five patients (8%) had evidence of meniscal subluxation, 4 in the medial meniscus and one in the lateral meniscus. The most commonly associated knee abnormality was joint effusion in 5 knees and osteoarthritis in 2 knees. Conclusion: Meniscal subluxation was not a rare finding with MR imaging in patients with painful knees. Meniscal subluxation was associated with other knee abnormalities such as joint effusion or osteoarthritis. (orig.)

  14. Meniscal repair following meniscectomy: Mechanism and protective effect

    International Nuclear Information System (INIS)

    Berjon, J.J.; Munuera, L.; Calvo, M.

    1990-01-01

    Meniscal repair was studied to evaluate the mechanism and its potential protective effects on the articular cartilage in an experimental model consisting of 68 knees of adult dogs on which five different types of medial meniscectomy were performed. The results were assessed by macroscopic, microangiographic, and histological methods, after a sequential follow-up period of 10-450 days. Two different mechanisms of meniscal repair were observed, depending on whether meniscal section had been performed in vascular (total meniscectomy) or avascular (subtotal or partial meniscectomy) zones. It was also observed that the repaired meniscal tissue does not prevent articular cartilage degeneration. This is more closely related to the size of the meniscal fragment preserved at meniscetomy. Due to the biomechanical importance of the meniscus and the lack of functional relevance of the repaired meniscal tissue, the most conservative approach possible to meniscectomy is recommended. (orig.)

  15. Fat-suppressed volume isotropic turbo spin echo acquisition (VISTA) MR imaging in evaluating radial and root tears of the meniscus: Focusing on reader-defined axial reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Daekeon; Lee, Young Han; Kim, Sungjun; Song, Ho-Taek; Suh, Jin-Suck, E-mail: jss@yuhs.ac

    2013-12-01

    Objective: To assess the diagnostic value of fat-suppressed (FS) three-dimensional (3D) volume isotropic turbo spin echo acquisition (VISTA) imaging in detecting radial and root tears of the meniscus, including the reader-defined reformatted axial (RDA) plane. Materials and methods: Twenty-three patients with arthroscopically confirmed radial or root tears of the meniscus underwent magnetic resonance imaging (MRI) with 2D and FS 3D VISTA sequences. MRIs were reviewed independently by two musculoskeletal radiologists blinded to the arthroscopic findings. Sensitivity, specificity, accuracy, and interobserver agreement were calculated for radial and root tears. Both radiologists reported confidence scale for the presence of meniscal tears in 2D axial imaging, 3D axial imaging, and RDA imaging, based on a five-point scale. Wilcoxon's signed rank test was used to compare confidence scale. Results: The sensitivity, specificity, and accuracy of FS 3D VISTA MR imaging versus 2D MR imaging were as follows: 96%, 96%, and 96% versus 91%, 91%, and 91%, respectively in reader 1, and 96%, 96%, and 96% versus 83%, 91%, and 87%, respectively, in reader 2. Interobserver agreement for detecting meniscal tears was excellent (κ = 1) with FS 3D VISTA. The confidence scale was significantly higher for 3D axial images than 2D imaging (p = 0.03) and significantly higher in RDA images than 3D axial image in detecting radial and root tears. Conclusions: FS 3D VISTA had a better diagnostic performance in evaluating radial and root tears of the meniscus. The reader-defined reformatted axial plane obtained from FS 3D VISTA MR imaging is useful in detecting radial and root tears of the meniscus.

  16. Advances and Prospects in Tissue-Engineered Meniscal Scaffolds for Meniscus Regeneration

    Directory of Open Access Journals (Sweden)

    Weimin Guo

    2015-01-01

    Full Text Available The meniscus plays a crucial role in maintaining knee joint homoeostasis. Meniscal lesions are relatively common in the knee joint and are typically categorized into various types. However, it is difficult for inner avascular meniscal lesions to self-heal. Untreated meniscal lesions lead to meniscal extrusions in the long-term and gradually trigger the development of knee osteoarthritis (OA. The relationship between meniscal lesions and knee OA is complex. Partial meniscectomy, which is the primary method to treat a meniscal injury, only relieves short-term pain; however, it does not prevent the development of knee OA. Similarly, other current therapeutic strategies have intrinsic limitations in clinical practice. Tissue engineering technology will probably address this challenge by reconstructing a meniscus possessing an integrated configuration with competent biomechanical capacity. This review describes normal structure and biomechanical characteristics of the meniscus, discusses the relationship between meniscal lesions and knee OA, and summarizes the classifications and corresponding treatment strategies for meniscal lesions to understand meniscal regeneration from physiological and pathological perspectives. Last, we present current advances in meniscal scaffolds and provide a number of prospects that will potentially benefit the development of meniscal regeneration methods.

  17. The Monopod Bucket Foundation

    DEFF Research Database (Denmark)

    Bakmar, Christian LeBlanc; Ahle, Kim; Nielsen, Søren A.

    2009-01-01

    Following the successful installation of a prototype of a monopod bucket foundation, also called a “monopod suction caisson”, at Horns Rev 2 Offshore Wind Farm, Denmark, in 2009, DONG Energy is currently developing a commercialization strategy. The monopod bucket foundation is a promising...

  18. Bucket foundations under lateral cyclic loading

    DEFF Research Database (Denmark)

    Foglia, Aligi

    failure envelopes. A jacked installation test is successfully compared with existing models. Tests of bucket foundations under lateral loading applied at different loading rates are analysed. As expected, the bearing capacity of bucket foundations under transient lateral loading increases dramatically...... documents on bearing capacity and installation of bucket foundations are reviewed and the results from the models found in literature are compared to the experimental results obtained in the current study. Monotonic tests of bucket foundations under lateral loading until failure are compared with existing...

  19. Anterior cruciate ligament tears: MRI versus arthroscopy

    International Nuclear Information System (INIS)

    Tosch, U.; Felix, R.; Schauwecker, W.; Dreithaler, B.

    1992-01-01

    Because of suspected rupture of the anterior cruciate ligament sixteen acute traumatised patients were investigated by MR and arthroscopy. The MR diagnosis of a lesion of the anterior cruciate ligament proved to be correct by arthroscopy in fifteen of sixteen cases. Diagnostic criteria for lesions of the anterior cruciate ligament were: increased signal intensity in T 1 - and T 2 weighted images, increased volume and discontinuity of ligamentous structures. Additional MR findings of meniscal tears were correct in three of four cases laterally and in four of four cases medially. Femoral cartilage lesions were correctly identified by MR in three cases. MR normal findings proved to be correct by arthroscopy in another five cases. (orig.) [de

  20. Evaluation of the menisci of the knee joint using three-dimensional isotropic resolution fast spin-echo imaging: diagnostic performance in 250 patients with surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kijowski, Richard; Davis, Kirkland W.; Blankenbaker, Donna G.; Woods, Michael A.; De Smet, Arthur A. [University of Wisconsin School of Medicine and Public Health, Department of Radiology, Madison, WI (United States); Munoz del Rio, Alejandro [University of Wisconsin School of Medicine and Public Health, Department of Radiology, Madison, WI (United States); University of Wisconsin School of Medicine and Public Health, Department of Statistics, Madison, WI (United States)

    2012-02-15

    To compare the diagnostic performance of FSE-Cube, a three-dimensional isotropic resolution intermediate-weighted fast spin-echo sequence, with a routine magnetic resonance (MR) protocol at 3.0 T for detecting surgically confirmed meniscal tears of the knee joint in a large patient population. FSE-Cube was added to a routine MR protocol performed at 3.0 T on 250 patients who underwent subsequent knee arthroscopy. Three radiologists independently used FSE-Cube during one review and the routine MR protocol during a second review to detect medial and lateral meniscal tears. Using arthroscopy as the reference standard, the sensitivity and specificity of FSE-Cube and the routine MR protocol for detecting meniscal tears were determined for all readers combined. McNemar's tests were used to compare diagnostic performance between FSE-Cube and the routine MR protocol. FSE-cube and the routine MR protocol had similar sensitivity (95.5%/95.3% respectively, P=0.94) and similar specificity (69.8%/74.0% respectively, P=0.10) for detecting 156 medial meniscal tears. FSE-Cube had significantly lower sensitivity than the routine MR protocol (79.4%/85.0% respectively, P < 0.05) but similar specificity (83.9%/82.2% respectively, P=0.37) for detecting 89 lateral mensical tears. For lateral meniscal tears, FSE-Cube had significantly lower sensitivity (P < 0.05) than the routine MR protocol for detecting 19 root tears but similar sensitivity (P=0.17-1.00) for detecting all other tear locations and types. FSE-Cube had diagnostic performance similar to a routine MR protocol for detecting meniscal tears except for a significantly lower sensitivity for detecting lateral meniscal tears, which was mainly attributed to decreased ability to identify lateral meniscus root tears. (orig.)

  1. Evaluation of the menisci of the knee joint using three-dimensional isotropic resolution fast spin-echo imaging: diagnostic performance in 250 patients with surgical correlation

    International Nuclear Information System (INIS)

    Kijowski, Richard; Davis, Kirkland W.; Blankenbaker, Donna G.; Woods, Michael A.; De Smet, Arthur A.; Munoz del Rio, Alejandro

    2012-01-01

    To compare the diagnostic performance of FSE-Cube, a three-dimensional isotropic resolution intermediate-weighted fast spin-echo sequence, with a routine magnetic resonance (MR) protocol at 3.0 T for detecting surgically confirmed meniscal tears of the knee joint in a large patient population. FSE-Cube was added to a routine MR protocol performed at 3.0 T on 250 patients who underwent subsequent knee arthroscopy. Three radiologists independently used FSE-Cube during one review and the routine MR protocol during a second review to detect medial and lateral meniscal tears. Using arthroscopy as the reference standard, the sensitivity and specificity of FSE-Cube and the routine MR protocol for detecting meniscal tears were determined for all readers combined. McNemar's tests were used to compare diagnostic performance between FSE-Cube and the routine MR protocol. FSE-cube and the routine MR protocol had similar sensitivity (95.5%/95.3% respectively, P=0.94) and similar specificity (69.8%/74.0% respectively, P=0.10) for detecting 156 medial meniscal tears. FSE-Cube had significantly lower sensitivity than the routine MR protocol (79.4%/85.0% respectively, P < 0.05) but similar specificity (83.9%/82.2% respectively, P=0.37) for detecting 89 lateral mensical tears. For lateral meniscal tears, FSE-Cube had significantly lower sensitivity (P < 0.05) than the routine MR protocol for detecting 19 root tears but similar sensitivity (P=0.17-1.00) for detecting all other tear locations and types. FSE-Cube had diagnostic performance similar to a routine MR protocol for detecting meniscal tears except for a significantly lower sensitivity for detecting lateral meniscal tears, which was mainly attributed to decreased ability to identify lateral meniscus root tears. (orig.)

  2. Static Behaviour of Bucket Foundations

    DEFF Research Database (Denmark)

    Larsen, Kim André

    One new foundation concept in relation to offshore wind turbines is bucket foundations. The concept is known from the oil and gas industry, though the load conditions here are significantly different. The bucket foundation can be used as monopod or e.g. tripod foundations for offshore wind turbines....... The monopod concept is investigated in this thesis, regarding the static behaviour from loads relevant to offshore wind turbines. The main issue in this concept is the rotational stiffness of the foundation and the combined capacity dominated by moments. The vertical bearing capacity of bucket foundations...... theory is proposed. The proposed expression applies to plane strain as well as axis-symmetric stress conditions for foundations with smooth or rough bases. A thorough experimental investigation of the static behaviour of bucket foundations subjected to combined loading is carried out. Laboratory tests...

  3. PERANCANGAN PROTOTIPE BUCKET ELEVATOR

    OpenAIRE

    Dani Irawan

    2017-01-01

    Alat Pemindah Bahan merupakan salah satu peralatan yang digunakan untuk kegiatan sehari-hari pada proses keberlangsungan produksi di masyarakat. Agar peralatan tersebut tetap dapat berfungsi dengan baik masyarakat, maka perlu adanya tindakan rancang bangun prototype Bucket konveyor ini guna untuk membatu masyarakat agar lebih memahami betapa pentingnya alat mekanis. Metode Perancangan Prototipe Bucket Konveyor meliputi: Perancangan Desain, Perancangan Elemen Mesin Perancangan Biaya (biaya...

  4. Meniscal shear stress for punching.

    Science.gov (United States)

    Tuijthof, Gabrielle J M; Meulman, Hubert N; Herder, Just L; van Dijk, C Niek

    2009-01-01

    Experimental determination of the shear stress for punching meniscal tissue. Meniscectomy (surgical treatment of a lesion of one of the menisci) is the most frequently performed arthroscopic procedure. The performance of a meniscectomy is not optimal with the currently available instruments. To design new instruments, the punching force of meniscal tissue is an important parameter. Quantitative data are unavailable. The meniscal punching process was simulated by pushing a rod through meniscal tissue at constant speed. Three punching rods were tested: a solid rod of Oslash; 3.00 mm, and two hollow tubes (Oslash; 3.00-2.60 mm) with sharpened cutting edges of 0.15 mm and 0.125 mm thick, respectively. Nineteen menisci acquired from 10 human cadaveric knee joints were punched (30 tests). The force and displacement were recorded from which the maximum shear stress was determined (average added with three times the standard deviation). The maximum shear stress for the solid rod was determined at 10.2 N/mm2. This rod required a significantly lower punch force in comparison with the hollow tube having a 0.15 mm cutting edge (plt;0.01). The maximum shear stress for punching can be applied to design instruments, and virtual reality training environments. This type of experiment is suitable to form a database with material properties of human tissue similar to databases for the manufacturing industry.

  5. Clinical significance of condylar chondromalacia after arthroscopic resection of flap-tears of the medial meniscus. A prospective study of 93 cases.

    Science.gov (United States)

    Aune, A K; Madsen, J E; Moen, H

    1995-01-01

    We describe the results after arthroscopic resection of flap-tears of the medial meniscus posterior horn in 93 patients with (40) or without (53) chondromalacia of the adjacent condylar cartilage at the time of operation. These were 93 consecutive patients presenting with medial flap-tears during the period 1988-1990 in our departments. The follow-up averaged 42 (range 26-50) months. There was a significant difference in the functional results at review depending on the presence or absence of condylar chondromalacia at arthroscopy. Among the 40 patients with chondromalacia, the Lysholm score was significantly lower (P chondromalacia with age (P < 0.001). In conclusion, the presence of minor degenerative changes in the articular cartilage adjacent to meniscal flap-tears correlated with a less favourable outcome.

  6. Buckets: Smart Objects for Digital Libraries

    Science.gov (United States)

    Nelson, Michael L.

    2001-01-01

    Current discussion of digital libraries (DLs) is often dominated by the merits of the respective storage, search and retrieval functionality of archives, repositories, search engines, search interfaces and database systems. While these technologies are necessary for information management, the information content is more important than the systems used for its storage and retrieval. Digital information should have the same long-term survivability prospects as traditional hardcopy information and should be protected to the extent possible from evolving search engine technologies and vendor vagaries in database management systems. Information content and information retrieval systems should progress on independent paths and make limited assumptions about the status or capabilities of the other. Digital information can achieve independence from archives and DL systems through the use of buckets. Buckets are an aggregative, intelligent construct for publishing in DLs. Buckets allow the decoupling of information content from information storage and retrieval. Buckets exist within the Smart Objects and Dumb Archives model for DLs in that many of the functionalities and responsibilities traditionally associated with archives are pushed down (making the archives dumber) into the buckets (making them smarter). Some of the responsibilities imbued to buckets are the enforcement of their terms and conditions, and maintenance and display of their contents.

  7. Association of weight change with progression of meniscal intrasubstance degeneration over 48 months. Data from the Osteoarthritis Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Brandao Guimaraes, Julio [University of California, Musculoskeletal and Quantitative Imaging Research Group (MQIR), Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Federal University of Sao Paulo (UNIFESP), Department of Radiology, Sao Paulo (Brazil); DASA Laboratory, Department of Radiology, Sao Paulo (Brazil); Nevitt, Michael C.; McCulloch, Charles E.; Liu, Felix [University of California, Department of Epidemiology and Biostatistics, San Francisco, CA (United States); Schwaiger, Benedikt J.; Gersing, Alexandra S.; Facchetti, Luca; Bucknor, Matthew D.; Chanchek, Nattagan; Joseph, Gabby B.; Link, Thomas M. [University of California, Musculoskeletal and Quantitative Imaging Research Group (MQIR), Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

    2018-03-15

    To investigate the association of weight change over 48 months with progression of meniscal intrasubstance degeneration (MID). We studied 487 subjects with MID at baseline and after 48 months using 3-T MRI with the same protocol (FSE sequences with and without fat suppression). These participants lost weight (≥3%, n = 141), had moderate weight gain (3-10%, n = 77), substantial weight gain (>10%, n = 15) or maintained stable weight (n = 254). Progression of MID to a meniscal tear was assessed using the WORMS grading system and compared among weight change groups using logistic regression. ANOVA and chi-square tests were used to study the differences in subjects' characteristics. Progression of MID increased from weight loss to substantial weight gain (p < 0.001) and was significantly more likely with both moderate weight gain (odds ratio [OR], 4.9; 95% confidence interval [CI] 2.4-8.9) and substantial weight gain (OR, 9.5; 95% CI 3.2-28.5) compared to stable weight. Results were similar in both menisci for moderate weight gain (medial: OR, 6.8; 95% CI 3.5-11.3; lateral: OR, 2.6; 95% CI 1.1-6.6) and substantial weight gain (medial: OR, 21.0; 95% CI 5.1-80.7; lateral: OR, 9.7; 95% CI 0.95-100.2). Weight gain is associated with an increased likelihood that meniscal intrasubstance degeneration will progress with the risk increasing with greater weight gain. (orig.)

  8. Anterolateral ligament abnormalities in patients with acute anterior cruciate ligament rupture are associated with lateral meniscal and osseous injuries

    Energy Technology Data Exchange (ETDEWEB)

    Dyck, Pieter van; Smet, Eline de; Gielen, Jan L.; Parizel, Paul M. [Antwerp University Hospital and University of Antwerp, Department of Radiology, Antwerp (Belgium); Clockaerts, Stefan [University College Hospitals, Department of Orthopaedics, London (United Kingdom); Vanhoenacker, Filip M. [Antwerp University Hospital and University of Antwerp, Department of Radiology, Antwerp (Belgium); Ghent University Hospital and University of Ghent, Department of Radiology, Ghent (Belgium); AZ St-Maarten, Department of Radiology, Antwerp (Belgium); Lambrecht, Valerie [Ghent University Hospital and University of Ghent, Department of Radiology, Ghent (Belgium); Wouters, Kristien [Antwerp University Hospital and University of Antwerp, Department of Biostatistics, Antwerp (Belgium)

    2016-10-15

    To determine the frequency of anterolateral ligament (ALL) injury in patients with acute anterior cruciate ligament (ACL) rupture and to analyse its associated injury patterns. Ninety patients with acute ACL rupture for which MRI was obtained within 8 weeks after the initial trauma were retrospectively identified. Two radiologists assessed the status of the ALL on MRI by consensus. The presence or absence of an ALL abnormality was compared with the existence of medial and lateral meniscal tears diagnosed during arthroscopy. Associated collateral ligament and osseous injuries were documented with MRI. Forty-one of 90 knees (46 %) demonstrated ALL abnormalities on MRI. Of 49 knees with intact ALL, 15 (31 %) had a torn lateral meniscus as compared to 25 torn lateral menisci in 41 knees (61 %) with abnormal ALL (p = 0.008). Collateral ligament (p ≤ 0.05) and osseous injuries (p = 0.0037) were more frequent and severe in ALL-injured as compared with ALL-intact knees. ALL injuries are fairly common in patients with acute ACL rupture and are statistically significantly associated with lateral meniscal, collateral ligament and osseous injuries. (orig.)

  9. Arthroscopic Meniscal Allograft Transplantation With Soft-Tissue Fixation Through Bone Tunnels.

    Science.gov (United States)

    Spalding, Tim; Parkinson, Ben; Smith, Nick A; Verdonk, Peter

    2015-10-01

    Meniscal allograft transplantation improves clinical outcomes for patients with symptomatic meniscus-deficient knees. We describe an established arthroscopic technique for meniscal allograft transplantation without the need for bone fixation of the meniscal horns. After preparation of the meniscal bed, the meniscus is parachuted into the knee through a silicone cannula and the meniscal horns are fixed with sutures through bone tunnels. The body of the meniscus is then fixed with a combination of all-inside and inside-out sutures. This technique is reliable and reproducible and has clinical outcomes comparable with those of bone plug fixation techniques.

  10. Optimizing chain life in bucket elevators through proper design and elongation measurement

    Energy Technology Data Exchange (ETDEWEB)

    Luglio, J.J. [Rexnord, Inc., Milwaukee, WI (United States)

    2001-04-01

    Since down time in the bulk solids handling industry is so expensive, bucket elevators must operate with extreme reliability, and, of course, the cost per ton of material conveyed must be minimized. This means balancing initial costs, operating and maintenance costs as well as minimizing the inventory of parts required in order to insure reliability. The elevator must be designed properly for each application. It must also be operated and maintained properly. (orig.)

  11. Characteristic Behavior of Bucket Foundations

    DEFF Research Database (Denmark)

    Barari, Amin

    and gas industry and have recently been used in offshore wind turbines. The bucket foundation is a welded steel structure consisting of a tubular center column connected to a steel bucket through flange-reinforced stiffeners. The overall aim of the research presented in this thesis was to improve...

  12. MR imaging of the knee following cruciate ligament reconstruction and meniscal surgery; MRT des Kniegelenks nach Kreuzband- und Meniskusoperationen

    Energy Technology Data Exchange (ETDEWEB)

    Woertler, K. [Technische Univ. Muenchen, Klinikum rechts der Isar (Germany). Inst. fuer Roentgendiagnostik

    2009-03-15

    Due to the increasing number of surgical procedures performed on the knee, MR imaging of the postoperative knee has gained more and more importance. For the evaluation of anterior cruciate ligament grafts and postoperative menisci, basic knowledge of surgical techniques is essential in order to differentiate normal postoperative findings from transplant failure, retears, and complications. This article reviews technical aspects of MR imaging following knee surgery, basic principles of operative techniques for anterior cruciate ligament reconstruction and therapy of meniscal tears, normal postoperative findings, MR imaging criteria for recurrent lesions, and findings with typical complications. (orig.)

  13. Meniscal Allograft Transplantation: State of the Art.

    Science.gov (United States)

    Trentacosta, Natasha; Graham, William C; Gersoff, Wayne K

    2016-06-01

    Meniscal allograft transplantation has evolved over the years to provide a state-of-the-art technique for the sports medicine surgeon to utilize in preserving contact mechanics and function of the knee in irreparable meniscal pathology. However, this procedure continues to spark considerable debate on proper tissue processing techniques, acceptable indications, methods of implantation, and potential long-term outcomes.

  14. Use of porous polyurethanes for meniscal reconstruction and meniscal prostheses

    NARCIS (Netherlands)

    deGroot, JH; deVrijer, R; Pennings, AJ; Veth, RPH; Jansen, HWB

    In the past, porous materials made of an aromatic polyurethane (PU) were successfully used for meniscal reconstruction in dogs. Since aromatic PUs yield very toxic fragments upon degradation, a linear PU was synthesized by curing a poly(epsilon-caprolactone) and 1,4-trans-cyclohexane diisocyanate I

  15. Proton density-weighted MR imaging of the knee: fat suppression versus without fat suppression

    Energy Technology Data Exchange (ETDEWEB)

    Lee, So-Yeon; Kim, Sun Ki [Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, Seoul (Korea, Republic of); Jee, Won-Hee [Catholic University of Korea, Department of Radiology, Seoul St. Mary' s Hospital, Seoul (Korea, Republic of); Catholic University of Korea, Diagnostic Radiology, Seoul St. Mary' s Hospital, School of Medicine, Seoul (Korea, Republic of); Kim, Jung-Man [Catholic University of Korea, Department of Orthopedic Surgery, Seoul St. Mary' s Hospital, Seoul (Korea, Republic of)

    2011-02-15

    To prospectively evaluate the diagnostic accuracy of proton density-weighted imaging with and without fat suppression for detecting meniscal tears. The study involved 48 patients who underwent arthroscopy less than 3 months after proton density-weighted imaging with and without fat suppression. Sagittal images were independently reviewed by two radiologists for the presence of meniscal tears. Medial and lateral menisci were separately analyzed in terms of anterior horn, body, and posterior horn. Interobserver agreement was assessed using {kappa} coefficients. The McNemar test was used to determine any differences between the two methods in terms of sensitivity and specificity. Arthroscopy findings were used as the diagnostic reference standard. Arthroscopy revealed 71 tears involving 85 meniscal segments: 34 medial meniscal segments and 51 lateral meniscal segments. The sensitivity, specificity, and accuracy of each radiologist were 95% (81/85), 92% (186/203), and 93% (267/288), and 93% (79/85), 93% (189/203), and 93% (268/288) when using fat-suppressed proton density-weighted imaging, and 91% (77/85), 93% (189/203), and 92% (266/288), and 91% (77/85), 93% (188/203), and 92% (265/288) when using proton density-weighted imaging without fat suppression, respectively. Interobserver agreement for meniscal tears was very high with proton-weighted imaging with ({kappa} = 0.87) or without ({kappa} = 0.86) fat suppression. There were no significant differences for detection of medial meniscal tears when using proton density-weighted imaging with or without fat suppression for both readers (p > 0.05). Fat-suppressed proton density-weighted imaging can replace proton density-weighted imaging without fat suppression for the detection of meniscal tears. (orig.)

  16. Proton density-weighted MR imaging of the knee: fat suppression versus without fat suppression

    International Nuclear Information System (INIS)

    Lee, So-Yeon; Kim, Sun Ki; Jee, Won-Hee; Kim, Jung-Man

    2011-01-01

    To prospectively evaluate the diagnostic accuracy of proton density-weighted imaging with and without fat suppression for detecting meniscal tears. The study involved 48 patients who underwent arthroscopy less than 3 months after proton density-weighted imaging with and without fat suppression. Sagittal images were independently reviewed by two radiologists for the presence of meniscal tears. Medial and lateral menisci were separately analyzed in terms of anterior horn, body, and posterior horn. Interobserver agreement was assessed using κ coefficients. The McNemar test was used to determine any differences between the two methods in terms of sensitivity and specificity. Arthroscopy findings were used as the diagnostic reference standard. Arthroscopy revealed 71 tears involving 85 meniscal segments: 34 medial meniscal segments and 51 lateral meniscal segments. The sensitivity, specificity, and accuracy of each radiologist were 95% (81/85), 92% (186/203), and 93% (267/288), and 93% (79/85), 93% (189/203), and 93% (268/288) when using fat-suppressed proton density-weighted imaging, and 91% (77/85), 93% (189/203), and 92% (266/288), and 91% (77/85), 93% (188/203), and 92% (265/288) when using proton density-weighted imaging without fat suppression, respectively. Interobserver agreement for meniscal tears was very high with proton-weighted imaging with (κ = 0.87) or without (κ = 0.86) fat suppression. There were no significant differences for detection of medial meniscal tears when using proton density-weighted imaging with or without fat suppression for both readers (p > 0.05). Fat-suppressed proton density-weighted imaging can replace proton density-weighted imaging without fat suppression for the detection of meniscal tears. (orig.)

  17. The Value of History, Physical Examination, and Radiographic Findings in the Diagnosis of Symptomatic Meniscal Tear among Middle-Age Subjects with Knee Pain

    Science.gov (United States)

    Katz, Jeffrey N.; Smith, Savannah R.; Yang, Heidi Y.; Martin, Scott D.; Wright, John; Donnell-Fink, Laurel A.; Losina, Elena

    2016-01-01

    Objective To evaluate the utility of clinical history, radiographic and physical exam findings in the diagnosis of symptomatic meniscal tear (SMT) in patients over age 45, in whom concomitant osteoarthritis is prevalent. Methods In a cross-sectional study of patients from two orthopedic surgeons’ clinics we assessed clinical history, physical examination and radiographic findings in patients over 45 with knee pain. The orthopedic surgeons rated their confidence that subjects’ symptoms were due to MT; we defined the diagnosis of SMT as at least 70% confidence. We used logistic regression to identify factors independently associated with diagnosis of SMT and we used the regression results to construct an index of the likelihood of SMT. Results In 174 participants, six findings were associated independently with the expert clinician having ≥70% confidence that symptoms were due to MT: localized pain, ability to fully bend the knee, pain duration <1 year, lack of varus alignment, lack of pes planus, and absence of joint space narrowing on radiographs. The index identified a low risk group with 3% likelihood of SMT. Conclusion While clinicians traditionally rely upon mechanical symptoms in this diagnostic setting, our findings did not support the conclusion that mechanical symptoms were associated with the expert’s confidence that symptoms were due to MT. An index that includes history of localized pain, full flexion, duration <1 year, pes planus, varus alignment, and joint space narrowing can be used to stratify patients according to their risk of SMT and it identifies a subgroup with very low risk. PMID:27390312

  18. Stability of barrier buckets with zero RF-barrier separations

    Energy Technology Data Exchange (ETDEWEB)

    Ng, K.Y.; /Fermilab

    2005-03-01

    A barrier bucket with very small separation between the rf barriers (relative to the barrier widths) or even zero separation has its synchrotron tune decreasing rather slowly from a large value towards the boundary of the bucket. As a result, large area at the bucket edges can become unstable under the modulation of rf voltage and/or rf phase. In addition, chaotic regions may form near the bucket center and extend outward under increasing modulation. Application is made to those barrier buckets used in the process of momentum mining at the Fermilab Recycler Ring.

  19. Second-stage turbine bucket airfoil

    Science.gov (United States)

    Wang, John Zhiqiang; By, Robert Romany; Sims, Calvin L.; Hyde, Susan Marie

    2002-01-01

    The second-stage buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in inches in Table I wherein Z is a perpendicular distance from a plane normal to a radius of the turbine centerline and containing the X and Y values with the Z value commencing at zero in the X, Y plane at the radially innermost aerodynamic section of the airfoil and X and Y are coordinate values defining the airfoil profile at each distance Z. The X and Y values may be scaled as a function of the same constant or number to provide a scaled-up or scaled-down airfoil section for the bucket. The second-stage wheel has sixty buckets.

  20. Three-Tesla magnetic resonance imaging of the meniscus of the knee: What about equivocal errors?

    International Nuclear Information System (INIS)

    Dyck, Pieter van; Vanhoenacker, Filip M.; Gielen, Jan L.; Parizel, Paul M.; Dossche, Lieven; Weyler, Joost

    2010-01-01

    Background: The significance of borderline magnetic resonance (MR) findings that are equivocal for a tear of the knee meniscus remains uncertain. Given their higher signal-to-noise ratio (SNR) and greater spatial resolution, these equivocal meniscal tears could be expected to be less frequent using a 3.0T MR system. Purpose: To investigate the prevalence of equivocal meniscal tears using 3.0T MR, and to study their impact on MR accuracy compared with arthroscopy in the detection of meniscal tears. Material and Methods: The medical records of 100 patients who underwent 3.0T MR imaging and subsequent arthroscopy of the knee were retrospectively reviewed. Two observers interpreted MR images in consensus, and menisci were diagnosed as torn (abnormality on two or more images), equivocal for a tear (abnormality on one image), or intact, using arthroscopy as the standard of reference. The prevalence of equivocal meniscal tears was assessed, and MR accuracy was calculated as follows: first, considering both torn menisci and equivocal diagnoses as positive for a tear; and second, considering only torn menisci as positive for a tear. Results: Evidence of meniscal tears on MR images was equivocal in 12 medial (12%) and three lateral (3%) menisci. Of these equivocal MR diagnoses, tears were found at arthroscopy in eight medial and one lateral meniscus. In our study, the specificity and positive predictive value increased for both the medial and lateral meniscus when only menisci with two or more abnormal images were considered to be torn: from 80% and 89% to 91% and 94% for the medial meniscus, and from 91% and 73% to 93% and 78% for the lateral meniscus, respectively. Conclusion: Subtle findings that are equivocal for a tear of the knee meniscus still make MR diagnosis difficult, even at 3.0T. We recommend that radiologists should rather be descriptive in reporting subtle or equivocal MR findings, alerting the clinician of possible meniscal tear

  1. Three-Tesla magnetic resonance imaging of the meniscus of the knee: What about equivocal errors?

    Energy Technology Data Exchange (ETDEWEB)

    Dyck, Pieter van; Vanhoenacker, Filip M.; Gielen, Jan L.; Parizel, Paul M. (Dept. of Radiology, Univ. Hospital Antwerp and Univ. of Antwerp, Antwerp (Edegem) (Belgium)), e-mail: pieter.van.dyck@uza.be; Dossche, Lieven (Dept. of Orthopedics, Univ. Hospital Antwerp and Univ. of Antwerp, Antwerp (Edegem) (Belgium)); Weyler, Joost (Dept. of Epidemiology and Social Medicine, Univ. of Antwerp, Antwerp (Wilrijk) (Belgium))

    2010-04-15

    Background: The significance of borderline magnetic resonance (MR) findings that are equivocal for a tear of the knee meniscus remains uncertain. Given their higher signal-to-noise ratio (SNR) and greater spatial resolution, these equivocal meniscal tears could be expected to be less frequent using a 3.0T MR system. Purpose: To investigate the prevalence of equivocal meniscal tears using 3.0T MR, and to study their impact on MR accuracy compared with arthroscopy in the detection of meniscal tears. Material and Methods: The medical records of 100 patients who underwent 3.0T MR imaging and subsequent arthroscopy of the knee were retrospectively reviewed. Two observers interpreted MR images in consensus, and menisci were diagnosed as torn (abnormality on two or more images), equivocal for a tear (abnormality on one image), or intact, using arthroscopy as the standard of reference. The prevalence of equivocal meniscal tears was assessed, and MR accuracy was calculated as follows: first, considering both torn menisci and equivocal diagnoses as positive for a tear; and second, considering only torn menisci as positive for a tear. Results: Evidence of meniscal tears on MR images was equivocal in 12 medial (12%) and three lateral (3%) menisci. Of these equivocal MR diagnoses, tears were found at arthroscopy in eight medial and one lateral meniscus. In our study, the specificity and positive predictive value increased for both the medial and lateral meniscus when only menisci with two or more abnormal images were considered to be torn: from 80% and 89% to 91% and 94% for the medial meniscus, and from 91% and 73% to 93% and 78% for the lateral meniscus, respectively. Conclusion: Subtle findings that are equivocal for a tear of the knee meniscus still make MR diagnosis difficult, even at 3.0T. We recommend that radiologists should rather be descriptive in reporting subtle or equivocal MR findings, alerting the clinician of possible meniscal tear

  2. Suction Buckets

    DEFF Research Database (Denmark)

    Feld, T.

    Friction Model, are implemented as user defined material models in the commercial finite element program ABAQUS. The simulated tests are partly pullout tests, subsequent cyclic loading, partly drained tests on buckets subject to vertical, horizontal and moment loading. The numerical analyses are capable...

  3. Numerical analysis of the bucket surface roughness effects in Pelton turbine

    International Nuclear Information System (INIS)

    Xiao, Y X; Zeng, C J; Zhang, J; Yan, Z G; Wang, Z W

    2013-01-01

    The internal flow of a Pelton turbine is quite complex. It is difficult to analyse the unsteady free water sheet flow in the rotating bucket owing to the lack of a sound theory. Affected by manufacturing technique and silt abrasion during the operation, the bucket surface roughness of Pelton turbine may be too great, and thereby influence unit performance. To investigate the effect of bucket roughness on Pelton turbine performance, this paper presents the numerical simulation of the interaction between the jet and the bucket in a Pelton turbine. The unsteady three-dimensional numerical simulations were performed with CFX code by using the SST turbulence model coupling the two-phase flow volume of fluid method. Different magnitude orders of bucket surface roughness were analysed and compared. Unsteady numerical results of the free water sheet flow patterns on bucket surface, torque and unit performance for each bucket surface roughness were generated. The total pressure distribution on bucket surface is used to show the free water sheet flow pattern on bucket surface. By comparing the variation of water sheet flow patterns on bucket surface with different roughness, this paper qualitatively analyses how the bucket surface roughness magnitude influences the impeding effect on free water sheet flow. Comparison of the torque variation of different bucket surface roughness highlighted the effect of the bucket surface roughness on the Pelton turbine output capacity. To further investigate the effect of bucket surface roughness on Pelton turbine performance, the relation between the relative efficiency loss rate and bucket surface roughness magnitude is quantitatively analysed. The result can be used to predict and evaluate the Pelton turbine performance

  4. Numerical analysis of the bucket surface roughness effects in Pelton turbine

    Science.gov (United States)

    Xiao, Y. X.; Zeng, C. J.; Zhang, J.; Yan, Z. G.; Wang, Z. W.

    2013-12-01

    The internal flow of a Pelton turbine is quite complex. It is difficult to analyse the unsteady free water sheet flow in the rotating bucket owing to the lack of a sound theory. Affected by manufacturing technique and silt abrasion during the operation, the bucket surface roughness of Pelton turbine may be too great, and thereby influence unit performance. To investigate the effect of bucket roughness on Pelton turbine performance, this paper presents the numerical simulation of the interaction between the jet and the bucket in a Pelton turbine. The unsteady three-dimensional numerical simulations were performed with CFX code by using the SST turbulence model coupling the two-phase flow volume of fluid method. Different magnitude orders of bucket surface roughness were analysed and compared. Unsteady numerical results of the free water sheet flow patterns on bucket surface, torque and unit performance for each bucket surface roughness were generated. The total pressure distribution on bucket surface is used to show the free water sheet flow pattern on bucket surface. By comparing the variation of water sheet flow patterns on bucket surface with different roughness, this paper qualitatively analyses how the bucket surface roughness magnitude influences the impeding effect on free water sheet flow. Comparison of the torque variation of different bucket surface roughness highlighted the effect of the bucket surface roughness on the Pelton turbine output capacity. To further investigate the effect of bucket surface roughness on Pelton turbine performance, the relation between the relative efficiency loss rate and bucket surface roughness magnitude is quantitatively analysed. The result can be used to predict and evaluate the Pelton turbine performance.

  5. Vertical tears of the cranial horn of the meniscus and its cranial ligament in the equine femorotibial joint: 7 cases and their treatment by arthroscopic surgery.

    Science.gov (United States)

    Walmsley, J P

    1995-01-01

    Five horses with a vertical tear in the cranial horn and cranial ligament of the medial meniscus and 2 horses with a similar injury in the lateral meniscus were diagnosed from a series of 126 horses which were examined arthroscopically for stifle lameness. All the lesions had similar characteristics. The tear was about 1 cm from the axial border of the meniscus and its ligament and, in all but one case in which it was incomplete, much of the torn tissue was loosely attached in the axial part of the joint from where it was removed. The remaining meniscus, abaxial to the tear, was displaced cranially and abaxially and its torn edges were debrided. Radiographically, 6 cases had proliferative new bone on the cranial aspect of the intercondylar eminence of the tibia and 3 had calcified soft tissue densities in the cranial, medial or lateral femorotibial joint. Following surgery and a 6 month period of rest and controlled exercise, 3 horses returned to full competition work, one was usable for hacking, 2 are convalescing and one is lame after one year. It is postulated that this could be a characteristic meniscal injury in horses which can benefit from arthroscopic surgery. Better techniques for accessing the body and caudal pole of the menisci are needed if a more complete diagnosis and treatment of meniscal injuries are to be achieved.

  6. Vertical tears of the cranial horn of the meniscus and its cranial ligament in the equine femorotibial joint: 7 cases and their treatment by arthroscopic surgery

    International Nuclear Information System (INIS)

    Walmsley, J.P.

    1995-01-01

    Five horses with a vertical tear in the cranial horn and cranial ligament of the medial meniscus and 2 horses with a similar injury in the lateral meniscus were diagnosed from a series of 126 horses which were examined arthroscopically for stifle lameness. All the lesions had similar characteristics. The tear was about 1 cm from the axial border of the meniscus and its ligament and, in all but one case in which it was incomplete, much of the torn tissue was loosely attached in the axial part of the joint from where it was removed. The remaining meniscus, abaxial to the tear, was displaced cranially and abaxially and its torn edges were debrided. Radiographically, 6 cases had proliferative new bone on the cranial aspect of the intercondylar eminence of the tibia and 3 had calcified soft tissue densities in the cranial, medial or lateral femorotibial joint. Following surgery and a 6 month period of rest and controlled exercise, 3 horses returned to full competition work, one was usable for hacking, 2 are convalescing and one is lame after one year. It is postulated that this could be a characteristic meniscal injury in horses which can benefit from arthroscopic surgery. Better techniques for accessing the body and caudal pole of the menisci are needed if a more complete diagnosis and treatment of meniscal injuries are to be achieved

  7. Meniscal allograft transplantation: a meta-analysis

    Directory of Open Access Journals (Sweden)

    De Bruycker Manolito

    2017-01-01

    Full Text Available Purpose: This meta-analysis evaluates the mid- to long-term survival outcome of MAT (meniscal allograft transplantation. Potential prognosticators, with particular focus on chondral status and age of the patient at the time of transplantation, were also analysed. Study design: Meta-analysis. Methods: An online database search was performed using following search string: “meniscal allograft transplantation” and “outcome”. A total of 65 articles were analysed for a total of 3157 performed MAT with a mean follow-up of 5.4 years. Subjective and clinical data was analysed. Results: The subjective and objective results of 2977 patients (3157 allografts were analysed; 70% were male, 30% were female. Thirty-eight percent received an isolated MAT. All other patients underwent at least one concomitant procedure. Lysholm, Knee injury and Osteoarthritis Outcome (KOOS, International Knee Documentation Committee (IKDC and Visual Analogue Scale (VAS scores were analysed. All scores showed a good patient satisfaction at long-term follow-up. The mean overall survival rate was 80.9%. Complication rates were comparable to standard meniscal repair surgery. There was a degenerative evolution in osteoarthritis with at least one grade in 1760 radiographically analysed patients. Concomitant procedures seem to have no effect on the outcome. Age at transplantation is a negative prognosticator. The body mass index (BMI of the patient shows a slightly negative correlation with the outcome of MAT. Conclusions: MAT is a viable solution for the younger patient with chronic pain in the meniscectomised knee joint. The complications are not severe and comparable to meniscal repair. The overall failure rate at final follow-up is acceptable and the allograft heals well in most cases, but MAT cannot be seen as a definitive solution for post-meniscectomy pain. The correct approach to the chronic painful total meniscectomised knee joint thus requires consideration of all

  8. recurrent traumatic posterior hip dislocation in labral avulsion

    African Journals Online (AJOL)

    2003; 54(3):520-529. 5. Dameron, T.B Jr. Bucket-handle tear of acetabular labrum accompanying posterior dislocation of the hip. J Bone Joint Surg Am. 1959; 41(1): 131-134. 6. Lieberman, J.R., Altchek, D.W. and Salvati,. E.A. Recurrent dislocation of a hip with a labral lesion: treatment with a modified Bankart-type repair.

  9. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Pawelec, K. M., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E. [Cambridge Centre for Medical Materials, Materials Science and Metallurgy Department, University of Cambridge, Cambridge CB3 0FS (United Kingdom); Wardale, R. J., E-mail: pawelec.km@gmail.com, E-mail: jw626@cam.ac.uk [Division of Trauma and Orthopaedic Surgery, Department of Surgery, University of Cambridge, Cambridge CB2 2QQ (United Kingdom)

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  10. Effective Treatment of an Apparent Meniscal Injury Using the Mulligan Concept

    Directory of Open Access Journals (Sweden)

    Alex J. Rhinehart

    2015-05-01

    Full Text Available Objective: Present a clinic case demonstrating the effectiveness of the Mulligan Concept (MC in treating an apparent meniscal injury. The utilization of the MC in the evaluation and treatment of a 20-year-old soccer player with an apparent acute meniscal injury is presented. Background: Meniscal injuries are common knee injuries. The MC is a therapeutic intervention strategy applied as both a treatment-based evaluation and therapeutic intervention. Treatment: The patient was successfully treated in four treatment sessions using the MC. The patient experienced minimal clinically-important differences on a variety of global and regional patient-rated outcomes. Uniqueness: To the author’s knowledge, there are currently no published case reports of using the MC in clinical practice to treat an apparent meniscal pathology. Conclusion: The MC can be utilized as an evaluation and treatment technique in patients suspected of having meniscal pathology in the knee.

  11. Defining the Value of Future Research to Identify the Preferred Treatment of Meniscal Tear in the Presence of Knee Osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Elena Losina

    Full Text Available Arthroscopic partial meniscectomy (APM is extensively used to relieve pain in patients with symptomatic meniscal tear (MT and knee osteoarthritis (OA. Recent studies have failed to show the superiority of APM compared to other treatments. We aim to examine whether existing evidence is sufficient to reject use of APM as a cost-effective treatment for MT+OA.We built a patient-level microsimulation using Monte Carlo methods and evaluated three strategies: Physical therapy ('PT' alone; PT followed by APM if subjects continued to experience pain ('Delayed APM'; and 'Immediate APM'. Our subject population was US adults with symptomatic MT and knee OA over a 10 year time horizon. We assessed treatment outcomes using societal costs, quality-adjusted life years (QALYs, and calculated incremental cost-effectiveness ratios (ICERs, incorporating productivity costs as a sensitivity analysis. We also conducted a value-of-information analysis using probabilistic sensitivity analyses.Calculated ICERs were estimated to be $12,900/QALY for Delayed APM as compared to PT and $103,200/QALY for Immediate APM as compared to Delayed APM. In sensitivity analyses, inclusion of time costs made Delayed APM cost-saving as compared to PT. Improving efficacy of Delayed APM led to higher incremental costs and lower incremental effectiveness of Immediate APM in comparison to Delayed APM. Probabilistic sensitivity analyses indicated that PT had 3.0% probability of being cost-effective at a willingness-to-pay (WTP threshold of $50,000/QALY. Delayed APM was cost effective 57.7% of the time at WTP = $50,000/QALY and 50.2% at WTP = $100,000/QALY. The probability of Immediate APM being cost-effective did not exceed 50% unless WTP exceeded $103,000/QALY.We conclude that current cost-effectiveness evidence does not support unqualified rejection of either Immediate or Delayed APM for the treatment of MT+OA. The amount to which society would be willing to pay for additional information

  12. Tubing vs. buckets: a cost comparison

    Science.gov (United States)

    Neil K. Huyler

    1975-01-01

    Equipment investment for tubing-vacuum systems was significantly less than that for bucket systems. Tubing-vacuum systems required about 22 percent less labor input, the major labor input being completed before sap-flow periods. Annual cost of operation was less for tubing-vacuum than the bucket system. Small tubing-vacuum operations showed more profit potential than...

  13. MRI follow-up of conservatively treated meniscal knee lesions in general practice

    Energy Technology Data Exchange (ETDEWEB)

    Oei, Edwin H.G.; Hunink, M.G.M. [University Medical Center Rotterdam, Program for the Assessment of Radiological Technology (ART Program), Erasmus MC, Rotterdam (Netherlands); University Medical Center Rotterdam, Department of Radiology, Erasmus MC, Rotterdam (Netherlands); University Medical Center Rotterdam, Department of Epidemiology, Erasmus MC, Rotterdam (Netherlands); Koster, Ingrid M. [University Medical Center Rotterdam, Department of Radiology, Erasmus MC, Rotterdam (Netherlands); Maasstad Ziekenhuis, Department of Radiology, Rotterdam (Netherlands); Hensen, Jan-Hein J.; Vroegindeweij, Dammis [Maasstad Ziekenhuis, Department of Radiology, Rotterdam (Netherlands); Boks, Simone S. [University Medical Center Rotterdam, Department of General Practice, Erasmus MC, Rotterdam (Netherlands); Maasstad Ziekenhuis, Department of Radiology, Rotterdam (Netherlands); Diaconessenhuis Meppel, Department of Radiology, Meppel (Netherlands); Wagemakers, Harry P.A.; Koes, Bart W.; Bierma-Zeinstra, Sita M.A. [University Medical Center Rotterdam, Department of General Practice, Erasmus MC, Rotterdam (Netherlands)

    2010-05-15

    To evaluate meniscal status change on follow-up MRI after 1 year, prognostic factors and association with clinical outcome in patients with conservatively treated knee injury. We analysed 403 meniscal horns in 101 conservatively treated patients (59 male; mean age 40 years) in general practice who underwent initial knee MRI within 5 weeks of trauma. We performed ordinal logistic regression analysis to analyse prognostic factors for meniscal change on follow-up MRI after 1 year, and we assessed the association with clinical outcome. On follow-up MRI 49 meniscal horns had deteriorated and 18 had improved. Age (odds ratio [OR] 1.3/decade), body weight (OR 1.2/10 kg), total anterior cruciate ligament (ACL) rupture on initial MRI (OR 2.4), location in the posterior horn of the medial meniscus (OR 3.0) and an initial meniscal lesion (OR 0.3) were statistically significant predictors of meniscal MRI appearance change after 1 year, which was not associated with clinical outcome. In conservatively treated patients, meniscal deterioration on follow-up MRI 1 year after trauma is predicted by higher age and body weight, initial total ACL rupture, and location in the medial posterior horn. Change in MRI appearance is not associated with clinical outcome. (orig.)

  14. Meniscal configuration using magnetic resonance imaging; Configuracao meniscal pela ressonancia magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Arthur da Rocha C.; Turrini, Elisabete; Karoauk, Teresa C.C.; Lederman, Henrique M. [Escola Paulista de Medicina, Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem

    1997-04-01

    The authors present a review of the normal meniscal configuration and correlation with anatomic specimens. The images were obtained by magnetic resonance imaging. The images were obtained by magnetic resonance imaging. The authors emphasize the importance of knowing the relationship between the meniscus and the adjacent anatomic structures. (author) 31 refs., 10 figs., tabs.

  15. In vitro synthesis of tensioned synoviocyte bioscaffolds for meniscal fibrocartilage tissue engineering.

    Science.gov (United States)

    Warnock, Jennifer J; Baker, Lindsay; Ballard, George A; Ott, Jesse

    2013-12-03

    Meniscal injury is a common cause of lameness in the dog. Tissue engineered bioscaffolds may be a treatment option for meniscal incompetency, and ideally would possess meniscus- like extracellular matrix (ECM) and withstand meniscal tensile hoop strains. Synovium may be a useful cell source for meniscal tissue engineering because of its natural role in meniscal deficiency and its in vitro chondrogenic potential. The objective of this study is to compare meniscal -like extracellular matrix content of hyperconfluent synoviocyte cell sheets ("HCS") and hyperconfluent synoviocyte sheets which have been tensioned over wire hoops (tensioned synoviocyte bioscaffolds, "TSB") and cultured for 1 month. Long term culture with tension resulted in higher GAG concentration, higher chondrogenic index, higher collagen concentration, and type II collagen immunoreactivity in TSB versus HCS. Both HCS and TSB were immunoreactive for type I collagen, however, HCS had mild, patchy intracellular immunoreactivity while TSB had diffuse moderate immunoreactivity over the entire bisocaffold. The tissue architecture was markedly different between TSB and HCS, with TSB containing collagen organized in bands and sheets. Both HCS and TSB expressed alpha smooth muscle actin and displayed active contractile behavior. Double stranded DNA content was not different between TSB and HCS, while cell viability decreased in TSB. Long term culture of synoviocytes with tension improved meniscal- like extra cellular matrix components, specifically, the total collagen content, including type I and II collagen, and increased GAG content relative to HCS. Future research is warranted to investigate the potential of TSB for meniscal tissue engineering.

  16. Bucket Foundation Response Under Various Displacement Rates

    DEFF Research Database (Denmark)

    Vaitkunaite, Evelina; Nielsen, Benjaminn Nordahl; Ibsen, Lars Bo

    2016-01-01

    in a multi-bucket foundation system. The foundation model is at a scale of approximately 1:20 prototype foundation size. The tests are performed in a pressure tank with the foundation model installed in dense sand. Based on the data, the conclusion is that the bucket foundation design in a storm case should......The present testing program aims at showing the pore pressure response around a bucket foundation skirt as well as the load and displacement change due to ten different displacement rates. Research findings are useful for a numerical model calibration focusing on the design of the upwind foundation...

  17. Incidence and treatment of intra-articular lesions associated with anterior cruciate ligament tears.

    Science.gov (United States)

    Todor, Adrian; Nistor, Dan; Buescu, Cristian; Pojar, Adina; Lucaciu, Dan

    2014-01-01

    The aim of the study is to retrospectively review the patients admitted and treated in the "Alexandru Rădulescu" Orthopedics and Traumatology Clinic, Cluj-Napoca for an anterior cruciate ligament tear over a 2-year period and document the intra-articular lesions found at arthroscopy as well as the treatment used for these associated lesions. The case records of 88 patients operated for anterior cruciate ligament tear over a period of 2 years were reviewed. There were 67 males and 21 females with a mean age of 28.9 years, ranging from 14 to 49 years. After recording the patient demographics, we documented all the intra-articular lesions found during knee arthroscopy, as well as all procedures undertaken concomitant with the ACL reconstruction. 50 of the 88 patients (56.8%) had associated intra-articular lesions at the time of anterior cruciate ligament reconstruction. The most common injury found was a meniscus tear, 48 patients (54.5%) had a meniscal pathology at the time of ligament reconstruction, medial meniscus being the most frequent injured one, found in 37 patients. Meniscectomy and meniscus suture were the procedures performed for these lesions, meniscectomy being more frequent. Chondral defects were the next associated injuries found with an incidence of 15.9% of the cases. The medial side of the knee was the most common site of chondral pathology. ACL tears are frequently associated with other intra-articular lesions, especially medial meniscus tears and chondral defects affecting the medial compartment. Such pathology most often needs surgical attention during the anterior cruciate ligament reconstruction.

  18. Numerical simulation of cavitation flow characteristic on Pelton turbine bucket surface

    Science.gov (United States)

    Zeng, C. J.; Xiao, Y. X.; Zhu, W.; Yao, Y. Y.; Wang, Z. W.

    2015-01-01

    The internal flow in the rotating bucket of Pelton turbine is free water sheet flow with moving boundary. The runner operates under atmospheric and the cavitation in the bucket is still a controversial problem. While more and more field practice proved that there exists cavitation in the Pelton turbine bucket and the cavitation erosion may occur at the worst which will damage the bucket. So a well prediction about the cavitation flow on the bucket surface of Pelton turbine and the followed cavitation erosion characteristic can effectively guide the optimization of Pelton runner bucket and the stable operation of unit. This paper will investigate the appropriate numerical model and method for the unsteady 3D water-air-vapour multiphase cavitation flow which may occur on the Pelton bucket surface. The computational domain will include the nozzle pipe flow, semi-free surface jet and runner domain. Via comparing the numerical results of different turbulence, cavity and multiphase models, this paper will determine the suitable numerical model and method for the simulation of cavitation on the Pelton bucket surface. In order to investigate the conditions corresponding to the cavitation phenomena on the bucket surface, this paper will adopt the suitable model to simulate the various operational conditions of different water head and needle travel. Then, the characteristics of cavitation flow the development process of cavitation will be analysed in in great detail.

  19. Numerical simulation of cavitation flow characteristic on Pelton turbine bucket surface

    International Nuclear Information System (INIS)

    Zeng, C J; Xiao, Y X; Zhu, W; Yao, Y Y; Wang, Z W

    2015-01-01

    The internal flow in the rotating bucket of Pelton turbine is free water sheet flow with moving boundary. The runner operates under atmospheric and the cavitation in the bucket is still a controversial problem. While more and more field practice proved that there exists cavitation in the Pelton turbine bucket and the cavitation erosion may occur at the worst which will damage the bucket. So a well prediction about the cavitation flow on the bucket surface of Pelton turbine and the followed cavitation erosion characteristic can effectively guide the optimization of Pelton runner bucket and the stable operation of unit. This paper will investigate the appropriate numerical model and method for the unsteady 3D water-air-vapour multiphase cavitation flow which may occur on the Pelton bucket surface. The computational domain will include the nozzle pipe flow, semi-free surface jet and runner domain. Via comparing the numerical results of different turbulence, cavity and multiphase models, this paper will determine the suitable numerical model and method for the simulation of cavitation on the Pelton bucket surface. In order to investigate the conditions corresponding to the cavitation phenomena on the bucket surface, this paper will adopt the suitable model to simulate the various operational conditions of different water head and needle travel. Then, the characteristics of cavitation flow the development process of cavitation will be analysed in in great detail

  20. Thin-walled reinforcement lattice structure for hollow CMC buckets

    Science.gov (United States)

    de Diego, Peter

    2017-06-27

    A hollow ceramic matrix composite (CMC) turbine bucket with an internal reinforcement lattice structure has improved vibration properties and stiffness. The lattice structure is formed of thin-walled plies made of CMC. The wall structures are arranged and located according to high stress areas within the hollow bucket. After the melt infiltration process, the mandrels melt away, leaving the wall structure to become the internal lattice reinforcement structure of the bucket.

  1. A comparison of arthrography to clinical diagnostics for diagnosing meniscal lesions

    International Nuclear Information System (INIS)

    Neuer, H.

    1982-01-01

    A comparative investigation as to the exactness of clinical and arthrographical diagnostics was carried out on 176 patients who were clinically examined and operated on in the period of 1972-1980. Using solely clinical diagnostics, the total rate of exactness was 90,9%, the exactness regarding the internal meniscal lesion being significantly higher (94.2%) than that regarding external meniscal lesion (76.7%). Using solely arthrographic diagnostics, the total rate of exactness was 82%, the rate for internal meniscus being significantly lower (83.9%) than that obtained using clinical diagnostics. As for the external meniscus, the exactness of arthrography differs only slightly from clinical diagnostics with 74.7%. The most frequent sources of error in arthorgraphy were found to be lesions of the posterior horn at the internal meniscus. In cases of external meniscal lesions, especially when an internal meniscal lesion was existing at the same time, both examination methods failed in 5 cases. For routine diagnosing of meniscal lesions, arthrography is not necessary. An accurate clinical examination and anamnesis bring very good and exact results and should therefore be given absolute priority. (orig./MG) [de

  2. Intra-articular pathology associated with isolated posterior cruciate ligament injury on MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ringler, Michael D.; Collins, Mark S.; Howe, B.M. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Shotts, Ezekiel E. [NEA Baptist Clinic, Jonesboro, AR (United States)

    2016-12-15

    Unlike with anterior cruciate ligament injury, little is known about the prevalence of intra-articular pathology associated with isolated posterior cruciate ligament (PCL) injury in the knee. The objectives of this study were to characterize and identify the frequency of meniscal tears and osteochondral injuries in these patients, and to see if management might be affected. Altogether, 48 knee MRI exams with isolated PCL tears were evaluated for the presence of: grade and location of PCL tear, meniscal tear, articular chondral lesion, bone bruise, and fracture. Comparisons between PCL tear grade and location, as well as mechanism of injury when known, with the presence of various intra-articular pathologies, were made using the chi-square or Fisher's exact test as appropriate. In all, 69 % of isolated PCL tears occur in the midsubstance, 27 % proximally. Meniscal tears were seen in 25 % of knees, involving all segments of both menisci, except for the anterior horn medial meniscus. Altogether, 23 % had focal cartilage lesions, usually affecting the central third medial femoral condyle and medial trochlea, while 12.5 % of knees had fractures, and 48 % demonstrated bone bruises, usually involving the central to anterior tibiofemoral joint. The presence of a fracture (p = 0.0123) and proximal location of PCL tear (p = 0.0016) were both associated with the hyperextension mechanism of injury. There were no statistically significant associations between PCL tear grade and presence of intra-articular abnormality. Potentially treatable meniscal tears and osteochondral injuries are relatively prevalent, and demonstrable on MRI in patients with isolated acute PCL injury of the knee. (orig.)

  3. Unsteady CFD simulation for bucket design optimization of Pelton turbine runner

    Science.gov (United States)

    KUMASHIRO, Takashi; FUKUHARA, Haruki; TANI, Kiyohito

    2016-11-01

    To investigate flow patterns on the bucket of Pelton turbine runners is one of the important issues to improve the turbine performance. By studying the mechanism of loss generation on the flow around the bucket, it becomes possible to optimize the design of inner and outer bucket shape. For making it into study, computational fluid dynamics (CFD) is quite an effective method. It is normally used to simulate the flow in turbines and to expect the turbine performances in the development for many kind of water turbine including Pelton type. Especially in the bucket development, the numerical investigations are more useful than observations and measurements obtained in the model test to understand the transient flow patterns. In this paper, a numerical study on two different design buckets is introduced. The simplified analysis domain with consideration for reduction of computational load is also introduced. Furthermore the model tests of two buckets are also performed by using the same test equipment. As the results of the model test, a difference of turbine efficiency is clearly confirmed. The trend of calculated efficiencies on both buckets agrees with the experiment. To investigate the causes of that, the difference of unsteady flow patterns between two buckets is discussed based on the results of numerical analysis.

  4. A Retrospective Analysis of Concurrent Pathology in ACL-Reconstructed Knees of Elite Alpine Ski Racers

    DEFF Research Database (Denmark)

    Jordan, Matthew J; Doyle-Baker, Patricia; Heard, Mark

    2017-01-01

    /chondral surgery, 60% of meniscal tears and 80% of chondral lesions had worsened since the time of primary ACLR. CONCLUSION: Concurrent injury was common in this group of elite ski racers. Primary ACL tears were typically accompanied by lateral compartment chondral lesions and complex meniscal tears that worsened...... over time. ACL/MCL tears were the most common multiligament injury pattern.......BACKGROUND: Anterior cruciate ligament (ACL) tear is the most frequent injury in alpine ski racing, and there is a high prevalence of ACL reinjury. Limited data exist on the concurrent pathology with primary ACL tears in elite alpine ski racers and the magnitude of injury progression after primary...

  5. Undrained Response of Bucket Foundations to Moment Loading

    DEFF Research Database (Denmark)

    Barari, Amin; Ibsen, Lars Bo

    2012-01-01

    geotechnical engineers. This paper presents the experimental and numerical results of moment loading on small scale models of bucket foundations installed on Yoldia clay. The moment loading is experienced via the horizontal forces applied to features on a tower installed on bucket foundations. Different arm...

  6. Meniscofemoral ligaments: patterns of tears and pseudotears of the menisci using cadaveric and clinical material

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, Marcelo R. de [University of California San Diego, VA Health Care System, San Diego, CA (United States); Hospital Mae de Deus, Porto Alegre (Brazil); Universidade Federal Rio Grande do Sul, PPG Clinica Medica, Rio Grande do Sul (Brazil); Chung, Christine B.; Trudell, Debbra; Resnick, Donald [University of California San Diego, VA Health Care System, San Diego, CA (United States)

    2007-08-15

    The purpose of the study was to determine the different types of pseudotears of the posterior horn of the lateral meniscus caused by the nearby meniscofemoral ligaments (MFLs), and to correlate the presence of these ligaments with patterns of meniscal tear. Retrospective clinical study with patients and prospective observatory study with cadaveric material. Magnetic resonance imaging studies of the knee in 49 patients who had subsequent arthroscopy of the knee performed over a 1-year period at a single institution were reviewed by two readers in consensus for the presence and morphology of the MFLs of Humphry (LH) and Wrisberg (LW). Ten cadaveric knee specimens were used for MRI, anatomic, and histologic study. The LH was present in 55% of patients, the LW in 94%, and both were present in 44.9%. The thickness of the LH and LW ranged from 1-3 mm (mean 1.9, SD 0.61), and from 1-3.8 mm (mean 1.8, SD 0.65) respectively (p > 0.05). A pseudotear in the posterior horn of the lateral meniscus was present in 63% of patients. In 13% the pseudotear was vertically oriented, and in 87% the pseudotear had an anterosuperior to posteroinferior orientation, ranging from 37 to 87 . There was no association between the presence of one or both MFLs and the occurrence of medial or lateral meniscal tears (p > 0.05). Meniscofemoral ligaments are frequent anatomical structures that are found in the majority of knees with MRI. They commonly cause a pseudotear of the posterior horn of the lateral meniscus that can be simple, double, or complex in appearance, with vertical or anterosuperior to posteroinferior orientation. (orig.)

  7. Is intra-articular pathology associated with MCL edema on MR imaging of the non-traumatic knee?

    International Nuclear Information System (INIS)

    Blankenbaker, Donna G.; De Smet, Arthur A.; Fine, Jason P.

    2005-01-01

    Edema surrounding the medial collateral ligament (MCL) is seen on MR imaging in patients with MCL injuries and in patients with radiographic osteoarthritis in the non-traumatic knee. Because we noted MCL edema in patients without prior trauma or osteoarthritis, we studied the association between intra-articular pathology and MCL edema in patients without knee trauma. We evaluated the MR examinations of 247 consecutive patients (121 male, 126 female with a mean age of 44 years) without recent trauma for the presence of edema surrounding the MCL, meniscal and ACL tears, medial meniscal extrusion, medial compartment chondromalacia, and osteoarthritis. The percentages of patients illustrating MCL edema with and without each type of pathology were compared using Fisher's exact test to determine if there was a statistically significant association. We found MCL edema in 60% of 247 patients. MCL edema was present in 67% of patients with medial meniscal tears, 35% with lateral meniscal tears, 100% with meniscal extrusion of 3 mm or more, 78% with femoral chondromalacia, 82% with tibial chondromalacia, and 50% with osteoarthritis. The percentage of patients with edema increased with the severity of the chondromalacia. These associations were all statistically significant (p <0.02). The mean age of those with MCL edema was 49.7 years compared with 34.9 years without MCL edema (p <0.001). Patient gender and ACL tear did not correlate with MCL edema. Nine (4%) of the 247 patients had MCL edema without intra-articular pathology. None of these 9 patients had MCL tenderness or joint laxity on physical examination. We confirmed that MCL edema is associated with osteoarthritis, but is also associated with meniscal tears, meniscal extrusion, and chondromalacia. In addition, MCL edema can be seen in patients without intra-articular pathology, recent trauma or MCL abnormality on physical examination. (orig.)

  8. Is intra-articular pathology associated with MCL edema on MR imaging of the non-traumatic knee?

    Energy Technology Data Exchange (ETDEWEB)

    Blankenbaker, Donna G.; De Smet, Arthur A. [University of Wisconsin Medical School, Division of Musculoskeletal Imaging, Department of Radiology, Madison (United States); Fine, Jason P. [University of Wisconsin, Department of Statistics, Madison (United States); University of Wisconsin, Department of Biostatistics and Informatics, Madison (United States)

    2005-08-01

    Edema surrounding the medial collateral ligament (MCL) is seen on MR imaging in patients with MCL injuries and in patients with radiographic osteoarthritis in the non-traumatic knee. Because we noted MCL edema in patients without prior trauma or osteoarthritis, we studied the association between intra-articular pathology and MCL edema in patients without knee trauma. We evaluated the MR examinations of 247 consecutive patients (121 male, 126 female with a mean age of 44 years) without recent trauma for the presence of edema surrounding the MCL, meniscal and ACL tears, medial meniscal extrusion, medial compartment chondromalacia, and osteoarthritis. The percentages of patients illustrating MCL edema with and without each type of pathology were compared using Fisher's exact test to determine if there was a statistically significant association. We found MCL edema in 60% of 247 patients. MCL edema was present in 67% of patients with medial meniscal tears, 35% with lateral meniscal tears, 100% with meniscal extrusion of 3 mm or more, 78% with femoral chondromalacia, 82% with tibial chondromalacia, and 50% with osteoarthritis. The percentage of patients with edema increased with the severity of the chondromalacia. These associations were all statistically significant (p <0.02). The mean age of those with MCL edema was 49.7 years compared with 34.9 years without MCL edema (p <0.001). Patient gender and ACL tear did not correlate with MCL edema. Nine (4%) of the 247 patients had MCL edema without intra-articular pathology. None of these 9 patients had MCL tenderness or joint laxity on physical examination. We confirmed that MCL edema is associated with osteoarthritis, but is also associated with meniscal tears, meniscal extrusion, and chondromalacia. In addition, MCL edema can be seen in patients without intra-articular pathology, recent trauma or MCL abnormality on physical examination. (orig.)

  9. Barrier bucket experiment at the AGS

    Directory of Open Access Journals (Sweden)

    M. Fujieda

    1999-12-01

    Full Text Available A barrier bucket experiment with two dedicated barrier cavities was performed at the Brookhaven AGS. One of the barrier cavities was a magnetic alloy (MA–loaded cavity and the other was a ferrite-loaded cavity. They generated a single sine wave with a peak voltage of 40 kV at a repetition rate of 351 kHz. A barrier rf system was established with these cavities and five bunches from the AGS booster were accumulated. A total of 3×10^{13} protons were stored without beam loss, and were successfully rebunched and accelerated. The longitudinal emittance growth was observed during accumulation by the barrier bucket, the blowup factor of which was about 3. The longitudinal mismatch between the rf bucket and the beam bunch was the main reason for the emittance growth. The potential distortions by beam loading of the ferrite cavity and the overshooting voltage of the MA cavity disturbed the smooth debunching.

  10. Ultrasound-guided percutaneous drainage of meniscal cysts: preliminary clinical experience

    International Nuclear Information System (INIS)

    MacMahon, P.J.; Brennan, D.D.; Duke, D.; Forde, S.; Eustace, S.J.

    2007-01-01

    Aim: To evaluate the efficacy of ultrasound-guided percutaneous drainage of symptomatic meniscal cysts. Materials and methods: Patients with lateral knee joint tenderness and swelling and confirmed meniscal cyst on magnetic resonance imaging (MRI) were consecutively enrolled for ultrasound-guided percutaneous cyst aspiration. Cysts were injected with local anaesthetic and steroid before completion of procedure. All 18 patients (all male, average age 33 years) were subsequently followed up (average time 10 months) and meniscal cyst symptoms assessed by questionnaire. Fischer's exact test used to analyse the data. Results: In every case the procedure was well tolerated, and each patient indicated that they would be willing to have a repeat procedure in the future. Ten patients reported complete resolution of symptoms secondary to therapeutic cyst aspiration and had resumed participation in high-performance sport. Two patients reported a satisfactory sustained response, reporting only occasional 'twinges of pain'. In the remaining six patients, symptoms returned after an initial pain-free period. The pain-free period ranged from 1-8 weeks. In this study, patient outcome did not significantly correlate with any meniscal cyst characteristic. Conclusion: Ultrasound-guided percutaneous aspiration of meniscal cysts is a well-tolerated, simple, and safe procedure. In this small patient series, it was associated with positive early results with favourable outcomes in the mid to long-term. It should be considered in patients unsuitable for surgical debridement or as an interim therapy if surgery is delayed or postponed

  11. MRI versus ultrasonography to assess meniscal abnormalities in acute knees.

    Science.gov (United States)

    Cook, James L; Cook, Cristi R; Stannard, James P; Vaughn, Gavin; Wilson, Nichole; Roller, Brandon L; Stoker, Aaron M; Jayabalan, Prakash; Hdeib, Moses; Kuroki, Keiichi

    2014-08-01

    While magnetic resonance imaging (MRI) is often considered the "gold standard" diagnostic imaging modality for detection of meniscal abnormalities, it is associated with misdiagnosis in as high as 47% of cases, is costly, and is not readily available to a large number of patients. Ultrasonographic examination of the knee has been reported to be an effective diagnostic tool for this purpose with the potential to overcome many of the shortcomings of MRI. The purpose of this study is to determine the clinical usefulness of ultrasonography for diagnosis of meniscal pathology in patients with acute knee pain and compare its diagnostic accuracy to MRI in a clinical setting. With Institutional Review Board approval, patients (n = 71) with acute knee pain were prospectively enrolled with informed consent. Preoperative MRI (1.5 T) was performed on each affected knee using the hospital's standard equipment and protocols and read by faculty radiologists trained in musculoskeletal MRI. Ultrasonographic assessments of each affected knee were performed by one of two faculty members trained in musculoskeletal ultrasonography using a 10 to 14 MHz linear transducer. Arthroscopic evaluation of affected knees was performed by one of three faculty orthopedic surgeons to assess and record all joint pathology, which served as the reference standard for determining presence, type, and severity of meniscal pathology. All evaluators for each diagnostic modality were blinded to all other data. Data were collected and compared by a separate investigator to determine sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), correct classification rate (CCR), likelihood ratios (LR[+] and LR[-]), and odds ratios. Preoperative ultrasonographic assessment of meniscal pathology was associated with Sn = 91.2%, Sp = 84.2%, PPV = 94.5%, NPV = 76.2%, CCR = 89.5%, LR(+) = 5.78, and LR(-) = 0.10. Preoperative MRI assessment of

  12. Ghost imaging with bucket detection and point detection

    Science.gov (United States)

    Zhang, De-Jian; Yin, Rao; Wang, Tong-Biao; Liao, Qing-Hua; Li, Hong-Guo; Liao, Qinghong; Liu, Jiang-Tao

    2018-04-01

    We experimentally investigate ghost imaging with bucket detection and point detection in which three types of illuminating sources are applied: (a) pseudo-thermal light source; (b) amplitude modulated true thermal light source; (c) amplitude modulated laser source. Experimental results show that the quality of ghost images reconstructed with true thermal light or laser beam is insensitive to the usage of bucket or point detector, however, the quality of ghost images reconstructed with pseudo-thermal light in bucket detector case is better than that in point detector case. Our theoretical analysis shows that the reason for this is due to the first order transverse coherence of the illuminating source.

  13. Bucket elevator type continuous unloader; Basket elevator gata renzokushiki anroda

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-04-20

    This unloader was delivered to Wakayama branch of Sumikin Butsuryu in the site of Wakayama steel plant of Sumitomo Metal Industries Ltd. for landing sub-materials for ironworks. Main specifications: (1) Capacity: 400t/h for limestone, 280t/h for gypsum, (2) Kinds of ships: 5,000DWT maximum, (3) Boom swing radius: 20m. Features: (1) Simple light-weight unloader for not large ships for main materials but small coastal service ships which works with not swing motion but only traveling and normal-directional motion of the under structure of a bucket elevator unit, (2) Various useful functions such as ground conveyance, truck loading, back yard stacking and back yard shipment for handling of various sub-materials. (translated by NEDO)

  14. Is radiographic measurement of bony landmarks reliable for lateral meniscal sizing?

    Science.gov (United States)

    Yoon, Jung-Ro; Kim, Taik-Seon; Lim, Hong-Chul; Lim, Hyung-Tae; Yang, Jae-Hyuk

    2011-03-01

    The accuracy of meniscal measurement methods is still in debate. The authors' protocol for radiologic measurements will provide reproducible bony landmarks, and this measurement method of the lateral tibial plateau will correlate with the actual anatomic value. Controlled laboratory study. Twenty-five samples of fresh lateral meniscus with attached proximal tibia were obtained during total knee arthroplasty. Each sample was obtained without damage to the meniscus and bony attachment sites. The inclusion criterion was mild to moderate osteoarthritis in patients with mechanical axis deviation of less than 15°. Knees with lateral compartment osteoarthritic change or injured or degenerated menisci were excluded. For the lateral tibial plateau length measurements, the radiographic beam was angled 10° caudally at neutral rotation, which allowed differentiation of the lateral plateau cortical margins from the medial plateau. The transition points were identified and used for length measurement. The values of length were then compared with the conventional Pollard method and the anatomic values. The width measurement was done according to Pollard's protocol. For each knee, the percentage deviation from the anatomic dimension was recorded. Intraobserver error and interobserver error were calculated. The deviation of the authors' radiographic length measurements from anatomic dimensions was 1.4 ± 1.1 mm. The deviation of Pollard's radiographic length measurements was 4.1 ± 2.0 mm. With respect to accuracy-which represents the frequency of measurements that fall within 10% of measurements-the accuracy of authors' length was 98%, whereas for Pollard's method it was 40%. There was a good correlation between anatomic meniscal dimensions and each radiologic plateau dimensions for lateral meniscal width (R(2) = .790) and the authors' lateral meniscal length (R(2) = .823) and fair correlation for Pollard's lateral meniscal length (R(2) = .660). The reliability of each

  15. Sonographic Imaging of Meniscal Subluxation in Patients with Radiographic Knee Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Chun-Hung Ko

    2007-09-01

    Conclusion: Meniscal subluxation is a prominent feature on weight-bearing sonographic imaging in patients with radiographic osteoarthritis and could be considered as a risk factor for the development of knee osteoarthritis. By using musculoskeletal ultrasonography, one can detect this occult meniscal derangement early before the appearance of radiographic signs of osteoarthritis.

  16. Second Stage Turbine Bucket Airfoil.

    Science.gov (United States)

    Xu, Liming; Ahmadi, Majid; Humanchuk, David John; Moretto, Nicholas; Delehanty, Richard Edward

    2003-05-06

    The second-stage buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in inches in Table I wherein Z is a perpendicular distance from a plane normal to a radius of the turbine centerline and containing the X and Y values with the Z value commencing at zero in the X, Y plane at the radially innermost aerodynamic section of the airfoil and X and Y are coordinate values defining the airfoil profile at each distance Z. The X, Y and Z values may be scaled as a function of the same constant or number to provide a scaled-up or scaled-down airfoil section for the bucket.

  17. Third-stage turbine bucket airfoil

    Science.gov (United States)

    Pirolla, Peter Paul; Siden, Gunnar Leif; Humanchuk, David John; Brassfield, Steven Robert; Wilson, Paul Stuart

    2002-01-01

    The third-stage buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in inches in Table I wherein Z is a perpendicular distance from a plane normal to a radius of the turbine centerline and containing the X and Y values with the Z value commencing at zero in the X, Y plane at the radially innermost aerodynamic section of the airfoil and X and Y are coordinates defining the airfoil profile at each distance Z. The X, Y and Z values may be scaled as a function of the same constant or number to provide a scaled-up or scaled-down airfoil section for the bucket.

  18. Tear film measurement by optical reflectometry technique

    Science.gov (United States)

    Lu, Hui; Wang, Michael R.; Wang, Jianhua; Shen, Meixiao

    2014-01-01

    Abstract. Evaluation of tear film is performed by an optical reflectometer system with alignment guided by a galvanometer scanner. The reflectometer system utilizes optical fibers to deliver illumination light to the tear film and collect the film reflectance as a function of wavelength. Film thickness is determined by best fitting the reflectance-wavelength curve. The spectral reflectance acquisition time is 15 ms, fast enough for detecting film thickness changes. Fast beam alignment of 1 s is achieved by the galvanometer scanner. The reflectometer was first used to evaluate artificial tear film on a model eye with and without a contact lens. The film thickness and thinning rate have been successfully quantified with the minimum measured thickness of about 0.3 μm. Tear films in human eyes, with and without a contact lens, have also been evaluated. A high-contrast spectral reflectance signal from the precontact lens tear film is clearly observed, and the thinning dynamics have been easily recorded from 3.69 to 1.31 μm with lipid layer thickness variation in the range of 41 to 67 nm. The accuracy of the measurement is better than ±0.58% of the film thickness at an estimated tear film refractive index error of ±0.001. The fiber-based reflectometer system is compact and easy to handle. PMID:24500519

  19. Buckling of Bucket Foundations

    DEFF Research Database (Denmark)

    Madsen, Søren; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    2012-01-01

    In this paper, the risk of structural buckling during installation of large-diameter bucket foundations is addressed using numerical methods. Imperfect geometries are introduced based on the pre-buckling mode shapes from a linear Eigenvalue buckling analysis. Various imperfect geometries are intr...

  20. MRI follow-up of conservatively treated meniscal knee lesions in general practice

    NARCIS (Netherlands)

    E.H.G. Oei (Edwin); I.M. Koster (Ingrid); J.H.J. Hensen; S.S. Boks (Simone); H.P.A. Wagemakers (Harry); B.W. Koes (Bart); D. Vroegindeweij (Dammis); S.M. Bierma-Zeinstra (Sita); M.G.M. Hunink (Myriam)

    2010-01-01

    textabstractObjective: To evaluate meniscal status change on follow-up MRI after 1 year, prognostic factors and association with clinical outcome in patients with conservatively treated knee injury. Methods: We analysed 403 meniscal horns in 101 conservatively treated patients (59 male; mean age 40

  1. Cell Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath

    Science.gov (United States)

    2017-07-01

    to subsequently guide tissue regeneration , for example, by seeded tissue progenitor cells . To achieve this objective, the first step is to develop...AWARD NUMBER: W81XWH-15-1-0104 TITLE: Cell -Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath PRINCIPAL INVESTIGATOR...SUBTITLE 5a. CONTRACT NUMBER Cell -Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath 5b. GRANT NUMBER W81XWH-15-1-0104 5c. PROGRAM

  2. Review: Modelling of meniscus of knee joint during soccer kicking

    Science.gov (United States)

    Azrul Hisham Mohd Adib, Mohd; Firdaus Jaafar, Mohd

    2013-12-01

    Knee is a part of the body that located between thigh and shank is one of the most complicated and largest joints in the human body. The common injuries that occur are ligaments, meniscus or bone fracture. During soccer games, the knee is the most critical part that will easily injure due to the shock from an external impact. Torn meniscus is one of the effects. This study will investigate the effect towards the meniscus within the knee joint during soccer ball kicking. We conduct a literary review of 14 journals that discuss the general view of meniscus and also soccer kicking. The selected topics for this review paper are meniscal function, meniscal movement, meniscal tears and also instep kick. As a finding, statistics show that most meniscal tears (73%) occurred in athletes who were soccer players, basketball players or skiers. The tear is frequently happening at the medial side rather than lateral side with a percentage of 70%.

  3. Microwave instability in α-like quasi-isochronous buckets

    International Nuclear Information System (INIS)

    Ng, K.Y.

    1996-10-01

    The problem of microwave instability inside an α-like quasi- isochronous bucket is addressed. The coupling impedance at wavelengths shorter than the length of the short bunches is found to be not small. The Keil-Schnell criterion is modified for such a bucket using the concept of self-bunching. The mechanism of particle loss during a microwave growth is examined

  4. Accuracy of 3-Tesla MR and MR arthrography in diagnosis of meniscal retear in the post-operative knee

    Energy Technology Data Exchange (ETDEWEB)

    Magee, Thomas [NSI, Merritt Island, FL (United States); University of Central Florida School of Medicine, Orlando, FL (United States)

    2014-08-15

    This study assesses the accuracy of 3-Tesla (3-T) conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography in the diagnosis of meniscal retears as compared with arthroscopy. The study also assess whether there are false-negative cases in which injected contrast does not extend into the meniscus despite a meniscal retear being seen on arthroscopy. One hundred consecutive knee MR arthrograms performed on patients with previous knee surgery were reviewed retrospectively. 3-T conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography were assessed for meniscal retears as compared with arthroscopy. The criterion used to diagnose a meniscal retear on MR arthrogram was injected contrast tracking into the meniscus. All patients underwent second-look arthroscopy. Seventy-four patients had conventional MR findings consistent with a meniscal retear. In 83 of the 100 patients, intraarticular contrast helped in demonstrating a retear. In ten patients, there were MR findings consistent with a meniscal retear despite intra-articular contrast not tracking into the meniscus. Ninety-four of the 100 patients had meniscal retears on second-look arthroscopy. Three-Tesla conventional MR examination was 78 % sensitive and 75 % specific, MR arthrogram examination was 88 % sensitive and 100 % specific, and the combined use of MR and MR arthrogram imaging was 98 % sensitive and 75 % specific in the diagnosis of a meniscal retear. The combined use of 3-T MR and MR arthrography allows for high sensitivity and specificity in meniscal retear detection. In some patients, intraarticular contrast will not track into a meniscal retear. When MR findings are consistent with a meniscal retear but contrast does not extend into the meniscus, a meniscal retear is likely. (orig.)

  5. MR imaging of posterior cruciate ligament injuries

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Nobuyuki [Tsukuba Univ., Ibaraki (Japan). Hospital; Niitsu, Mamoru; Itai, Yuji; Sato, Motohiro; Kujiraoka, Yuka; Ikeda, Kotaro; Kanamori, Akihiro

    2001-07-01

    Posterior cruciate ligament (PCL) injuries are less frequent than anterior cruciate ligament (ACL) injuries, but are presumably more common than once thought. Thirty-nine patients with PCL injuries identified on MR images were studied. The criteria for PCL injury were complete tear, partial tear, and avulsion fracture. The approximate site of a partial tear was categorized as proximal, midsubstance, distal, or combination. Fourteen patients (35.9%) had complete tears of the PCL, 21 patients (53.8%) had partial tears, and four patients (10.3%) had avulsion fractures. A total of 12 patients (30.7%) had isolated PCL injuries, while the remaining 27 patients demonstrated evidence of other coexistent knee injuries, such as meniscal tears and ligamentous injuries. Of coexistent knee injuries, meniscal tears (18 patients, 46.2%) were most often seen. (author)

  6. MR imaging of posterior cruciate ligament injuries

    International Nuclear Information System (INIS)

    Takahashi, Nobuyuki; Niitsu, Mamoru; Itai, Yuji; Sato, Motohiro; Kujiraoka, Yuka; Ikeda, Kotaro; Kanamori, Akihiro

    2001-01-01

    Posterior cruciate ligament (PCL) injuries are less frequent than anterior cruciate ligament (ACL) injuries, but are presumably more common than once thought. Thirty-nine patients with PCL injuries identified on MR images were studied. The criteria for PCL injury were complete tear, partial tear, and avulsion fracture. The approximate site of a partial tear was categorized as proximal, midsubstance, distal, or combination. Fourteen patients (35.9%) had complete tears of the PCL, 21 patients (53.8%) had partial tears, and four patients (10.3%) had avulsion fractures. A total of 12 patients (30.7%) had isolated PCL injuries, while the remaining 27 patients demonstrated evidence of other coexistent knee injuries, such as meniscal tears and ligamentous injuries. Of coexistent knee injuries, meniscal tears (18 patients, 46.2%) were most often seen. (author)

  7. Set-up and Test Procedure for Suction Installation and Uninstallation of Bucket Foundation

    DEFF Research Database (Denmark)

    Koteras, Aleksandra Katarzyna

    This technical report describes the set-up and the test procedures for installation and uninstallation of medium-scale model of bucket foundation that can be performed in the geotechnical part of laboratory in Aalborg University. The installation of bucket foundation can be tested with the use of......) and loading frame used for those tests have been already used for axially static and cyclic loading of piles (Thomassen, 2015a) and for axially static and cyclic loading of bucket foundation (Vaitkunaite et al., 2015).......This technical report describes the set-up and the test procedures for installation and uninstallation of medium-scale model of bucket foundation that can be performed in the geotechnical part of laboratory in Aalborg University. The installation of bucket foundation can be tested with the use...... of suction under the bucket lid or by applying additional force through the hydraulic piston, forcing the bucket to penetrate into the soil. Tests for uninstallation are performed also with the use of water pressure, as a reverse process to the suction installation. Both installation and uninstallation tests...

  8. Symptomatic knee disorders in floor layers and graphic designers. A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Jensen Lilli

    2012-09-01

    Full Text Available Abstract Background Previous studies have described an increased risk of developing tibio-femoral osteoarthritis (TF OA, meniscal tears and bursitis among those with a trade as floor layers. The purpose of this study was to analyse symptomatic knee disorders among floor layers that were highly exposed to kneeling work tasks compared to graphic designers without knee-demanding work tasks. Methods Data on the Knee injury and Osteoarthritis Outcome Score (KOOS were collected by questionnaires. In total 134 floor layers and 120 graphic designers had a bilateral radiographic knee examination to detect TF OA and patella-femoral (PF OA. A random sample of 92 floor layers and 49 graphic designers had Magnetic Resonance Imaging (MRI of both knees to examine meniscal tears. Means of the subscales of KOOS were compared by analysis of variance. The risk ratio of symptomatic knee disorders defined as a combination of radiological detected knee OA or MRI-detected meniscal tears combined with a low KOOS score was estimated by logistic regression in floor layers with 95% confidence interval (CI and adjusted for age, body mass index, traumas, and knee-straining sports activities. Symptomatic knee OA or meniscal tears were defined as a combination of low KOOS-scores and radiographic or MRI pathology. Results Symptomatic TF and medial meniscal tears were found in floor layers compared to graphic designers with odds ratios 2.6 (95%CI 0.99-6.9 and 2.04 (95% CI 0.77-5.5, respectively. There were no differences in PF OA. Floor layers scored significantly lower on all KOOS subscales compared to graphic designers. Significantly lower scores on the KOOS subscales were also found for radiographic TF and PF OA regardless of trade but not for meniscal tears. Conclusions The study showed an overall increased risk of developing symptomatic TF OA in a group of floor layers with a substantial amount of kneeling work positions. Prevention would be appropriate to reduce the

  9. Characteristic Behavior of Bucket Foundations

    DEFF Research Database (Denmark)

    Barari, Amin

    political and industrial forces(particularly in northern Europe) supporting the development of the offshore wind industry. The overall aim of the research presented in this thesis was to improve the design of offshore wind turbine foundations. The work was divided into two main researchefforts: geotechnical...... reduce the risks and costsrelated to offshore geotechnics. The thesis examines: 1.Characteristic Behavior of Bucket Foundations 2. Modeling of Water Flow through Porous Media The outcomes of each of the research contributions are summarized in four research articles, either directly or indirectly...... engineering experiments to gain insight into the behavior of offshore bucket foundations, and development of methods to improve the study of infiltration intounsaturated soils, an important problem in geo-environmental engineering. The outcomes of the research have the potential to directly or indirectly...

  10. Effect of Embedment on the Vertical Bearing Capacity of Bucket Foundations in Clay

    DEFF Research Database (Denmark)

    Barari, Amin; Ibsen, Lars Bo

    2011-01-01

    To evaluate the undrained behaviour of bucket foundations installed on Yoldia clay, 100 tests on bucket foundations subject to vertical and moment loadings were conducted at Aalborg university geotechnical centre. Bucket foundations are tubular steel foundations that are installed by sealing...

  11. Seepage Study for Suction Installation of Bucket Foundation in Different Soil Combinations

    DEFF Research Database (Denmark)

    Koteras, Aleksandra Katarzyna; Ibsen, Lars Bo; Clausen, Johan Christian

    2016-01-01

    Research has proven the bucket foundation to be a feasible and an attractive solution for offshore wind turbines. Its potential derives partly from the cost-effectiveness due to the suction-assisted installation. The suction applied under the bucket lid produces a downward driving force and addit......Research has proven the bucket foundation to be a feasible and an attractive solution for offshore wind turbines. Its potential derives partly from the cost-effectiveness due to the suction-assisted installation. The suction applied under the bucket lid produces a downward driving force...... around the bucket skirt. The exceedance of critical suction might lead to installation failure due to formation of piping channels, which break the hydraulic seal between the skirt and soil. The excess pore pressure arising due to applied suction changes the effective stress, hence the penetration...

  12. Cartilage Degeneration, Subchondral Mineral and Meniscal Mineral Densities in Hartley and Strain 13 Guinea Pigs

    Science.gov (United States)

    Sun, Yubo; Scannell, Brian P; Honeycutt, Patrick R; Mauerhan, David R; H, James Norton; Hanley Jr, Edward N

    2015-01-01

    Osteoarthritis is a joint disease involved in articular cartilage, subchondral bone, meniscus and synovial membrane. This study sought to examine cartilage degeneration, subchondral bone mineral density (BMD) and meniscal mineral density (MD) in male Hartley, female Hartley and female strain 13 guinea pigs to determine the association of cartilage degeneration with subchondral BMD and meniscal MD. Cartilage degeneration, subchondral BMD and meniscal MD in 12 months old guinea pigs were examined with histochemistry, X-ray densitometry and calcium analysis. We found that male Hartley guinea pigs had more severe cartilage degeneration, subchondral BMD and meniscal MD than female Hartley guinea pigs, but not female strain 13 guinea pigs. Female strain 13 guinea pigs had more severe cartilage degeneration and higher subchondral BMD, but not meniscal MD, than female Hartley guinea pigs. These findings indicate that higher subchondral BMD, not meniscal MD, is associated with more severe cartilage degeneration in the guinea pigs and suggest that abnormal subchondral BMD may be a therapeutic target for OA treatment. These findings also indicate that the pathogenesis of OA in the male guinea pigs and female guinea pigs are different. Female strain 13 guinea pig may be used to study female gender-specific pathogenesis of OA. PMID:26401159

  13. Meniscal transplantation: procedures, outcomes, and rehabilitation

    Directory of Open Access Journals (Sweden)

    Young J

    2017-05-01

    Full Text Available James Young, Francois Tudor, Ahmed Mahmoud, Peter Myers Brisbane Orthopaedic & Sports Medicine Centre, Brisbane Private Hospital, Spring Hill, Brisbane, Queensland, Australia Abstract: Meniscal allograft transplantation (MAT is a possible treatment option for patients with joint pain after meniscectomy. It is necessary that the joint be aligned and stable. Current evidence shows that MAT improves pain and mechanical function in the mid to long term with patients reporting significantly improved outcomes at up to 15 years following surgery. Studies on survivorship showed up to 76% graft survival at 10 years. Recent studies have suggested a chondroprotective effect, but there is, at present, no evidence to support MAT in the prevention of osteoarthritis. This review article reported the current evidence for MAT showing support for fresh frozen, nonirradiated allografts. However, further research is required to determine the ideal indications for MAT, the optimal graft fixation method, and the safest rehabilitation protocol. Keywords: meniscus, meniscectomy, meniscal allograft transplantation

  14. Shelbourne's update of the O'Donoghue knee triad in a 17-year-old male Rugby player.

    Science.gov (United States)

    Dacombe, Peter Jonathan

    2013-01-23

    Acute athletic knee injuries are often caused by a combination of valgus impact with external rotation of the tibia leading to a triad of injuries involving medial collateral and anterior cruciate ligament disruption with associated meniscal damage. This injury pattern has been greatly discussed in the literature with conflicts of opinion and evidence as to whether medial or lateral meniscal pathology has a higher incidence. This case report introduces a 17-year-old male athlete with this unhappy triad It will evaluate the clinical assessment which suggested a medial meniscal lesion follow the patient through arthroscopy revealing a lateral meniscal tear in addition to complete anterior cruciate ligament rupture and grade 2 medial collateral ligament tear. It will go on to look at the evidence base for the relative incidence of lateral and medial meniscal injuries and will evaluate the role of MRI in assessing acute athletic knee injuries.

  15. Development of a fast curing tissue adhesive for meniscus tear repair.

    Science.gov (United States)

    Bochyńska, Agnieszka Izabela; Hannink, Gerjon; Janssen, Dennis; Buma, Pieter; Grijpma, Dirk W

    2017-01-01

    Isocyanate-terminated adhesive amphiphilic block copolymers are attractive materials to treat meniscus tears due to their tuneable mechanical properties and good adhesive characteristics. However, a drawback of this class of materials is their relatively long curing time. In this study, we evaluate the use of an amine cross-linker and addition of catalysts as two strategies to accelerate the curing rates of a recently developed biodegradable reactive isocyanate-terminated hyper-branched adhesive block copolymer prepared from polyethylene glycol (PEG), trimethylene carbonate, citric acid and hexamethylene diisocyanate. The curing kinetics of the hyper-branched adhesive alone and in combination with different concentrations of spermidine solutions, and after addition of 2,2-dimorpholinodiethylether (DMDEE) or 1,4-diazabicyclo [2.2.2] octane (DABCO) were determined using FTIR. Additionally, lap-shear adhesion tests using all compositions at various time points were performed. The two most promising compositions of the fast curing adhesives were evaluated in a meniscus bucket handle lesion model and their performance was compared with that of fibrin glue. The results showed that addition of both spermidine and catalysts to the adhesive copolymer can accelerate the curing rate and that firm adhesion can already be achieved after 2 h. The adhesive strength to meniscus tissue of 3.2-3.7 N was considerably higher for the newly developed compositions than for fibrin glue (0.3 N). The proposed combination of an adhesive component and a cross-linking component or catalyst is a promising way to accelerate curing rates of isocyanate-terminated tissue adhesives.

  16. MRI EVALUATION OF PAINFUL KNEE JOINT- THE CORRELATION OF MULTIPLE COEXISTING PATHOLOGIES, AGE AND SEX

    Directory of Open Access Journals (Sweden)

    Mukheswar Pame

    2017-03-01

    Full Text Available BACKGROUND 1. To evaluate the incidence and coexistence of multiple knee joint pathologies causing painful knee and their correlation to age and sex. 2. To evaluate the Magnetic Resonance Imaging (MRI features in various knee pathologies and to identify the common lesions. MATERIALS AND METHODS A retrospective study was performed using the clinical data of patients presenting with painful knee joint which were evaluated with MRI. Data from 200 patients examined between September 2015 and August 2016 were included into this study. The data was analysed statistically to evaluate the correlation between the MR pathological findings to age and sex of the patients. RESULTS The patient’s age ranged between 8 and 75 years (mean: 36 years. Anterior cruciate ligament (ACL tear was the commonest finding (60% followed by bursitis (55%, meniscal degeneration (54.6% and meniscal tear (52%. Primary signs of ACL tear were hyperintensity, discontinuity and nonvisualisation. Secondary signs like Posterior cruciate ligament (PCL buckling, PCL index of greater than 0.5, uncovered Lateral meniscus (LM and bone contusion assisted in diagnosis in indeterminate cases. Mid substance was the commonest site of ACL tear (64%. PCL tear accounted for only a small percentage (7%. Medial Meniscus (MM tear (35% was commoner than LM tear (17%. The posterior horn of meniscus was the commonest site of injury (86.5%. Age was significantly correlated with meniscal degeneration and tear, Medial collateral ligament (MCL degeneration, parameniscal cyst, and chondromalacia patellae. A significant correlation between male gender and ACL injury was noted. Meniscal injury was significantly correlated with bursitis, as well with MCL injury. Bone bruise was significantly correlated with ACL injury, MCL injury and Lateral collateral ligament (LCL injury. CONCLUSIONS MRI findings of certain pathologies in a painful knee can coexist and significantly correlate with each other, age and sex of

  17. Numerical and Experimental Investigations of the Flow in a Stationary Pelton Bucket

    Science.gov (United States)

    Nakanishi, Yuji; Fujii, Tsuneaki; Kawaguchi, Sho

    A numerical code based on one of mesh-free particle methods, a Moving-Particle Semi-implicit (MPS) Method has been used for the simulation of free surface flows in a bucket of Pelton turbines so far. In this study, the flow in a stationary bucket is investigated by MPS simulation and experiment to validate the numerical code. The free surface flow dependent on the angular position of the bucket and the corresponding pressure distribution on the bucket computed by the numerical code are compared with that obtained experimentally. The comparison shows that numerical code based on MPS method is useful as a tool to gain an insight into the free surface flows in Pelton turbines.

  18. Investigation of seepage around the bucket skirt during installation in sand

    DEFF Research Database (Denmark)

    Koteras, Aleksandra Katarzyna; Ibsen, Lars Bo

    or along bucket skirt with known soil condition, bucket geometry and applied suction. The second aim of the study is to evaluate expressions for normalized seepage length, s/h, for different soil combinations and penetration depths. The seepage length is then 7 used to make a prediction of critical...... pressure that will create piping channels at exit, which is near to seabed and to the caisson wall, along bucket wall and at the tip. That is how the limits for suction installation can be assumed. Finally, the critical suction is used for predicting the reduction of penetration resistance and the method...... describing this approach is presented in the report with its assumptions. The method is called AAU CPT-based method and it is a great step in the development of practical design tool for bucket foundation installation process....

  19. Large regional differences in incidence of arthroscopic meniscal procedures in the public and private sector in Denmark

    DEFF Research Database (Denmark)

    Hare, Kristoffer Borbjerg; Vinther, Jesper Høeg; Lohmander, L Stefan

    2015-01-01

    OBJECTIVES: A recent study reported a large increase in the number of meniscal procedures from 2000 to 2011 in Denmark. We examined the nation-wide distribution of meniscal procedures performed in the private and public sector in Denmark since different incentives may be present and the use...... of these procedures may differ from region to region. SETTING: We included data on all patients who underwent an arthroscopic meniscal procedure performed in the public or private sector in Denmark. PARTICIPANTS: Data were retrieved from the Danish National Patient Register on patients who underwent arthroscopic...... for public and private procedures for each region. RESULTS: Incidence of meniscal procedures increased at private and at public hospitals. The private sector accounted for the largest relative and absolute increase, rising from an incidence of 1 in 2000 to 98 in 2011. In 2011, the incidence of meniscal...

  20. Physical Modelling of Bucket Foundation Under Long-Term Cyclic Lateral Loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo; Andersen, Lars Vabbersgaard

    2012-01-01

    Offshore wind farms are a promising renewable energy source. The monopod bucket foundation has the potential to become a reliable and cost-effective concept for offshore wind turbines. The bucket foundation must be designed by accounting for the cyclic loading which might endanger the turbine...... functioning. In this article a 1g physical model of bucket foundation under horizontal and moment cyclic loading is described. A testing program including four tests was carried out. Every test was conducted for at least 30000 cycles, each with different loading features. The capability of the model...

  1. The tear turnover and tear clearance tests - a review.

    Science.gov (United States)

    Garaszczuk, Izabela K; Montes Mico, Robert; Iskander, D Robert; Expósito, Alejandro Cerviño

    2018-03-01

    The aim is to provide a summary of methods available for the assessment of tear turnover and tear clearance rates. The review defines tear clearance and tear turnover and describes their implication for ocular surface health. Additionally, it describes main types of techniques for measuring tear turnover, including fluorescein tear clearance tests, techniques utilizing electromagnetic spectrum and tracer molecule and novel experimental techniques utilizing optical coherence tomography and fluorescein profilometry. Areas covered: Internet databases (PubMed, Science Direct, Google Scholar) and most frequently cited references were used as a principal resource of information on tear turnover rate and tear clearance rate, presenting methodologies and equipment, as well as their definition and implications for the anterior eye surface health and function. Keywords used for data-search were as follows: tear turnover, tear clearance, fluorescein clearance, scintigraphy, fluorophotometry, tear flow, drainage, tear meniscus dynamics, Krehbiel flow and lacrimal functional unit. Expert commentary: After decades, the topic of tear turnover assessment has been reintroduced. Recently, new techniques have been developed to propose less invasive, less time consuming and simpler methodologies for the assessment of tear dynamics that have the potential to be utilized in clinical practice.

  2. Large regional differences in incidence of arthroscopic meniscal procedures in the public and private sector in Denmark.

    Science.gov (United States)

    Hare, Kristoffer Borbjerg; Vinther, Jesper Høeg; Lohmander, L Stefan; Thorlund, Jonas Bloch

    2015-02-24

    A recent study reported a large increase in the number of meniscal procedures from 2000 to 2011 in Denmark. We examined the nation-wide distribution of meniscal procedures performed in the private and public sector in Denmark since different incentives may be present and the use of these procedures may differ from region to region. We included data on all patients who underwent an arthroscopic meniscal procedure performed in the public or private sector in Denmark. Data were retrieved from the Danish National Patient Register on patients who underwent arthroscopic meniscus surgery as a primary or secondary procedure in the years 2000 to 2011. Hospital identification codes enabled linkage of performed procedures to specific hospitals. Yearly incidence of meniscal procedures per 100,000 inhabitants was calculated with 95% CIs for public and private procedures for each region. Incidence of meniscal procedures increased at private and at public hospitals. The private sector accounted for the largest relative and absolute increase, rising from an incidence of 1 in 2000 to 98 in 2011. In 2011, the incidence of meniscal procedures was three times higher in the Capital Region than in Region Zealand. Our study identified a large increase in the use of meniscal procedures in the public and private sector in Denmark. The increase was particularly conspicuous in the private sector as its proportion of procedures performed increased from 1% to 32%. Substantial regional differences were present in the incidence and trend over time of meniscal procedures. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  3. Operation and maintenance techniques of 1 ton bucket elevator in IMEF

    International Nuclear Information System (INIS)

    Soong, Woong Sup

    1999-04-01

    IMEF pool is used as a pathway between pool and hot cell in order to transfer (incoming and outgoing) irradiated materials. Transfer is performed by 1 ton bucket elevator which is moved inside the rectangular tube installed between pool and M1 hot cell. Allowable load capacity is 1 ton of the bucket elevator and its size is 25 X 25 X 150 cm. Bucket is driven by chain system which is moved up and down through the guide rail. Guide rail is installed in rectangular tube that is tilted about 63 degree. Chain which is moved by using the roller sliding method is driven by sprocket wheel being rotated by the shaft and the shaft is driven by gear reducing motor. In this report operation and maintenance techniques of 1 ton bucket elevator in IMEF are described in detail. (Author). 8 refs., 14 tabs., 6 figs

  4. Operation and maintenance techniques of 1 ton bucket elevator in IMEF

    Energy Technology Data Exchange (ETDEWEB)

    Soong, Woong Sup

    1999-04-01

    IMEF pool is used as a pathway between pool and hot cell in order to transfer (incoming and outgoing) irradiated materials. Transfer is performed by 1 ton bucket elevator which is moved inside the rectangular tube installed between pool and M1 hot cell. Allowable load capacity is 1 ton of the bucket elevator and its size is 25 X 25 X 150 cm. Bucket is driven by chain system which is moved up and down through the guide rail. Guide rail is installed in rectangular tube that is tilted about 63 degree. Chain which is moved by using the roller sliding method is driven by sprocket wheel being rotated by the shaft and the shaft is driven by gear reducing motor. In this report operation and maintenance techniques of 1 ton bucket elevator in IMEF are described in detail. (Author). 8 refs., 14 tabs., 6 figs.

  5. Coal handling/storage in a sensitive environment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-04-01

    A leading Italian manufacturer Bedeschi has designed and built a coal handling plant for its Outao cement plant in an environmentally sensitive national park in Portugal, Setubal National Park. The receiving station is completely enclosed, to control dusts. The main 80 m{sup 3} hopper can receive several types of truck and an automatic dour seals off the receiving section as soon as the truck has left. Coals tend to be blended according to kiln requirements. A bucket-type reclaimer is used due to the sticky nature of the coal. 2 photos.

  6. On the robustness of bucket brigade quantum RAM

    Science.gov (United States)

    Arunachalam, Srinivasan; Gheorghiu, Vlad; Jochym-O'Connor, Tomas; Mosca, Michele; Varshinee Srinivasan, Priyaa

    2015-12-01

    We study the robustness of the bucket brigade quantum random access memory model introduced by Giovannetti et al (2008 Phys. Rev. Lett.100 160501). Due to a result of Regev and Schiff (ICALP ’08 733), we show that for a class of error models the error rate per gate in the bucket brigade quantum memory has to be of order o({2}-n/2) (where N={2}n is the size of the memory) whenever the memory is used as an oracle for the quantum searching problem. We conjecture that this is the case for any realistic error model that will be encountered in practice, and that for algorithms with super-polynomially many oracle queries the error rate must be super-polynomially small, which further motivates the need for quantum error correction. By contrast, for algorithms such as matrix inversion Harrow et al (2009 Phys. Rev. Lett.103 150502) or quantum machine learning Rebentrost et al (2014 Phys. Rev. Lett.113 130503) that only require a polynomial number of queries, the error rate only needs to be polynomially small and quantum error correction may not be required. We introduce a circuit model for the quantum bucket brigade architecture and argue that quantum error correction for the circuit causes the quantum bucket brigade architecture to lose its primary advantage of a small number of ‘active’ gates, since all components have to be actively error corrected.

  7. New Medium-Scale Laboratory Testing of Bucket Foundation Capacity in Sand

    DEFF Research Database (Denmark)

    Vaitkunaite, Evelina; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl

    2014-01-01

    This article presents a new testing rig for axially loaded bucket foundations. The medium-scale physical model gives the ability to examine the influence of axial tensile, compressive as well as cyclic loading on bucket foundations subjected to various levels of overburden stress. The properties...

  8. Buckling Analysis of Bucket Foundations for Wind Turbines in Deep Water

    DEFF Research Database (Denmark)

    Madsen, Søren; Andersen, Lars; Ibsen, Lars Bo

    2011-01-01

    Using large suction caissons for offshore wind turbines is an upcoming technology also referred to as bucket foundations. The bucket foundation does not require heavy installation equipment, but since it is constructed as a thin steel shell structure, instability, in form of buckling, becomes...

  9. Scour properties of mono bucket foundation

    DEFF Research Database (Denmark)

    Stroescu, Ionut Emanuel; Frigaard, Peter Bak

    2016-01-01

    Field experience proved that the Mono Bucket Foundations (MBFs) have good response against scour development. Moreover, the ratio between large diameter (bucket lid) and the small diameter (shaft tower) is the driving parameter for the process of erosion/backfill, like scour protection diameter...... in the case of scour protected monopiles. However, the structural design to reduce the scour development for MBFs is still open to optimization. The influences of parameters that generate backfill and scour, the transfer load webs and the misalignment with seabed, have not been systematically studied until...... analysis compared with real surveys and existing studies showed good agreements. Scour protection based on collar solution shows high efficiency when scour protection should be required. The paper demonstrates good agreement between field measurements and small-scale studies. The unique value of the field...

  10. Using combined system of shaft guides for buckets during shaft deepening

    Energy Technology Data Exchange (ETDEWEB)

    Durov, E.M.; Ivenskii, N.S.; Alekhin, P.I.

    1981-06-01

    This paper discusses a system of shaft guides used in the Krasnopol'evsk underground coal mine. The existing skip shaft 514 m deep is deepened to a depth of 700 m. Shaft design is adapted to a system of two pairs of skips, however, only one pair of skips is in operation and the other has been removed. The free space can be used to remove rock material from shaft bottom. It is noted that a system of buckets moving along elastic shaft guides made of rope or along rigid shaft guides can be used. Both solutions have numerous advantages. If rope guides are used time consuming installation of shaft guides is unnecessary in the zone close to the bottom. If rigid guides are used capacity of the bucket can be significantly increased. A system which combines advantages of both solutions is used: in the lower part of the shaft being deepened, buckets are guided by rope, and in the upper zone in which rigid shaft guides have been installed the bucket moves along rigid guides and rope guides simultaneously. Design of the element guiding the bucket is shown in two diagrams. It is noted that using the combined system of shaft guides increases capacity of the hoisting system by 1.5 times.

  11. A 12-week supervised exercise therapy program for young adults with a meniscal tear: Program development and feasibility study

    DEFF Research Database (Denmark)

    Skou, Søren T.; Thorlund, Jonas B.

    2018-01-01

    on clinical expertise and available evidence. Six patients (age range 22–39 years) considered eligible for meniscal surgery by an orthopedic surgeon underwent the program. Patients completed the Knee Injury and Osteoarthritis Outcome Score (KOOS) and evaluated the program during a semi-structured qualitative...... interview. Feedback from patients was included to finalize the exercise therapy program. Median improvements (Range) in KOOS subscales were 15 (0–33) for Pain, 11 (−11 to 50) for Symptoms, 16 (3–37) for Function in daily living, 23 (10–45) for Function in sport and recreation, and 9 (−6 to 31) for Quality...... of life. The patients found the program relevant and effective with only a few short-lasting adverse events and important clinical improvements after four to ten weeks. Physical therapist supervision was considered important. No patients wanted surgery up to 6 month after the exercise therapy program...

  12. Bucket wheel excavators for open-cast mining all over the world

    Energy Technology Data Exchange (ETDEWEB)

    Durst, W.

    1979-04-01

    A report is given on the use of bucket wheel excavators, spreaders and tripper cars in open-cast mining of brown coal, oilsand and other minerals in Australia, Canada, India, Spain, USA and Yugoslavia as well as on the use of bucket wheel excavators for land reclamation in Singapore.

  13. First-stage high pressure turbine bucket airfoil

    Science.gov (United States)

    Brown, Theresa A.; Ahmadi, Majid; Clemens, Eugene; Perry, II, Jacob C.; Holiday, Allyn K.; Delehanty, Richard A.; Jacala, Ariel Caesar

    2004-05-25

    The first-stage buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein Z is a perpendicular distance from a plane normal to a radius of the turbine centerline and containing the X and Y values with the Z value commencing at zero in the X, Y plane at the radially innermost aerodynamic section of the airfoil and X and Y are coordinates defining the airfoil profile at each distance Z. The X, Y and Z values may be scaled as a function of the same constant or number to provide a scaled-up or scaled-down airfoil section for the bucket.

  14. An anatomical study of normal meniscal roots with isotropic 3D MRI at 3 T

    International Nuclear Information System (INIS)

    Ren Ahong; Zheng Zhuozhao; Shang Yao; Tian Chunyan

    2012-01-01

    Objectives: To clarify the morphological features of normal meniscal roots on magnetic resonance (MR) imaging with an isotropic 3D proton density-weighted (PDW) sequence. Materials: 3D PDW MR was performed in sixty-two patients at 3 T before knee arthroscopy. MR images of 34 normal medial menisci and 33 intact lateral menisci confirmed by arthroscopy were retrospectively evaluated. MR signals, insertion sites, dimensions and courses of four meniscal roots were recorded. Results: The anterior root of medial meniscus (ARMM) was typically hypointense, while the posterior root of medial meniscus (PRMM) and the anterior root of lateral meniscus (ARLM) were prone to be hyperintense or showing a comblike signal, and the posterior root of lateral meniscus (PRLM) was usually hypointense or comblike on PDW MR images. ARMM and PRLM had more complex and diverse insertion patterns than ARLM and PRMM. There were significant statistical differences of the lengths, widths, heights and course angles among four meniscal roots (all P < 0.001). Conclusions: The signal intensity of each meniscal root can be hypointense, hyperintense, or comblike on 3D PDW MR images. ARMM and PRLM have more complex and diverse insertion patterns than ARLM and PRMM. The dimensions and courses of four meniscal roots all differ.

  15. A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis

    Directory of Open Access Journals (Sweden)

    Nicolas Lefevre

    2016-01-01

    Full Text Available The main objective of this review was to present a synthesis of the current literature in order to provide a useful tool to clinician in radiologic analysis of the meniscus. All anatomical descriptions were clearly illustrated by MRI, arthroscopy, and/or drawings. The value of standard radiography is extremely limited for the assessment of meniscal injuries but may be indicated to obtain a differential diagnosis such as osteoarthritis. Ultrasound is rarely used as a diagnostic tool for meniscal pathologies and its accuracy is operator-dependent. CT arthrography with multiplanar reconstructions can detect meniscus tears that are not visible on MRI. This technique is also useful in case of MRI contraindications, in postoperative assessment of meniscal sutures and the condition of cartilage covering the articular surfaces. MRI is the most accurate and less invasive method for diagnosing meniscal lesions. MRI allows confirming and characterizing the meniscal lesion, the type, the extension, its association with a cyst, the meniscal extrusion, and assessing cartilage and subchondral bone. New 3D-MRI in three dimensions with isotropic resolution allows the creation of multiplanar reformatted images to obtain from an acquisition in one sectional plane reconstructions in other spatial planes. 3D MRI should further improve the diagnosis of meniscal tears.

  16. A Current Review of the Meniscus Imaging: Proposition of a Useful Tool for Its Radiologic Analysis

    Science.gov (United States)

    Lefevre, Nicolas; Naouri, Jean Francois; Herman, Serge; Gerometta, Antoine; Klouche, Shahnaz; Bohu, Yoann

    2016-01-01

    The main objective of this review was to present a synthesis of the current literature in order to provide a useful tool to clinician in radiologic analysis of the meniscus. All anatomical descriptions were clearly illustrated by MRI, arthroscopy, and/or drawings. The value of standard radiography is extremely limited for the assessment of meniscal injuries but may be indicated to obtain a differential diagnosis such as osteoarthritis. Ultrasound is rarely used as a diagnostic tool for meniscal pathologies and its accuracy is operator-dependent. CT arthrography with multiplanar reconstructions can detect meniscus tears that are not visible on MRI. This technique is also useful in case of MRI contraindications, in postoperative assessment of meniscal sutures and the condition of cartilage covering the articular surfaces. MRI is the most accurate and less invasive method for diagnosing meniscal lesions. MRI allows confirming and characterizing the meniscal lesion, the type, the extension, its association with a cyst, the meniscal extrusion, and assessing cartilage and subchondral bone. New 3D-MRI in three dimensions with isotropic resolution allows the creation of multiplanar reformatted images to obtain from an acquisition in one sectional plane reconstructions in other spatial planes. 3D MRI should further improve the diagnosis of meniscal tears. PMID:27057352

  17. Injection Bucket Jitter Compensation Using Phase Lock System at Fermilab Booster

    Energy Technology Data Exchange (ETDEWEB)

    Seiya, K. [Fermilab; Drennan, C. [Fermilab; Pellico, W. [Fermilab; Chaurize, S. [Fermilab

    2017-05-12

    The extraction bucket position in the Fermilab Booster is controlled with a cogging process that involves the comparison of the Booster rf count and the Recycler Ring revolution marker. A one rf bucket jitter in the ex-traction bucket position results from the variability of the process that phase matches the Booster to the Recycler. However, the new slow phase lock process used to lock the frequency and phase of the Booster rf to the Recycler rf has been made digital and programmable and has been modified to correct the extraction notch position. The beam loss at the Recycler injection has been reduced by 20%. Beam studies and the phase lock system will be discussed in this paper.

  18. Meniscal Allograft Transplantation Does Not Prevent or Delay Progression of Knee Osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Catherine Van Der Straeten

    Full Text Available Meniscal tears are common knee injuries. Meniscal allograft transplantation (MAT has been advocated to alleviate symptoms and delay osteoarthritis (OA after meniscectomy. We investigated (1 the long-term outcome of MAT as a treatment of symptomatic meniscectomy, (2 most important factors affecting survivorship and (3 OA progression.From 1989 till 2013, 329 MAT were performed in 313 patients. Clinical and radiographic results and MAT survival were evaluated retrospectively. Failure was defined as conversion to knee arthroplasty (KA or total removal of the MAT.Mean age at surgery was 33 years (15-57; 60% were males. No-to-mild cartilage damage was found in 156 cases, moderate-to-severe damage in 130. Simultaneous procedures in 118 patients included cartilage procedures, osteotomy or ACL-reconstruction. At a mean follow-up of 6.8 years (0.2-24.3years, 5 patients were deceased and 48 lost (14.6%, 186 MAT were in situ (56.5% whilst 90 (27.4% had been removed, including 63 converted to a KA (19.2%. Cumulative allograft survivorship was 15.1% (95% CI:13.9-16.3 at 24.0 years. In patients <35 years at surgery, survival was significantly better (24.1% compared to ≥35 years (8.0% (p = 0.017. In knees with no-to-mild cartilage damage more allografts survived (43.0% compared to moderate-to-severe damage (6.6% (p = 0.003. Simultaneous osteotomy significantly deteriorated survival (0% at 24.0 years (p = 0.010. 61% of patients underwent at least one additional surgery (1-11 for clinical symptoms after MAT. Consecutive radiographs showed significant OA progression at a mean of 3.8 years (p<0.0001. Incremental Kellgren-Lawrence grade was +1,1 grade per 1000 days (2,7yrs.MAT did not delay or prevent tibiofemoral OA progression. 19.2% were converted to a knee prosthesis at a mean of 10.3 years. Patients younger than 35 with no-to-mild cartilage damage may benefit from MAT for relief of symptoms (survivorship 51.9% at 20.2 years, but patients and healthcare payers

  19. Physical Modelling of Bucket Foundations Subjected to Axial Loading

    DEFF Research Database (Denmark)

    Vaitkunaite, Evelina

    Compared to oil and gas structures, marine renewable energy devices are usually much lighter, operate in shallower waters and are subjected to severe cyclic loading and dynamic excitations. These factors result in different structural behaviours. Bucket foundations are a potentially cost......-effective solution for various offshore structures, and not least marine renewables. The present thesis focuses on several critical design problems related to the behaviour of bucket foundations exposed to tensile loading. Among those are the soil-structure interface parameters, tensile loading under various...

  20. Discrimination of meniscal cell phenotypes using gene expression profiles

    Directory of Open Access Journals (Sweden)

    M Son

    2012-03-01

    Full Text Available The lack of quantitative and objective metrics to assess cartilage and meniscus cell phenotypes contributes to the challenges in fibrocartilage tissue engineering. Although functional assessment of the final resulting tissue is essential, initial characterization of cell sources and quantitative description of their progression towards the natural, desired cell phenotype would provide an effective tool in optimizing cell-based tissue engineering strategies. The purpose of this study was to identify quantifiable characteristics of meniscal cells and thereby find phenotypical markers that could effectively categorize cells based on their tissue of origin (cartilage, inner, middle, and outer meniscus. The combination of gene expression ratios collagen VI/collagen II, ADAMTS-5/collagen II, and collagen I/collagen II was the most effective indicator of variation among different tissue regions. We additionally demonstrate a possible application of these quantifiable metrics in evaluating the use of serially passaged chondrocytes as a possible cell source in fibrocartilage engineering. Comparing the ratios of the passaged chondrocytes and the native meniscal cells may provide direction to optimize towards the desired cell phenotype. We have thus shown that measurable markers defining the characteristics of the native meniscus can establish a standard by which different tissue engineering strategies can be objectively assessed. Such metrics could additionally be useful in exploring the different stages of meniscal degradation in osteoarthritis and provide some insight in the disease progression.

  1. A Study on the Optimum Bucket Size for Master Scheduling : For the Case of Hierarchically tured Products

    OpenAIRE

    木内, 正光

    2010-01-01

    The function of master scheduling is to plan the flow of order from its arrival to its completion. In this study, the problem of bucket size for master scheduling is taken up. The bucket size for master scheduling has much influence on the lead time of the order. However, to date there is no clear method for how to set the optimum bucket size. The purpose of this study is to propose a method to set the optimum bucket size. In this paper, an equation to estimate the optimum bucket size is prop...

  2. Computational analysis of Pelton bucket tip erosion using digital image processing

    Science.gov (United States)

    Shrestha, Bim Prasad; Gautam, Bijaya; Bajracharya, Tri Ratna

    2008-03-01

    Erosion of hydro turbine components through sand laden river is one of the biggest problems in Himalayas. Even with sediment trapping systems, complete removal of fine sediment from water is impossible and uneconomical; hence most of the turbine components in Himalayan Rivers are exposed to sand laden water and subject to erode. Pelton bucket which are being wildly used in different hydropower generation plant undergoes erosion on the continuous presence of sand particles in water. The subsequent erosion causes increase in splitter thickness, which is supposed to be theoretically zero. This increase in splitter thickness gives rise to back hitting of water followed by decrease in turbine efficiency. This paper describes the process of measurement of sharp edges like bucket tip using digital image processing. Image of each bucket is captured and allowed to run for 72 hours; sand concentration in water hitting the bucket is closely controlled and monitored. Later, the image of the test bucket is taken in the same condition. The process is repeated for 10 times. In this paper digital image processing which encompasses processes that performs image enhancement in both spatial and frequency domain. In addition, the processes that extract attributes from images, up to and including the measurement of splitter's tip. Processing of image has been done in MATLAB 6.5 platform. The result shows that quantitative measurement of edge erosion of sharp edges could accurately be detected and the erosion profile could be generated using image processing technique.

  3. MRI EVALUATION OF INTERNAL DERANGEMENT OF KNEE

    Directory of Open Access Journals (Sweden)

    Ashok Srikar Chowdhary

    2018-01-01

    Full Text Available BACKGROUND Internal derangement of knee means loss of normal knee function due to ligament or meniscal injuries. MRI is a routinely utilised noninvasive modality for evaluation of various knee disorders including internal derangement. MRI provides excellent soft tissue contrast and multiplanar images when compared to other musculoskeletal imaging modalities. The aim of the study is to study the demographic profile of patients presenting with internal derangement of knee, identify the various ligament and meniscal injuries causing internal derangement of knee and describe the MRI features of the ligament and meniscal injuries. MATERIALS AND METHODS This study was undertaken from January 2016 to mid-December 2017 in the Department of Radiodiagnosis, MVJ Medical College and Research Hospital, Hoskote. The study population consisted of 108 patients with internal derangement of knee who underwent MRI of knee. All the MRI scans of the knee in this study were performed using Siemens Magnetom Essenza (A Tim+Dot system MR machine with a 1.5 tesla field strength magnet using a flex coil. RESULTS The study population consisted of 108 patients comprising of 90 males and 18 females. The age of the patients ranged from 16 to 67 years. Majority of the patients belonged to the age group of 21-30 years constituting about 41% of the total study population. Anterior cruciate ligament injury was the commonest followed by medial and lateral meniscus tears. Flap tear was the commonest type of meniscal tear. Posterior horn of the meniscus was the commonest tear site. CONCLUSION MRI is the investigation of choice in evaluating internal derangement of knee. MRI can accurately diagnose ligament and meniscal injuries and guide arthroscopy.

  4. Effect of embedment on the plastic behaviour of Bucket Foundations

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Barari, Amin; Larsen, Kim André

    2015-01-01

    studies have indicated the possibility of defining foundation response using plasticity theory. Results of multiple loading tests addressing the effect of embedment on the strain-hardening behavior of shallow bucket foundations under combined loading are reported. The kinematic mechanisms accompanying pre......-failure are presented. It is argued that the drained capacity of offshore bucket foundations and the ratio of plastic increments are largely influenced by embedment depth and the preload ratio V/Vpeak....

  5. As tears go by : Baby tears trigger more brain activity than adult tears in nulliparous women

    NARCIS (Netherlands)

    Hendricx-Riem, M.M.E.; De Carli, P.; van IJzendoorn, M.H.; Vingerhoets, A.J.J.M.; Bakermans-Kranenburg, M.J.

    2017-01-01

    The current functional magnetic resonance imaging study examines brain activity during the perception of infant and adult tears. Infant tears evoke stronger responses in the visual cortex than adult tears, indicating that infant tears are highly salient. In addition, our study shows that infant

  6. Biological knee reconstruction for combined malalignment, meniscal deficiency, and articular cartilage disease.

    Science.gov (United States)

    Harris, Joshua D; Hussey, Kristen; Wilson, Hillary; Pilz, Kyle; Gupta, Anil K; Gomoll, Andreas; Cole, Brian J

    2015-02-01

    The aim of this study was to analyze patient-reported outcomes in those undergoing the triad of simultaneous osteotomy, meniscal transplantation, and articular cartilage repair. Patients undergoing simultaneous meniscal transplantation, distal femoral or proximal tibial osteotomy, and articular cartilage surgery by a single surgeon (B.J.C.) were analyzed. Meniscal transplantation was performed using bone-in-slot techniques. Distal femoral and high tibial osteotomies were performed for valgus and varus malalignment, respectively. Microfracture, autologous chondrocyte implantation, and osteochondral autograft or allograft were performed for articular cartilage disease. Validated patient-reported and surgeon-measured outcomes were collected. Preoperative and postoperative outcomes and medial versus lateral disease were compared using Student t tests. Eighteen participants (mean age, 34 ± 7.8 years; symptomatic patients, 7.4 ± 5.6 years; 2.4 ± 1.0 surgical procedures before study enrollment; mean follow-up, 6.5 ± 3.2 years) were analyzed. Two thirds of participants had medial compartment pathologic conditions and one third had lateral compartment pathologic processes. At final follow-up, there were statistically significant clinically meaningful improvements in International Knee Documentation Committee (IKDC) subjective classification, Lysholm score, and 4 Knee Injury and Osteoarthritis Outcome Score (KOOS) subscores. Postoperative 12-item short form (SF-12) physical and mental component scores were not significantly different from preoperative scores. The Kellgren-Lawrence classification grade was 1.5 ± 1.1 at 2.5 ± 3.0 years after surgery. There was a significantly higher preoperative SF-12 physical composite score (PCS) in participants with lateral compartment pathologic conditions (v medial compartment conditions) (P = .011). Although there were 13 reoperations in 10 patients (55.5% reoperation rate), only one patient was converted to knee arthroplasty (5

  7. Do MRI features at baseline predict radiographic joint space narrowing in the medial compartment of the osteoarthritic knee 2 years later?

    Energy Technology Data Exchange (ETDEWEB)

    Madan-Sharma, Ruby; Kornaat, Peter R.; Bloem, Johannes L.; Watt, Iain [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Kloppenburg, Margreet; Botha-Scheepers, Stella A. [Leiden University Medical Center, Department of Rheumatology, Leiden (Netherlands); Graverand, Marie-Pierre Hellio le [Pfizer Groton, Groton, CT (United States)

    2008-09-15

    The purpose of the study was to relate magnetic resonance imaging (MRI) features at baseline with radiographically determined joint space narrowing (JSN) in the medial compartment of the knee after 2 years in a group of patients with symptomatic osteoarthritis at multiple joint sites. MRI of the knee and standardized radiographs were obtained at baseline and after 2 years in 186 patients (81% female; aged 43-76 years; mean 60 years). MRI was analyzed for bone marrow lesions, cysts, osteophytes, hyaline cartilage defects, joint effusion, and meniscal pathology in the medial compartment. Radiographs were scored semiquantitatively for JSN in the medial tibiofemoral joint using the Osteoarthritis Research Society International (OARSI) atlas. Radiological progression was defined as {>=}1 grade increase. Associations between baseline magnetic resonance (MR) parameters and subsequent radiographic JSN changes were assessed using logistic regression. Relative risk (RR) was then calculated. Radiographic progression of JSN was observed in 17 (9.1%) of 186 patients. Eleven patients had a Kellgren and Lawrence (KL) score of {>=}2. A significant association was observed between all patients and meniscal tears (RR 3.57; confidence interval (CI) 1.08-10.0) and meniscal subluxation (RR 2.73; CI 1.20-5.41), between KL<2 and meniscal subluxation (RR 11.3; CI 2.49-29.49) and KL {>=} 2 and meniscus tears (RR 8.91; CI 1.13-22.84) and radiographic JSN 2 years later. Follow-up MR in 15 of 17 patients with progressive JSN showed only new meniscal abnormalities and no progression of cartilage loss. Meniscal pathology (tears and/or meniscal subluxation) was the only MRI parameter to be associated with subsequent radiographic progression of JSN in the medial tibiofemoral compartment on a radiograph 2 years later, as assessed by the OARSI score. (orig.)

  8. BBAT: Bunch and bucket analysis tool

    International Nuclear Information System (INIS)

    Deng, D.P.

    1995-01-01

    BBAT is written to meet the need of an interactive graphical tool to explore the longitudinal phase space. It is driven for testing new ideas or new tricks quickly. It is especially suitable for machine physicists or operation staff as well both in the control room during machine studies or off-line to analyze the data. The heart of the package contains a set of c-routines to do the number crunching. The graphics part is wired with scripting language tcl/tk and BLT. The c-routines are general enough that one can write new applications such as animation of the bucket as a machine parameter varies via a sliding scale. BBAT deals with single rf system. For double rf system, one can use Dr. BBAT, which stands for Double rf Bunch and Bucket Analysis Tool. One usage of Dr. BBAT is to visualize the process of bunch coalescing and flat bunch creation

  9. Airfoil shape for a turbine bucket

    Science.gov (United States)

    Hyde, Susan Marie; By, Robert Romany; Tressler, Judd Dodge; Schaeffer, Jon Conrad; Sims, Calvin Levy

    2005-06-28

    Third stage turbine buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth Table I wherein X and Y values are in inches and the Z values are non-dimensional values from 0 to 0.938 convertible to Z distances in inches by multiplying the Z values by the height of the airfoil in inches. The X and Y values are distances which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z. The profile sections at each distance Z are joined smoothly to one another to form a complete airfoil shape. The X and Y distances may be scalable as a function of the same constant or number to provide a scaled up or scaled down airfoil section for the bucket. The nominal airfoil given by the X, Y and Z distances lies within an envelop of .+-.0.150 inches in directions normal to the surface of the airfoil.

  10. Torsional Moment Measurement on Bucket Wheel Shaft of Giant Machine

    Directory of Open Access Journals (Sweden)

    Jiří FRIES

    2011-06-01

    Full Text Available Bucket wheel loading at the present time (torsional moment on wheel shaft, peripheral cutting force is determined from electromotor incoming power or reaction force measured on gearbox hinge. Both methods together are weighted by steel construction absorption of driving units and by inertial forces of motor rotating parts. In the article is described direct method of the torsional moment measurement, which eliminates mentioned unfavourable impacts except absorption of steel construction of bucket wheel itself.

  11. Flow simulation of a Pelton bucket using finite volume particle method

    International Nuclear Information System (INIS)

    Vessaz, C; Jahanbakhsh, E; Avellan, F

    2014-01-01

    The objective of the present paper is to perform an accurate numerical simulation of the high-speed water jet impinging on a Pelton bucket. To reach this goal, the Finite Volume Particle Method (FVPM) is used to discretize the governing equations. FVPM is an arbitrary Lagrangian-Eulerian method, which combines attractive features of Smoothed Particle Hydrodynamics and conventional mesh-based Finite Volume Method. This method is able to satisfy free surface and no-slip wall boundary conditions precisely. The fluid flow is assumed weakly compressible and the wall boundary is represented by one layer of particles located on the bucket surface. In the present study, the simulations of the flow in a stationary bucket are investigated for three different impinging angles: 72°, 90° and 108°. The particles resolution is first validated by a convergence study. Then, the FVPM results are validated with available experimental data and conventional grid-based Volume Of Fluid simulations. It is shown that the wall pressure field is in good agreement with the experimental and numerical data. Finally, the torque evolution and water sheet location are presented for a simulation of five rotating Pelton buckets

  12. Cine MR imaging of internal derangements of the knee

    International Nuclear Information System (INIS)

    Niitsu, M.; Anno, I.; Ishikawa, N.; Akisada, M.; Fukubayashi, T.

    1990-01-01

    This paper assesses internal derangements of the knee joint by a new method of cine MR imaging. Cine MR imaging, involving cine acquisition of kinematic sagittal images during knee movement, was used to evaluate 51 symptomatic patients and 19 healthy subjects. Cine MR images of cruciate ligament fears showed disappearance of low-intensity bundles during knee movement, periodic appearance of joint fluid in the area of the ligament, and irregular tibial movement. Cine MR images of meniscal tears showed independent movement of meniscal fragments and periodic tear opening and closing. Twenty-seven of the 28 anterior cruciate ligament (ACL) tears confirmed arthroscopically were correctly identified with cine MR imaging, with a sensitivity of 96% and a specificity of 92%

  13. Gated current integrator for the beam in the RR barrier buckets

    Energy Technology Data Exchange (ETDEWEB)

    A. Cadorn; C. Bhat; J. Crisp

    2003-06-10

    At the Fermilab Recycler Ring (RR), the antiproton (pbar) beam will be stored azimuthally in different segments created by barrier buckets. The beam in each segment may have widely varying intensities. They have developed a gated integrator system to measure the beam intensity in each of the barrier bucket. Here they discuss the design of the system and the results of beam measurements using the integrator.

  14. Forward lunge knee biomechanics before and after partial meniscectomy

    DEFF Research Database (Denmark)

    Hall, Michelle; Nielsen, Jonas Høberg; Holsgaard-Larsen, Anders

    2015-01-01

    partial meniscectomy (APM) on knee joint mechanics. The purpose of this study was to evaluate changes in knee joint biomechanics during a forward lunge in patients with a suspected degenerative meniscal tear from before to three months after APM. METHODS: Twenty-two patients (35-55years old......) with a suspected degenerative medial meniscal tear participated in this study. Three dimensional knee biomechanics were assessed on the injured and contralateral leg before and three months after APM. The visual analogue scale was used to assess knee pain and the Knee Injury Osteoarthritis Outcome Score was used...

  15. MRI of the knee: how do field strength and radiologist's experience influence diagnostic accuracy and interobserver correlation in assessing chondral and meniscal lesions and the integrity of the anterior cruciate ligament?

    International Nuclear Information System (INIS)

    Krampla, W.; Roesel, M.; Svoboda, K.; Nachbagauer, A.; Gschwantler, M.; Hruby, W.

    2009-01-01

    Accuracy of MRI reports is taken for granted. In this paper the inter-observer reliability in the interpretation of meniscal lesions, degree of chondropathy, and integrity of the ACL was analyzed while taking the radiologist's experience and field strength into account. Fifty-two MRI studies of knees were interpreted by 11 radiologists independently. Twenty-two were acquired on 1.0-T, 20 on 1.5-T, and 10 on 3.0-T systems. Four of the radiologists had more than 5 years and seven had 3 to 5 years of experience in interpreting MRI studies. The findings were compared with the intra-operative findings. Inter-observer variance, specificity, and sensitivity were evaluated for each field strength. Inter-observer correlation ranged between 0.370 for cartilage lesions and 0.597 for meniscal tears. Correlation values did not increase with experience or field strength. The number of false reports was dependent on the observer, but not on field strength. The rate of false interpretations was significantly higher for most criteria in the less experienced group. In conclusion, inter-observer correlation was low, although the diagnostic criteria were defined. The use of the classification scheme should be standardized by uniform training. Radiologist experience seems to be more important than field strength. (orig.)

  16. Cavitation phenomena occurring on Pelton turbines buckets. Part 1

    International Nuclear Information System (INIS)

    Brivio, R.; Zappi, O.

    1995-01-01

    The article takes into consideration the erosion and/or cavitation phenomena occurring on the Pelton turbine buckets. It describes the main geometrical parameters that can cause the deterioration of the hydraulic profile and the provisions taken for avoid it or at least reduce it at the minimum when this deterioration has taken place. Furthermore, this article describes the development of the profiles up to the definition of bucket shapes that can assure high efficiencies and lack of cavitation. Some significant results, obtained about ten years ago in the hydraulic laboratory utilizing a closed circuit and reduced scale models, are then illustrated

  17. Forces acting on particles in a Pelton bucket and similarity considerations for erosion

    Science.gov (United States)

    Rai, A. K.; Kumar, A.; Staubli, T.

    2016-11-01

    High sediment transport rates cause severe erosion issues in hydropower plants leading to interruptions in power generation, decrease in efficiency and shutdown for repair and maintenance. For Pelton turbines operating at high head, the issue of erosion is severe, especially in components like buckets, nozzle rings and needles. Goal of the study is to develop erosion focussed guidelines for both designing as well as operating hydropower plants with Pelton runners. In this study, the flow of sediment inside a Pelton bucket with respect to forces acting on solid particles is analysed with an analytical approach by considering different dynamic forces originating from the rotation of the turbine, the curvature of the buckets, and the Coriolis effect. Further, the path of sediment particles and its effect on erosion phenomena are analysed based on the process of separation of different sized sediment particles from streamlines. The data relating to head, power, discharge, number of jet and efficiency of 250 hydropower plants installed all over the world were analysed in this study to find the major factors related to erosion in Pelton turbine bucket. From analysis of different force ratios, it is found that an increase of D/B, i.e. the ratio of pitch circle diameter and bucket width, and/or decrease of specific speed (nq) enhances erosion. As the erosion process depends significantly on nondimensional parameters D/B and nq, these are considered as similarity measures for scaling of the erosion process in the Pelton buckets of various sizes.

  18. Energy dissipation of slot-type flip buckets

    Science.gov (United States)

    Wu, Jian-hua; Li, Shu-fang; Ma, Fei

    2018-03-01

    The energy dissipation is a key index in the evaluation of energy dissipation elements. In the present work, a flip bucket with a slot, called the slot-type flip bucket, is theoretically and experimentally investigated by the method of estimating the energy dissipation. The theoretical analysis shows that, in order to have the energy dissipation, it is necessary to determine the sequent flow depth h 1 and the flow speed V 1 at the corresponding position through the flow depth h 2 after the hydraulic jump. The relative flow depth h 2 / h 。 is a function of the approach flow Froude number Fr 。, the relative slot width b/B 。, and the relative slot angle θ/β. The expression for estimating the energy dissipation is developed, and the maximum error is not larger than 9.21%.

  19. Modified Expression for the Failure Criterion of Bucket Foundations Subjected to Combined Loading

    DEFF Research Database (Denmark)

    Larsen, Kim André; Ibsen, Lars Bo; Barari, Amin

    2013-01-01

    Recently, various loading tests with small- and large-scale bucket foundations were performed on buckets of varying sizes, embedment ratios, and load paths with saturated dense Aalborg University Sand No. 1 at the geotechnical laboratory of Aalborg University. In the present study, the capacity a...

  20. Study on the Bearing Mode and Force Transfer Path of Composite Bucket Foundations

    Directory of Open Access Journals (Sweden)

    Shaohua He

    2017-07-01

    Full Text Available This paper elaborates on a new composite bucket foundation (CBF structural system for offshore wind turbines. The proposed CBF consists of a special force transition section, a beam system structure upper steel bucket cover and a large-scale steel bucket with honeycomb structure rooms. It can be prefabricated onshore, self-floated on the sea and then towed to the appointed sea area before sinking to the sea soil under negative pressure. This is called the “one-step” installation technology. Arc- and line-type bucket foundations are calculated by both theory and the finite element method to discuss their force transfer paths and bearing modes. Owning to the special structural form, the transition section can effectively convert the huge load and bending moment into controllable tension and compressive stress, as well as adjust the structure balance. The bearing model and percentage of each part of the composite foundation under monotonous and ultimate load conditions are also calculated. Results indicate that the bearing mode of CBF is a typical top cover mode. In addition, the curvature impact of arc-type is studied and the results reveal that the structure type of the transition section is more important than the diameter ratio between the bottom transition section and the bucket.

  1. Transiently Loaded Bucket Foundations in Saturated Dense Sand - Demonstration of the Boot Effect

    DEFF Research Database (Denmark)

    Nielsen, Søren Dam; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl

    2017-01-01

    The mono bucket foundation is a cost-effective foundation for offshore wind turbines. During a storm, these foundations are exposed to large wave loads of short duration. This paper investigates the effect of increased loading rate on the bearing capacity of two mono bucket foundations installed ...

  2. Anterior cruciate ligament tear: comparison of MR features between complete and partial tear

    International Nuclear Information System (INIS)

    Song, Ki Young; Lee, Joo Hyuk; Park, Jin Hee; Lee, Yu Jin; Rho, Eun Jin; Kim, Young Hoon; Yi, Jeong Geun; Ahn, Joong Mo

    1997-01-01

    To determine the MRI features which distinguish complete and partial tear of the anterior cruciate ligament(ACL) and to thus improve MRI interpretation. In 80 patients, we analyzed MR findings of direct and indirect signs of ACL tear (complete tear, 61 cases, partial tear, 19 cases) confirmed by arthroscopy or surgery, and compared the relative incidence of each sign in cases of complete and partial tear. Direct and indirect signs were found in 61 (100%) and 60 cases (98.4%), respectively, in complete tears, but in 16 (84.2%) and 15 cases (78.9%), respectively, in partial tears. Poor visualization, discontinuity and hyperintensity were seen in all complete tears but in only nine cases (47.4%) of partial tear. A wavy or abnormal contour was seen in 53 cases (86.9%) of complete tear and 14 (73.7%) of partial tear. A wavy contour without other direct signs was seen in only five cases (26.3%) of partial tear. Three cases (15.8%) of partial tear showed normal MR finding. Indirect signs, i.e. abnormal ACL angle, abnormal ACL-Blumensaat line angle, abnormal posterior cruciate ligament (PCL) line, abnormal PCL angle, PCL buckling, anterior displacement of tibia, posterior displacement of lateral meniscus, bone bruise, Segond fracture, tear of collateral ligaments, PCL, and tear of meniscus were commoner in complete than in partial tears. Two cases of O'Donoghue's triad and two of popliteus injury were seen only in complete tears. Direct and indirect signs of ACL tear were more commonly noted in complete than in partial tears. The latter showed MR features varying from normal to almost complete tear. We suggest that a wavy contour without other direct signs is indicative of a partial tear, and that O'Donoghue's triad and popliteus muscle injury are indirect signs of a complete tear

  3. Streaming tearing mode

    Science.gov (United States)

    Shigeta, M.; Sato, T.; Dasgupta, B.

    1985-01-01

    The magnetohydrodynamic stability of streaming tearing mode is investigated numerically. A bulk plasma flow parallel to the antiparallel magnetic field lines and localized in the neutral sheet excites a streaming tearing mode more strongly than the usual tearing mode, particularly for the wavelength of the order of the neutral sheet width (or smaller), which is stable for the usual tearing mode. Interestingly, examination of the eigenfunctions of the velocity perturbation and the magnetic field perturbation indicates that the streaming tearing mode carries more energy in terms of the kinetic energy rather than the magnetic energy. This suggests that the streaming tearing mode instability can be a more feasible mechanism of plasma acceleration than the usual tearing mode instability.

  4. Comparison of a pneumatic conveyor and bucket elevator on an energy and economic basis

    Energy Technology Data Exchange (ETDEWEB)

    Rothwell, T.M.; Southwell, P.H. (Agricultural and Energy Engineering Ltd., Moorefield, ON (Canada)); Vigneault, C. (Agricultural Canada Research Station, St-Jean-sur-Richelieu, PQ (Canada))

    1991-07-01

    Tests were performed at a commercial feed mill which was replacing an existing pneumatic conveyor with a bucket elevator, in order to compare the performance of the two types of conveyor on an energy and cost basis. The conveyors were used to transport ground corn from a hammermill at an average grinding rate of 8.5 tonnes/h. At the same conveying rate of ground product, the pneumatic conveyor required a power of 27.5 kW and an energy of 4.77 kWh/tonne while the bucket elevator required a power of 4.7 kW and an energy of 0.88 kWh/tonne. The financial costs of conveying energy were $8,350/y for the pneumatic system and $1,540/y for the bucket elevator, excluding peak demand charges for electricity. The tests therefore demonstrated that a bucket elevator is far more efficient than a pneumatic conveyor and should be considered in the design of new feed mills. For existing mills, a bucket elevator should be considered if there are problems with the pneumatic system already in place or if the capacity of the mill needs to be increased. 2 refs., 2 tabs.

  5. Mass spectrometric identification of phospholipids in human tears and tear lipocalin.

    Science.gov (United States)

    Dean, Austin W; Glasgow, Ben J

    2012-04-02

    The purpose of this article was to identify by mass spectrometry phosphocholine lipids in stimulated human tears and determine the molecules bound to tear lipocalin or other proteins. Tear proteins were separated isocratically from pooled stimulated human tears by gel filtration fast performance liquid chromatography. Separation of tear lipocalin was confirmed by SDS tricine gradient PAGE. Protein fractions were extracted with chloroform/methanol and analyzed with electrospray ionization MS/MS triple quadrupole mass spectrometry in precursor ion scan mode for select leaving groups. For quantification, integrated ion counts were derived from standard curves of authentic compounds of phosphatidylcholine (PC) and phosphatidylserine. Linear approximation was possible from integration of the mass spectrometrically obtained ion peaks at 760 Da for the PC standard. Tears contained 194 ng/mL of the major intact PC (34:2), m/z 758.6. Ten other monoisotopic phosphocholines were found in tears. A peak at 703.3 Da was assigned as a sphingomyelin. Four lysophosphatidylcholines (m/z 490-540) accounted for about 80% of the total integrated ion count. The [M+H](+) compound, m/z 496.3, accounted for 60% of the signal intensity. Only the tear lipocalin-bearing fractions showed phosphocholines (104 ng/mL). Although the intact phospholipids bound to tear lipocalin corresponded precisely in mass and relative signal intensity to that found in tears, we did not identify phosphocholines between m/z 490 and 540 in any of the gel-filtration fractions. Phospholipids, predominantly lysophospholipids, are present in tears. The higher mass intact PCs in tears are native ligands of tear lipocalin.

  6. Monopod bucket foundations under cyclic lateral loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo

    on bucket foundations under lateral cyclic loading. The test setup is described in detail and a comprehensive experimental campaign is presented. The foundation is subjected to cyclic overturning moment, cyclic horizontal loading and constant vertical loading, acting on the same plane for thousands...

  7. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... views of bone, they provide little information about muscles, tendons or joints. An MRI may be more useful in identifying bone and joint injuries (e.g., meniscal and ligament tears in the knee, rotator cuff and labrum tears ...

  8. The use of knowledge-based Genetic Algorithm for starting time optimisation in a lot-bucket MRP

    Science.gov (United States)

    Ridwan, Muhammad; Purnomo, Andi

    2016-01-01

    In production planning, Material Requirement Planning (MRP) is usually developed based on time-bucket system, a period in the MRP is representing the time and usually weekly. MRP has been successfully implemented in Make To Stock (MTS) manufacturing, where production activity must be started before customer demand is received. However, to be implemented successfully in Make To Order (MTO) manufacturing, a modification is required on the conventional MRP in order to make it in line with the real situation. In MTO manufacturing, delivery schedule to the customers is defined strictly and must be fulfilled in order to increase customer satisfaction. On the other hand, company prefers to keep constant number of workers, hence production lot size should be constant as well. Since a bucket in conventional MRP system is representing time and usually weekly, hence, strict delivery schedule could not be accommodated. Fortunately, there is a modified time-bucket MRP system, called as lot-bucket MRP system that proposed by Casimir in 1999. In the lot-bucket MRP system, a bucket is representing a lot, and the lot size is preferably constant. The time to finish every lot could be varying depends on due date of lot. Starting time of a lot must be determined so that every lot has reasonable production time. So far there is no formal method to determine optimum starting time in the lot-bucket MRP system. Trial and error process usually used for it but some time, it causes several lots have very short production time and the lot-bucket MRP would be infeasible to be executed. This paper presents the use of Genetic Algorithm (GA) for optimisation of starting time in a lot-bucket MRP system. Even though GA is well known as powerful searching algorithm, however, improvement is still required in order to increase possibility of GA in finding optimum solution in shorter time. A knowledge-based system has been embedded in the proposed GA as the improvement effort, and it is proven that the

  9. The association between reduced knee joint proprioception and medial meniscal abnormalities using MRI in knee osteoarthritis: results from the Amsterdam osteoarthritis cohort.

    Science.gov (United States)

    van der Esch, M; Knoop, J; Hunter, D J; Klein, J-P; van der Leeden, M; Knol, D L; Reiding, D; Voorneman, R E; Gerritsen, M; Roorda, L D; Lems, W F; Dekker, J

    2013-05-01

    Osteoarthritis (OA) of the knee is characterized by pain and activity limitations. In knee OA, proprioceptive accuracy is reduced and might be associated with pain and activity limitations. Although causes of reduced proprioceptive accuracy are divergent, medial meniscal abnormalities, which are highly prevalent in knee OA, have been suggested to play an important role. No study has focussed on the association between proprioceptive accuracy and meniscal abnormalities in knee OA. To explore the association between reduced proprioceptive accuracy and medial meniscal abnormalities in a clinical sample of knee OA subjects. Cross-sectional study in 105 subjects with knee OA. Knee proprioceptive accuracy was assessed by determining the joint motion detection threshold in the knee extension direction. The knee was imaged with a 3.0 T magnetic resonance (MR) scanner. Number of regions with medial meniscal abnormalities and the extent of abnormality in the anterior and posterior horn and body were scored according to the Boston-Leeds Osteoarthritis Knee Score (BLOKS) method. Multiple regression analyzes were used to examine whether reduced proprioceptive accuracy was associated with medial meniscal abnormalities in knee OA subjects. Mean proprioceptive accuracy was 2.9° ± 1.9°. Magnetic resonance imaging (MRI)-detected medial meniscal abnormalities were found in the anterior horn (78%), body (80%) and posterior horn (90%). Reduced proprioceptive accuracy was associated with both the number of regions with meniscal abnormalities (P knee complaints. This is the first study showing that reduced proprioceptive accuracy is associated with medial meniscal abnormalities in knee OA. The study highlights the importance of meniscal abnormalities in understanding reduced proprioceptive accuracy in persons with knee OA. Copyright © 2013 Osteoarthritis Research Society International. All rights reserved.

  10. Estudo artroscópico da articulação do joelho em cães portadores de lesão do ligamento cruzado cranial

    Directory of Open Access Journals (Sweden)

    Angelica Cecilia Tatarunas

    2006-12-01

    Full Text Available The objective of the present study was to report intra articular changes observed by means of arthroscopic in dogs bearing cranial cruciate ligament injuries. Sixty-three dogs (sixty-five knee joints with naturally occurring cranial cruciate injury were used. The arthroscopy was carried out before the ligament repair and the observed changes were both recorded and reported. According to the results obtained from this research it is significant to mention the presence of plicae on suprapatelar joint pouch; roughness, neovascularization and osteophytes in patella. The lateral meniscus presented axial fringe tear, fibrillation, neovascularization and complete laceration. The medial meniscus showed bucket handle tear, complete laceration, axial fringe tear, fibrillation, neovascularization and mineralization. The cranial cruciate ligament was completely ruptured, partially ruptured, interstitially ruptured and linked to the structures of the intercondylar notch. The caudal cruciate ligament showed vertical splits, besides fibrillation and partial rupture. Arthroscopy has been used for diagnostic of cranial cruciate ligament injuries in dogs. It permits improved diagnostic capability when evaluating cartilage and sinovial changes, meniscus and ligaments tears.

  11. Identification of Suitable Reference Genes for Investigating Gene Expression in Anterior Cruciate Ligament Injury by Using Reverse Transcription-Quantitative PCR.

    Directory of Open Access Journals (Sweden)

    Mariana Ferreira Leal

    Full Text Available The anterior cruciate ligament (ACL is one of the most frequently injured structures during high-impact sporting activities. Gene expression analysis may be a useful tool for understanding ACL tears and healing failure. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR has emerged as an effective method for such studies. However, this technique requires the use of suitable reference genes for data normalization. Here, we evaluated the suitability of six reference genes (18S, ACTB, B2M, GAPDH, HPRT1, and TBP by using ACL samples of 39 individuals with ACL tears (20 with isolated ACL tears and 19 with ACL tear and combined meniscal injury and of 13 controls. The stability of the candidate reference genes was determined by using the NormFinder, geNorm, BestKeeper DataAssist, and RefFinder software packages and the comparative ΔCt method. ACTB was the best single reference gene and ACTB+TBP was the best gene pair. The GenEx software showed that the accumulated standard deviation is reduced when a larger number of reference genes is used for gene expression normalization. However, the use of a single reference gene may not be suitable. To identify the optimal combination of reference genes, we evaluated the expression of FN1 and PLOD1. We observed that at least 3 reference genes should be used. ACTB+HPRT1+18S is the best trio for the analyses involving isolated ACL tears and controls. Conversely, ACTB+TBP+18S is the best trio for the analyses involving (1 injured ACL tears and controls, and (2 ACL tears of patients with meniscal tears and controls. Therefore, if the gene expression study aims to compare non-injured ACL, isolated ACL tears and ACL tears from patients with meniscal tear as three independent groups ACTB+TBP+18S+HPRT1 should be used. In conclusion, 3 or more genes should be used as reference genes for analysis of ACL samples of individuals with and without ACL tears.

  12. SABRE: A Sensitive Attribute Bucketization and REdistribution framework for t-closeness

    KAUST Repository

    Cao, Jianneng

    2010-05-19

    Today, the publication of microdata poses a privacy threat: anonymous personal records can be re-identified using third data sources. Past research has tried to develop a concept of privacy guarantee that an anonymized data set should satisfy before publication, culminating in the notion of t-closeness. To satisfy t-closeness, the records in a data set need to be grouped into Equivalence Classes (ECs), such that each EC contains records of indistinguishable quasi-identifier values, and its local distribution of sensitive attribute (SA) values conforms to the global table distribution of SA values. However, despite this progress, previous research has not offered an anonymization algorithm tailored for t-closeness. In this paper, we cover this gap with SABRE, a SA Bucketization and REdistribution framework for t-closeness. SABRE first greedily partitions a table into buckets of similar SA values and then redistributes the tuples of each bucket into dynamically determined ECs. This approach is facilitated by a property of the Earth Mover\\'s Distance (EMD) that we employ as a measure of distribution closeness: If the tuples in an EC are picked proportionally to the sizes of the buckets they hail from, then the EMD of that EC is tightly upper-bounded using localized upper bounds derived for each bucket. We prove that if the t-closeness constraint is properly obeyed during partitioning, then it is obeyed by the derived ECs too. We develop two instantiations of SABRE and extend it to a streaming environment. Our extensive experimental evaluation demonstrates that SABRE achieves information quality superior to schemes that merely applied algorithms tailored for other models to t-closeness, and can be much faster as well. © 2010 Springer-Verlag.

  13. Bucket wheel rehabilitation of ERC 1400-30/7 high-capacity excavators from lignite quarries

    Science.gov (United States)

    Vîlceanu, Fl; Iancu, C.

    2016-11-01

    The existence of bucket wheel equipment type ERC 1400-30/7 in lignite quarries with lifetime expired, or in the ultimate life period, together with high cost investments for their replacement, makes rational the efforts made to rehabilitation in order to extend their life. Rehabilitation involves checking operational safety based on relevant expertise of metal structures supporting effective resistance but also the replacement (or modernization) of subassemblies that can increase excavation process productivity, lowering energy consumption, reducing mechanical stresses. This paper proposes an analysis of constructive solution of using a part of the classical bucket wheel, on which are located 9 cutting cups and 9 chargers cups and adding a new part so that the new redesigned bucket-wheel will contain 18 cutting-chargers cups, compared to the classical model. On the CAD model of bucket wheel was performed a static and a dynamic FEA, the results being compared with the yield strength of the material of the entire structure, were checked mechanical stresses in the overall distribution map, and were verified the first 4 vibrating modes the structure compared to real loads. Thus was verified that the redesigned bucket-wheel can accomplish the proposed goals respectively increase excavation process productivity, lowering energy consumption and reducing mechanical stresses.

  14. A Cohort Study on Meniscal Lesions among Airport Baggage Handlers

    DEFF Research Database (Denmark)

    Mikkelsen, Sigurd; Brauer, Charlotte; Pedersen, Ellen Bøtker

    2016-01-01

    socioeconomic background and less knee-straining work. Baggage handlers lifted suitcases with an average weight of approximately 15 kg, in total approximately five tonnes during a 9-hour workday. The cohort was followed in the National Patient Register and Civil Registration System. The outcome was a first time......Meniscal lesions are common and may contribute to the development of knee arthrosis. A few case-control and cross-sectional studies have identified knee-straining work as risk factors for meniscal lesions, but exposure-response relations and the role of specific exposures are uncertain...... of unskilled men employed at Copenhagen Airport or in other companies in the metropolitan Copenhagen area from 1990 to 2012 (the Copenhagen Airport Cohort). The cohort at risk included 3,307 airport baggage handlers with heavy lifting and kneeling or squatting work tasks and 63,934 referents with a similar...

  15. Human meniscal proteoglycan metabolism in long-term tissue culture

    NARCIS (Netherlands)

    Verbruggen, G.; Verdonk, R.; Veys, E. M.; van Daele, P.; de Smet, P.; van den Abbeele, K.; Claus, B.; Baeten, D.

    1996-01-01

    For the purpose of human meniscal allografting, menisci have been maintained viable in in vitro culture. The influence of long-term tissue culture on the extracellular matrix metabolism of the meniscus has been studied. Fetal calf serum (FCS) was used as a supplement for the growth factors necessary

  16. Meniscectomy versus meniscal repair: 10 years radiological and clinical results in vertical lesions in stable knee.

    Science.gov (United States)

    Lutz, C; Dalmay, F; Ehkirch, F P; Cucurulo, T; Laporte, C; Le Henaff, G; Potel, J F; Pujol, N; Rochcongar, G; Salledechou, E; Seil, R; Gunepin, F-X; Sonnery-Cottet, B

    2015-12-01

    Surgical management of meniscal lesion consists of either a meniscectomy or meniscal repair. Although repair offers immediate recovery after surgery, it is also associated with higher rates of revision. A meniscectomy, on the other hand is known to be associated with an early onset of osteoarthritis. The present study compared clinical and radiological results at 10 years between meniscectomy and meniscal repair in isolated vertical lesion in an otherwise stable knee. The hypothesis was that repair shows functional and radiological benefit over meniscectomy. A multi-centric retrospective comparative study of 32 patients (24 male, 8 female). Mean follow-up was 10.6 years (range, 10-13 years). There were 10 meniscal repairs (group R) and 22 meniscectomies (group M), in 17 right and 15 left knees. Mean age at surgery was 33.45±12.3 years (range, 9-47 years). There were 28 medial and 4 lateral meniscal lesions; 26 were in the red-red zone and 6 in red-white zone. Functional score: KOOS score was significantly higher in group R than M on almost all parameters: 98±4.69 versus 77.38±21.97 for symptoms (P=0.0043), 96.89±7.20 versus 78.57±18.9 for pain (P=0.0052), 99.89±0.33 versus 80.88±19.6 for daily life activities (P=0.0002), 96.11±9.83 versus 54.05±32.85 for sport and leisure (P=0.0005), but 91±16.87 versus 68.15±37.7 for quality of life (P=0.1048). Radiology score: in group R, 7 patients had no features of osteoarthritis, and 2 had grade 1 osteoarthritis. In group M, 5 patients had grade 1 osteoarthritis, 10 grade 2, 3 grade 3 and 3 grade 4. Mean quantitative score was 0 (mean, 0.22±0.44) in-group R and 2 (mean, 2.19±0.98) in group M (P<0.0001). At more than 10year's follow-up, functional scores were significantly better with meniscal repair than meniscectomy on all parameters of the KOOS scale except quality of life. Functional and radiological scores correlated closely. These results show that meniscal repair for vertical lesions in stable knees

  17. Deltoid muscle and tendon tears in patients with chronic rotator cuff tears

    International Nuclear Information System (INIS)

    Ilaslan, Hakan; Recht, Michael P.; Iannotti, Joseph P.

    2007-01-01

    To describe the magnetic resonance imaging (MRI) appearances of tears of the deltoid muscle and tendon in patients with rotator cuff tears and without a prior history of shoulder surgery. Deltoid tears diagnosed on MR examinations were prospectively recorded between February 2003 through June 2004. The images of these patients were then retrospectively reviewed to determine the location of the deltoid tear, the presence of rotator cuff tears, tendon retraction, muscle atrophy, degree of humeral head subluxation, bony erosive changes involving the undersurface of the acromion, and the presence of edema or fluid-like signal intensity in the deltoid muscle and overlying subcutaneous tissues. There were 24 (0.3%) patients with deltoid tears; nine men and 15 women. The age range was 54 to 87 (average 73) years. The right side was involved in 20 cases, and the left in four cases. Fifteen patients had full thickness and nine had partial thickness tears of the deltoid. Shoulder pain was the most common presenting symptom. The physical examination revealed a defect in the region of the deltoid in two patients. Nineteen patients had tears in the muscle belly near the musculotendinous junction, and five had avulsion of the tendon from the acromial origin. Full thickness rotator cuff tears were present in all of the patients, and 22 patients had associated muscle atrophy. Subcutaneous edema and fluid-like signal was present in 15 patients. Tears of the deltoid muscle or tendon is an unusual finding, but they can be seen in patients with chronic massive rotator cuff tears. Partial thickness tears tend to involve the undersurface of the deltoid muscle and tendon. Associated findings such as intramuscular cyst or ganglion in the deltoid muscle belly and subcutaneous edema or fluid-like signal overlying the deltoid in a patient with a rotator cuff tear should raise the suspicion of a deltoid tear. (orig.)

  18. Deltoid muscle and tendon tears in patients with chronic rotator cuff tears

    Energy Technology Data Exchange (ETDEWEB)

    Ilaslan, Hakan; Recht, Michael P. [Cleveland Clinic, Musculoskeletal Radiology/A21, Division of Radiology, Cleveland, OH (United States); Iannotti, Joseph P. [Cleveland Clinic, Department of Orthopedic Surgery, Cleveland, OH (United States)

    2007-06-15

    To describe the magnetic resonance imaging (MRI) appearances of tears of the deltoid muscle and tendon in patients with rotator cuff tears and without a prior history of shoulder surgery. Deltoid tears diagnosed on MR examinations were prospectively recorded between February 2003 through June 2004. The images of these patients were then retrospectively reviewed to determine the location of the deltoid tear, the presence of rotator cuff tears, tendon retraction, muscle atrophy, degree of humeral head subluxation, bony erosive changes involving the undersurface of the acromion, and the presence of edema or fluid-like signal intensity in the deltoid muscle and overlying subcutaneous tissues. There were 24 (0.3%) patients with deltoid tears; nine men and 15 women. The age range was 54 to 87 (average 73) years. The right side was involved in 20 cases, and the left in four cases. Fifteen patients had full thickness and nine had partial thickness tears of the deltoid. Shoulder pain was the most common presenting symptom. The physical examination revealed a defect in the region of the deltoid in two patients. Nineteen patients had tears in the muscle belly near the musculotendinous junction, and five had avulsion of the tendon from the acromial origin. Full thickness rotator cuff tears were present in all of the patients, and 22 patients had associated muscle atrophy. Subcutaneous edema and fluid-like signal was present in 15 patients. Tears of the deltoid muscle or tendon is an unusual finding, but they can be seen in patients with chronic massive rotator cuff tears. Partial thickness tears tend to involve the undersurface of the deltoid muscle and tendon. Associated findings such as intramuscular cyst or ganglion in the deltoid muscle belly and subcutaneous edema or fluid-like signal overlying the deltoid in a patient with a rotator cuff tear should raise the suspicion of a deltoid tear. (orig.)

  19. MRI STUDY OF TYPES AND INCIDENCE OF INTERNAL DERANGEMENTS OF TRAUMATIC KNEE JOINT

    Directory of Open Access Journals (Sweden)

    Bomidi Sudha Rani

    2016-12-01

    Full Text Available BACKGROUND MRI has been accepted as the best imaging modality for noninvasive evaluation of knee injuries and it has proved reliable, safe and offers advantages over diagnostic arthroscopy, which is currently regarded as the reference standard for the diagnosis of internal derangements of the knee. 1 METHODS AND MATERIALS A prospective study of fifty patients who underwent MRI for the diagnosis of internal derangement of knee was conducted between the period of January 2015 to January 2016 in Government General Hospital, Kakinada. All the patients with history of knee joint pain following trauma and clinically suspected to have meniscal and ligament tears are included in the study. Patients were evaluated using GE 1.5 T MRI machine with pulsar gradient system using a sensor extremity coil. RESULTS Commonest lesion detected in our study was ACL tear followed by medial meniscal tear and medial collateral ligament injury. The most common sign of cruciate ligament injury was hyperintensity in the ligament. Grade 3 was the most common grade of meniscal tear. CONCLUSION MRI is an excellent, noninvasive, radiation free imaging modality and is unique in its ability to evaluate the internal structure as well as soft tissue delineation. Many anatomical variants can mimic a tear on MRI. MRI is an excellent noninvasive modality for imaging the knee and helps in arriving at a correct anatomical diagnosis there by guiding further management of the patient.

  20. Tear secretion and tear stability of women on hormonal contraceptives

    Directory of Open Access Journals (Sweden)

    Faustina Kemdinum Idu

    2013-01-01

    Conclusions: Injectable hormonal contraceptives had no significant effects on tear secretion and tear stability of healthy women of childbearing age. Further studies may be required to determine the effects of hormonal contraceptives on tear volume and stability of women with dry eyes.

  1. Cost-Effective Mass Production of Mono Bucket Foundations

    DEFF Research Database (Denmark)

    Gres, Szymon; Nielsen, Søren Andreas; Fejerskov, Morten

    2015-01-01

    for innovative and cost-effective design of Mono Bucket foundations. Established approach merges wind and wave load models, soil/structure interaction topics, structural optimization and installation/fabrication aspects, into software package with ability to perform optimal design of the individual foundations...

  2. Literature review on cyclic lateral loading effects of mono-bucket foundations

    DEFF Research Database (Denmark)

    Kapitanov, Lachezar Rosenov; Duroska, Peter; Quirante, Cesar Antonio Garcia

    2016-01-01

    and consequently cost-effectiveness compared to other common solutions. The long-term cyclic loading can cause degradation of soil-bucket system stiffness, which yields into accumulated and permanent deformations. Despite of the advantages, there is no standard procedure to design the foundation especially...... calculation is highly demanded at the different design phases. The intention of the current study is to present, review and summarize the existing techniques to assess the effect of cyclic loading on Mono-Bucket foundations while emphasizing the advantage and disadvantage of each of them. Additionally...

  3. A comparison of basal and eye-flush tears for the analysis of cat tear proteins.

    Science.gov (United States)

    Petznick, Andrea; Evans, Margaret D M; Madigan, Michele C; Markoulli, Maria; Garrett, Qian; Sweeney, Deborah F

    2011-02-01

    To identify a rapid and effective tear collection method providing sufficient tear volume and total protein content (TPC) for analysis of individual proteins in cats. Domestic adult short-haired cats (12-37 months; 2.7-6.6 kg) were used in the study. Basal tears without stimulation and eye-flush tears after instillation of saline (10 μl) were collected using microcapillary tubes from animal eyes either unwounded control or wounded with 9-mm central epithelial debridement giving four groups with n = 3. Tear comparisons were based on total time and rate for tear collection, TPC using micro bicinchoninic acid (BCA), tear immunoglobulin A (IgA), total matrix-metalloproteinase (MMP)-9 concentration using sandwich enzyme-linked immunosorbent assay (ELISA) and MMP-9 activity. Eye-flush tears were collected significantly faster than basal tears in wounded eyes with higher rates for tear collection in unwounded control and wounded eyes. TPC was significantly lower in eye-flush tears compared to basal tears. The relative proportion of tear IgA normalized to TPC (% IgA of TPC) was not significantly different between basal and eye-flush tears. In unwounded control eyes, MMP-9 was slightly higher in eye-flush than in basal tears; activity of MMP-9 in both tear types was similar. In wounded eyes, eye-flush tears showed highest MMP-9 levels and activity on Day 1, which subsequently decreased to Day 7. MMP-9 activity in basal tears from wounded eyes did not display changes in expression. Eye-flush tears can be collected rapidly providing sufficient tear volume and TPC. This study also indicates that eye-flush tears may be more suitable than basal tears for the analysis of MMPs following corneal wounding. © 2011 The Authors. Acta Ophthalmologica © 2011 Acta Ophthalmologica Scandinavica Foundation.

  4. What is the best way to fix a polyurethane meniscal scaffold? A biomechanical evaluation of different fixation modes.

    Science.gov (United States)

    Hardeman, Francois; Corten, Kristoff; Mylle, Michiel; Van Herck, Bert; Verdonk, René; Verdonk, Peter; Bellemans, Johan

    2015-01-01

    Ingrowth of meniscal tissue into a meniscal scaffold can be optimized by securely fixing the scaffold into the meniscal remnants. The purpose of this research was to test and compare commonly used suture types and suture materials to fix a meniscal scaffold. Forty fresh porcine menisci were used. All tests used the same polyurethane-based scaffold. The load to failure of horizontal, vertical and diagonal sutures with PDS 0 and with Ethibond 0, and diagonal sutures with Ultra Fast-Fix(®) and Sequent(®) to fix a meniscal scaffold were tested. Five tests were conducted for each configuration. All constructs failed in the scaffold at a mean pullout force of 50.6 N (SD 12.7). Inferior results were noted for vertical sutures (40.1 N, SD 6.3) compared to horizontal (49.8 N, SD 5.5, p = 0.0007) and diagonal (51.7 N, SD 15.6, p = 0.024) sutures and for Ethibond 0 (41.4 N, SD 6.2) compared to PDS 0 (51.3 N, SD 12.9, p = 0.001). When comparing the diagonal suture placements, only Ethibond 0 (42.9 N, SD 5.4) showed significantly inferior results compared to PDS 0 (60.1 N, SD 16.9, p = 0.03), Ultra Fast-Fix(®) (60.1 N, SD 9.3, p = 0.004) and Sequent(®) (65.8 N, SD 4.4, p < 0.0001). The most common failure mode when fixing a polyurethane-based meniscal scaffold is suture pull-through of the scaffold in the distraction mode. This happens at a rather low pullout force and might preclude the use of this scaffold clinically. Vertical sutures and Ethibond 0 multifilament braided sutures fail at lower forces, and the tested commercial devices show promising results.

  5. Comparison of osmotic swelling influences on meniscal fibrocartilage and articular cartilage tissue mechanics in compression and shear.

    Science.gov (United States)

    Nguyen, An M; Levenston, Marc E

    2012-01-01

    Although the contribution of the circumferential collagen bundles to the anisotropic tensile stiffness of meniscal tissue has been well described, the implications of interactions between tissue components for other mechanical properties have not been as widely examined. This study compared the effects of the proteoglycan-associated osmotic swelling stress on meniscal fibrocartilage and articular cartilage (AC) mechanics by manipulating the osmotic environment and tissue compressive offset. Cylindrical samples were obtained from the menisci and AC of bovine stifles, equilibrated in phosphate-buffered saline solutions ranging from 0.1× to 10×, and tested in oscillatory torsional shear and unconfined compression. Biochemical analysis indicated that treatments and testing did not substantially alter tissue composition. Mechanical testing revealed tissue-specific responses to both increasing compressive offset and decreasing bath salinity. Most notably, reduced salinity dramatically increased the shear modulus of both axially and circumferentially oriented meniscal tissue explants to a much greater extent than for cartilage samples. Combined with previous studies, these findings suggest that meniscal proteoglycans have a distinct structural role, stabilizing, and stiffening the matrix surrounding the primary circumferential collagen bundles. Copyright © 2011 Orthopaedic Research Society.

  6. Performance of PROMIS for Healthy Patients Undergoing Meniscal Surgery.

    Science.gov (United States)

    Hancock, Kyle J; Glass, Natalie; Anthony, Chris A; Hettrich, Carolyn M; Albright, John; Amendola, Annunziato; Wolf, Brian R; Bollier, Matthew

    2017-06-07

    The Patient-Reported Outcomes Measurement Information System (PROMIS) was developed as an extensive question bank with multiple health domains that could be utilized for computerized adaptive testing (CAT). In the present study, we investigated the use of the PROMIS Physical Function CAT (PROMIS PF CAT) in an otherwise healthy population scheduled to undergo surgery for meniscal injury with the hypotheses that (1) the PROMIS PF CAT would correlate strongly with patient-reported outcome instruments that measure physical function and would not correlate strongly with those that measure other health domains, (2) there would be no ceiling effects, and (3) the test burden would be significantly less than that of the traditional measures. Patients scheduled to undergo meniscal surgery completed the PROMIS PF CAT, Knee injury and Osteoarthritis Outcome Score (KOOS), Marx Knee Activity Rating Scale, Short Form-36 (SF-36), and EuroQol-5 Dimension (EQ-5D) questionnaires. Correlations were defined as high (≥0.7), high-moderate (0.61 to 0.69), moderate (0.4 to 0.6), moderate-weak (0.31 to 0.39), or weak (≤0.3). If ≥15% respondents to a patient-reported outcome measure obtained the highest or lowest possible score, the instrument was determined to have a significant ceiling or floor effect. A total of 107 participants were analyzed. The PROMIS PF CAT had a high correlation with the SF-36 Physical Functioning (PF) (r = 0.82, p ceiling effects, with 0% of the participants achieving the lowest and highest score, respectively. The PROMIS PF CAT correlates strongly with currently used patient-reported outcome measures of physical function and demonstrates no ceiling effects for patients with meniscal injury requiring surgery. It may be a reasonable alternative to more burdensome patient-reported outcome measures.

  7. Consideration on the 1 ton bucket elevator installed under water of pool in IMEF

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ung Sup; Lee, Jong Heon; Lee, Hong Gi; Choo, Yong Sun; Jung, Yang Hong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2004-07-01

    The bucket elevator which can transfer examination capsule or fuel from pool to hot cell is installed under water of pool (3x6x10 m) in IMEF. A allowable load is 1 ton and the dimension of bucket is 25x25x150 cm. The upper and lower sides motion of bucket have about 63 degrees inclined duties with a chain driving system. A specialized made chain catches a rug of bucket with a roller sliding way between right and left guide rails which are fixed at inner of a square tube and moves to an upper and lower sides and it is made so that it is operated by sprocket wheel installed in a hot cell working table below. Sprocket wheel is executed to two steps of driving shaft by reduction geared motor installed at right outside of M1 hot cell. As for the starting operation, it is executed by push an operation button on a operating panel located at front of M1 hot cell.

  8. Blocked Tear Duct

    Science.gov (United States)

    ... of the nose (lacrimal sac). From there tears travel down a duct (the nasolacrimal duct) draining into your nose. Once in the nose, tears are reabsorbed. A blockage can occur at any point in the tear drainage system, from the puncta ...

  9. Laboratory experiments of bucket foundations under cyclic loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo

    This report collects information on the experimental campaign concerning bucket foundations under lateral cyclic loading conducted by the authors between 2011 and 2014. The report includes a step by step manual on the test procedures and a number of information and graphs for each experiment...

  10. Vertical Capacity of Bucket Foundations in Undrained Soil

    DEFF Research Database (Denmark)

    Barari, Amin; Ibsen, Lars Bo

    2014-01-01

    Offshore wind turbine structures are traditionally founded on gravity concrete foundations or mono-piles. Bucket foundations were developed for the offshore oil and gas industry and are now being used in wind turbine construction. The loading in this application is characterized by a vertical loa...

  11. Tear-Film Evaporation Rate from Simultaneous Ocular-Surface Temperature and Tear-Breakup Area.

    Science.gov (United States)

    Dursch, Thomas J; Li, Wing; Taraz, Baseem; Lin, Meng C; Radke, Clayton J

    2018-01-01

    A corneal heat-transfer model is presented to quantify simultaneous measurements of fluorescein tear-breakup area (TBA) and ocular-surface temperature (OST). By accounting for disruption of the tear-film lipid layer (TFLL), we report evaporation rates through lipid-covered tear. The modified heat-transfer model provides new insights into evaporative dry eye. A quantitative analysis is presented to assess human aqueous tear evaporation rate (TER) through intact TFLLs from simultaneous in vivo measurement of time-dependent infrared OST and fluorescein TBA. We interpret simultaneous OST and TBA measurements using an extended heat-transfer model. We hypothesize that TBAs are ineffectively insulated by the TFLL and therefore exhibit higher TER than does that for a well-insulting TFLL-covered tear. As time proceeds, TBAs increase in number and size, thereby increasing the cornea area-averaged TER and decreasing OST. Tear-breakup areas were assessed from image analysis of fluorescein tear-film-breakup video recordings and are included in the heat-transfer description of OST. Model-predicted OSTs agree well with clinical experiments. Percent reductions in TER of lipid-covered tear range from 50 to 95% of that for pure water, in good agreement with literature. The physical picture of noninsulating or ruptured TFLL spots followed by enhanced evaporation from underlying cooler tear-film ruptures is consistent with the evaporative-driven mechanism for local tear rupture. A quantitative analysis is presented of in vivo TER from simultaneous clinical measurement of transient OST and TBA. The new heat-transfer model accounts for increased TER through expanding TBAs. Tear evaporation rate varies strongly across the cornea because lipid is effectively missing over tear-rupture troughs. The result is local faster evaporation compared with nonruptured, thick lipid-covered tear. Evaporative-driven tear-film ruptures deepen to a thickness where fluorescein quenching commences and local

  12. Optimization of the Water Volume in the Buckets of Pico Hydro Overshot Waterwheel by Analytical Method

    Science.gov (United States)

    Budiarso; Adanta, Dendy; Warjito; Siswantara, A. I.; Saputra, Pradhana; Dianofitra, Reza

    2018-03-01

    Rapid economic and population growth in Indonesia lead to increased energy consumption, including electricity needs. Pico hydro is considered as the right solution because the cost of investment and operational cost are fairly low. Additionally, Indonesia has many remote areas with high hydro-energy potential. The overshot waterwheel is one of technology that is suitable to be applied in remote areas due to ease of operation and maintenance. This study attempts to optimize bucket dimensions with the available conditions. In addition, the optimization also has a good impact on the amount of generated power because all available energy is utilized maximally. Analytical method is used to evaluate the volume of water contained in bucket overshot waterwheel. In general, there are two stages performed. First, calculation of the volume of water contained in each active bucket is done. If the amount total of water contained is less than the available discharge in active bucket, recalculation at the width of the wheel is done. Second, calculation of the torque of each active bucket is done to determine the power output. As the result, the mechanical power generated from the waterwheel is 305 Watts with the efficiency value of 28%.

  13. The role of meniscal tissue in joint protection in early osteoarthritis.

    Science.gov (United States)

    Verdonk, Rene; Madry, Henning; Shabshin, Nogah; Dirisamer, Florian; Peretti, Giuseppe M; Pujol, Nicolas; Spalding, Tim; Verdonk, Peter; Seil, Romain; Condello, Vincenzo; Di Matteo, Berardo; Zellner, Johannes; Angele, Peter

    2016-06-01

    It is widely accepted that partial meniscectomy leads to early onset of osteoarthritis (OA). A strong correlation exists between the amount and location of the resected meniscus and the development of degenerative changes in the knee. On the other hand, osteoarthritic changes of the joint alter the structural and functional integrity of meniscal tissue. These alterations might additionally compromise the limited healing capacity of the meniscus. In young, active patients without cartilage damage, meniscus therapy including partial meniscectomy, meniscus suture, and meniscus replacement has proven beneficial effects in long-term studies. Even in an early osteoarthritic milieu, there is a relevant regenerative potential of the meniscus and the surrounding cartilage. This potential should be taken into account, and meniscal surgery can be performed with the correct timing and the proper indication even in the presence of early OA.

  14. On-land and offshore testing of a new helicopter bucket for dispersant application - response 3000D

    International Nuclear Information System (INIS)

    Brandvik, P. J.; Lewis, A.; Daling, P. S.; Strom-Kristiansen, T.; Larsen, E.

    1997-01-01

    Development of a new helicopter bucket for dispersant applications to serve the dispersant spraying needs of Norwegian oil companies was described. Testing two existing helicopter buckets and practical experience with firefighting helicopter operations provided the foundations for this developmental experiment, combined with the dispersant applications experience of SINTEF. The newly designed bucket, 3000D, has two dispersant spray systems (high and low flow rates) and a large capacity ( three cu m). It is capable of direct filling of dispersant via a suction hose while the helicopter is hovering and is equipped for remote control of all functions. It is robustly designed for use under harsh offshore conditions in the North Sea. The bucket has been subjected to extensive testing on land and offshore with experimental oil slicks. The results were fully satisfactory. 9 refs., 1 tab., 13 figs

  15. Implantation of autogenous meniscal fragments wrapped with a fascia sheath enhances fibrocartilage regeneration in vivo in a large harvest site defect.

    Science.gov (United States)

    Kobayashi, Yasukazu; Yasuda, Kazunori; Kondo, Eiji; Katsura, Taro; Tanabe, Yoshie; Kimura, Masashi; Tohyama, Harukazu

    2010-04-01

    Concerning meniscal tissue regeneration, many investigators have studied the development of a tissue-engineered meniscus. However, the utility still remains unknown. Implantation of autogenous meniscal fragments wrapped with a fascia sheath into the donor site meniscal defect may significantly enhance fibrocartilage regeneration in vivo in the defect. Controlled laboratory study. Seventy-five mature rabbits were used in this study. In each animal, an anterior one-third of the right medial meniscus was resected. Then, the animals were divided into the following 3 groups of 25 rabbits each: In group 1, no treatment was applied to the meniscal defect. In group 2, the defect was covered with a fascia sheath. In group 3, after the resected meniscus was fragmented into small pieces, the fragments were grafted into the defect. Then, the defect with the meniscal fragments was covered with a fascia sheath. In each group, 5 rabbits were used for histological evaluation at 3, 6, and 12 weeks after surgery, and 5 rabbits were used for biomechanical evaluation at 6 and 12 weeks after surgery. Histologically, large round cells in group 3 were scattered in the core portion of the meniscus-shaped tissue, and the matrix around these cells was positively stained by safranin O and toluisin blue at 12 weeks. The histological score of group 3 was significantly higher than that of group 1 and group 2. Biomechanically, the maximal load and stiffness of group 3 were significantly greater than those of groups 1 and 2. This study clearly demonstrated that implantation of autogenous meniscal fragments wrapped with a fascia sheath into the donor site meniscal defect significantly enhanced fibrocartilage regeneration in vivo in the defect at 12 weeks after implantation in the rabbit. This study proposed a novel strategy to treat a large defect after a meniscectomy.

  16. Anterior cruciate ligament and meniscal injuries in sports: incidence, time of practice until injury, and limitations caused after trauma.

    Science.gov (United States)

    Astur, Diego Costa; Xerez, Marcos; Rozas, João; Debieux, Pedro Vargas; Franciozi, Carlos Eduardo; Cohen, Moises

    2016-01-01

    To analyze the incidence of ACL and meniscal injuries in a population of recreational and elite athletes from Brazil and the relation of these injuries with their sports activities. This was a prospective observational study of 240 patients with ACL and/or meniscal injuries submitted to surgical treatment. Data of patients and sport modality, as well as Tegner score were registered in the first clinical evaluation. The patients were divided into three groups: (1) isolated rupture of the ACL; (2) ACL injury associated with meniscal injury; (3) isolated menisci injury. The majority of the patients belonged to group 1 (44.58%), followed by group 2 (30.2%) and 3 (25%). Most patients were soccer players. The mean time from sport practice to injury in group 1 was 17.81 years. In group 2, it was 17.3 years, and in group 3, 26.91 years. Soccer athletes presented ACL injury in 0.523/1000 h of practice and meniscal injury in 0.448/1000 h of practice. Before the injury, the mean Tegner score obtained for groups 1, 2, and 3 were 7.18, 7.34, and 6.53, respectively. After knee injury, those values were 3.07, 3.18, and 2.87, respectively. Soccer was the sport that caused the majority of lesions, regardless the group. Furthermore, patients from groups 1 and 2 had less time of practice prior to the injury (17.81 and 17.3 years) than the patients of group 3 (26.91 years). Women presented a higher risk to develop ACL and meniscal injuries in 1000 h of game/practice. Running, volleyball, and weightlifting are in ascending order of risk for ACL and/or meniscal injury. Regarding the return to sport practice, the efficiency of all athletes was impaired because of the injury.

  17. Anterior cruciate ligament and meniscal injuries in sports: incidence, time of practice until injury, and limitations caused after trauma

    Directory of Open Access Journals (Sweden)

    Diego Costa Astur

    Full Text Available ABSTRACT OBJECTIVE: To analyze the incidence of ACL and meniscal injuries in a population of recreational and elite athletes from Brazil and the relation of these injuries with their sports activities. METHODS: This was a prospective observational study of 240 patients with ACL and/or meniscal injuries submitted to surgical treatment. Data of patients and sport modality, as well as Tegner score were registered in the first clinical evaluation. The patients were divided into three groups: (1 isolated rupture of the ACL; (2 ACL injury associated with meniscal injury; (3 isolated menisci injury. RESULTS: The majority of the patients belonged to group 1 (44.58%, followed by group 2 (30.2% and 3 (25%. Most patients were soccer players. The mean time from sport practice to injury in group 1 was 17.81 years. In group 2, it was 17.3 years, and in group 3, 26.91 years. Soccer athletes presented ACL injury in 0.523/1000 h of practice and meniscal injury in 0.448/1000 h of practice. Before the injury, the mean Tegner score obtained for groups 1, 2, and 3 were 7.18, 7.34, and 6.53, respectively. After knee injury, those values were 3.07, 3.18, and 2.87, respectively. CONCLUSION: Soccer was the sport that caused the majority of lesions, regardless the group. Furthermore, patients from groups 1 and 2 had less time of practice prior to the injury (17.81 and 17.3 years than the patients of group 3 (26.91 years. Women presented a higher risk to develop ACL and meniscal injuries in 1000 h of game/practice. Running, volleyball, and weightlifting are in ascending order of risk for ACL and/or meniscal injury. Regarding the return to sport practice, the efficiency of all athletes was impaired because of the injury.

  18. Usefulness of meniscal width to transverse diameter ratio on coronal MRI in the diagnosis of incomplete discoid lateral meniscus

    International Nuclear Information System (INIS)

    Park, H.J.; Lee, S.Y.; Park, N.-H.; Chung, E.C.; Park, J.Y.; Kim, M.S.; Lee, E.J.

    2014-01-01

    Aim: To evaluate the clinical utility of the meniscal width to transverse diameter ratio (L/M ratio) of the lateral meniscus in the diagnosis of incomplete discoid lateral meniscus (IDLM) as compared with the arthroscopic diagnosis, meniscal width to tibial diameter ratio (L/T ratio) and conventional lateral meniscus width criteria. Materials and methods: This retrospective study sample included 41 patients with IDLM who underwent knee magnetic resonance imaging (MRI) and arthroscopy, as well as 50 controls with normal lateral menisci. MRI examinations were interpreted independently by two radiologists, both of whom were blinded to clinical information and radiological reports. Assessment of meniscal width (L), maximal transverse diameter of the lateral meniscus (M), and transverse diameter of the tibia (T) was carried out on central coronal sections that were observed to pass through the medial collateral ligament. L/M and L/T ratios were calculated. These results were correlated with arthroscopic findings and analysed statistically using categorical regression analysis and non-parametric correlation analysis. Using arthroscopic findings as the standard of reference, sensitivity and specificity were calculated for: (1) 12, 13, 14, and 15 mm meniscal width thresholds; (2) 40%, 50%, 60%, and 70% L/M ratio thresholds; and (3) 15%, 18%, 20%, and 25% L/T ratio thresholds. Results: The mean L/M ratio of the IDLM was approximately 67% and was statistically significantly higher than the control (44%). The best diagnostic discrimination was achieved using a threshold of 50%. The mean L/T ratio of the IDLM was approximately 23% and was statistically significant. The best diagnostic discrimination was achieved using a threshold of 18%. The threshold of 13 mm of meniscal width also showed high sensitivity and high specificity. Conclusion: The use of the L/M ratio or L/T ratio in combination with meniscal width criteria may be a useful method for evaluating IDLM

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... be more useful in identifying bone and joint injuries (e.g., meniscal and ligament tears in the knee, rotator cuff and labrum tears in the shoulder) and in imaging of the spine (because both the bones and the spinal cord can be evaluated). MRI can also detect subtle ...

  20. Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells

    Science.gov (United States)

    2017-11-01

    meniscal findings on knee MRI in middle-aged and elderly persons. N. Engl. J. Med. 359, 1108–1115.802 Stem Cell Reports j Vol. 3 j 789–803 j November 11...PBS, pH¼7.4) with protease inhibitors (Pierce Protease Inhibitor Tablets 88266, Thermo Fisher Scientific, Rockford, IL) at 4 1C for less than 24 h

  1. Value of Fat-Suppressed Proton-Density-Weighted Turbo Spin-Echo Sequences in Detecting Meniscal Lesions: Comparison with Arthroscopy

    International Nuclear Information System (INIS)

    Schaefer, F.K.W.; Schaefer, P.J.; Brossmann, J.; Frahm, C.; Hilgert, R.E.; Heller, M.; Jahnke, T.

    2006-01-01

    Purpose: To evaluate fat-suppressed (FS) proton-density-weighted (PDw) turbo spin-echo (TSE) magnetic resonance imaging (MRI) compared to arthroscopy in the detection of meniscal lesions. Material and Methods: In a prospective study, 31 knee joints were imaged on a 1.5T MR scanner before arthroscopy using the following sequences: (a) coronal and sagittal FS-PDw TSE (TR/TE: 4009/15 ms); (b) coronal T1w SE (TR/TE: 722/20 ms), and sagittal PDw TSE (TR/TE: 3800/15 ms). Other imaging parameters were: slice thickness 3 mm, FOV 160 mm, matrix 256x256. A total of 186 meniscal regions (62 menisci; anterior horn, body, posterior horn) were evaluated. Standard of reference was arthroscopy. Sensitivity, specificity, negative predictive value (npv), positive predictive value (ppv), and accuracy were calculated. Results: Arthroscopically, meniscal lesions were detected in 55/186 segments (35 medial and 20 lateral meniscal lesions). Sensitivity, specificity, npv, ppv, and accuracy for combination of coronal and sagittal FS PDw TSE were 91.4%, 98.3%, 95%, 97%, and 93.5% for the medial meniscus, and 90%, 98.6%, 97.3%, 94.7%, and 96.8% for the lateral. The results were comparable to the combination of coronal T1w SE and sagittal PDw TSE for the medial (88.6%, 98.3%, 93.4%, 96.9%, 91.4%) and the lateral (90%, 95.9%, 97.2%, 85.7%, 92.5%) meniscus. Conclusion: FS PDw TSE-MR sequences are an excellent alternative for the detection of meniscal lesions in comparison with diagnostic arthroscopy

  2. Tearing instabilities in turbulence

    International Nuclear Information System (INIS)

    Ishizawa, A.; Nakajima, N.

    2009-01-01

    Full text: Effects of micro-turbulence on tearing instabilities are investigated by numerically solving a reduced set of two-fluid equations. Micro-turbulence excites both large-scale and small-scale Fourier modes through energy transfer due to nonlinear mode coupling. The energy transfer to large scale mode does not directly excite tearing instability but it gives an initiation of tearing instability. When tearing instability starts to grow, the excited small scale mode plays an important role. The mixing of magnetic flux by micro-turbulence is the dominant factor of non-ideal MHD effect at the resonant surface and it gives rise to magnetic reconnection which causes tearing instability. Tearing instabilities were investigated against static equilibrium or flowing equilibrium so far. On the other hand, the recent progress of computer power allows us to investigate interactions between turbulence and coherent modes such as tearing instabilities in magnetically confined plasmas by means of direct numerical simulations. In order to investigate effects of turbulence on tearing instabilities we consider a situation that tearing mode is destabilized in a quasi-equilibrium including micro-turbulence. We choose an initial equilibrium that is unstable against kinetic ballooning modes and tearing instabilities. Tearing instabilities are current driven modes and thus they are unstable for large scale Fourier modes. On the other hand kinetic ballooning modes are unstable for poloidal Fourier modes that are characterized by ion Larmor radius. The energy of kinetic ballooning modes spreads over wave number space through nonlinear Fourier mode coupling. We present that micro-turbulence affects tearing instabilities in two different ways by three-dimensional numerical simulation of a reduced set of two-fluid equations. One is caused by energy transfer to large scale modes, the other is caused by energy transfer to small scale modes. The former is the excitation of initial

  3. A Prototype Bucket Wheel Excavator for the Moon, Mars and Phobos

    Science.gov (United States)

    Muff, T.; Johnson, L.; King, R.; Duke, M. B.

    2004-02-01

    Excavation of surface regolith material is the first step in processes to extract volatile materials from planetary surface regolith for the production of propellant and life support consumables. Typically, concentrations of volatiles are low, so relatively large amounts of material must be excavated. A bucket wheel excavator is proposed, which has the capability of continuous excavation, which is readily adapted to granular regolith materials as found on the Moon, in drift deposits on Mars, and probably on the surface of asteroids and satellites, such as Phobos. The bucket wheel excavator is relatively simple, compared to machines such as front end loaders. It also has the advantage that excavation forces are principally horizontal rather than vertical, which minimizes the need for excavator mass and suits it to operations in reduced gravity fields. A prototype small bucket wheel excavator has been built at approximately the scale of the rovers that are carried to Mars on the Mars Exploration Rover Mission. The prototype allows the collection of data on forces exerted and power requirements for excavation and will provide data on which more efficient designs can be based. At excavation rates in the vicinity of one rover mass of material excavated per hour, tests of the prototype demonstrate that the power required is largely that needed to operate the excavator hardware and not related strongly to the amount of material excavated. This suggests that the excavation rate can be much larger for the same excavation system mass. Work on this prototype is continuing on the details of transfer of material from the bucket wheel to an internal conveyor mechanism, which testing demonstrated to be problematic in the current design.

  4. Divalent cations in tears, and their influence on tear film stability in humans and rabbits.

    Science.gov (United States)

    Wei, Xiaojia Eric; Markoulli, Maria; Millar, Thomas J; Willcox, Mark D P; Zhao, Zhenjun

    2012-06-05

    Reduced tear film stability is reported to contribute to dry eye. Rabbits are known to have a more stable tear film than humans. Thus, we sought to examine the tears of rabbits and humans for metal cations, and to test how they influence tear film stability. Tears were collected from 10 healthy humans and 6 rabbits. Tear osmolality was measured by vapor pressure osmometer, and metals analyzed using inductively coupled plasma (ICP) mass spectrometry or ICP atomic emission spectroscopy. The influence of divalent cations on tears was analyzed by measuring surface tension using the Langmuir trough in vitro, using different concentrations of cations in the subphase, and grading the tear break-up in rabbits in vivo after instillation of chelating agents. Rabbit tears had a higher osmolality compared to humans. Major metals did not differ between species; however, rabbits had higher levels of Mg(2+) (1.13 vs. 0.39 mM) and Ca(2+) (0.75 vs. 0.36 mM). In rabbit tears in vitro, diminishing divalent cations resulted in a decrease in the maximum surface pressure from 37 to 30 mN/m. In vivo, an increase in the amount of tear film that was broken-up was found. In contrast, when changing divalent cation concentrations in human tears, the maximum surface pressure remained at 26 mN/m. The normal osmolality of rabbit tears is significantly higher than that in humans. While divalent cations had little influence on human tears, they appear to have an important role in maintaining tear film stability in rabbits.

  5. An RF cavity for barrier bucket experiment in the AGS

    Energy Technology Data Exchange (ETDEWEB)

    Fujieda, M.; Iwashita, Y. [Kyoto Univ. (Japan); Mori, Y. [and others

    1998-11-01

    A barrier bucket experiment in the AGS is planed in 1998. An accumulation of the beam, which intensity of 1.0 x 10{sup 14}ppp is, acceleration after the injection with a barrier bucket scheme and other RF gymnastics experiments will be studied. An isolated RF pulse of 40 kV per cavity is necessary for the experiment. The RF frequency is 2 MHz and the isolated pulse is generated at the repetition rate of the revolution frequency of 357 kHz. We have developed the barrier cavity for this experiment. The cavity is loaded with FINEMET core. It has low Q value but high shunt impedance. It makes the necessary power less than that of ferrite-loaded cavity for an isolated RF pulse. (author)

  6. CAD-based strength analysis of EK-18 excavator bucket construction for mounting of anti-adhesive devices

    Science.gov (United States)

    Zenkov, S. A.; Lobanov, D. V.

    2018-03-01

    3D rigid-body model of a bucket of power shovel EK-18 was built using modern CAD-software. Tetrahedral grid with 10-node second-order elements was chosen, and the given model was imported to APM WinMachine - model preparation preprocessor for finite element analysis. The finite element model was based on the geometrical model, imported from KOMPAS-3D to APM Studio. Calculation of stressed-strained state of the bucket was carried out under the forces emerging while digging with “back hoe” equipment. Shift, deformation and tension charts were planned and the most and the least strained areas were pointed out. Wet coherent soil excavation deals with soil adhesion to working bodies of power shovels and leads to reduced performance. The performance decrease is caused by a reduction of useful bucket capacity and partial unloading, increased front resistance to cutting (digging) caused by wet soil adhesion to a working body, increased bucket entry resistance, increased idle time caused by necessity to clean working bodies. Also energy losses increase and quality of work drops because friction forces go up. Friction force occurs while digging and levelling account for 30…70 percent of total digging resistance while performance decreases 1.2…2 times and more. Vibrothermal exposure creates new technological effect which involves a wider humidity range of efficient application and a reduction of friction forces. Disintegrating adhesion bonds with heating requires less driving force from the vibrator. Vibration boosts up heating of the contact layer, which reduces thermal energy losses. However, the question of piezoelectric ceramic actuators location on the excavator bucket needs to be dealt with. The most suitable spots for mounting piezoelectric ceramic devices for reducing soil adhesion to the excavator bucket were defined. Their efficiency is derived from combined (vibrothermal) methods of exposure. Such devices eliminates soil adhesion to the bucket and increases

  7. Tensile strength of the pullout repair technique for the medial meniscus posterior root tear: a porcine study.

    Science.gov (United States)

    Fujii, Masataka; Furumatsu, Takayuki; Xue, Haowei; Miyazawa, Shinichi; Kodama, Yuya; Hino, Tomohito; Kamatsuki, Yusuke; Ozaki, Toshifumi

    2017-10-01

    The purpose of this study was to compare the load-to-failure of different common suturing techniques with a new technique for the medial meniscus posterior root tear (MMPRT). Thirty porcine medial menisci were randomly assigned to three suturing techniques used for transtibial pullout repair of the MMPRT (n = 10 per group). Three different meniscal suture configurations were studied: the two simple suture (TSS) technique, the conventional modified Mason-Allen suture (MMA) technique, and the new MMA technique using the FasT-Fix combined with the Ultrabraid (F-MMA). The ultimate failure load was tested using a tensile testing machine. The MMA and F-MMA groups demonstrated significantly higher failure loads than the TSS group (P = 0.0003 and P = 0.0005, respectively). No significant differences were observed between the MMA and F-MMA groups (P = 0.734). The ultimate failure load was significantly greater in the F-MMA than the TSS group and similar to the conventional MMA technique.

  8. Kicking the Bucket: It's All about Living

    Science.gov (United States)

    Perry, Kekailoa

    2013-01-01

    In Hawai'i there is a myth known as the alamihi crab syndrome. The myth is a creation of foreign origin used to explain a Western worldview of Hawaiians. It is deployed to explain everything from the 1893 overthrow of the monarchy to the reason why Hawaiians can never better their lives. Crabs in a bucket have a tendency to struggle and fight to…

  9. Bucket Brigades to Increase Productivity in a Luxury Assembly Line

    Directory of Open Access Journals (Sweden)

    Filippo De Carlo

    2013-08-01

    Full Text Available One of the most challenging issues in manual assembly lines is to achieve the best balance of workloads. There are many analytic approaches to solve this problem, but they are often neglected, since they are time-consuming and require high level engineering skills. Fashion bags packaging lines must comply with a number of different products with low production volumes, while the organization of the line is often under the mere responsibility of the foreman, who balances workloads in an empirical way. The aim of this work is to evaluate the effectiveness of the arrangement of bucket brigades (BBs for an assembly line of luxury handbags. To do this, it was decided to perform a testing activity in a company producing fashion handbags in order to compare the self-made design with the BBs and with a simple assembly line balancing problem algorithm. The originality of this research lies in the fact that there are no studies in the literature on BBs applied to the packaging of highly variable small batches. The results were excellent, showing the advantages of BBs in terms of flexibility, the reduction of work in the process and the ability to handle small anomalies.

  10. Meniscus Tears (For Teens)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Meniscus Tears KidsHealth / For Teens / Meniscus Tears What's in this ... surgery to fix it. What Is a Meniscus Tear? Your knee is made up of three bones: ...

  11. [Rotator cuff tear athropathy prevalence].

    Science.gov (United States)

    Guerra-Soriano, F; Encalada-Díaz, M I; Ruiz-Suárez, M; Valero-González, F S

    2017-01-01

    Glenohumeral arthritis secondary to massive rotator cuff tear presents with a superior displacement and femoralization of the humeral head with coracoacromial arch acetabularization. The purpose of this study was to establish prevalence of rotator cuff tear artropathy (CTA) at our institution. Four hundred electronic records were reviewed from which we identified 136 patients with rotator cuff tears. A second group was composed with patients with massive cuff tears that were analized and staged by the Seebauer cuff tear arthropathy classification. Thirty four patients with massive rotator cuff tears were identified, 8 male and 26 female (age 60.1 ± 10.26 years). Massive rotator cuff tear prevalence was 25%. CTA prevalence found in the rotator cuff group was 19 and 76% in the massive cuff tears group. Patients were staged according to the classification with 32% in stage 1a, 11% 1b, 32% 2a and 0% 2b. CTA prevalence in patients with rotator cuff tears and massive cuff tears is higher than the one reported in American population. We consider that a revision of the Seebauer classification to be appropriate to determine its reliability.

  12. Determination of p-y Curves using Finite Element Modelling for Bucket Foundation in Undrained Soft and Medium Clay

    DEFF Research Database (Denmark)

    Hvidberg, Mogens Bonde; Ibsen, Lars Bo

    In many years the types of foundation, such as monopiles and bucket foundation which are used in the offshore wind turbine industry, have been analysed analytically with formulations that are based on much slender piles, than are used today. Because of that, the analytical calculation...... is not describing the connection between the horizontal bearing capacity of the soil and the displacement of the foundation accurate, in particular for the bucket foundation because of the much smaller slenderness of the profile. Numerical modelling is used to examine that bearing capacity the bucket foundation has...... in soft and medium clay at different dimensions of the bucket, to a horizontal displacement. After that a mathematical formulation is determined, based on (Reese et al, 1975), so it is possible to get a more accurate result in an analytical calculation....

  13. Analysis of in-situ renewal technology for the backhoe bucket bores

    Energy Technology Data Exchange (ETDEWEB)

    Torims, Toms; Ratkus, Andris; Vilcans, Janis; Zarins, Marcis; Rusa, Aldis [Department of Material Processing Technology Faculty of Transport and Mechanical Engineering Riga Technical University, Riga (Latvia)

    2011-07-01

    The overall aim of this article is to outline the progress of the research on how to develop an economically and scientifically justified backhoe buckets boreholes renewal technology by using mobile on-site technological equipment. Today the new mobile (in-situ) repair technologies are extensively used for the specialized equipment and machinery repairs. This repair technology is deployed directly on the damaged product: repair equipment is installed by using specialized centering devices. The bucket bores central axes are used as a reference base and damaged layer of material is removed mechanically applying turning operation. Subsequently the renewable surface is covered by new material layer by means of regular MIG/MAG welding. The last technological operation is final turning to the nominal diameter. Outlined renewal technology should meet high expectations – this necessitates in-depth and systematic study of pins and bores which are the most repaired objects of shovel bucket excavators. Therefore, research on established accuracy and technical requirements, both for the repaired unit and technological equipment in line with in-situ repair technology specifics, has been done. It was supported by impact analysis of the technological regimes to surface integrity with ambition to provide practical recommendations for the optimal choice of the technological regimes. Key words: in-situ repair technology, surface integrity, technological parameters.

  14. Human tears contain a chemosignal.

    Science.gov (United States)

    Gelstein, Shani; Yeshurun, Yaara; Rozenkrantz, Liron; Shushan, Sagit; Frumin, Idan; Roth, Yehudah; Sobel, Noam

    2011-01-14

    Emotional tearing is a poorly understood behavior that is considered uniquely human. In mice, tears serve as a chemosignal. We therefore hypothesized that human tears may similarly serve a chemosignaling function. We found that merely sniffing negative-emotion-related odorless tears obtained from women donors induced reductions in sexual appeal attributed by men to pictures of women's faces. Moreover, after sniffing such tears, men experienced reduced self-rated sexual arousal, reduced physiological measures of arousal, and reduced levels of testosterone. Finally, functional magnetic resonance imaging revealed that sniffing women's tears selectively reduced activity in brain substrates of sexual arousal in men.

  15. Antimicrobial compounds in tears.

    Science.gov (United States)

    McDermott, Alison M

    2013-12-01

    The tear film coats the cornea and conjunctiva and serves several important functions. It provides lubrication, prevents drying of the ocular surface epithelia, helps provide a smooth surface for refracting light, supplies oxygen and is an important component of the innate defense system of the eye providing protection against a range of potential pathogens. This review describes both classic antimicrobial compounds found in tears such as lysozyme and some more recently identified such as members of the cationic antimicrobial peptide family and surfactant protein-D as well as potential new candidate molecules that may contribute to antimicrobial protection. As is readily evident from the literature review herein, tears, like all mucosal fluids, contain a plethora of molecules with known antimicrobial effects. That all of these are active in vivo is debatable as many are present in low concentrations, may be influenced by other tear components such as the ionic environment, and antimicrobial action may be only one of several activities ascribed to the molecule. However, there are many studies showing synergistic/additive interactions between several of the tear antimicrobials and it is highly likely that cooperativity between molecules is the primary way tears are able to afford significant antimicrobial protection to the ocular surface in vivo. In addition to effects on pathogen growth and survival some tear components prevent epithelial cell invasion and promote the epithelial expression of innate defense molecules. Given the protective role of tears a number of scenarios can be envisaged that may affect the amount and/or activity of tear antimicrobials and hence compromise tear immunity. Two such situations, dry eye disease and contact lens wear, are discussed here. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Tear progression of symptomatic full-thickness and partial-thickness rotator cuff tears as measured by repeated MRI.

    Science.gov (United States)

    Kim, Yang-Soo; Kim, Sung-Eun; Bae, Sung-Ho; Lee, Hyo-Jin; Jee, Won-Hee; Park, Chang Kyun

    2017-07-01

    The purpose of this study was to analyse the natural course of symptomatic full-thickness and partial-thickness rotator cuff tears treated non-operatively and to identify risk factors affecting tear enlargement. One hundred and twenty-two patients who received non-surgical treatment for a partial- or full-thickness supraspinatus tear were included in this study. All rotator cuff tears were diagnosed with magnetic resonance imaging (MRI), and the same modality was used for follow-up studies. Follow-up MRI was performed after at least a 6-month interval. We evaluated the correlation between tear enlargement and follow-up duration. Eleven risk factors were analysed by both univariate and multivariate analyses to identify factors that affect enlargement of rotator cuff tears. The mean follow-up period was 24.4 ± 19.5 months. Out of 122 patients, 34 (27.9%) patients had an initial full-thickness tear and 88 (72.1%) patients had a partial-thickness tear. Considering all patients together, tear size increased in 51/122 (41.8%) patients, was unchanged in 65/122 (53.3%) patients, and decreased in 6/122 (4.9%) patients. Tear size increased for 28/34 (82.4%) patients with full-thickness tears and 23/88 (26.1%) patients with partial-thickness tears. From the two groups which were followed over 12 months, a higher rate of enlargement was observed in full-thickness tears than in partial-thickness tears (6-12 months, n.s.; 12-24 months, P = 0.002; over 24 months, P rotator cuff tears and 23/88 (26.1%) of symptomatic partial-thickness tears increased in size over a follow-up period of 6-100 months. Full-thickness tears showed a higher rate of enlargement than partial-thickness tears regardless of the follow-up duration. Univariate and multivariate analyses suggested that full-thickness tear was the most reliable risk factor for tear enlargement. The clinical relevance of these observations is that full-thickness rotator cuff tears treated conservatively should be

  17. Examination of rotator cuff re-tear

    International Nuclear Information System (INIS)

    Kitahara, Hiroyuki; Yabe, Yoshihiro; Norimatsu, Takahiro; Adachi, Shinji; Sera, Keisuke

    2010-01-01

    The six-month post-operative re-tear rate in 72 arthroscopic rotator cuff repair cases was 16.3% by MRI. The re-tear rate of massive tears was 50%. We investigated the details of the re-tears by MRI and arthroscopic findings. High re-tear rates were connected with cuff tear size and fatty degeneration of muscle belly. Cases with poor cuff quality in arthroscopically showed high re-tear rate. These results suggest that surgery operation should be performed as soon as possible after diagnosis of cuff tear to obtain good results. Cases with damage of long head of the biceps (LHB) are likely to develop impingement causes of re-tears. Some type of rehabilitation is required to avoid impingement in such cases. (author)

  18. ANALYSIS OF INFLUENCE OF DESIGN CHARACTERISTICS OF INCLINED BUCKET ELEVATOR ON THE POWER OF ITS DRIVE

    Directory of Open Access Journals (Sweden)

    V. M. Bohomaz

    2016-12-01

    Full Text Available Purpose.One of the main elements of the inclined belt bucket elevators is their drive. To determine the drive power, it is necessary to carry out calculations according to standard methods, which are described in the modern literature. The basic design parameters are the productivity, lifting height, type and properties of the transported material, the angle of inclination. It is necessary to build a parametric dependence of the driving power of the elevator on its design parameters, which takes into account the standard sizes and types of buckets and belts. Methodology. Using the methodology of traction calculation of inclined belt bucket elevator there were built parametric dependences of efforts in specific points of the route of the elevator, as well as the parametric dependences of the drive power of high-speed elevators with deep and shallow buckets on their design parameters and characteristics. Findings. On the basis of constructed parametric dependencies, it was found that the function of changing the value of the elevator’s power from design capacity (at fixed lifting height, type of cargo, belt speed is piecewise constant and monotonically increasing. It was built a graphical representation of elevator drive power on the angle of its inclination within acceptable limits of change. The resulting relationship is non-linear and monotonically decreasing. In general terms the intervals of project performance values, which provide a constant value of drive power of inclined elevator were defined. As an example of the obtained results it was observed the process of dependence construction of the drive power on design capacity and inclination angle of the elevator for transporting the fine coal. Originality. For the first time there were constructed the parametric dependences of drive power of inclined bucket elevator on its design parameters that take into account the standard sizes and types of buckets and belts. Practical value. Using

  19. What emotional tears convey : Tearful individuals are seen as warmer, but also as less competent

    NARCIS (Netherlands)

    van de Ven, Niels; Meijs, Maartje; Vingerhoets, A.J.J.M.

    Earlier research found that the mere sight of tears promotes the willingness to provide support to the person shedding the tears. Other research, however, found that deliberate responses towards tearful persons could be more negative as well. We think this is because tears have ambivalent effects on

  20. A Bibliometric Assessment of Global Ice Bucket Challenge (Amyotrophic Lateral Sclerosis) Research.

    Science.gov (United States)

    Ram, Shri

    2016-10-01

    This study is a quantitative and qualitative assessment of the global research trends on amyotrophic lateral sclerosis (ALS) (popularly known as Ice Bucket Challenge), through related literatures retrieved from SCOPUS multidisciplinary database for the period 1974-2013. This study is aimed at analyzing the literature on ALS in terms of document type, language, annual growth, productive country, journal, authors, subject, and most cited articles. The bibliographic data for this study was retrieved from the SCOPUS database using keywords 'amyotrophic lateral sclerosis', 'motor neurone disease', 'Charcot disease', 'Lou Gehrig's disease', 'Ice Bucket Challenge' available in title, abstract, and keyword fields of Scopus database from 1974 to 2013. The literature analysis included 21,750 articles during the period from 1974 to 2013 in different areas of ALS. USA was the most productive country in terms of literature produced, while Neurology was the most productive journal. An intensive awareness created by 'Ice Bucket Challenge' has attracted masses, and an intensive growth of literature is pertinent on ALS. The results of this study are expressed in terms of growth of literature, output of individual countries, and authors, and will be helpful in collaborative research in future.

  1. Cell-Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath

    Science.gov (United States)

    2016-07-01

    Engineering . Overlap: None Title: “Development of Novel Bioartificial Ligament Using Autologous Biological Scaffold and Cells” Grant#: W81XWH-13-2-0030...patient to rapid joint degeneration (i.e., osteoarthritis). Tissue engineering approaches, including the combination of cells, scaffolds, and...electrospun nano/microfibers comprising engineered scaffolds can mimic the ultrastructure of the native meniscal extracellular matrix (ECM); when seeded with

  2. Gas turbine bucket with impingement cooled platform

    Science.gov (United States)

    Jones, Raphael Durand

    2002-01-01

    In a turbine bucket having an airfoil portion and a root portion, with a substantially planar platform at an interface between the airfoil portion and root portion, a platform cooling arrangement including at least one bore in the root portion and at least one impingement cooling tube seated in the bore, the tube extending beyond the bore with an outlet in close proximity to a targeted area on an underside of the platform.

  3. A Controlled Study on the Correlation between Tear Film Volume and Tear Film Stability in Diabetic Patients.

    Science.gov (United States)

    Eissa, Iman M; Khalil, Noha M; El-Gendy, Heba A

    2016-01-01

    Purpose. To assess the tear film quantity and correlate it with the quality and stability of the tear film in diabetics and compare them to age matched controls. Introduction. Diabetes affects tear film parameters in multiple ways. Poor metabolic control and neuropathy are postulated factors. To further understand how diabetes affects tear film parameters this study was conducted. Subjects and Methods. Tear meniscus height was measured by anterior segment OCT, along with tear thinning time, a subtype of noninvasive tear break-up time, and blinking rate per minute which were all recorded for 22 diabetic patients. Correlations between these tear film parameters were studied and then compared to 16 age matched controls. Results. A statistically significant difference was found in blinking rate between the diabetic and the control group (P = 0.002), with higher blinking rate among diabetics. All tear film parameters were negatively correlated with duration of diabetes. A positive correlation was found between tear film volume and stability. Conclusion. Diabetes affects the tear film in various ways. Diabetics should be examined for dry eye signs even in absence of symptoms which may be masked by associated neuropathy. Duration of diabetes has an impact on tear film status.

  4. TFOS DEWS II Tear Film Report.

    Science.gov (United States)

    Willcox, Mark D P; Argüeso, Pablo; Georgiev, Georgi A; Holopainen, Juha M; Laurie, Gordon W; Millar, Tom J; Papas, Eric B; Rolland, Jannick P; Schmidt, Tannin A; Stahl, Ulrike; Suarez, Tatiana; Subbaraman, Lakshman N; Uçakhan, Omür Ö; Jones, Lyndon

    2017-07-01

    The members of the Tear Film Subcommittee reviewed the role of the tear film in dry eye disease (DED). The Subcommittee reviewed biophysical and biochemical aspects of tears and how these change in DED. Clinically, DED is characterized by loss of tear volume, more rapid breakup of the tear film and increased evaporation of tears from the ocular surface. The tear film is composed of many substances including lipids, proteins, mucins and electrolytes. All of these contribute to the integrity of the tear film but exactly how they interact is still an area of active research. Tear film osmolarity increases in DED. Changes to other components such as proteins and mucins can be used as biomarkers for DED. The Subcommittee recommended areas for future research to advance our understanding of the tear film and how this changes with DED. The final report was written after review by all Subcommittee members and the entire TFOS DEWS II membership. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Assessment of lamellar tearing

    International Nuclear Information System (INIS)

    McEnerney, J.W.

    1978-03-01

    Information on lamellar tearing is summarized and related to proposed ASME Code requirements. Lamellar tearing is characterized as a complex phenomenon related to poor short transverse ductility and through-thickness strain. The material, welding, and design variables that affect lamellar tearing are shown to be complex and interrelated. The commonly reported tests for assessing material susceptibility are described, with the controversy over their validity being carefully detailed. Although the use of a nondestructive test such as ultrasonic examination is most desirable, a widely applicable test method does not appear to be available. Of the destructive tests, the short transverse tensile reduction-of-area currently offers the most applicable means of assessing material susceptibility. However, because of the importance of matrix toughness, the short transverse Charpy V-notch test should be considered for use as an additional test if acceptance limits are developed. The ultrasonic detection of lamellar tears is susceptible to interpretation errors, which can make it overly conservative and lead to unnecessary repairs. The repair of tears is described as costly, difficult, and sometimes ineffective. Current design requirements appear to preclude any failures during static and fatigue service loads. However, without improvement of short transverse ductility, certain dynamic service loads could cause lamellar tearing failures. Two alternate design paths are recommended to prevent tearing during fabrication or service loading. The current and proposed ASME requirements dealing with lamellar tearing are reviewed and recommendations are made

  6. Off-bucket Proton Losses during Ramping

    CERN Document Server

    Catalan-Lasheras, N

    1998-01-01

    In this paper, we report a study undertaken to determine whether longitudinal and transverse amplitudes become coupled before the loss of the off-bucket protons during the ramp. We compute the synchro tron as well as the betatron tune changes with momentum and determine if synchro-betatron resonances blow-up the transverse particle amplitude. A strong coupling might allow a betatron cleaning of the se particles before they are outside the momentum acceptance of the machine. We show that this is not the case, justifying the need of momentum cleaning.

  7. Crafting the Set of Buckets in a R&D Portfolio

    DEFF Research Database (Denmark)

    Santiago, Leonardo; Soares, Verônica Mariana Oliveira

    2017-01-01

    of buckets. Our framework is composed of four strategic constructs, namely technology, marketing, capabilities and organizational processes. In addition, the external environment is also taken into account. We offer a series of propositions grounded on some theoretical insights concerning the strategic...

  8. Bone signal abnormality, as seen on knee joint MRI : relationship between its location and associated injury

    International Nuclear Information System (INIS)

    Kim, Young Nam; Kim, Baek Hyun; Jung, Hoe Seok; Na, Eui Sung; Seol, Hye Young; Cha, In Ho; Lim, Hong Chul

    1998-01-01

    The purpose of the study was to evaluate the relationship between the location of bone signal abnormality and associated injury, as seen on MR, in patients with acute knee joint injury. Materials and Methods: Thirty-six patients with acute knee injury and bone signal abnormalities on MR were included in this study. The femur and tibia were each divided into six compartments, namely the anteromedial, medial, posteromedial,anterolateral, lateral, and posterolateral ; these were obtained in each knee joint. We evaluated the location of bone signal abnormality and the corresponding arthroscopic or operative findings of injury to ligaments and menisci. Cases with signal abnormalities involving more than three compartments were excluded. Results : Bone signal abnormalities were demonstrated in 51 compartments. Most(84%, 43/51) were noted in the lateral half of the knee joint, the most common location being the tibio- posterolateral compartment(13/51). The femoro-lateral(11/51) and tibio- anterolateral compartment(8/51) were the next most common locations. All cases(13/13)with bone signal abnormality in the tibio- posterolateral compartment had tears at the anterior cruciate ligament,while 9 of 11 cases(81%) with abnormality in the femoro- lateral compartment had tears at the anterior cruciate ligament. Six of eight cases(75%) with signal abnormality in the tibio- anterolateral compartment had tears at the posterior cruciate ligament ; 31 of 43 cases (72%) with abnormality in the lateral half of the knee joint had tears at the medial collateral ligament. Six of eight cases(75%) with signal abnormality in the medial half of the knee joint had tears at the medial meniscus, but no lateral meniscal tear was found. Among patients with signal abnormality in the lateral half of the knee joint, the tear was lateral meniscal in nine of 43 cases(21%) and medial meniscal in six of 43(14%). Conclusion : The location of bone signal abnormality, as seen on knee MR, inpatients with

  9. Tear dynamics in healthy and dry eyes.

    Science.gov (United States)

    Cerretani, Colin F; Radke, C J

    2014-06-01

    Dry-eye disease, an increasingly prevalent ocular-surface disorder, significantly alters tear physiology. Understanding the basic physics of tear dynamics in healthy and dry eyes benefits both diagnosis and treatment of dry eye. We present a physiological-based model to describe tear dynamics during blinking. Tears are compartmentalized over the ocular surface; the blink cycle is divided into three repeating phases. Conservation laws quantify the tear volume and tear osmolarity of each compartment during each blink phase. Lacrimal-supply and tear-evaporation rates are varied to reveal the dependence of tear dynamics on dry-eye conditions, specifically tear osmolarity, tear volume, tear-turnover rate (TTR), and osmotic water flow. Predicted periodic-steady tear-meniscus osmolarity is 309 and 321 mOsM in normal and dry eyes, respectively. Tear osmolarity, volume, and TTR all match available clinical measurements. Osmotic water flow through the cornea and conjunctiva contribute 10 and 50% to the total tear supply in healthy and dry-eye conditions, respectively. TTR in aqueous-deficient dry eye (ADDE) is only half that in evaporative dry eye (EDE). The compartmental periodic-steady tear-dynamics model accurately predicts tear behavior in normal and dry eyes. Inclusion of osmotic water flow is crucial to match measured tear osmolarity. Tear-dynamics predictions corroborate the use of TTR as a clinical discriminator between ADDE and EDE. The proposed model is readily extended to predict the dynamics of aqueous solutes such as drugs or fluorescent tags.

  10. Quantitative analysis of tear film fluorescence and discomfort during tear film instability and thinning.

    Science.gov (United States)

    Begley, Carolyn; Simpson, Trefford; Liu, Haixia; Salvo, Eliza; Wu, Ziwei; Bradley, Arthur; Situ, Ping

    2013-04-12

    The purpose of this study was to test the association between tear film fluorescence changes during tear break-up (TBU) or thinning and the concurrent ocular sensory response. Sixteen subjects kept one eye open as long as possible (MBI), indicated their discomfort level continuously, and rated ocular sensations of irritation, stinging, burning, pricking, and cooling using visual analog scales (VAS). Fluorescence of the tear film was quantified by a pixel-based analysis of the median pixel intensity (PI), TBU, and percentage of dark pixels (DarkPix) over time. A cutoff of 5% TBU was used to divide subjects into either break-up (BU) or minimal break-up (BUmin) groups. Tear film fluorescence decreased (median PI) and the percentage of TBU and DarkPix increased in all trials, with the rate significantly greater in the BU than the BUmin group (Mann-Whitney U test, P film thinning best explains decreasing tear film fluorescence during trials. This was highly correlated with increasing ocular discomfort, suggesting that both tear film thinning and TBU stimulate underlying corneal nerves, although TBU produced more rapid stimulation. Slow increases in tear film hyperosmolarity may cause the gradual increase in discomfort during slow tear film thinning, whereas the sharp increases in discomfort during TBU suggest a more complex stimulus.

  11. Knee extensor muscle strength in middle-aged and older individuals undergoing arthroscopic partial meniscectomy

    DEFF Research Database (Denmark)

    Hall, Michelle; Juhl, Carsten B; Lund, Hans

    2015-01-01

    OBJECTIVE: People with meniscal tears are at high risk to develop or progress knee osteoarthritis. Knee extensor weakness is considered a risk factor for osteoarthritis and is often reported in these individuals. The purpose of this systematic review and meta-analysis was to investigate knee...... for a meniscal tear and used either a healthy control group or the contralateral leg to compare knee extensor muscle strength were included. Methodological quality was assessed using guidelines from the Centre for Reviews and Dissemination. RESULTS: Eleven studies, including predominately males were included (n...... and knee extensor muscle weakness are risk factors for osteoarthritis these results highlight the clinical importance of addressing muscle weakness in these individuals. This article is protected by copyright. All rights reserved....

  12. A Controlled Study on the Correlation between Tear Film Volume and Tear Film Stability in Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Iman M. Eissa

    2016-01-01

    Full Text Available Purpose. To assess the tear film quantity and correlate it with the quality and stability of the tear film in diabetics and compare them to age matched controls. Introduction. Diabetes affects tear film parameters in multiple ways. Poor metabolic control and neuropathy are postulated factors. To further understand how diabetes affects tear film parameters this study was conducted. Subjects and Methods. Tear meniscus height was measured by anterior segment OCT, along with tear thinning time, a subtype of noninvasive tear break-up time, and blinking rate per minute which were all recorded for 22 diabetic patients. Correlations between these tear film parameters were studied and then compared to 16 age matched controls. Results. A statistically significant difference was found in blinking rate between the diabetic and the control group (P=0.002, with higher blinking rate among diabetics. All tear film parameters were negatively correlated with duration of diabetes. A positive correlation was found between tear film volume and stability. Conclusion. Diabetes affects the tear film in various ways. Diabetics should be examined for dry eye signs even in absence of symptoms which may be masked by associated neuropathy. Duration of diabetes has an impact on tear film status.

  13. Software Simulation of Hot Tearing

    DEFF Research Database (Denmark)

    Andersen, S.; Hansen, P.N.; Hattel, Jesper Henri

    1999-01-01

    The brittleness of a solidifying alloy in a temperature range near the solidus temperature has been recognised since the fifties as the mechanism responsible for hot tearing. Due to this brittlenes, the metal will crack under even small amounts of strain in that temperature range. We see these hot...... tears in castings close to hot centres, where the level of strain is often too high.Although the hot tearing mechanism is well understood, until now it has been difficult to do much to reduce the hot tearing tendency in a casting. In the seventies, good hot tearing criteria were developed by considering...... the solidification rate and the strain rate of the hot tear prone areas. But, until recently it was only possible to simulate the solidification rate, so that the criteria could not be used effectively.Today, with new software developments, it is possible to also simulate the strain rate in the hot tear prone areas...

  14. Effects of topical cyclosporine a plus artificial tears versus artificial tears treatment on conjunctival goblet cell density in dysfunctional tear syndrome.

    Science.gov (United States)

    Demiryay, Elvan; Yaylali, Volkan; Cetin, Ebru Nevin; Yildirim, Cem

    2011-09-01

    The aim was to compare the effects of topical cyclosporine A and artificial tears combination with artificial tears alone in patients with dysfunctional tear syndrome (DTS). Forty-two eyes of 42 patients with DTS were enrolled in the study. The inclusion criteria for the study were Schirmer I (without anesthesia) scores below 10 mm/5 min and tear film break-up time (BUT) below 10 sec. The patients were randomly divided into two groups. The study group (22 patients) underwent 0.05% cyclosporine A treatment twice a day and preservative-free artificial tears for four times a day for 4 months. The control group (20 patients) was administered only preservative-free artificial tears four times a day for 4 months. The BUT, Schirmer test scores, corneal fluorescein staining, conjunctival lissamine green staining, and goblet cell density derived by impression cytology were recorded before and after treatment in each group. In the study group, all parameters improved statistically significantly after treatment at the 4-month follow-up compared with the pretreatment values (Ptears treatment significantly increases goblet cell density, decreases the signs of DTS, and improves ocular surface health.

  15. Evaluation of changes in vertical ground reaction forces as indicators of meniscal damage after transection of the cranial cruciate ligament in dogs.

    Science.gov (United States)

    Trumble, Troy N; Billinghurst, R Clark; Bendele, Alison M; McIlwraith, C Wayne

    2005-01-01

    To determine whether decreases in peak vertical force of the hind limb after transection of the cranial cruciate ligament (CrCL) would be indicative of medial meniscal damage in dogs. 39 purpose-bred adult male Walker Hounds. The right CrCL was transected arthroscopically. Force plate measurements of the right hind limb were made prior to and 2, 4, 10, and 18 weeks after transection of the CrCL. Only dogs with > or =10% decreases in peak vertical force after week 2 were considered to have potential meniscal damage. Dogs that did not have > or =10% decreases in peak vertical force at any time point after week 2 were assigned to group 1. Group 2 dogs had > or =10% decreases in peak vertical force from weeks 2 to 4 only. Group 3 and 4 dogs had > or =10% decreases in peak vertical force from weeks 4 to 10 only or from weeks 10 to 18 only, respectively. Damage to menisci and articular cartilage was graded at week 18, and grades for groups 2 to 4 were compared with those of group 1. The percentage change in peak vertical force and impulse area was significantly different in groups 2 (n = 4), 3 (4), and 4 (4) at the end of each measurement period (weeks 4, 10, and 18, respectively) than in group 1 (27). The meniscal grade for groups 2 to 4 was significantly higher than for group 1. A > or =10% decrease in peak vertical force had sensitivity of 52% and accuracy of 72% for identifying dogs with moderate to severe medial meniscal damage. In dogs with transected or ruptured CrCLs, force plate analysis can detect acute exacerbation of lameness, which may be the result of secondary meniscal damage, and provide an objective noninvasive technique that delineates the temporal pattern of medial meniscal injury.

  16. Meniscal replacement using a porous polymer prosthesis : A preliminary study in the dog

    NARCIS (Netherlands)

    Veth, RPH; Jansen, HWB; Nielsen, HKL; deGroot, JH; Pennings, AJ

    A porous polyurethane prosthesis was used to replace the lateral meniscus in the dog. After an initial ingrowth of fibrous tissue, the prostheses became filled with tissue strongly resembling normal meniscal fibrocartilage. Although less severe than seen after total meniscectomy, cartilage

  17. Classification of ulnar triangular fibrocartilage complex tears. A treatment algorithm for Palmer type IB tears.

    Science.gov (United States)

    Atzei, A; Luchetti, R; Garagnani, L

    2017-05-01

    The classical definition of 'Palmer Type IB' triangular fibrocartilage complex tear, includes a spectrum of clinical conditions. This review highlights the clinical and arthroscopic criteria that enable us to categorize five classes on a treatment-oriented classification system of triangular fibrocartilage complex peripheral tears. Class 1 lesions represent isolated tears of the distal triangular fibrocartilage complex without distal radio-ulnar joint instability and are amenable to arthroscopic suture. Class 2 tears include rupture of both the distal triangular fibrocartilage complex and proximal attachments of the triangular fibrocartilage complex to the fovea. Class 3 tears constitute isolated ruptures of the proximal attachment of the triangular fibrocartilage complex to the fovea; they are not visible at radio-carpal arthroscopy. Both Class 2 and Class 3 tears are diagnosed with a positive hook test and are typically associated with distal radio-ulnar joint instability. If required, treatment is through reattachment of the distal radio-ulnar ligament insertions to the fovea. Class 4 lesions are irreparable tears due to the size of the defect or to poor tissue quality and, if required, treatment is through distal radio-ulnar ligament reconstruction with tendon graft. Class 5 tears are associated with distal radio-ulnar joint arthritis and can only be treated with salvage procedures. This subdivision of type IB triangular fibrocartilage complex tear provides more insights in the pathomechanics and treatment strategies. II.

  18. A load-displacement based approach to assess the bearing capacity and deformations of mono-bucket foundations

    DEFF Research Database (Denmark)

    Vahdatirad, Mohammadjavad; Diaz, Alberto Troya; Nielsen, Søren

    2016-01-01

    It is now accepted that a larger effort must be made in order to optimize the design so that offshore wind turbines can be competitive with the other energy resources. In this regard, mono-buckets are known as a cost-effective offshore foundation solution. In the current study, a load–displacemen......It is now accepted that a larger effort must be made in order to optimize the design so that offshore wind turbines can be competitive with the other energy resources. In this regard, mono-buckets are known as a cost-effective offshore foundation solution. In the current study, a load...... and run the calculations is proposed. The model is validated, and its accuracy is analyzed, by comparison with field test results for a bucket foundation installed in silty, sandy soil....

  19. Numerical Study of Piping Limits for Installation of Large Diameter Buckets in Layered Sand

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Thilsted, C.L.

    2010-01-01

    The bucket foundations, often referred as ‘suction caissons’, are large cylindrical structures, typically made in steel. The bucket foundations have the potential to be the cost-effective option for offshore wind turbines, if suction assisted penetration is employed. Suction installation may cause...... gradients developing in response to applied suction and the results are presented as simple closed form solutions useful for evaluation of suction thresholds against piping. These close form solutions are compared with large scale model test, performed in a natural seabed at a test site in Frederikshavn...

  20. Development of a Chinese version of the Western Ontario Meniscal Evaluation Tool: cross-cultural adaptation and psychometric evaluation.

    Science.gov (United States)

    Tong, W W; Wang, W; Xu, W D

    2016-08-15

    The Western Ontario Meniscal Evaluation Tool (WOMET) is a questionnaire designed to evaluate the health-related quality of life (HRQOL) of patients with meniscal pathology. Our study aims to culturally adapt and validate the WOMET into a Chinese version. We translated the WOMET into Chinese. Then, a total of 121 patients with meniscal pathology were invited to participate in this study. To assess the test-retest reliability, the Chinese version WOMET was completed twice at 7-day intervals by the participants. The construct validity was assessed using Pearson's correlation coefficient or Spearman's correlation to test for correlations among the Chinese version WOMET and the eight domains of Short Form-36 (SF-36), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the International Knee Documentation Committee (IKDC) score. Responsiveness was tested by comparison of the preoperative and postoperative scores of the Chinese version WOMET. The test-retest reliability of the overall scale and different domains were all found to be excellent. The Cronbach's α was 0.90. The Chinese version WOMET correlated well with other questionnaires which suggested good construct validity. We observed no ceiling and floor effects of the Chinese version WOMET. We also found good responsiveness for the effect size, and the standardized response mean values were 0.86 and 1.11. The Chinese version of the WOMET appears to be reliable and valid in evaluating patients with meniscal pathology.

  1. Meniscal tissue regeneration in porous 50/50 copoly(L-lactide/epsilon-caprolactone) implants

    NARCIS (Netherlands)

    de Groot, J. H.; Zijlstra, F. M.; Kuipers, HW; Pennings, A. J.; Veth, RPH; Jansen, HWB

    Porous materials of a high-molecular-weight 50/50 copolymer of L-lactide and epsilon-caprolactone with different compression moduli were used for meniscal repair. In contrast to the previously used 4,4'-diphenylmethane and 1,6-trans-cyclohexane diisocyanates containing polyurethanes, degradation

  2. Bucket drill

    Energy Technology Data Exchange (ETDEWEB)

    Bezverkhiy, V.M.; Nabokov, I.M.; Podoksik, D.Z.; Sadovskiy, S.S.; Shanyukevich, V.A.

    1983-01-01

    The bucket drill including a cylindrical housing with bottom, ground intake windows and cutting knives is hinged to the housing, the mechanism of rotation of the cutting knives including rods connected by the cutter knives, and drive shaft is distinguished by the fact that in order to improve the effectiveness of drilling by automatic change in the angle of cutting depending on the strength of the drillable rock, the drill is equipped with elastic elements and cap with annular slits in which there are elastic elements. The mechanism of rotation of the cutting knives is equipped with levers hinged to the housing, pins with shaft and rocker arm. The rods are made with a slit and from one end are rigidly connected to the cutting knives, and from the other end to the levers by means of pins which are arranged in slits of the rod with the possibility of movement. The upper ends of the levers are installed with the possibility of movement in the pins whose shafts are arranged with the possibility of rotation in the rocker arm rigidly connected to the drive shaft. The drive shaft is equipped with cantilevers installed in the cap with the possibility of rotation and interaction with the elastic elements.

  3. Treatment of Painful, Irreparable Partial Meniscal Defects With a Polyurethane Scaffold: Midterm Clinical Outcomes and Survival Analysis.

    Science.gov (United States)

    Dhollander, Aad; Verdonk, Peter; Verdonk, René

    2016-10-01

    A biodegradable polyurethane scaffold was designed to fulfill a challenging clinical need in the treatment of patients with painful, irreparable partial meniscal defects. The use of an acellular polyurethane scaffold for new tissue generation in irreparable, partial meniscal defects provides both midterm pain relief and improved functionality. Case series; Level of evidence, 4. A total of 44 patients with irreparable, partial meniscal defects (29 medial and 15 lateral) were implanted with a polyurethane scaffold in a prospective, single-arm proof-of-principle study with a minimum 5-year follow-up. Clinical outcomes were measured with the visual analog scale (VAS) for pain, International Knee Documentation Committee (IKDC), and Knee injury and Osteoarthritis Outcome Score (KOOS) at baseline and at 2- and 5-year follow-up. Magnetic resonance imaging (MRI) was used to evaluate the meniscal implant and cartilage status of the index compartment. Kaplan-Meier time-to-treatment failure distributions were also performed. Removal of the scaffold, conversion to a meniscal transplant, or unicompartmental/total knee arthroplasty was used as endpoints. Seven patients were lost to follow-up (15.9%). The patients who participated in this study showed significant clinical improvement after surgery (mean [±SD] at baseline, 2 years, and 5 years: 56.2 ± 21.6, 24.6 ± 22.7, and 19.3 ± 26.9, respectively [VAS]; 206.5 ± 79.7, 329.8 ± 108.9, and 333.6 ± 112.2, respectively [total KOOS]). MRI of the scaffolds showed a smaller sized implant when compared with the native meniscus with an irregular surface at 2- and 5-year follow-up. A stable cartilage status of the index compartment at 5-year follow-up was demonstrated in 46.7% of patients compared with the baseline status. During the follow-up period, 62.2% of the implants survived. At final follow-up, 66.7% of the medial scaffolds were still functioning versus 53.8% of the lateral scaffolds. A polyurethane meniscal implant can

  4. A Preliminary Study on Bucket Foundations under Transient Lateral Loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo; Nielsen, Søren Kjær

    2013-01-01

    This study aims at investigating the behaviour of monopod bucket foundations through a physical model. The foundation is installed in dense water-saturated sand and is subjected to lateral load applied at different rates. The different loading rates allow for exploring the patterns of response of...

  5. Artificial tears potpourri: a literature review

    Directory of Open Access Journals (Sweden)

    Moshirfar M

    2014-07-01

    Full Text Available Majid Moshirfar,1 Kasey Pierson,2,* Kamalani Hanamaikai,3,* Luis Santiago-Caban,1 Valliammai Muthappan,1 Samuel F Passi11Department of Ophthalmology, John A Moran Eye Center, University of Utah, Salt Lake City, UT, USA; 2University of Arizona College of Medicine, Phoenix, Phoenix, AZ, USA; 3A T Still University, School of Osteopathic Medicine in Arizona, Mesa, AZ, USA *These authors contributed equally to this work Abstract: Numerous brands and types of artificial tears are available on the market for the treatment of dysfunctional tear syndrome. Past literature has focused on comparing the components of these products on patient’s clinical improvement. The wide array of products on the market presents challenges to both clinicians and patients when trying to choose between available tear replacement therapies. Different formulations affect patients based on etiology and severity of disease. In order to provide an unbiased comparison between available tear replacement therapies, we conducted a literature review of existing studies and National Institutes of Health clinical trials on commercially available, brand name artificial tears. Outcomes evaluated in each study, as well as the percent of patients showing clinical and symptomatic improvement, were analyzed. Fifty-one studies evaluating different brands of artificial tears, and their efficacy were identified. Out of the 51 studies, 18 were comparison studies testing brand name artificial tears directly against each other. Nearly all formulations of artificial tears provided significant benefit to patients with dysfunctional tear syndrome, but some proved superior to others. From the study data, a recommended treatment flowchart was derived. Keywords: dry eye, tear film, dysfunctional tear syndrome, ophthalmic lubricant, artificial tears, lipid layer, tear osmolarity, TBUT, Systane®, Refresh®, Blink®, GenTeal®, Soothe®, Lacrisert®, ocular surface inflammatory disease, Sjogren

  6. Idiopathic Bilateral Bloody Tearing

    Directory of Open Access Journals (Sweden)

    Emrullah Beyazyıldız

    2015-01-01

    Full Text Available Bloody tear is a rare and distinct clinic phenomenon. We report a case presenting with the complaint of recurrent episodes of bilateral bloody tearing. A 16-year-old girl presented to our clinic with complaint of bloody tearing in both eyes for 3 months. Bloody tearing was not associated with her menses. A blood-stained discharge from the punctum was not observed during the compression of both nasolacrimal ducts. Nasolacrimal passage was not obstructed. Imaging studies such as dacryocystography and gradient-echo magnetic resonance imaging (MRI of nasolacrimal canal were normal. Intranasal endoscopic evaluation was normal. We collected samples from bloody tears two times and pathological examination was performed. Pathological analysis showed lots of squamous cells and no endometrial cells; dysplastic cells were found. Further evaluations for underlying causes were unremarkable. No abnormalities were found in ophthalmologic, radiologic, and pathologic investigations. This condition is likely a rare abnormality and the least recognized aetiology for the idiopathic phenomenon.

  7. Percentage Level of Tannin fur Rabbit for Leather Concerning Stitch Tearing Strength, Tearing Strength and Flexibility

    Directory of Open Access Journals (Sweden)

    Mustakim Mustakim

    2012-02-01

    Full Text Available The purpose of this study was to find out the appropriate of tannin level for rabbit fur leather concerning stitch tearing strength, tearing strength, and flexibility. The result were expected to contribute good information for the society, leather craftsman, and further researchers about fur leather tanning especially rabbit fur leather with tannin concerning stitch tearing strength, tearing strength and flexibility. The material that used were 12 pieces of four months of rabbit skin. The research method was Completely Randomized Design, consist of three treatments of tannin, they were: M1 (mimosa 15%, M2 (mimosa 20%, and M3 (mimosa 25%. Each of treatment hold on four repetition, the variables which measured were stitch tearing strength, tearing strength, and flexibility of fur leather. Data were  analysed by analysis variance followed by Duncan’s Multiple Range Test. The result of this research indicate that the use level of tannin give significant influence (P<0.05 among stitch tearing strength, tearing strength. It gave a very significant influence (P<0.01 for flexibility of rabbit fur leather. Based on the result, can be concluded that 25 % of tannin (mimosa, produce the best  result on stitch tearing strength and tearing strength. The increase of tannin offer will decrease the flexibility of fur leather but the lowest tannin produced the best flexibility of fur leather (15 percent. The best quality of rabbit fur leather produced by 25 % of tannin.   Keywords : leather, tannin, quality

  8. Climate Prediction Center (CPC) Global Monthly Leaky Bucket Soil Moisture Analysis

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly global soil moisture, runoff, and evaporation data sets produced by the Leaky Bucket model at 0.5? ? 0.5? resolution for the period from 1948 to the present....

  9. Associations of anatomical measures from MRI with radiographically defined knee osteoarthritis score, pain, and physical functioning.

    Science.gov (United States)

    Sowers, Maryfran; Karvonen-Gutierrez, Carrie A; Jacobson, Jon A; Jiang, Yebin; Yosef, Matheos

    2011-02-02

    The prevalence of knee osteoarthritis is traditionally based on radiographic findings, but magnetic resonance imaging is now being used to provide better visualization of bone, cartilage, and soft tissues as well as the patellar compartment. The goal of this study was to estimate the prevalences of knee features defined on magnetic resonance imaging in a population and to relate these abnormalities to knee osteoarthritis severity scores based on radiographic findings, physical functioning, and reported knee pain in middle-aged women. Magnetic resonance images of the knee were evaluated for the location and severity of cartilage defects, bone marrow lesions, osteophytes, subchondral cysts, meniscal and/or ligamentous tears, effusion, and synovitis among 363 middle-aged women (724 knees) from the Michigan Study of Women's Health Across the Nation. These findings were related to Kellgren-Lawrence osteoarthritis severity scores from radiographs, self-reported knee pain, self-reported knee injury, perception of physical functioning, and physical performance measures to assess mobility. Radiographs, physical performance assessment, and interviews were undertaken at the 1996 study baseline and again (with the addition of magnetic resonance imaging assessment) at the follow-up visit during 2007 to 2008. The prevalence of moderate-to-severe knee osteoarthritis changed from 3.7% at the baseline assessment to 26.7% at the follow-up visit eleven years later. Full-thickness cartilage defects of the medial, lateral, and patellofemoral compartments were present in 14.5% (105 knees), 4.6% (thirty-three knees), and 26.2% (190 knees), respectively. Synovitis was identified in 24.7% (179) of the knees, and joint effusions were observed in 70% (507 knees); 21.7% (157) of the knees had complex or macerated meniscal tears. Large osteophytes, marked synovitis, macerated meniscal tears, and full-thickness tibial cartilage defects were associated with increased odds of knee pain and with

  10. Artificial tears potpourri: a literature review

    Science.gov (United States)

    Moshirfar, Majid; Pierson, Kasey; Hanamaikai, Kamalani; Santiago-Caban, Luis; Muthappan, Valliammai; Passi, Samuel F

    2014-01-01

    Numerous brands and types of artificial tears are available on the market for the treatment of dysfunctional tear syndrome. Past literature has focused on comparing the components of these products on patient’s clinical improvement. The wide array of products on the market presents challenges to both clinicians and patients when trying to choose between available tear replacement therapies. Different formulations affect patients based on etiology and severity of disease. In order to provide an unbiased comparison between available tear replacement therapies, we conducted a literature review of existing studies and National Institutes of Health clinical trials on commercially available, brand name artificial tears. Outcomes evaluated in each study, as well as the percent of patients showing clinical and symptomatic improvement, were analyzed. Fifty-one studies evaluating different brands of artificial tears, and their efficacy were identified. Out of the 51 studies, 18 were comparison studies testing brand name artificial tears directly against each other. Nearly all formulations of artificial tears provided significant benefit to patients with dysfunctional tear syndrome, but some proved superior to others. From the study data, a recommended treatment flowchart was derived. PMID:25114502

  11. Ultrasound determination of rotator cuff tear repairability

    Science.gov (United States)

    Tse, Andrew K; Lam, Patrick H; Walton, Judie R; Hackett, Lisa

    2015-01-01

    Background Rotator cuff repair aims to reattach the torn tendon to the greater tuberosity footprint with suture anchors. The present study aimed to assess the diagnostic accuracy of ultrasound in predicting rotator cuff tear repairability and to assess which sonographic and pre-operative features are strongest in predicting repairability. Methods The study was a retrospective analysis of measurements made prospectively in a cohort of 373 patients who had ultrasounds of their shoulder and underwent rotator cuff repair. Measurements of rotator cuff tear size and muscle atrophy were made pre-operatively by ultrasound to enable prediction of rotator cuff repairability. Tears were classified following ultrasound as repairable or irreparable, and were correlated with intra-operative repairability. Results Ultrasound assessment of rotator cuff tear repairability has a sensitivity of 86% (p tear size (p tear size ≥4 cm2 or anteroposterior tear length ≥25 mm indicated an irreparable rotator cuff tear. Conclusions Ultrasound assessment is accurate in predicting rotator cuff tear repairability. Tear size or anteroposterior tear length and age were the best predictors of repairability. PMID:27582996

  12. Iatrogenic tracheal tear.

    LENUS (Irish Health Repository)

    Dias, A

    2010-10-01

    Large post intubation tracheal tears are usually detected intra-operatively due to unstable signs namely impaired ventilation and mediastinal emphysema and often require surgical management. Smaller tracheal tears are often missed during anaesthesia and recognized during the postoperative period. Conservative management should be considered in these latter cases.

  13. IMPLEMENTASI MANAJEMEN BANDWIDTH DENGAN DISIPLIN ANTRIAN HIERARCHICAL TOKEN BUCKET (HTB PADA SISTEM OPERASI LINUX

    Directory of Open Access Journals (Sweden)

    Muhammad Nugraha

    2017-01-01

    Full Text Available Important Problem on Internet networking is exhausted resource and bandwidth by some user while other user did not get service properly. To overcome that problem we need to implement traffic control and bandwidth management system in router. In this research author want to implement Hierarchical Token Bucket algorithm as queue discipline (qdisc to get bandwidth management accurately in order the user can get bandwidth properly. The result of this research is form the management bandwidth cheaply and efficiently by using Hierarchical Token Bucket qdisc on Linux operating system were able to manage the user as we want.

  14. Implementasi Manajemen Bandwidth Dengan Disiplin Antrian Hierarchical Token Bucket (HTB Pada Sistem Operasi Linux

    Directory of Open Access Journals (Sweden)

    Muhammad Nugraha

    2016-09-01

    Full Text Available Important Problem on Internet networking is exhausted resource and bandwidth by some user while other user did not get service properly. To overcome that problem we need to implement traffic control and bandwidth management system in router. In this research author want to implement Hierarchical Token Bucket algorithm as queue discipline (qdisc to get bandwidth management accurately in order the user can get bandwidth properly. The result of this research is form the management bandwidth cheaply and efficiently by using Hierarchical Token Bucket qdisc on Linux operating system were able to manage the user as we want.

  15. Numerical analysis of non-stationary free surface flow in a Pelton bucket

    Energy Technology Data Exchange (ETDEWEB)

    Hana, Morten

    1999-07-01

    Computation and analysis of flow in Pelton buckets have been carried out. First a graphical method is investigated and partially improved. In order to decide whether to improve the method further or disregard it in favour of commercial computational fluid dynamics (CFD) codes, a study on numerical methods for free surface flow was carried out. This part of this work concentrates on the theoretical background for different numerical methods, and describes some practical considerations. Although small programs were created based on the literature survey, but only one reported herein, it was soon found that commonly available numerical codes were favourable in use. A code, RIPPLE, was acquired to study the Volume of Fluid (VOF) method in detail. The commercial codes used were Flow-3D and CFX-4. These programs were used in three different cases. First, a simplified 2-dimensional case was verified experimentally. Next, a 3-dimensional fixed jet calculation was carried out. Finally, numerical calculations with relative motion between the jet and buckets were carried out with CFX-4. The conclusion is that commercial CFD codes can replace the graphical method. But careful implementation is needed in order to resolve the special features of Pelton turbines, which are the free surface, the complex geometry and the relative motion between the jet and the bucket.

  16. Anterior Segment Optical Coherence Tomography for Tear Meniscus Evaluation and its Correlation with other Tear Variables in Healthy Individuals

    Science.gov (United States)

    Dhasmana, Renu; Nagpal, Ramesh Chander

    2016-01-01

    Introduction Dry eye is one of the most common ocular diseases in this cyber era. Despite availability of multiple tests, no single test is accurate for the diagnosis of dry eye. Anterior segment optical coherence tomography is the recent tool which can be added in the armentarium of dry eye tests. Aim To evaluate tear meniscus with anterior segment optical coherence tomography and its correlation with other tear variables in normal healthy individuals. Materials and Methods In this prospective cross-sectional observational study, right eye of 203 consecutive patients were studied. All the patients were divided into three groups Group 1, 2 and 3 according to their age ≤20 years, 21-40 years and >40 years respectively. All patients underwent routine ophthalmologic examinations along with slit-lamp bio-microscopy for tear meniscus height measurement, tear film break up time, Schirmer’s I test (with anaesthesia) and optical coherence tomography imaging of inferior tear meniscus height. After focusing of the instrument with a Cross Line (CL) centered on lower tear meniscus at 6’0 clock of cornea, a 6 mm long scan was obtained. The tear meniscus height (μm) and tear meniscus area (mm2) were measured manually with help of callipers by joining upper corneo-meniscus junction to the lower lid-meniscus junction and tear meniscus height and area within the plotted line respectively and calculated by using the integrated analysis available in the custom software. Results There was significant decrease in the all tear variables with the increase in the age. According to age groups in group 1, the mean Schirmer’s (24.0±4.9)mm, tear film break up time (11.1±1.9) sec, tear meniscus height on slit lamp (600.2±167.3)mm were higher but decreased in group 2 (21.5±5.4,10.8±1.4, 597.5±186.3) and group 3 (19.8 ± 5.1, 10.2 ± 1.6, 485.6 ± 157.7) respectively. Schirmer’s test values and tear film break up time were similar in both sexes (p=0.1 and p= 0.9). Tear meniscus

  17. Meniscal T1rho and T2 measured with 3.0T MRI increases directly after running a marathon

    Energy Technology Data Exchange (ETDEWEB)

    Stehling, Christoph [University of California, Musculoskeletal and Quantitative Imaging Group (MQIR), Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); University of Muenster, Department of Clinical Radiology, Muenster (Germany); Luke, Anthony [University of California, Department of Orthopedic Surgery, San Francisco, CA (United States); Stahl, Robert [University of California, Musculoskeletal and Quantitative Imaging Group (MQIR), Department of Radiology and Biomedical Imaging, San Francisco, CA (United States); Ludwig Maximilians University of Munich, Department of Clinical Radiology, Munich (Germany); Baum, Thomas; Joseph, Gabby; Pan, Judong; Link, Thomas M. [University of California, Musculoskeletal and Quantitative Imaging Group (MQIR), Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

    2011-06-15

    To prospectively evaluate changes in T1rho and T2 relaxation time in the meniscus using 3.0 T MRI in asymptomatic knees of marathon runners and to compare these findings with those of age-matched healthy subjects. Thirteen marathon runners underwent 3.0 T MRI including T1rho and T2 mapping sequences before, 48-72 h after, and 3 months after competition. Ten controls were examined at baseline and after 3 months. All images were analyzed by two musculoskeletal radiologists identifying and grading cartilage, meniscal, ligamentous. and other knee abnormalities with WORMS scores. Meniscal segmentation was performed to generate T1rho and T2 maps in six compartments. No differences in morphological knee abnormalities were found before and after the marathon. However, all marathon runners showed a significant increase in T1rho and T2 values after competition in all meniscus compartments (p < 0.0001), which may indicate changes in the biochemical composition of meniscal tissue. While T2 values decreased after 3 months T1rho values remained at a high level, indicating persisting changes in the meniscal matrix composition after a marathon. T2 values in menisci have the potential to be used as biomarkers for identifying reversible meniscus matrix changes indicating potential tissue damage. T1rho values need further study, but may be a valuable marker for diagnosing early, degenerative changes in the menisci following exercise. (orig.)

  18. Hot tearing studies in AA5182

    Science.gov (United States)

    van Haaften, W. M.; Kool, W. H.; Katgerman, L.

    2002-10-01

    One of the major problems during direct chill (DC) casting is hot tearing. These tears initiate during solidification of the alloy and may run through the entire ingot. To study the hot tearing mechanism, tensile tests were carried out in semisolid state and at low strain rates, and crack propagation was studied in situ by scanning electron microscopy (SEM). These experimentally induced cracks were compared with hot tears developed in an AA5182 ingot during a casting trial in an industrial research facility. Similarities in the microstructure of the tensile test specimens and the hot tears indicate that hot tearing can be simulated by performing tensile tests at semisolid temperatures. The experimental data were compared with existing hot tearing models and it was concluded that the latter are restricted to relatively high liquid fractions because they do not take into account the existence of solid bridges in the crack.

  19. Classification and localization of acetabular labral tears

    International Nuclear Information System (INIS)

    Blankenbaker, D.G.; De Smet, A.A.; Keene, J.S.; Fine, J.P.

    2007-01-01

    The purpose of this study was to compare the findings on hip MR arthrography (MRA) with the published MRA and arthroscopic classifications of hip labral tears and to evaluate a clock-face method for localizing hip labral tears. We retrospectively reviewed 65 hip MRA studies with correlative hip arthroscopies. Each labrum was evaluated on MRA using the classification system of Czerny and an MRA modification of the Lage arthroscopic classification. In addition, each tear was localized on MRA by using a clock-face description where 6 o'clock was the transverse ligament and 3 o'clock was anterior. These MRA findings were then correlated with the arthroscopic findings using the clock-face method of localization and the Lage arthroscopic classification of labral tears. At MRA, there were 42 Czerny grade 2 and 23 grade 3 labral tears and 22 MRA Lage type 1, 11 type 2, 22 type 3 and 10 type 4 tears. At arthroscopy, there were 10 Lage type 1 flap tears, 20 Lage type 2 fibrillated tears, 18 Lage type 3 longitudinal peripheral tears and 17 Lage type 4 unstable tears. The Czerny MRA classification and the modified MRA Lage classification had borderline correlation with the arthroscopic Lage classification. Localization of the tears using a clock-face description was within 1 o'clock of the arthroscopic localization of the tears in 85% of the patients. The Lage classification, which is the only published arthroscopic classification system for hip labral tears, does not correlate well with the Czerny MRA or an MRA modification of the Lage classification. Using a clock-face description to localize tears provides a way to accurately localize a labral tear and define its extent. (orig.)

  20. Determination of p-y Curves for Bucket Foundations in Silt and Sand Using Finite Element Modelling

    DEFF Research Database (Denmark)

    Vethanayagam, Vinojan; Ibsen, Lars Bo

    slender than the tested piles. The suction bucket has a slenderness ratio of 0.5-1, thus its response is a rigid movement, where slender piles undergoes a flexible movement. Due to the importance of precise estimations, p-y formulations for suction buckets in drained and undrained silt are sought...... developed with use of finite element. In general the developed p-y formulations for the drained and undrained silt are fairly precise. Furthermore, the same method and basic formulation of the drained silt is applied to data of the drained sand from Østergaard et al. [2015]. The developed formulation...... herefore shows to be more versatile and precise than the formulation suggested by Østergaard et al. [2015]. The developed p-y formulations are functions of the effective vertical in-situ stress, soil stiffness, diameter of the bucket and the internal friction angle/the undrained shear strength....

  1. Dynamic behaviour of mono bucket foundations subjected to combined transient loading

    DEFF Research Database (Denmark)

    Nielsen, Søren Dam; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl

    2015-01-01

    This article presents the results from small scale testing, investigating the effect of transient combined loading of a bucketfoundation. The tests are performed inside a pressure tank at Aalborg University, Denmark. The bucket foundation was installed in dense water saturated sand and transient ...

  2. Material Composition of Bucket Foundation Transition Piece for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Nezhentseva, Anastasia; Andersen, Lars; Ibsen, Lars Bo

    2010-01-01

    In Denmark, production of renewable energy is focused on offshore wind turbines, since they make little if any inconvenience for residents in inhabited areas. High requirements are placed on the installation of the foundations which can cost about 30% of the total cost of the wind turbine....... This paper deals with the transition piece for a relatively novel type of foundation, the so-called suction bucket (caisson), focusing on the design of a transition piece connecting the turbine column with a suction bucket used as a monopod foundation for an offshore wind turbine. Since the current design...... practice is limited to the use of steel-flange-reinforced shear panels for the transition piece—a production that requires extensive welding work—a desirable solution is to find a material that provides lower cost and easier manufacturing without compromising the strength and stiffness. The paper compares...

  3. Tearing mode saturation with finite pressure

    International Nuclear Information System (INIS)

    Lee, J.K.

    1988-01-01

    With finite pressure, the saturation of the current-driven tearing mode is obtained in three-dimensional nonlinear resistive magnetohydrodynamic simulations for Tokamak plasmas. To effectively focus on the tearing modes, the perturbed pressure effects are excluded while the finite equilibrium pressure effects are retained. With this model, the linear growth rates of the tearing modes are found to be very insensitive to the equilibrium pressure increase. The nonlinear aspects of the tearing modes, however, are found to be very sensitive to the pressure increase in that the saturation level of the nonlinear harmonics of the tearing modes increases monotonically with the pressure rise. The increased level is associated with enhanced tearing island sizes or increased stochastic magnetic field region. (author)

  4. [The correlations between corneal sensation, tear meniscus volume, and tear film osmolarity after femtosecond laser-assisted LASIK].

    Science.gov (United States)

    Zhang, Luyan; Sun, Xiyu; Yu, Ye; Xiong, Yan; Cui, Yuxin; Wang, Qinmei; Hu, Liang

    2016-01-01

    To investigate the correlations between corneal sensation, tear meniscus volume, and tear film osmolarity after femtosecond laser-assisted LASIK (FS-LASIK) surgery. In this prospective clinical study, 31 patients undergoing FS-LASIK for myopia were recruited. The upper and lower tear meniscus volumes (UTMV and LTMV) were measured by customized anterior segment optical coherence tomography, tear film osmolarity was measured by a TearLab Osmolarity test device, central corneal sensation was measured by a Cochet-Bonner esthesiometer preoperatively, at 1 week, 1 and 3 months postoperatively. Repeated measures analysis of variance was used to evaluate whether the tear film osmolarity, tear meniscus volume, and corneal sensation were changed after surgery. The correlations between these variables were analyzed by the Pearson correlation analysis. The tear film osmolarity was (310.03 ± 16.48) mOsms/L preoperatively, (323.51 ± 15.92) mOsms/L at 1 week, (319.93 ± 14.27) mOsms/L at 1 month, and (314.97±12.91) mOsms/L at 3 months. The UTMV was (0.42±0.15), (0.25± 0.09), (0.30±0.11), and (0.35±0.09) μL, respectively; the LTMV was (0.60±0.21),(0.37±0.08), (0.44± 0.14), and (0.52±0.17) μL, respectively. The tear film osmolarity was significantly higher at 1 week and 1 month postoperatively compared with the baseline (P=0.001, 0.004), and reduced to the preoperative level at 3 months (P=0.573). The UTMV, LTMV, and corneal sensation values presented significant decreases at all postoperative time points (all Psensation at 1 week after surgery (r=0.356,P=0.005). There were significant correlations between the preoperative LTMV and corneal sensation at 1 week, 1 and 3 months (respectively, r=0.422, 0.366, 0.352;P=0.001, 0.004, 0.006). No significant correlations were found between the tear film osmolarity, tear meniscus volume, and corneal sensation after surgery (all P>0.05). The tear film osmolarity, tear meniscus volume, and corneal sensation became aggravated due

  5. Test Procedure for Axially Loaded Bucket Foundations in Sand (Large Yellow Box)

    DEFF Research Database (Denmark)

    Vaitkunaite, Evelina

    This is a practical guide for preparing the soil, running a CPT test, installing a scaled bucket foundation model and running a test in the large yellow sand box cos(Kristina) in the geotechnical laboratory at Aalborg University. The test procedure is used for the examination of statically...... and cyclically axially loaded bucket foundation model In dense sand. The foundation model in scale of approximately 1:10 compared to the prototype size. The guide describes the step-by-step procedure for tests with and without surface pressure. A detailed description of test setup using the large yellow sand box...... for a monopile testing was provided by Thomassen (2015a), procedure for monopile testing can be found in Thomassen (2015b), while safety instructions were given by Vaitkunaite et al. (2014)....

  6. Energy Bucket: A Tool for Power Profiling and Debugging of Sensor Nodes

    DEFF Research Database (Denmark)

    Andersen, Jacob; Hansen, Morten Tranberg

    2009-01-01

    The ability to precisely measure and compare energy consumption and relate this to particular parts of programs is a recurring theme in sensor network research. This paper presents the Energy Bucket, a low-cost tool designed for quick empirical measurements of energy consumptions across 5 decades...... of current draw. The Energy Bucket provides a light-weight state API for the target system, which facilitates easy scorekeeping of energy consumption between different parts of a target program. We demonstrate how this tool can be used to discover programming errors and debug sensor network applications.......Furthermore, we show how this tool, together with the target system API, offers a very detailed analysis of where energy is spent in an application, which proves to be very useful when comparing alternative implementations or validating theoretical energy consumption models....

  7. Percentage Level of Tannin fur Rabbit for Leather Concerning Stitch Tearing Strength, Tearing Strength and Flexibility

    OpenAIRE

    Mustakim Mustakim; Aris Sri Widati; Lisa Purnaningtyas

    2012-01-01

    The purpose of this study was to find out the appropriate of tannin level for rabbit fur leather concerning stitch tearing strength, tearing strength, and flexibility. The result were expected to contribute good information for the society, leather craftsman, and further researchers about fur leather tanning especially rabbit fur leather with tannin concerning stitch tearing strength, tearing strength and flexibility. The material that used were 12 pieces of four months of rabbit skin. The re...

  8. Interaction of tearing modes

    International Nuclear Information System (INIS)

    Satya, Y.; Schmidt, G.

    1979-01-01

    A fully developed tearing mode modifies the magnetic field profile. The effect of this profile modification on the linear growth rate of a different tearing mode in a slab and cylindrical geometry is investigated

  9. Biomechanical testing of new meniscal repair techniques containing ultra high-molecular weight polyethylene suture.

    Science.gov (United States)

    Barber, F Alan; Herbert, Morley A; Schroeder, F Alexander; Aziz-Jacobo, Jorge; Sutker, Michael J

    2009-09-01

    To evaluate the biomechanical characteristics of current meniscal repair techniques containing ultra high-molecular weight polyethylene (UHMWPE) suture with and without cyclic loading. Vertical longitudinal cuts made in porcine menisci were secured with a single repair device. Noncycled and cycled (500 cycles) biomechanical tests were performed on the following groups: group 1, No. 2-0 Mersilene vertical suture (Ethicon, Somerville, NJ); group 2, No. 2-0 Orthocord vertical suture (DePuy Mitek, Westwood, MA); group 3, No. 0 Ultrabraid vertical suture (Smith & Nephew Endoscopy, Andover, MA); group 4, No. 2-0 FiberWire vertical suture (Arthrex, Naples, FL); group 5, vertically oriented mattress suture by use of an Ultra FasT-Fix device (Smith & Nephew Endoscopy) with No. 0 Ultrabraid; group 6, vertically oriented mattress suture by use of a RapidLoc A2 device (DePuy Mitek) with No. 2-0 Orthocord suture; group 7, vertically oriented stitch by use of a MaxFire device with MaxBraid PE suture (Biomet Sports Medicine, Warsaw, IN); and group 8, an obliquely oriented stitch of No. 0 UHMWPE suture inserted by use of a CrossFix device (Cayenne Medical, Scottsdale, AZ). Endpoints were failure loads, failure modes, stiffness, and cyclic displacement. Mean single-pull loads were calculated for Ultra FasT-Fix (121 N), FiberWire (110 N), MaxFire (130 N), Mersilene (84 N), Orthocord (124 N), RapidLoc A2 (86 N), CrossFix (77 N), and Ultrabraid (109 N). After 500 cyclic loads, the Orthocord (222 N) repair was stronger than the others: Ultra FasT-Fix (110 N), FiberWire (117 N), MaxFire (132 N), Mersilene (89 N), RapidLoc A2 (108 N), CrossFix (95 N), and Ultrabraid (126 N) (P Fix, RapidLoc A2, and MaxFire) were comparable to the isolated UHMWPE-containing suture repairs on single-failure load testing. UHMWPE-containing suture repairs are stronger than braided polyester suture repairs, but pure UHMWPE suture (Ultrabraid) elongated more during cycling. Orthocord suture is significantly

  10. Evaluation of novel biodegradable three-armed- and hyper-branched tissue adhesives in a meniscus explant model.

    Science.gov (United States)

    Bochyńska, A I; Hannink, G; Verhoeven, R; Grijpma, D W; Buma, P

    2017-05-01

    Current treatment methods to repair meniscal tears do not bring fully satisfactory results. Tissue adhesives are considered promising alternatives, since they are easy to apply and cause minimal tissue trauma. The first aim of this study was to analyze the adhesive properties of and tissue response to two recently developed biodegradable block copolymeric three-armed- and hyper-branched tissue adhesives. The second aim was to investigate if tissue surface modification with collagenase improves the attachment of the adhesives and increases the healing potential of the tissue. Cylindrical explants were harvested from bovine menisci. The central core of the explants was removed and glued back into the defect, with or without incubation in collagenase solution prior to gluing, using one of the novel glues, Dermabond® or fibrin glue. The repair constructs were cultured in vitro for 1 and 28 days. Adhesion tests and histology were performed to analyze the effects of the glue in combination with the additional treatment. The adhesive strength of the novel glues was 40-50 kPa, which was significantly higher than that of fibrin glue (15 kPa). Cells were present in direct contact with the glues, and the tissue remained vital during the whole culture period. Increased cellularity around the tear in the collagenase treated explants was observed after 1 day. The two newly developed tissue adhesives are attractive materials to be used for repair of meniscal tears. The beneficial influence of collagenase treatment in treating meniscal tears with glues still needs to be confirmed in more clinical relevant studies. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1405-1411, 2017. © 2017 Wiley Periodicals, Inc.

  11. Experimental damping assessment of a full scale offshore mono bucket foundation

    DEFF Research Database (Denmark)

    Gres, Szymon; Fejerskov, Morten; Ibsen, Lars Bo

    2016-01-01

    This paper quantifies the system damping of a offshore meteorological mast supported by a Mono Bucket foundation based on a long-term experimental campaign. The structure is located at Dogger Bank west, North Sea, and equipped with a measurement system monitoring acceleration, strain, inclination...

  12. Turbine bucket for use in gas turbine engines and methods for fabricating the same

    Science.gov (United States)

    Garcia-Crespo, Andres

    2014-06-03

    A turbine bucket for use with a turbine engine. The turbine bucket includes an airfoil that extends between a root end and a tip end. The airfoil includes an outer wall that defines a cavity that extends from the root end to the tip end. The outer wall includes a first ceramic matrix composite (CMC) substrate that extends a first distance from the root end to the tip end. An inner wall is positioned within the cavity. The inner wall includes a second CMC substrate that extends a second distance from the root end towards the tip end that is different than the first distance.

  13. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... more useful in identifying bone and joint injuries (e.g., meniscal and ligament tears in the knee, ... or suggestion into the following text box: Comment: E-mail: Area code: Phone no: Thank you! Do ...

  14. O'Donoghue's triad: magnetic resonance imaging evidence

    International Nuclear Information System (INIS)

    Staron, R.B.; Haramati, N.; Feldman, F.; Kiernan, H.A.; Pfaff, H.C.; Rubin, S.J.; Zwass, A.

    1994-01-01

    The objective was to search for magnetic resonance imaging evidence of medial collateral ligament (MCL) injury in knees with proven tears of the anterior cruciate ligament (ACL) and medial meniscus; the three abnormalities that make up O'Donoghue's triad. Although the MCL injury can be unapparent clinically, knee joint stability may be compromised. The superficial portion of the MCL was evaluated on 19 MR studies of 16 knees with arthroscopically proven ACL and medial meniscal tears. MCL thicknesses were compared to those on MR images of 19 normal knees. The injured knees were of 13 men and 3 women, ranging in age from 19 to 56 years; the normal knees were of 10 men and 9 women, ranging in age from 19 to 55 years. The medial collateral ligaments of all injured knees were abnormal, and, as a group, they had greater thicknesses and more intraligamentous thickness variability than normal knees. The MR appearance of both ACL and medial meniscal tears served as indirect evidence of MCL injury, with irregular MCL thickening indicative of prior injury. (orig.)

  15. Assessment of tear film osmolarity using the TearLab™ osmometer in normal dogs and dogs with keratoconjunctivitis sicca.

    Science.gov (United States)

    Sebbag, Lionel; Park, Shin Ae; Kass, Philip H; Maggs, David J; Attar, Mayssa; Murphy, Christopher J

    2017-07-01

    To evaluate repeatability and reproducibility of tear osmolarity measured using the TearLab ™ osmometer in normal dogs and to assess its diagnostic potential in dogs with keratoconjunctivitis sicca (KCS). Beagle dogs; six normal and five with KCS. Tear osmolarity and Schirmer tear test-1 (STT-1) values were obtained at various times. Normal dogs were assessed for diurnal variation and repeatability and reproducibility of measurements. Dogs with KCS were evaluated before and after 5 months' topical twice-daily therapy with 2% cyclosporine. Mean ± SD tear osmolarity (mOsm/L) was significantly higher in normal dogs (337.4 ± 16.2) than in dogs with KCS before therapy (306.2 ± 18.0; P dogs, tear osmolarity readings were stable during the daytime (P = 0.99). Repeated measurements revealed high variability and typically poor-to-moderate repeatability and reproducibility, although this was improved by taking three successive measurements at each session. Considering combined data from all dogs, a positive correlation existed between STT-1 and tear osmolarity measurements (Pearson's correlation test, P = 0.04, r = 0.62). Canine tear osmolarity as determined by TearLab ™ osmometer was variable, required multiple readings to be informative, and differed from values reported for humans. Dogs with KCS had a lower tear osmolarity than did normal dogs, and this increased following cyclosporine therapy. © 2016 American College of Veterinary Ophthalmologists.

  16. The contribution of 3D quantitative meniscal and cartilage measures to variation in normal radiographic joint space width—Data from the Osteoarthritis Initiative healthy reference cohort

    International Nuclear Information System (INIS)

    Roth, Melanie; Wirth, Wolfgang; Emmanuel, Katja; Culvenor, Adam G.; Eckstein, Felix

    2017-01-01

    Objective: To explore to what extent three-dimensional measures of the meniscus and femorotibial cartilage explain the variation in medial and lateral femorotibial radiographic joint space width (JSW), in healthy men and women. Methods: The right knees of 87 Osteoarthritis Initiative healthy reference participants (no symptoms, radiographic signs or risk factors of osteoarthritis; 37 men, 50 women; age 55.0 ± 7.6; BMI 24.4 ± 3.1) were assessed. Quantitative measures of subregional femorotibial cartilage thickness and meniscal position and morphology were computed from segmented magnetic resonance images. Minimal and medial/lateral fixed-location JSW were determined from fixed-flexion radiographs. Correlation and regression analyses were used to explore the contribution of demographic, cartilage and meniscal parameters to JSW in healthy subjects. Results: The correlation with (medial) minimal JSW was somewhat stronger for cartilage thickness (0.54 ≤ r ≤ 0.67) than for meniscal (−0.31 ≤ r ≤ 0.50) or demographic measures (−0.15 ≤ r ≤ 0.48), in particular in men. In women, in contrast, the strength of the correlations of cartilage thickness and meniscal measures with minimal JSW were in the same range. Fixed-location JSW measures showed stronger correlations with cartilage thickness (r ≥ 0.68 medially; r ≥ 0.59 laterally) than with meniscal measures (r ≤ |0.32| medially; r ≤ |0.32| laterally). Stepwise regression models revealed that meniscal measures added significant independent information to the total variance explained in minimal JSW (adjusted multiple r 2 = 58%) but not in medial or lateral fixed-location JSW (r 2 = 60/51%, respectively). Conclusions: In healthy subjects, minimal JSW was observed to reflect a combination of cartilage and meniscal measures, particularly in women. Fixed-location JSW, in contrast, was found to be dominated by variance in cartilage thickness in both men and women, with somewhat higher correlations between

  17. Danish translation and validation of the International Skin Tear Advisory Panel Skin Tear Classification System

    DEFF Research Database (Denmark)

    Skiveren, J; Bermark, S; LeBlanc, K

    2015-01-01

    OBJECTIVE: The aim of this study was to translate, validate and establish reliability of the International Skin Tear Classification System in Danish. METHOD: Phase 1 of the project involved the translation of the International Skin Tear Advisory Panel (ISTAP) Skin Tear Classification System......) and social and health-care assistants (non-RN) from both primary health care and a Danish university hospital in Copenhagen. Thirty photographs, with equal representation of the three types of skin tears, were selected to test validity. The photographs chosen were those originally used for internal...... and external validation by the ISTAP group. The subjects were approached in their place of work and invited to participate in the study and to attend an educational session related to skin tears. RESULTS: The Danish translation of the ISTAP classification system was tested on 270 non-wound specialists...

  18. Clinical and radiographic outcomes of meniscus surgery and future targets for biologic intervention: A review of data from the MOON Group.

    Science.gov (United States)

    Westermann, Robert W; Jones, Morgan; Wasserstein, David; Spindler, Kurt P

    Meniscus injury and treatment occurred with the majority of anterior cruciate ligament reconstructions (ACLR) in the multicenter orthopedic outcomes (MOON) cohort. We describe the patient-reported outcomes, radiographic outcomes, and predictors of pain from meniscus injuries and treatment in the setting of ACLR. Patient-reported outcomes improve significantly following meniscus repair with ACLR, but differences exist based on the meniscus injury laterally (medial or lateral). Patients undergoing medial meniscus repair have worse patient-reported outcomes and more pain compared to those with uninjured menisci. However, lateral meniscal tears can be repaired with similar outcomes as uninjured menisci. Medial meniscal treatment (meniscectomy or repair) results in a significant loss of joint space at 2 years compared to uninjured menisci. Menisci treated with excision had a greater degree of joint space loss compared to those treated with repair. Clinically significant knee pain is more common following injuries to the medial meniscus and increased in patients who undergo early re-operation after initial ACLR. Future research efforts aimed at improving outcomes after combined ACLR and meniscus treatment should focus on optimizing biologic and mechanical environments that promote healing of medial meniscal tears sustained during ACL injury.

  19. Linear stability of tearing modes

    International Nuclear Information System (INIS)

    Cowley, S.C.; Kulsrud, R.M.; Hahm, T.S.

    1986-05-01

    This paper examines the stability of tearing modes in a sheared slab when the width of the tearing layer is much smaller than the ion Larmor radius. The ion response is nonlocal, and the quasineutrality retains its full integal form. An expansion procedure is introduced to solve the quasineutrality equation in powers of the width of the tearing layer over the ion Larmor radius. The expansion procedure is applied to the collisionless and semi-collisional tearing modes. The first order terms in the expansion we find to be strongly stabilizing. The physics of the mode and of the stabilization is discussed. Tearing modes are observed in experiments even though the slab theory predicts stability. It is proposed that these modes grow from an equilibrium with islands at the rational surfaces. If the equilibrium islands are wider than the ion Larmor radius, the mode is unstable when Δ' is positive

  20. Use of midlatitude soil moisture and meteorological observations to validate soil moisture simulations with biosphere and bucket models

    Science.gov (United States)

    Robock, Alan; Vinnikov, Konstantin YA.; Schlosser, C. Adam; Speranskaya, Nina A.; Xue, Yongkang

    1995-01-01

    Soil moisture observations in sites with natural vegetation were made for several decades in the former Soviet Union at hundreds of stations. In this paper, the authors use data from six of these stations from different climatic regimes, along with ancillary meteorological and actinometric data, to demonstrate a method to validate soil moisture simulations with biosphere and bucket models. Some early and current general circulation models (GCMs) use bucket models for soil hydrology calculations. More recently, the Simple Biosphere Model (SiB) was developed to incorporate the effects of vegetation on fluxes of moisture, momentum, and energy at the earth's surface into soil hydrology models. Until now, the bucket and SiB have been verified by comparison with actual soil moisture data only on a limited basis. In this study, a Simplified SiB (SSiB) soil hydrology model and a 15-cm bucket model are forced by observed meteorological and actinometric data every 3 h for 6-yr simulations at the six stations. The model calculations of soil moisture are compared to observations of soil moisture, literally 'ground truth,' snow cover, surface albedo, and net radiation, and with each other. For three of the stations, the SSiB and 15-cm bucket models produce good simulations of seasonal cycles and interannual variations of soil moisture. For the other three stations, there are large errors in the simulations by both models. Inconsistencies in specification of field capacity may be partly responsible. There is no evidence that the SSiB simulations are superior in simulating soil moisture variations. In fact, the models are quite similar since SSiB implicitly has a bucket embedded in it. One of the main differences between the models is in the treatment of runoff due to melting snow in the spring -- SSiB incorrectly puts all the snowmelt into runoff. While producing similar soil moisture simulations, the models produce very different surface latent and sensible heat fluxes, which

  1. The relationship between the MRI features of mild osteoarthritis in the patellofemoral and tibiofemoral compartments of the knee

    International Nuclear Information System (INIS)

    Kornaat, Peter R.; Watt, Iain; Bloem, Johan L.; Riyazi, Naghmeh; Kloppenburg, Margreet

    2005-01-01

    The aim of this work was to demonstrate the relationship between osteoarthritic changes seen on magnetic resonance (MR) images of the patellofemoral (PF) or tibiofemoral (TF) compartments in patients with mild osteoarthritis (OA) of the knee. MR images of the knee were obtained in 105 sib pairs (210 patients) who had been diagnosed with OA at multiple joints. Entry criteria included that the degree of OA in the knee examined should be between a Kellgren and Lawrence score of 2 or 3. MR images were analyzed for the presence of cartilaginous lesions, bone marrow edema (BME) and meniscal tears. The relationship between findings in the medial and lateral aspects of the PF and TF compartments was examined. The number of cartilaginous defects on either side of the PF compartment correlated positively with number of cartilaginous defects in the ipsilateral TF compartment (odds ratio, OR, 55, confidence interval, CI, 7.8-382). The number of cartilaginous defects in the PF compartment correlated positively with ipsilateral meniscal tears (OR 3.7, CI 1.0-14) and ipsilateral PF BME (OR 17, CI 3.8-72). Cartilaginous defects in the TF compartment correlated positively with ipsilateral meniscal tears (OR 9.8, CI 2.5-38) and ipsilateral TF BME (OR 120, CI 6.5-2,221). Osteoarthritic defects lateralize or medialize in the PF and TF compartments of the knee in patients with mild OA. (orig.)

  2. The relationship between the MRI features of mild osteoarthritis in the patellofemoral and tibiofemoral compartments of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Kornaat, Peter R.; Watt, Iain; Bloem, Johan L. [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Riyazi, Naghmeh; Kloppenburg, Margreet [Leiden University Medical Center, Department of Rheumatology, Leiden (Netherlands)

    2005-08-01

    The aim of this work was to demonstrate the relationship between osteoarthritic changes seen on magnetic resonance (MR) images of the patellofemoral (PF) or tibiofemoral (TF) compartments in patients with mild osteoarthritis (OA) of the knee. MR images of the knee were obtained in 105 sib pairs (210 patients) who had been diagnosed with OA at multiple joints. Entry criteria included that the degree of OA in the knee examined should be between a Kellgren and Lawrence score of 2 or 3. MR images were analyzed for the presence of cartilaginous lesions, bone marrow edema (BME) and meniscal tears. The relationship between findings in the medial and lateral aspects of the PF and TF compartments was examined. The number of cartilaginous defects on either side of the PF compartment correlated positively with number of cartilaginous defects in the ipsilateral TF compartment (odds ratio, OR, 55, confidence interval, CI, 7.8-382). The number of cartilaginous defects in the PF compartment correlated positively with ipsilateral meniscal tears (OR 3.7, CI 1.0-14) and ipsilateral PF BME (OR 17, CI 3.8-72). Cartilaginous defects in the TF compartment correlated positively with ipsilateral meniscal tears (OR 9.8, CI 2.5-38) and ipsilateral TF BME (OR 120, CI 6.5-2,221). Osteoarthritic defects lateralize or medialize in the PF and TF compartments of the knee in patients with mild OA. (orig.)

  3. Arthroscopic repair of large U-shaped rotator cuff tears without margin convergence versus repair of crescent- or L-shaped tears.

    Science.gov (United States)

    Park, Jin-Young; Jung, Seok Won; Jeon, Seung-Hyub; Cho, Hyoung-Weon; Choi, Jin-Ho; Oh, Kyung-Soo

    2014-01-01

    For large-sized tears of the rotator cuff, data according to the tear shape have not yet been reported for repair methodology, configuration, and subsequent integrity. The retear rate after the repair of large mobile tears, such as crescent- or L-shaped tears, is believed to be lower compared with retear rates after the repair of large U-shaped tears that are accompanied by anterior or posterior leaves of the rotator cuff. Cohort study; Level of evidence, 3. Data were collected and analyzed from 95 consecutive patients with a large-sized rotator cuff tear who underwent arthroscopic suture-bridge repair. Patients were divided into 2 groups: those having crescent- or L-shaped tears (mobile tear group, 53 patients) and those having U-shaped tears (U-shaped tear group, 42 patients). The integrity of the repaired constructs was determined by ultrasonography at 4.5, 12, and 24 months. Moreover, clinical evaluations were performed by using the Constant score, the American Shoulder and Elbow Surgeons (ASES) score, and muscle strength at intervals of 3, 6, 12, and 24 months postoperatively. On ultrasonography at 4.5, 12, and 24 months, a retear was detected in 6, 2, and 1 patients in the mobile tear group and in 5, 2, and 1 patients in the U-shaped tear group, respectively. Significant differences in retear rates were not detected between the groups overall or at each time point. Moreover, clinical scores were similar between groups, except for the presence of a temporarily higher Constant score at 12 months in the mobile tear group. With regard to shoulder strength, between-group comparisons indicated no statistically significant difference, either in abduction or external rotation, except for the presence of temporarily higher external rotation strength at 3 months in the mobile tear group. Arthroscopic repair of large-sized rotator cuff tears yielded substantial improvements in shoulder function, regardless of tear retraction, during midterm follow-up. Moreover, the

  4. Pathological fracture of the manubrium sternum of unknown aetiology

    African Journals Online (AJOL)

    Kathryn van Boom

    during which time he experienced pain over the left anterior third and ... consisted of a solitary medial meniscal tear of the right knee ... healing fracture site, and the investigations revealed no evidence of a tumour or structural abnormality.

  5. A review on hot tearing of magnesium alloys

    Directory of Open Access Journals (Sweden)

    Jiangfeng Song

    2016-09-01

    Full Text Available Hot tearing is often a major casting defect in magnesium alloys and has a significant impact on the quality of their casting products. Hot tearing of magnesium alloys is a complex solidification phenomenon which is still not fully understood, it is of great importance to investigate the hot tearing behaviour of magnesium alloys. This review attempts to summarize the investigations on hot tearing of magnesium alloys over the past decades. The hot tearing criteria including recently developed Kou's criterion are summarized and compared. The numeric simulation and assessing methods of hot tearing, factors influencing hot tearing, and hot tearing susceptibility (HTS of magnesium alloys are discussed.

  6. MR imaging of the knee

    International Nuclear Information System (INIS)

    Djukic, S.; Melnikoff, S.; Genant, H.K.

    1990-01-01

    Artificial neural networks (ANNs) have been shown to be useful in the area of pattern recognition for medical imaging. This paper investigates whether an ANN system can accurately classify meniscal tears on MR images of the knee. Thirty-five patients were selected for either definite meniscal tear (grade III) or normal meniscus (grade O) on MR images. The images were digitized using a high-resolution image scanner (Truvel) and then archived on disk. A two-dimensional fast Fourier transform of the image was computed, and a 15-band wedge-ring filter was applied to the output. The results were used as input to a three-layer back-propagation network. After successfully training the ANN on a portion of the data base (16 cases) with an accuracy error of less than 1%, the remainder of the data was applied

  7. Rotator cuff tears: correlation between geometric tear patterns on MRI and arthroscopy and pre- and postoperative clinical findings.

    Science.gov (United States)

    Sela, Yaron; Eshed, Iris; Shapira, Shachar; Oran, Ariel; Vogel, Guy; Herman, Amir; Perry Pritsch, Moshe

    2015-02-01

    Magnetic resonance imaging (MRI) is considered to be the best non-invasive procedure for the evaluation of rotator cuff (RC) tendon tears. Burkhart's classification is a geometric classification of full-thickness RC tears on MRI. To correlate MRI and arthroscopic geometric full-thickness RC tears according to the Burkhart's classification with pre- and postoperative clinical findings. Patients who underwent arthroscopic RC repair between 2006 and 2010 were retrospectively evaluated. Preoperative MRI and arthroscopic surgical reports were reviewed for tear geometry (Burkhart's) by three (1 radiologist, 2 surgeons) and two (surgeons) readers. MRIs were also evaluated for tear size and change of tear size in successive sagittal sections and for muscle mass and fatty infiltration. Clinical examinations were performed preoperatively and at least 12 months afterwards. Postoperative function questionnaires were filled in by the patients. Forty-six patients (35 men, 11 women; mean age, 57 years; range, 41-72 years) were evaluated. Tears depicted on MRIs were classified as crescent in 11 patients (24%), longitudinal in three (6.5%), massive contracted in 29 (63%), and cuff arthropathy in three (6.5%). Muscle changes were noted almost exclusively in patients with massive tears and cuff arthropathy (16/32 patients, P = 0.013). MRIs and arthroscopic geometric classifications were in close agreement. Tear type did not correlate with pre- and postoperative physical examination or with postoperative clinical questionnaires scores. Geometric RC tear characterizations on preoperative MRIs were closely associated with arthroscopic findings. Postoperative results were not affected by the geometric pattern of the tears. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  8. Delay in surgery predisposes to meniscal and chondral injuries in anterior cruciate ligament deficient knees

    Directory of Open Access Journals (Sweden)

    Ravi Gupta

    2016-01-01

    Conclusion: Surgical delay predicts an increase in medial meniscal and lateral articular injuries justifying early rather than delayed reconstruction in ACL deficient knees. Increasing age is positively related to intraarticular injuries while females are more susceptible to lateral articular injuries.

  9. The Bucket System – A computer mediated signaling system for group improvisation

    DEFF Research Database (Denmark)

    Dahlstedt, Palle; Nilsson, Per Anders; Robair, Gino

    2015-01-01

    The Bucket System is a new system for computer-mediated ensemble improvisation, designed by improvisers for improvisers. Coming from a tradition of structured free ensemble improvisation practices (comprovisation), influenced by post-WW2 experimental music practices, it is a signaling system...

  10. Comparison of low-abundance biomarker levels in capillary-collected nonstimulated tears and washout tears of aqueous-deficient and normal patients.

    Science.gov (United States)

    Guyette, Nicole; Williams, Larezia; Tran, My-Tho; Than, Tammy; Bradley, John; Kehinde, Lucy; Edwards, Clara; Beasley, Mark; Fullard, Roderick

    2013-05-01

    Low tear volume limits the use of nonstimulated (NS) microcapillary tear collection in aqueous-deficient (AD) patients. Adding a small amount of "washout" fluid to the eye prior to tear collection is a potentially viable alternative method for abundant proteins, but is relatively untested for low-abundance biomarkers. This study determined the feasibility of the washout (WO) method as an NS alternative for low-abundance biomarkers. NS and WO biomarker profiles were compared between AD patients and non-AD controls to determine if the two methods identify the same intergroup differences. Matching NS and WO tears were collected from 48 patients by micropipette, the WO sample after instillation of 10 μL saline. Tear cytokine levels were measured by 27-Plex Bio-Rad assay. Bland-Altman analyses for each biomarker determined the agreement between tear sample types. Patients were grouped as AD or non-AD based on Schirmer score to determine if NS profile between-group differences were preserved in WO tears. Bland-Altman plots showed good biomarker level agreement between NS and WO tears for most cytokines. Five biomarkers, among those most often cited as differing in AD dry eye, differed significantly between non-AD and AD groups in both tear types. Additional biomarker differences were seen in NS tears only. The WO tear collection method is a viable alternative to NS tears for many low-abundance biomarkers and is able to replicate major NS tear differences between dry eye groups. More subtle intergroup differences are lost in WO samples because of reduced statistical power.

  11. Warm and touching tears: tearful individuals are perceived as warmer because we assume they feel moved and touched.

    Science.gov (United States)

    Zickfeld, Janis H; Schubert, Thomas W

    2018-01-31

    Recent work investigated the inter-individual functions of emotional tears in depth. In one study (Van de Ven, N., Meijs, M. H. J., & Vingerhoets, A. (2017). What emotional tears convey: Tearful individuals are seen as warmer, but also as less competent. British Journal of Social Psychology, 56(1), 146-160. Https://doi.org/10.1111/bjso.12162) tearful individuals were rated as warmer, and participants expressed more intentions to approach and help such individuals. Simultaneously, tearful individuals were rated as less competent, and participants expressed less intention to work with the depicted targets. While tearful individuals were perceived as sadder, perceived sadness mediated only the effect on competence, but not on warmth. We argue that tearful individuals might be perceived as warm because they are perceived as feeling moved and touched. We ran a pre-registered extended replication of Van de Ven et al. Results replicate the warmth and helping findings, but not the competence and work effects. The increase in warmth ratings was completely mediated by perceiving feeling moved and touched. Possible functions of feeling moved and touched with regard to emotional tears are discussed.

  12. Comparative study of lubricating properties of tear substitutes Systane® Ultra and Visine® Clear Tears

    Directory of Open Access Journals (Sweden)

    Yu. A. Pavlova

    2014-07-01

    Full Text Available Purpose: To compare tear substitutive properties of Systane® Ultra and Visine® Clear Tears in dry eye therapy.Methods: 20 patients with dry eye due to chronic blepharoconjunctivitis and 20 patients with neurotrophic dry eye following corneal refractive surgery were examined. Treatment schedule was the following: in the first 7 days, Systane® Ultra was instilled in the right eye and Visine® Clear Tears was instilled in the left eye, while from day 8 to day 30, only one medicine selected by the patient was applied. Their efficacy was measured by tear film stability and patients’ subjective sensations.Results: Norn test results improved to day 7 in patients with dry eye following corneal refractive surgery and to day 30 in patients with dry eye due to blepharoconjunctivitis regardless of eye drops used. As to patients’ comfort, Systane® Ultra is preferable to Visine® Clear Tears.Conclusion: Systane® Ultra is therapeutically similar to but preferable to Visine® Clear Tears due to good tolerability.

  13. Comparative study of lubricating properties of tear substitutes Systane® Ultra and Visine® Clear Tears

    Directory of Open Access Journals (Sweden)

    Yu. A. Pavlova

    2013-01-01

    Full Text Available Purpose: To compare tear substitutive properties of Systane® Ultra and Visine® Clear Tears in dry eye therapy.Methods: 20 patients with dry eye due to chronic blepharoconjunctivitis and 20 patients with neurotrophic dry eye following corneal refractive surgery were examined. Treatment schedule was the following: in the first 7 days, Systane® Ultra was instilled in the right eye and Visine® Clear Tears was instilled in the left eye, while from day 8 to day 30, only one medicine selected by the patient was applied. Their efficacy was measured by tear film stability and patients’ subjective sensations.Results: Norn test results improved to day 7 in patients with dry eye following corneal refractive surgery and to day 30 in patients with dry eye due to blepharoconjunctivitis regardless of eye drops used. As to patients’ comfort, Systane® Ultra is preferable to Visine® Clear Tears.Conclusion: Systane® Ultra is therapeutically similar to but preferable to Visine® Clear Tears due to good tolerability.

  14. Tear exchange and contact lenses: a review.

    Science.gov (United States)

    Muntz, Alex; Subbaraman, Lakshman N; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  15. A new method for automated dynamic calibration of tipping-bucket rain gauges

    Science.gov (United States)

    Humphrey, M.D.; Istok, J.D.; Lee, J.Y.; Hevesi, J.A.; Flint, A.L.

    1997-01-01

    Existing methods for dynamic calibration of tipping-bucket rain gauges (TBRs) can be time consuming and labor intensive. A new automated dynamic calibration system has been developed to calibrate TBRs with minimal effort. The system consists of a programmable pump, datalogger, digital balance, and computer. Calibration is performed in two steps: 1) pump calibration and 2) rain gauge calibration. Pump calibration ensures precise control of water flow rates delivered to the rain gauge funnel; rain gauge calibration ensures precise conversion of bucket tip times to actual rainfall rates. Calibration of the pump and one rain gauge for 10 selected pump rates typically requires about 8 h. Data files generated during rain gauge calibration are used to compute rainfall intensities and amounts from a record of bucket tip times collected in the field. The system was tested using 5 types of commercial TBRs (15.2-, 20.3-, and 30.5-cm diameters; 0.1-, 0.2-, and 1.0-mm resolutions) and using 14 TBRs of a single type (20.3-cm diameter; 0.1-mm resolution). Ten pump rates ranging from 3 to 154 mL min-1 were used to calibrate the TBRs and represented rainfall rates between 6 and 254 mm h-1 depending on the rain gauge diameter. All pump calibration results were very linear with R2 values greater than 0.99. All rain gauges exhibited large nonlinear underestimation errors (between 5% and 29%) that decreased with increasing rain gauge resolution and increased with increasing rainfall rate, especially for rates greater than 50 mm h-1. Calibration curves of bucket tip time against the reciprocal of the true pump rate for all rain gauges also were linear with R2 values of 0.99. Calibration data for the 14 rain gauges of the same type were very similar, as indicated by slope values that were within 14% of each other and ranged from about 367 to 417 s mm h-1. The developed system can calibrate TBRs efficiently, accurately, and virtually unattended and could be modified for use with other

  16. Erosion of Pelton buckets and changes in turbine efficiency measured in the HPP Fieschertal

    Science.gov (United States)

    Abgottspon, A.; Staubli, T.; Felix, D.

    2016-11-01

    Geometrical changes and material loss of Pelton turbine runners as well as changes in turbine efficiency were measured at HPP Fieschertal in Valais, Switzerland. The HPP is equipped with two horizontal axis Pelton units, with each 32 MW nominal power, 7.5 m3/s design discharge, 515 m head and two injectors. The injectors and the buckets are hard-coated. Hydro-abrasive erosion was quantified based on repeated measurements on two runner buckets using (i) 3d-scanning and (ii) a coating thickness gauge. Changes in efficiency were measured by applying the sliding needle procedure. In addition to these periodically performed measurements, efficiency was also continuously monitored. The highest erosion rate was measured during the first half of the sediment season 2012 including a major sediment transport event. Because the runner was not fully reconditioned at the beginning of this season, progressive damages occurred. After the event, a splitter width of 10 mm was measured, corresponding to 1.5 % of the inner bucket width. The cut-outs were eroded by up to 9 mm towards the axis. The efficiency reductions ranged from 1 % in the year with the major sediment transport event to insignificant differences in 2014, when the sediment load was small and only little hydro-abrasive erosion occurred.

  17. Morphologic characterization of meniscal root ligaments in the human knee with magnetic resonance microscopy at 11.7 and 3 T

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Eric Y.; Chung, Christine B. [VA San Diego Healthcare System, Department of Radiology, San Diego, CA (United States); University of California, San Diego Medical Center, Department of Radiology, San Diego, CA (United States); Biswas, Reni; DiCamillo, Paul; Statum, Sheronda; Tafur, Monica; Bydder, Graeme M. [University of California, San Diego Medical Center, Department of Radiology, San Diego, CA (United States)

    2014-10-15

    To determine the feasibility of using MR microscopy to characterize the root ligaments of the human knee at both ultra-high-field (11.7 T) and high-field (3 T) strengths. Seven fresh cadaveric knees were used for this study. Six specimens were imaged at 11.7 T and one specimen at 3 T using isotropic or near-isotropic voxels. Histologic correlation was performed on the posteromedial root ligament of one specimen. Meniscal root ligament shape, signal intensity, and ultrastructure were characterized. High-resolution, high-contrast volumetric images were generated from both MR systems. Meniscal root ligaments were predominantly oval in shape. Increased signal intensity was most evident at the posteromedial and posterolateral root ligaments. On the specimen that underwent histologic preparation, increased signal intensity corresponded to regions of enthesis fibrocartilage. Collagen fascicles were continuous between the menisci and root ligaments. Predominantly horizontal meniscal radial tie fibers continued into the root ligaments as vertical endoligaments. MR microscopy can be used to characterize and delineate the distinct ultrastructure of the root ligaments on both ultra-high-field- and high-field-strength MR systems. (orig.)

  18. Recovery of lower extremity muscle strength and functional performance in middle-aged patients undergoing arthroscopic partial meniscectomy

    DEFF Research Database (Denmark)

    Ganderup, Tina; Jensen, Carsten; Holsgaard-Larsen, Anders

    2017-01-01

    PURPOSE: To investigate lower extremity muscle strength and functional performance before and after arthroscopic partial meniscectomy in middle-aged patients with degenerative meniscal tears. We hypothesized that patients would experience deficiencies in the affected leg at 3 months post-surgery,...

  19. MR imaging of the knee

    International Nuclear Information System (INIS)

    Kramer, J.

    2006-01-01

    Full text: Although assessment of internal derangements of the knee begins with clinical evaluation including careful physical examination, imaging is fundamental to accurate diagnosis of many of these derangements. MRI has become a valuable diagnostic modality for the evaluation of neoplastic, traumatic, and inflammatory disorders of the musculoskeletal system. MRI not only depicts osseous lesions, but provides information on the cartilage, menisci, ligaments and surrounding soft-tissues. The menisci of the knee are composed of fibrocartilage. Advanced degeneration is observed during aging, although it is difficult to determine which changes are age-related alone and which are caused by prior overuse of trauma. Although meniscal tears may be discovered incidentally, they may have a variety of clinical manifestations. Two categories of meniscal tears commonly are identified: traumatic and degenerative. This categorization generally is based on analysis of the clinical history, the age of the patients, and the gross morphology of the meniscus at the time of arthroscopy. Sometimes torn meniscal fragments may be displaced and lead to restriction of movement in the knee joint. MRI is the method of choice in the preoperative diagnosis of meniscal injuries of the knee. Sensitivities and specificities for meniscal tears above 95% with a negative predictive value of almost 100% are reported. In the evaluation of postoperative menisci, however, the above mentioned criteria have proved more problematic if diagnosis is uncertain, therefore, MR-arthrography seems to be a reasonable alternative to repeat arthroscopy in patients who have had surgical treatment of meniscal tears. MR imaging diagnosis of injuries to the anterior acruciate ligament is based on direct signs and abnormalities in the surrounding structures (indirect or secondary signs). The two major alterations occurring within the ligament itself are changes in this morphology or courses and changes in its signal

  20. Interferometric characterization of tear film dynamics

    Science.gov (United States)

    Primeau, Brian Christopher

    The anterior refracting surface of the eye is the thin tear film that forms on the surface of the cornea. When a contact lens is on worn, the tear film covers the contact lens as it would a bare cornea, and is affected by the contact lens material properties. Tear film irregularity can cause both discomfort and vision quality degradation. Under normal conditions, the tear film is less than 10 microns thick and the thickness and topography change in the time between blinks. In order to both better understand the tear film, and to characterize how contact lenses affect tear film behavior, two interferometers were designed and built to separately measure tear film behavior in vitro and in vivo. An in vitro method of characterizing dynamic fluid layers applied to contact lenses mounted on mechanical substrates has been developed using a phase-shifting Twyman-Green interferometer. This interferometer continuously measures light reflected from the surface of the fluid layer, allowing precision analysis of the dynamic fluid layer. Movies showing this fluid layer behavior can be generated. The fluid behavior on the contact lens surface is measured, allowing quantitative analysis beyond what typical contact angle or visual inspection methods provide. The in vivo interferometer is a similar system, with additional modules included to provide capability for human testing. This tear film measurement allows analysis beyond capabilities of typical fluorescein visual inspection or videokeratometry and provides better sensitivity and resolution than shearing interferometry methods.

  1. [Alterations in tears aqueous layer during cytostatics treatment].

    Science.gov (United States)

    Wojciechowska, Katarzyna; Wieckowska-Szakiel, Marzena; Rózalska, Barbara; Jurowski, Piotr

    2013-01-01

    The aim of the study was to evaluate tears secretion, pH and lysozyme activity in tears aqueous layer during chemotherapy in lung, breast and bowel cancer. 36 patients were enrolled to the study. Depending on the type of cancer and type of chemotherapy patients were divided into three groups. Group I (12 patients) diagnosed with non-small-cell lung cancer treated with PE schema (cisplatin, etoposide), Group II (12 patients) with breast cancer treated with FAC schema (fluorouracil, doxorubicin, cyclophosphamide), Group III (12 patients) with bowel cancer treated with FU/LV schema (fluorouracil, leucovorin). In all the patients: Schirmer's I test, pH measurements and lysozyme test were performed. Patients were examined before chemotherapy, after 2nd, 4th, 6th cycle. In group I and II lowering of tears secretion (p tears secretion (p tears film in all groups (p tears aqueous layer causing alterations of tears secretions. PH alterations depending on type of chemotherapy was observed. Lowering of lysozyme activity in tears was observed. All the deteriorations aggravate with duration of chemotherapy. Alterations of tears film parameters during chemotherapy may influence upon eye surface homeostasis and infectious complication. tears aqueous layer, Schirmer's test, lysozyme activity, tears pH.

  2. Quadriceps Strength and Endurance After Posterior Cruciate Ligament Tears Versus Matched Group With Anterior Cruciate Ligament Tears.

    Science.gov (United States)

    Lee, Dae-Hee; Han, Seung-Beom; Lee, Jin-Hyuck; Lee, Seok-Joo; Suh, Dong-Won; Jeong, Hye-Jin

    2015-06-01

    This study was designed to compare the preoperative strengths and endurances of the quadriceps and hamstring muscles in patients with anterior cruciate ligament (ACL) versus posterior cruciate ligament (PCL) tears. Quadriceps and hamstring muscle strength and endurance were compared between 20 prospectively enrolled patients with isolated PCL tears and a retrospective, matched control group of 20 patients with isolated ACL tears. The maximal torque (60°/s) and total work (180°/s) of the quadriceps and hamstring were evaluated with an isokinetic testing device. Total work (1,094.4 ± 505.8 J v 797.5 ± 332.7 J, P = .035) and peak torque (129.9 ± 56.2 N ∙ m v 98.2 ± 37.4 N ∙ m, P = .046) of the quadriceps muscle on the involved side were higher in the PCL tear group than in the ACL tear group. However, there were no significant differences between the PCL tear group and ACL tear group in hamstring muscle strength (45.8 ± 42.3 N ∙ m and 46.0 ± 24.4 N ∙ m, respectively; P = .940) and endurance (429.3 ± 238.9 J and 382.4 ± 256.1 J, respectively; P = .574) on the involved side. The strength and endurance of the quadriceps muscle of the injured limb were greater after PCL tears than after ACL tears. However, there were no significant between-group differences in hamstring muscle strength and endurance on the involved side. Level III, retrospective comparative study. Copyright © 2015 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  3. Clinical Application of Scaffolds for Partial Meniscus Replacement.

    Science.gov (United States)

    Moran, Cathal J; Withers, Daniel P; Kurzweil, Peter R; Verdonk, Peter C

    2015-09-01

    Meniscal tears are common injuries often treated by partial meniscectomy. This may result in altered joint contact mechanics which in turn may lead to worsening symptoms and an increased risk of osteoarthritis. Meniscal scaffolds have been proposed as a treatment option aimed at reducing symptoms while also potentially reducing progression of degenerative change. There are 2 scaffolds available for clinical use at the present time; Collagen Meniscus Implant and Actifit. Medium-term to long-term data (4.9 to 11.3 y) demonstrate efficacy of partial meniscus replacement. The patients who seem to benefit most are chronic postmeniscectomy rather than acute meniscal injuries. Herein we report on available clinical data for Collagen Meniscus Implant and Actifit while describing our preferred surgical technique and postoperative rehabilitation program.

  4. Meniscal tear. Diagnostic errors in MR imaging

    International Nuclear Information System (INIS)

    Barrera, M. C.; Recondo, J. A.; Gervas, C.; Fernandez, E.; Villanua, J. A.M.; Salvador, E.

    2003-01-01

    To analyze diagnostic discrepancies found between magnetic resonance (MR) and arthroscopy, and the determine the reasons that they occur. Two-hundred and forty-eight MR knee explorations were retrospectively checked. Forty of these showed diagnostic discrepancies between MR and arthroscopy. Two radiologists independently re-analyzed the images from 29 of the 40 studies without knowing which diagnosis had resulted from which of the two techniques. Their interpretations were correlated with the initial MR diagnosis, MR images and arthroscopic results. Initial errors in MR imaging were classified as either unavoidable, interpretive, or secondary to equivocal findings. Eleven MR examinations could not be checked since their corresponding imaging results could not be located. Of 34 errors found in the original diagnoses, 12 (35.5%)were classified as unavoidable, 14 (41.2%) as interpretative and 8 (23.5%) as secondary to equivocal findings. 41.2% of the errors were avoided in the retrospective study probably due to our department having greater experience in interpreting MR images, 25.5% were unavailable even in the retrospective study. A small percentage of diagnostic errors were due to the presence of subtle equivocal findings. (Author) 15 refs

  5. Tearing modes in toroidal geometry

    International Nuclear Information System (INIS)

    Connor, J.W.; Cowley, S.C.; Hastie, R.J.; Hender, T.C.; Hood, A.; Martin, T.J.

    1988-01-01

    The separation of the cylindrical tearing mode stability problem into a resistive resonant layer calculation and an external marginal ideal magnetohydrodynamic (MHD) calculation (Δ' calculation) is generalized to axisymmetric toroidal geometry. The general structure of this separation is analyzed and the marginal ideal MHD information (the toroidal generalization of Δ') required to discuss stability is isolated. This can then, in principle, be combined with relevant resonant layer calculations to determine tearing mode growth rates in realistic situations. Two examples are given: the first is an analytic treatment of toroidally coupled (m = 1, n = 1) and (m = 2, n = 1) tearing modes in a large aspect ratio torus; the second, a numerical treatment of the toroidal coupling of three tearing modes through finite pressure effects in a large aspect ratio torus. In addition, the use of a coupling integral approach for determining the stability of coupled tearing modes is discussed. Finally, the possibility of using initial value resistive MHD codes in realistic toroidal geometry to determine the necessary information from the ideal MHD marginal solution is discussed

  6. Development of bucket ion source for JFT-2M neutral beam injector

    International Nuclear Information System (INIS)

    Shibata, Takatoshi; Kazawa, Minoru; Yokoyama, Kenji; Shibuya, Toshihiro; Honda, Atsushi; Shiina, Tomio

    1987-02-01

    Detailed description is given of a new Bucket Ion Source for NBI heating experiments on JFT-2M. The source is designed to achieve the high proton ratio (∼ 80 %) as well as high power. Results of the performance test is also given. (author)

  7. The contribution of 3D quantitative meniscal and cartilage measures to variation in normal radiographic joint space width—Data from the Osteoarthritis Initiative healthy reference cohort

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Melanie, E-mail: melanie.roth@pmu.ac.at [Institute of Anatomy, Paracelsus Medical University Salzburg & Nuremberg, Strubergasse 21, 5020, Salzburg (Austria); Wirth, Wolfgang, E-mail: wolfgang.wirth@pmu.ac.at [Institute of Anatomy, Paracelsus Medical University Salzburg & Nuremberg, Strubergasse 21, 5020, Salzburg (Austria); Chondrometrics GmbH, Ulrichshöglerstrasse 23, 83404, Ainring (Germany); Emmanuel, Katja, E-mail: katja.emmanuel@icloud.com [Institute of Anatomy, Paracelsus Medical University Salzburg & Nuremberg, Strubergasse 21, 5020, Salzburg (Austria); Department of Orthopedics and Traumatology, Paracelsus Medical University, Müllner Hauptstraße 48, 5020, Salzburg (Austria); Culvenor, Adam G., E-mail: adam.culvenor@pmu.ac.at [Institute of Anatomy, Paracelsus Medical University Salzburg & Nuremberg, Strubergasse 21, 5020, Salzburg (Austria); School of Allied Health, La Trobe University, Plenty Road, Bundoora, 3086, Victoria (Australia); Eckstein, Felix, E-mail: felix.eckstein@pmu.ac.at [Institute of Anatomy, Paracelsus Medical University Salzburg & Nuremberg, Strubergasse 21, 5020, Salzburg (Austria); Chondrometrics GmbH, Ulrichshöglerstrasse 23, 83404, Ainring (Germany)

    2017-02-15

    Objective: To explore to what extent three-dimensional measures of the meniscus and femorotibial cartilage explain the variation in medial and lateral femorotibial radiographic joint space width (JSW), in healthy men and women. Methods: The right knees of 87 Osteoarthritis Initiative healthy reference participants (no symptoms, radiographic signs or risk factors of osteoarthritis; 37 men, 50 women; age 55.0 ± 7.6; BMI 24.4 ± 3.1) were assessed. Quantitative measures of subregional femorotibial cartilage thickness and meniscal position and morphology were computed from segmented magnetic resonance images. Minimal and medial/lateral fixed-location JSW were determined from fixed-flexion radiographs. Correlation and regression analyses were used to explore the contribution of demographic, cartilage and meniscal parameters to JSW in healthy subjects. Results: The correlation with (medial) minimal JSW was somewhat stronger for cartilage thickness (0.54 ≤ r ≤ 0.67) than for meniscal (−0.31 ≤ r ≤ 0.50) or demographic measures (−0.15 ≤ r ≤ 0.48), in particular in men. In women, in contrast, the strength of the correlations of cartilage thickness and meniscal measures with minimal JSW were in the same range. Fixed-location JSW measures showed stronger correlations with cartilage thickness (r ≥ 0.68 medially; r ≥ 0.59 laterally) than with meniscal measures (r ≤ |0.32| medially; r ≤ |0.32| laterally). Stepwise regression models revealed that meniscal measures added significant independent information to the total variance explained in minimal JSW (adjusted multiple r{sup 2} = 58%) but not in medial or lateral fixed-location JSW (r{sup 2} = 60/51%, respectively). Conclusions: In healthy subjects, minimal JSW was observed to reflect a combination of cartilage and meniscal measures, particularly in women. Fixed-location JSW, in contrast, was found to be dominated by variance in cartilage thickness in both men and women, with somewhat higher correlations

  8. Rotator cuff tear: A detailed update

    Directory of Open Access Journals (Sweden)

    Vivek Pandey

    2015-01-01

    Full Text Available Rotator cuff tear has been a known entity for orthopaedic surgeons for more than two hundred years. Although the exact pathogenesis is controversial, a combination of intrinsic factors proposed by Codman and extrinsic factors theorized by Neer is likely responsible for most rotator cuff tears. Magnetic resonance imaging remains the gold standard for the diagnosis of rotator cuff tears, but the emergence of ultrasound has revolutionized the diagnostic capability. Even though mini-open rotator cuff repair is still commonly performed, and results are comparable to arthroscopic repair, all-arthroscopic repair of rotator cuff tear is now fast becoming a standard care for rotator cuff repair. Appropriate knowledge of pathology and healing pattern of cuff, strong and biological repair techniques, better suture anchors, and gradual rehabilitation of postcuff repair have led to good to excellent outcome after repair. As the healing of degenerative cuff tear remains unpredictable, the role of biological agents such as platelet-rich plasma and stem cells for postcuff repair augmentation is still under evaluation. The role of scaffolds in massive cuff tear is also being probed.

  9. Evaporation-driven instability of the precorneal tear film.

    Science.gov (United States)

    Peng, Cheng-Chun; Cerretani, Colin; Braun, Richard J; Radke, C J

    2014-04-01

    Tear-film instability is widely believed to be a signature of eye health. When an interblink is prolonged, randomly distributed ruptures occur in the tear film. "Black spots" and/or "black streaks" appear in 15 to 40 s for normal individuals. For people who suffer from dry eye, tear-film breakup time (BUT) is typically less than a few seconds. To date, however, there is no satisfactory quantitative explanation for the origin of tear rupture. Recently, it was proposed that tear-film breakup is related to locally high evaporative thinning. A spatial variation in the thickness of the tear-film lipid layer (TFLL) may lead to locally elevated evaporation and subsequent tear-film breakup. We examine the local-evaporation-driven tear-film-rupture hypothesis in a one-dimensional (1-D) model for the evolution of a thin aqueous tear film overriding the cornea subject to locally elevated evaporation at its anterior surface and osmotic water influx at its posterior surface. Evaporation rate depends on mass transfer both through the coating lipid layer and through ambient air. We establish that evaporation-driven tear-film breakup can occur under normal conditions but only for higher aqueous evaporation rates. Predicted roles of environmental conditions, such as wind speed and relative humidity, on tear-film stability agree with clinical observations. More importantly, locally elevated evaporation leads to hyperosmolar spots in the tear film and, hence, vulnerability to epithelial irritation. In addition to evaporation rate, tear-film instability depends on the strength of healing flow from the neighboring region outside the breakup region, which is determined by the surface tension at the tear-film surface and by the repulsive thin-film disjoining pressure. This study provides a physically consistent and quantitative explanation for the formation of black streaks and spots in the human tear film during an interblink. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Newton’s Rotating Water Bucket: A Simple Model

    Science.gov (United States)

    2013-01-01

    surface of the water must be an equipotential relative to the sum of the gravitational and centrifugal potential energies [9].) The value of z0 can be...twisted and the bucket is then released, it begins to spin and the surface of the water acquires a paraboloidal shape. In this paper, the parabolic...adopts a curved surface . Ernst Mach, for example, postulated that the parabolic shape must be due to the existence of matter in the universe

  11. Comparison of numerical formulations for the modeling of tensile loaded suction buckets

    DEFF Research Database (Denmark)

    Sørensen, Emil Smed; Clausen, Johan Christian; Damkilde, Lars

    2017-01-01

    The tensile resistance of a suction bucket is investigated using three different numerical formulations. The first formulation utilizes the three-field u-p-U formulation accounting for solid and fluid displacements, u and U, as well as the pore-fluid pressure, p. The two other formulations compri...

  12. Development of biodegradable hyper-branched tissue adhesives for the repair of meniscus tears.

    Science.gov (United States)

    Bochyńska, A I; Van Tienen, T G; Hannink, G; Buma, P; Grijpma, D W

    2016-03-01

    Meniscus tears are one of the most commonly occurring injuries of the knee joint. Current meniscus repair techniques are challenging and do not bring fully satisfactory results. Tissue adhesives are a promising alternative, since they are easy to apply and cause minimal tissue trauma. In this study, a series of amphiphilic copolymers based on polyethylene glycol, trimethylene carbonate and citric acid were synthesized and subsequently end-functionalized with hexamethylene diisocyanate to form reactive adhesive materials. The shear adhesive strength of the networks to bovine meniscus tissue measured in a lap-shear adhesion test ranged between 20 and 80 kPa, which was better than for fibrin glue (10 kPa). The elastic modulus of the networks depended on composition and was in the same range as that of human meniscus. Cell compatibility was assessed using Alamar Blue staining after incubation of the bovine meniscus cells with different concentrations of the glues for 7 days. Cell viability was not affected after adding up to 3mg of the adhesive/mL of medium. The proposed materials are suitable candidates to be used as resorbable tissue adhesives for meniscus repair. They have excellent mechanical and adhesive properties that can be adjusted by varying the composition of the copolymers. Meniscal tears often occur and current treatment strategies do not bring fully satisfactory results. Use of biodegradable tissue adhesives would be an interesting option, but currently available adhesives are not suited due to toxicity or poor mechanical properties. Here, we describe the development of novel biodegradable, hyper-branched, adhesive copolymers. These adhesives cure upon contact with water forming flexible networks. Their adhesion to bovine meniscus tissue was significantly better than that of clinically used fibrin glue. The tensile properties of the cured networks were in the same range of values of the human meniscus. When physiologically relevant amounts were added to

  13. Joint line tenderness and McMurray tests for the detection of meniscal lesions: what is their real diagnostic value?

    Science.gov (United States)

    Galli, Marco; Ciriello, Vincenzo; Menghi, Amerigo; Aulisa, Angelo G; Rabini, Alessia; Marzetti, Emanuele

    2013-06-01

    To assess the interobserver concordance of the joint line tenderness (JLT) and McMurray tests, and to determine their diagnostic efficiency for the detection of meniscal lesions. Prospective observational study. Orthopedics outpatient clinic, university hospital. Patients (N=60) with suspected nonacute meniscal lesions who underwent knee arthroscopy. Not applicable. Patients were examined by 3 independent observers with graded levels of experience (>10y, 3y, and 4mo of practice). The interobserver concordance was assessed by Cohen-Fleiss κ statistics. Accuracy, negative and positive predictive values for prevalence 10% to 90%, positive (LR+) and negative (LR-) likelihood ratios, and the Bayesian posttest probability with a positive or negative result were also determined. The diagnostic value of the 2 tests combined was assessed by logistic regression. Arthroscopy was used as the reference test. No interobserver concordance was determined for the JLT. The McMurray test showed higher interobserver concordance, which improved when judgments by the less experienced examiner were discarded. The whole series studied by the "best" examiner (experienced orthopedist) provided the following values: (1) JLT: sensitivity, 62.9%; specificity, 50%; LR+, 1.26; LR-, .74; (2) McMurray: sensitivity, 34.3%; specificity, 86.4%; LR+, 2.52; LR-, .76. The combination of the 2 tests did not offer advantages over the McMurray alone. The JLT alone is of little clinical usefulness. A negative McMurray test does not modify the pretest probability of a meniscal lesion, while a positive result has a fair predictive value. Hence, in a patient with a suspected meniscal lesion, a positive McMurray test indicates that arthroscopy should be performed. In case of a negative result, further examinations, including imaging, are needed. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  14. Thermal effects on tearing mode saturation

    International Nuclear Information System (INIS)

    Kim, J.S.; Chu, M.S.; Greene, J.M.

    1988-01-01

    The effect of geometry on tearing modes, saturated states of tearing modes, and the thermal effect on tearing modes are presented. The configuration of current and magnetic fields are quite different in slabs and in Tokamaks. However, for any magnetic island regardless of geometry and heating conditions, at island saturation the product of resistivity and current is the same at magnetic O and X lines. The temperature perturbation effect on the nonlinear development of tearing modes is investigated. Thermal conduction along the field lines is much faster than that in the perpendicular direction, and thus the temperature profile follows the island structure. Utilizing Spitzer's conductivity relation, the temperature perturbation is modelled as helical components of resistivity. For a usual tearing mode unstable Tokamak, where shear is positive, the islands continue to grow to a larger size when the islands are cooled. When they are heated, the island sizes are reduced. The temperature perturbation can induce islands even for equilibria stable with respect to tearing modes. Again, the islands appear when cooling takes place. The equilibria with the cooled islands show enhanced field line stochasticity, thus enhanced heat transport. Therefore, thermal instability can be directly related to pressure disruptions. (author)

  15. Tear and decohesion of bovine pericardial tissue.

    Science.gov (United States)

    Tobaruela, Almudena; Elices, Manuel; Bourges, Jean Yves; Rojo, Francisco Javier; Atienza, José Miguel; Guinea, Gustavo

    2016-10-01

    The aim of this study was to evaluate quantitatively the fracture-by tear and delamination-of bovine pericardium tissues which are usually employed for the manufacture of bioprosthetic valves. A large number of samples (77) were tested in root-to-apex and circumferential directions, according to a standardised tear test (ASTM D 1938). Before performing the tear test, some samples were subjected to 1000 cycles of fatigue to a maximum stress of 3MPa. Fracture toughness of tearing and delamination were computed by following a simple fracture model. The study showed significantly lower values of delamination toughness compared with tear delamination. Moreover, tear forces were different in each test direction, revealing a clear orthotropic behaviour. All these results, as well as the testing procedure, could be of value for future research in the physiological function of pericardium tissues and clinical applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Evaluating tear clearance rate with optical coherence tomography.

    Science.gov (United States)

    Garaszczuk, Izabela K; Mousavi, Maryam; Cervino Exposito, Alejandro; Bartuzel, Maciej M; Montes-Micó, Robert; Iskander, D Robert

    2018-02-01

    To assess the early-phase of tear clearance rate (TCR) with anterior segment optical coherence tomography (OCT) and to determine the association between TCR and other clinical measures of the tear film in a group of young subjects with different levels of tear film quality. TCR was classified as the percentage decrease of subject's inferior tear meniscus height 30s after instillation of 5μl 0.9% saline solution. Fifty subjects (32F and 18M) aged (mean±standard deviation) 25.5±4.3 years volunteered for the study. It consisted of a review of medical history, Ocular Surface Disease Index (OSDI) questionnaire, tear film osmolarity measurements, slit lamp examination and TCR estimation based on dynamic measurements of the lower tear meniscus with OCT. Estimates of TCR were contrasted against subject age and tear film measures commonly used for dry eye diagnosis, which includes OSDI score, fluorescein tear film break-up time (FBUT), tear meniscus height (TMH), blinking frequency, tear film osmolarity and corneal staining. The group mean TCR was 29±13% and 36±19% respectively after 30 and 60s margin after saline solution instillation. Statistically significant correlations were found between TCR and FBUT (r 2 =0.319, placrimal functional unit. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  17. Tearing mode instability due to anomalous resistivity

    International Nuclear Information System (INIS)

    Furuya, Atsushi; Itoh, Sanae I.; Yagi, Masatoshi

    2000-01-01

    Tearing mode instability in the presence of microscopic truculence is investigates. The effects of microscopic turbulence on tearing mode are taken as drags which are calculated by one-point renormalization method and mean-field approximation. These effects are reduced to effective diffusivities in reduced MHD equations. Using these equations, the stability analyses of the tearing mode are performed. It is shown that a finite amplitude of fluctuation enhances the growth rate of tearing mode. For very high values of turbulent diffusivities, marginally stable state exists. The effects of each turbulent diffusivity on mode stability are examined near marginal stability boundary. Parameter dependence of the resistive ballooning mode turbulence on tearing mode is analyzed as an example. (author)

  18. Discoid meniscus of the knee: MR imaging

    International Nuclear Information System (INIS)

    Kim, Sung Moon; Kang, Heung Sik; Ahn, Joong Mo; Seong, Sang Cheol

    1992-01-01

    To evaluate the role of magnetic resonance (MR) imaging in the diagnosis of the discoid meniscus, the authors reviewed 31 cases of discoid menisci diagnosed by MR imaging among which 16 cases received arthroscopy. Using knee surface coil, sagittal T1, T2 and proton density images and coronal T1 weighted images were obtained with 18 cm FOV and 4 mm/ 1 mm thickness/gap. A discoid meniscus was considered if three or more contiguous sagittal images demonstrated continuity of the meniscus between the anterior and posterior horns or the diameter of the mid-portion of the meniscus exceeded 15 mm on the coronal image. The authors also observed the associated abnormalities including tears of meniscus and ligament, meniscal cyst, and osteochondral defects. All discoid menisci were lateral menisci and torn discoid lateral menisci were present in 26 cases (83%). In two cases, tears of the contralateral medial meniscus were present. The tears of anterior and posterior cruciate ligaments, meniscal cyst, and osteochondral defects were present in 4, 2, 4, and 5 cases respectively. All collateral ligaments were intact. In conclusion MR imaging was useful for the detection of discoid meniscus and associated abnormalities

  19. Two-Tunnel Transtibial Repair of Radial Meniscus Tears Produces Comparable Results to Inside-Out Repair of Vertical Meniscus Tears.

    Science.gov (United States)

    Cinque, Mark E; Geeslin, Andrew G; Chahla, Jorge; Dornan, Grant J; LaPrade, Robert F

    2017-08-01

    Radial meniscus tears disrupt the circumferential fibers and thereby compromise meniscus integrity. Historically, radial tears were often treated with meniscectomy because of an incomplete understanding of the biomechanical consequences of these tears, limited information regarding the biomechanical performance of repair, and the technical difficulty associated with repair. There is a paucity of studies on the outcomes of the repair of radial meniscus tears. Purpose/Hypothesis: The purpose was to determine the outcomes of 2-tunnel transtibial repair of radial meniscus tears and compare these results to the outcomes of patients who underwent the repair of vertical meniscus tears with a minimum of 2-year follow-up. The hypothesis was that radial and vertical meniscus tear repair outcomes were comparable. Cohort study; Level of evidence, 3. Patients who underwent 2-tunnel transtibial pullout repair for a radial meniscus tear were included in this study and compared with patients who underwent inside-out repair for a vertical meniscus tear. Subjective questionnaires were administered preoperatively and at a minimum of 2-year follow-up, including the Lysholm score, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Short Form-12 (SF-12) physical component summary (PCS), the Tegner activity scale, and patient satisfaction. Analysis of covariance was used to compare postoperative outcome scores between the meniscus repair groups while accounting for baseline scores. Adjusted mean effects relative to the radial repair group were reported with 95% CIs. Twenty-seven patients who underwent 2-tunnel transtibial pullout repair for radial meniscus tears and 33 patients who underwent inside-out repair for vertical meniscus tears were available for follow-up at a mean of 3.5 years (range, 2.0-5.4 years). No preoperative outcome score significantly differed between the groups. There were no significant group differences for any of the 2-year

  20. a comparison of accuracy of clinical tests and mri in the diagnosis of ...

    African Journals Online (AJOL)

    Methods: Between January 2011 and December 2015, 147 consecutive patients with previous history of knee injury ... Results: There was a wide variance between clinical diagnosis and MRI reportage for meniscal tears. ..... Musculoskeletal injuries associated with ... (MRI) in the management of knee disorders in a sports.

  1. Bonding of human meniscal and articular cartilage with photoactive 1,8-naphthalimide dyes

    Science.gov (United States)

    Judy, Millard M.; Nosir, Hany R.; Jackson, Robert W.; Matthews, James Lester; Lewis, David E.; Utecht, Ronald E.; Yuan, Dongwu

    1996-05-01

    This study focused on meniscal cartilage repair by using the laser-activated photoactive 1,8- naphthalimide dye N,N'-bis-{6-[2-(2-(2- aminoethoxy)ethoxy)ethoxyethyl]amino-1H-benz (de)isoquinolin-1,3(2H)-dion-2- yl}-1,11-diamino-3,6,9-trioxaundecane. Harvested cadaveric human menisci were debrided and carved into strips 1 mm thick, 10 mm long, and 3 mm wide. Each strip was divided into two flaps, the surface painted with photoactive dye, the painted surfaces overlapped, the sample wrapped in Saran film, and the composite sandwiched between two glass slides at a pressure of approximately 3 kg/cm2. The sample then was transilluminated by argon ion laser light of 457.9-nm wavelength at a power density of 200 mW/cm2 with exposure times up to 5 h (3902 J/cm2 energy density). Essentially, the same procedures were performed for human femoral articular cartilage samples. Control experiments were conducted with laser irradiation alone and with dye alone. All the specimens were stored in isotonic saline solution for 2 h after irradiation to ensure hydration. The bond shear-strength was then tested and samples prepared for optical and electron transmission microscopy. Shear strength values of up to 1.8 kg/cm2 for meniscal tissues and 1.2 kg/cm2 for articular cartilaginous tissues were obtained for exposures of 3902 J/cm2. Shear strength values of approximately 0.9 kg/cm2 and 0.4 kg/cm2, respectively, for meniscus and cartilage were obtained with 459 J/cm2 exposure. Dye- and light-only controls exhibited 0 kg/cm2 shear strength values. Microscopy revealed close contact at the bonded surface in the laser-activated, dye-treated-specimens. This study shows that the laser-activated photoactive dyes have the capability of athermally bonding the meniscal and articular cartilage surfaces.

  2. Chemosignalling effects of human tears revisited: Does exposure to female tears decrease males' perception of female sexual attractiveness?

    Science.gov (United States)

    Gračanin, Asmir; van Assen, Marcel A L M; Omrčen, Višnja; Koraj, Ivana; Vingerhoets, Ad J J M

    2017-01-01

    Gelstein et al. reported the results of three experiments suggesting a dampening influence of inhalation of female emotional tears on males' arousal and perception of female sexual attractiveness, specifically in non-sexual situations. This prompted the hypothesis that crying exerts its influence on others not only via the auditory and visual mode but also via chemosignals. In three studies, we attempted to replicate and extend Gelstein et al.'s findings by including an additional condition with irritant tears, by using pictures of sexually attractive women, and by testing related hypotheses on the pro-social effects of exposure to tears. All three studies, separately or combined in a meta-analysis, failed to replicate the original inhibitory effects of tears. In addition, sniffing tears did not affect measures of connectedness, aggression and pro-social behaviour. It is concluded that the effects of female tears on male arousal and perception of female sexual attractiveness, if any, are very weak at best. Rather, it seems that crying exerts its strong inter-personal effects through the visual and auditory sensory channels.

  3. Effectiveness of Combined Tear Film Therapy in Patients with Evaporative Dry Eye with Short Tear Film Breakup Time.

    Science.gov (United States)

    Kim, Yung Hui; Kang, Yeon Soo; Lee, Hyo Seok; Choi, Won; You, In Cheon; Yoon, Kyung Chul

    2017-10-01

    The aim of this study was to evaluate the effectiveness of combined tear film therapy targeted to aqueous, mucin, and lipid layers in patients with refractory evaporative dry eye (EDE) with short tear film breakup time (TBUT). The patients who had EDE with short TBUT and severe symptoms refractory to artificial tears were treated with hyaluronic acid (HA) 0.15% and diquafosol tetrasodium (DQS) 3% (Group 1), HA and carbomer-based lipid-containing eyedrops (Liposic EDO Gel, LPO) (Group 2), or HA, DQS, and LPO (Group 3). Ocular Surface Disease Index (OSDI) score, visual analog scale (VAS) symptom score, TBUT, Schirmer score, and corneal and conjunctival staining scores were evaluated, and noninvasive tear film breakup time (NIBUT) and tear meniscus height were measured using Keratograph ® 5 M before and 1 and 3 months after treatment. OSDI scores, VAS scores, TBUT, and NIBUT were improved at 1 and 3 months after treatment in all groups (all P film layers was most effective in improving ocular symptoms and tear film quality.

  4. Tear ferning test in healthy dogs.

    Science.gov (United States)

    Oriá, Arianne P; Raposo, Ana Claudia S; Araújo, Nayone L L C; Lima, Felipe B; Masmali, Ali M

    2017-11-07

    To evaluate and compare three tear sampling methods using two grading scales for administering the tear ferning test (TFT) to healthy dogs. In total, 90 dogs (180 eyes) were subjected to tear sampling using millimetered strips, reused after the Schirmer tear test (STT) (Schirmer group, SG). Then, the dogs were subdivided into three groups according to sampling approach: micropipette (MPG), microcapillary (MCG), and Schirmer sample 2 (S2G). The collected tears were dried on a clean microscope glass slide at room temperature and humidity. The ferning patterns were observed under a polarized light microscope and classified according to the Rolando and Masmali grading scales. Although all three methods were feasible, the STT was easier to perform in clinical settings. Type I and Grade 1 were the most commonly observed (64.17% and 61.7%, respectively) regardless of collection method. There was no significant difference between the STT median values and the TFT classifications. The TFT is appropriate for dogs and can be performed using the three suggested sampling methods, with a higher frequency of Type I and Grade 1. Thus, it is possible to use both grading scales in the classification of tear ferning in dogs. © 2017 American College of Veterinary Ophthalmologists.

  5. Tear clearance implications for ocular surface health.

    Science.gov (United States)

    de Paiva, Cintia Sade; Pflugfelder, Stephen C

    2004-03-01

    Tear clearance/turnover provides a global assessment of the function of the lacrimal functional unit and of tear exchange on the ocular surface. It is an indirect measure of dry eye induced inflammation on the ocular surface. It shows better correlation with the severity of ocular irritation symptoms and corneal epithelial disease in dry eye than the Schirmer 1 test. Delayed tear clearance may prove to be the best measure for identifying patients with tear film disorders who may respond to anti-inflammatory therapy.

  6. A Similitude Theory for Bucket Foundations Under Monotonic Horizontal Load in Dense Sand

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo

    2013-01-01

    This paper aims at finding force-displacement relationships to be employed in the design of bucket foundations for offshore wind turbine. This is accomplished by combining small-scale tests and element tests within a theoretical framework. A similitude theory, regarding the lateral displacement o...

  7. Antioxidant content and ultraviolet absorption characteristics of human tears.

    Science.gov (United States)

    Choy, Camus Kar Man; Cho, Pauline; Benzie, Iris F F

    2011-04-01

    Dry eye syndrome is a common age-related disorder, and decreased antioxidant/ultraviolet (UV) radiation protection in tears may be part of the cause. This study aimed to compare the tear antioxidant content and flow rate in young and older adults. The total antioxidant content and UV absorbing properties of various commercially available ophthalmic solutions used to alleviate dry eye symptoms were also examined. Minimally stimulated tears were collected from 120 healthy Chinese adults with no ocular pathology. Two age groups were studied: 19 to 29 years (n = 58) and 50 to 75 years (n = 62). Tear samples from each subject and 13 ophthalmic solutions were analyzed for total antioxidant content (as the Ferric Reducing/Antioxidant Power value). Tear flow rates were estimated from time taken to collect a fixed volume of tear fluid. UV absorbance spectra of pooled fresh reflex tear fluid and the ophthalmic solutions were determined. Results showed that the antioxidant content of minimally stimulated tears from older subjects (398 ± 160 μmol/l) was not significantly lower than that of younger subjects (348 ± 159 μmol/l; p = 0.0915). However, there was a significant difference in the tear flow rates between the two groups (p tears. The effect of low flow rate on the dynamic antioxidant supply to the corneal surface indicates that older subjects have poorer overall defense against photooxidative and other oxidative processes. This could predispose older persons to corneal stress and development of dry eye syndrome. The commercially available artificial tears tested lack both the antioxidant content and UV absorbing characteristics of natural tears. Artificial tears formulations that help restore natural antioxidant and UV absorbing properties to the tear film of the aging eye may help prevent or improve dry eye symptoms and promote ocular health.

  8. A study of re-tear cases after ARCR

    International Nuclear Information System (INIS)

    Ishida, Yasuyuki; Chosa, Etsuo; Yano, Hiroaki

    2011-01-01

    Recently, good clinical outcomes of arthroscopic rotator cuff repair (ARCR) are reported, but the re-tear rate of massive and large rotator cuff tears is still high. The purpose of this study is to review the clinical outcome and postoperative cuff integrity of ARCR in our hospital. We evaluated 80 shoulders (61 males, 19 females), whose age rauged from 30 to 78 (average: 61.8 years old). The size of tears were 8 small, 22 medium, 36 large, and 14 massive. We evaluated the pre-and postoperative Japanese Orthopedic Association (JOA) scored, and MRI findings 12 months postoperatively. We evaluated the cuff integrity and fatty degeneration of the ruptured cuff by Goutallier's classification. Postoperative MRI findings showed complete repair in 56 shoulders (70%) and re-tear in 24 shoulders (30%). Postoperative JOA score was poor in cases with large re-tears. Retear rates were high in large and massive tears, tears with advanced fatty degeneration, and subscapularis tears. As this operation is not a replacement procedure, the quality of the ruptured rotator cuff is important. Further discussion on the operative indication and method is necessary. (author)

  9. Changes of tear film after trabeculectomy in glaucoma

    Directory of Open Access Journals (Sweden)

    Xue-Jun Li

    2015-07-01

    Full Text Available AIM: To learn the changes of the tear film before and after the trabeculectomy of glaucoma and explore the incidence of dry eye and the prevention and control measures.METHODS: The 36 patients(60 eyesof glaucoma were examined in detail before 3d of trabeculectomy and after the surgery at 3, 7, 14 and 30d. The examinations include lower eyelid central river of tears, break-up time(BUT, Schirmer Ⅰ test(SⅠtand staining scores of corneal fluorescein under slit lamp microscope.RESULTS:The tear meniscus height of central lower eyelid was increased and the tear film BUT was shortened at the same time, the scores of SⅠt was reduced and corneal fluorescein staining score was increased at postoperative 3 and 7d compared with that of preoperation. The tear meniscus height of central lower eyelid, tear film BUT and SIt and score of corneal fluorescein staining began to recover in most of the affected eyes after surgery 14d. At 30d after surgery, 22% of patients tear film failed to recover to the preoperative level; dry eye occured in 18% preoperative eyes with normal tear film.CONCLUSION:Trabeculectomy of glaucoma may affect the stability of the tear film and some patients showeing obvious dry eye and should be intervened and treatmented timely.

  10. Impact of environmental adaptation on tear film assessments.

    Science.gov (United States)

    Fagehi, R

    2018-03-01

    The purpose of this study was to investigate the effect of ocular environmental adaptation on clinical tear film assessment. Thirty subjects (male, mean age 23±2.5) participated in this study. A number of clinical tear film tests were applied, including: fluorescein tear break-up time (FTBUT), Schirmer test and tear prism height test (TPH). The tear physiology of each subject was evaluated twice, once immediately when they arrived from the external environment, and then after 30minutes adaptation in the exam room environment. The mean values were: Schirmer test A (22.1±2.99), Schirmer test B (24.2±2.63), FTBUT A (8.00±1.94), FTBUT B (9.13±2.04), TPH A (0.179±0.026) and TPH B* (0.187±0.023). Statistical testing using Wilcoxon-signed rank test showed a significant difference between the Schirmer test results measured at the different times (P=0.008). Also, the FTBUT and tear prism height test results showed significant differences between the two evaluation times, (P=0.001, 0.011, respectively) (A: tear assessed when the subject comes from the outside environment, B: tear film assessed after 30min adaptation in the clinical environment). This study showed a significant difference between the tear film test results evaluated when the subjects were assessed immediately from the outside environment and after an adaptation time in the clinic environment. Practitioners must consider the effect of differences between external and clinical environment adaptation on clinical tear film physiology. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  11. A comparison of accuracy of clinical tests and MRI in the diagnosis ...

    African Journals Online (AJOL)

    Objective: To compare the accuracy of clinical examination versus Magnetic Resonance Imaging (MRI) in the diagnoses of meniscal and Anterior Cruciate Ligament (ACL) tears after trauma. Methods: Between January 2011 and December 2015, 147 consecutive patients with previous history of knee injury were seen and ...

  12. Prototype bucket foundation for wind turbines

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten

    The first full scale prototype bucket foundation for wind turbines has been installed in October 2002 at Aalborg University offshore test facility in Frederikshavn, Denmark. The suction caisson and the wind turbine have been equipped with an online monitoring system, consisting of 15 accelerometers...... and a real-time data-acquisition system. The report concerns the in service performance of the wind turbine, with focus on estimation of the natural frequencies of the structure/foundation. The natural frequencies are initially estimated by means of experimental Output-only Modal analysis. The experimental...... estimates are then compared with numerical simulations of the suction caisson foundation and the wind turbine. The numerical model consists of a finite element section for the wind turbine tower and nacelle. The soil-structure interaction of the soil-foundation section is modelled by lumped-parameter models...

  13. Wave Forces on Transition Pieces for Bucket Foundations for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Nezhentseva, Anastasia; Andersen, Thomas Lykke; Andersen, Lars Vabbersgaard

    to a bucket foundation (suction caisson) located at 35 m water depth in the North Sea. Several models of the TPs (wedge-shaped steel flange-reinforced shear panels, conical and doubly curved with or without cutaways) are tested in a wave flume and compared with respect to wave loading. Due to a larger size...

  14. MR imaging before arthroscopy in knee joint disorders?

    International Nuclear Information System (INIS)

    Rappeport, E.D.; Mehta, S.; Wieslander, S.B.; Schwarz Lausten, G.; Thomsen, H.S.

    1996-01-01

    Purpose: To review the current literature examining the relative merits of arthroscopy and MR imaging of the knee. Material and Methods: All papers comparing MR imaging with arthroscopy published within the last 10 years according to Medline were collected and read. Results: Technology has improved considerably during recent years allowing detailed non-invasive visualization of the knee. In particular, the development of cheaper whole-body and dedicated low-field MR units has opened up for non-invasive inspection of the knee at reasonable cost. Meniscal tears can be detected with accuracy rates of around 90% and rupture of the anterior cruciate ligament with accuracy rates of around 93% compared to arthroscopy. However, arthroscopy is not the ideal gold standard, since it has weak points, e.g. peripheral meniscal tears or osteochondritis without apparent damage to the cartilage. Conclusion: Based on the overwhelming literature it seems safe to conclude that MR examinations of the knee should be performed before arthroscopy is undertaken. (orig.)

  15. Meniscus repair and regeneration: review on current methods and research potential

    Directory of Open Access Journals (Sweden)

    C Scotti

    2013-01-01

    Full Text Available Meniscus regeneration is an unsolved clinical challenge. Despite the wide acceptance of the degenerative consequences of meniscectomy, no surgical procedure has succeeded to date in regenerating a functional and long-lasting meniscal fibrocartilage. Research proposed a number of experimental approaches encompassing all the typical strategies of regenerative medicine: cell-free scaffolds, gene therapy, intra-articular delivery of progenitor cells, biological glues for enhanced bonding of reparable tears, partial and total tissue engineered meniscus replacement. None of these approaches has been completely successful and can be considered suitable for all patients, as meniscal tears require specific and patient-related treatments depending on the size and type of lesion. Recent advances in cell biology, biomaterial science and bioengineering (e.g., bioreactors have now the potential to drive meniscus regeneration into a series of clinically relevant strategies. In this tutorial paper, the clinical need for meniscus regeneration strategies will be explained, and past and current experimental studies on meniscus regeneration will be reported.

  16. Influence of preoperative artificial tears on tear film after phacoemulsification on dry eye of diabetes patients

    Directory of Open Access Journals (Sweden)

    Rui Su

    2015-05-01

    Full Text Available AIM: To discuss the artificial tears on the tear film of diabetic patients with dry eye preoperatively, and the influence on the tear film's fuctional after phacoemulsification.METHODS: Fifty-four diabetic patients with dry eye(60 eyeswere followed up before phacoemulsification. Preoperatively, group A(30 eyes in 28 caseswas treated with Hydroxyl Indican eye drops and group B(30 eyes in 26 caseswas not treated. Postoperatively, both group A and B were treated with Tobramycin Dexamethasone eye drops, Oprah Winfrey Ibuprofen eye drops and Hydroxyl Indican eye drops. Dry eye symptoms, break up time(BUT, Schirmer Ⅰ test(S Ⅰ t, fluorescein stain test(FIwere measured at 3d preoperatively, and 1, 7, 30, 90d postoperatively.RESULTS: At 3d preoperatively, there was no statistical differences between the two groups for dry eye symptoms, BUT, SⅠt, FI(P>0.05. At 1 and 7d postoperatively, there were significant statistical differents between the two groups for dry eye symptoms(PPP>0.05.CONCLUSION: Using artificial tears before phacoemulsification can improve symptoms of the diabetic patients with dry eye and accelerate the recovery of the tear film.

  17. Buckling of Monopod Bucket Foundations – Influence of Boundary Conditions and Soil-structure Interaction

    DEFF Research Database (Denmark)

    Madsen, Søren; Pinna, Rodney; Randolph, M. F.

    2015-01-01

    of large-diameter bucket foundations. Since shell structures are generally sensitive to initially imperfect geometries, eigenmode-affine imperfections are introduced in a nonlinear finite-element analysis. The influence of modelling the real lid structure compared to classic boundary conditions...

  18. MR imaging of rotator cuff tears

    International Nuclear Information System (INIS)

    Kumagai, Hideo

    1992-01-01

    A total of 115 patients with clinical symptoms and signs suggesting rotator cuff tears underwent MR imaging with a 1.5-Tesla system. The body coil was used as the receiver coil in 24 patients and a single 10 cm surface coil in 91. Arthrography or MR imaging with intra-articular Gd-DTPA (MR arthrography) was performed in 95 of the 115. T2-weighted images with the body coil showed high signal intensity lesions in rotator cuffs in only seven of the 10 patients who had tears demonstrated by arthrography or MR arthrography. On the other hand, T2-weighted images with the surface coil demonstrated high signal intensity lesions in cuffs in all 27 patients who were diagnosed to have tears by arthrography or MR arthrography. In 12 patietns, T2-wighted images with the surface coil showed high signal intensity lesions in cuffs, while arthrography and MR arthrography did not show tears. Surgery was performed in four of the 12 patients and partial tears were confirmed. A single 10 cm surface coil, 3 mm slice thickness and 2.5 second repetition time seem to account for the fine visualization of cuff tears by the T2-weighted images. These results suggest that T2-weighted images obtained with the surface coil are superior to arthrography and MR arthrography. (author)

  19. Influence of Ophthalmic Solutions on Tear Components.

    Science.gov (United States)

    Shigeyasu, Chika; Yamada, Masakazu; Akune, Yoko

    2016-11-01

    Tear fluids are a mixture of secretions derived from lacrimal glands, accessory lacrimal glands, conjunctiva, and meibomian glands. Compositional changes to tears occur in the normal state and during ocular surface disease, such as dry eye conditions. We have investigated compositional changes to tears after topical application of ophthalmic solutions, with regard to tear-specific proteins (secretory immunoglobulin A, lactoferrin, lipocalin-1, and lysozyme) and ocular surface mucin in normal and dry eye conditions using high-performance liquid chromatography. After application of saline solution (0.9% sodium chloride) in normal subjects, transient but significant decreases in all tear components were observed. The recovery of protein concentrations took up to 30 minutes and lasted longer when the saline solution was applied more frequently. When applying ophthalmic solutions, a balance between washout and dilutional effects should be considered in addition to the therapeutic effect. Investigation of the effect of diquafosol solution (3%) in normal subjects revealed a significant increase in sialic acid concentration, a marker of ocular mucin, at 5 minutes after application, whereas a significant decrease was observed with saline. This result indicates the accelerated secretion of mucin from ocular tissues induced by diquafosol. A clinical study to determine the efficacy of diquafosol in patients with dry eye revealed improvements in tear breakup time, keratoconjunctival staining scores, and Schirmer test score, accompanied by an increase in sialic acid concentration in tears. Investigating normal and dry eye conditions through tear analysis may clarify the pathophysiology of dry eye conditions and support the efficacy of treatments.

  20. Efficacy of artificial tears for children xerophthalmia

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2016-03-01

    Full Text Available AIM:To observe the efficacy and safety of artificial tears for children xerophthalmia.METHODS:Fifty-eight cases with 116 eyes were diagnosed as xerophthalmia by tear break-up time(BUT, Schirmer Ⅰ test(SⅠt, tear meniscus height, corneal staining, meibomian gland function test and were given artificial tears therapy for 1mo. Then the aforementioned tests were conducted again for statistical analysis.RESULTS:The mean BUT of all the children before treatments was 6.03±1.19s, SⅠt was 7.67±2.32mm/5min, tear meniscus height was 0.20±0.02mm, corneal staining was 1.02±0.13 scores and meibomian gland function was 2.45±0.86 scores. Sixty-two eyes in 31 cases were the lipid-deficient type, 40 eyes in 20 cases were aqueous-deficient type, and 14 eyes in 7 cases were other types. According to their types, corresponding artificial tears therapy was given. At 1mo after treatments, the clinical symptoms were improved significantly. BUT was 13.72±1.83s, SⅠt was 12.38±3.64mm/5min, tear meniscus height was 0.36±0.08mm, corneal fluorescein staining was 0.03±0.24 scores and meibomian gland function was 1.57±0.93 scores. Compared with those before treatments, the difference of each observed indicators was statistically significant(PCONCLUSION:Artificial tears treatment for children xerophthalmia is safe and effective.

  1. Radiologic findings of double contrast knee arthrography

    International Nuclear Information System (INIS)

    Choi, Hye Ran; Ahn, Byeong Yeob; Kim, Mi Young; Lee, So Hyun; Suh, Chang Hae; Chung, Won Kyun

    1990-01-01

    The double contrast arthrography of the knee is a highly accurate diagnostic modality in wide rage of the clinical disorders of the knee. It allows radiological assessment of the menisci, the articular cartilages, the synovium and the ligaments. The double contrast knee arthrography was performed in 356 cases at Inha hospital for about 3 years from June 1986 to June 1989. Among them, 115 cases were abnormal, and were analyzed clinically and radiologically with the back ground of the operative finding. The results were as follows ; 1. Of the 115 cases, male were 77 and female 38. Male exceeds female in the ratio of 2 : 1. 2. The age group of 20 - 39 years was commonly involved (60%). 3. The right knee was more commonly involved than the left and the medial meniscus tear was more common (61%). The posterior horn of the meniscus was more frequently torn than the other parts of the meniscus (42%). 4. The incidence of the bucket-handle tear was the most frequent (33%). 5. The cases of the popliteal cyst were 16 (13.9%), and the combined meniscus tears were in 4 cases (25%). 6. The numbers of the discoid meniscus were 9 (7.8%), and all were present in the lateral meniscus, and combined tears were in 4 cases (44.4%). 7. The diagnostic accuracy of the double contrast knee arthrogram was 82.7% compared with operative finding. The false positive examination were 17.3%

  2. Prisen Årets studenter start-up går til Drop Bucket

    DEFF Research Database (Denmark)

    Lassen, Lisbeth

    2015-01-01

    DTU’s ny pris for årets mest innovative studerende blev ved universitetets årsfest givet til Heiða Gunnarsdóttir Nolsøe og Marie Stampe Berggreen, som står bag virksomheden Drop Bucket. Koncerndirektør for innovation og entreprenørskab, Marianne Thellersen, overakte prisen til de to innovatører s...

  3. Long-Term MRI Findings in Operated Rotator Cuff Tear

    International Nuclear Information System (INIS)

    Kyroelae, K.; Niemitukia, L.; Jaroma, H.; Vaeaetaeinen, U.

    2004-01-01

    Purpose: To describe magnetic resonance imaging (MRI) findings at long-term follow-up after rotator cuff (RC) tear using standard MRI sequences without fat saturation. Material and Methods: Twenty-eight patients aged 55.8±7.6 underwent MRI examination 4.6±2.1 years after surgery for RC tear. Standard sequences in oblique coronal, oblique sagittal, and axial planes were obtained. The RC, including re-tears and tendon degeneration, was independently evaluated by two observers. Thickness of the supraspinatus tendon and narrowing of the subacromial space were measured. The clinical outcome was evaluated with the Constant score and compared with the MRI findings. Results: The RC tear was traumatic in 18 (64%) patients and degenerative in 10 (36%). At follow-up, 11 (39%) had normal RC tendons with good clinical outcome. Four (14%) patients had painful tendinosis without RC tear. A full-thickness RC tear was found in 7 (25%) patients and a partial tear in 6 (21%). In one patient with a full-thickness tear, and in two with partial tear, tendinosis was found in another of the RC tendons. The subacromial space was narrowed in 13 (46%) of the patients. A narrowing of the subacromial space correlated with re-tear (P<0.05). Conclusions: The RC may be evaluated with standard MRI sequences without fat saturation at long-term follow-up. A normal appearance of the RC is correlated with good clinical outcome, while re-tear and tendinosis are associated with pain

  4. The tale of two buckets and associated containers: impact on aedes albopictus oviposition

    Science.gov (United States)

    Aedes albopictus is an invasive species. Its oviposition behavior is the subject of several projects in our research unit. The main emphasis of this presentation is a study which utilizes two five gallon buckets, one heated and one with ambient temperature. The heat is provided by an aquarium hea...

  5. Epidemiology, natural history, and indications for treatment of rotator cuff tears.

    Science.gov (United States)

    Tashjian, Robert Z

    2012-10-01

    The etiology of rotator cuff disease is likely multifactorial, including age-related degeneration and microtrauma and macrotrauma. The incidence of rotator cuff tears increases with aging with more than half of individuals in their 80s having a rotator cuff tear. Smoking, hypercholesterolemia, and genetics have all been shown to influence the development of rotator cuff tearing. Substantial full-thickness rotator cuff tears, in general, progress and enlarge with time. Pain, or worsening pain, usually signals tear progression in both asymptomatic and symptomatic tears and should warrant further investigation if the tear is treated conservatively. Larger (>1-1.5 cm) symptomatic full-thickness cuff tears have a high rate of tear progression and, therefore, should be considered for earlier surgical repair in younger patients if the tear is reparable and there is limited muscle degeneration to avoid irreversible changes to the cuff, including tear enlargement and degenerative muscle changes. Smaller symptomatic full-thickness tears have been shown to have a slower rate of progression, similar to partial-thickness tears, and can be considered for initial nonoperative treatment due to the limited risk for rapid tear progression. In both small full-thickness tears and partial-thickness tears, increasing pain should alert physicians to obtain further imaging as it can signal tear progression. Natural history data, along with information on factors affecting healing after rotator cuff repair, can help guide surgeons in making appropriate decisions regarding the treatment of rotator cuff tears. The management of rotator cuff tears should be considered in the context of the risks and benefits of operative versus nonoperative treatment. Tear size and acuity, the presence of irreparable changes to the rotator cuff or glenohumeral joint, and patient age should all be considered in making this decision. Initial nonoperative care can be safely undertaken in older patients (>70

  6. A prospective evaluation of survivorship of asymptomatic degenerative rotator cuff tears.

    Science.gov (United States)

    Keener, Jay D; Galatz, Leesa M; Teefey, Sharlene A; Middleton, William D; Steger-May, Karen; Stobbs-Cucchi, Georgia; Patton, Rebecca; Yamaguchi, Ken

    2015-01-21

    The purpose of this prospective study was to report the long-term risks of rotator cuff tear enlargement and symptom progression associated with degenerative asymptomatic tears. Subjects with an asymptomatic rotator cuff tear in one shoulder and pain due to rotator cuff disease in the contralateral shoulder enrolled as part of a prospective longitudinal study. Two hundred and twenty-four subjects (118 initial full-thickness tears, fifty-six initial partial-thickness tears, and fifty controls) were followed for a median of 5.1 years. Validated functional shoulder scores were calculated (visual analog pain scale, American Shoulder and Elbow Surgeons [ASES], and simple shoulder test [SST] scores). Subjects were followed annually with shoulder ultrasonography and clinical evaluations. Tear enlargement was seen in 49% of the shoulders, and the median time to enlargement was 2.8 years. The occurrence of tear-enlargement events was influenced by the severity of the final tear type, with enlargement of 61% of the full-thickness tears, 44% of the partial-thickness tears, and 14% of the controls (p tear enlargement. One hundred subjects (46%) developed new pain. The final tear type was associated with a greater risk of pain development, with the new pain developing in 28% of the controls, 46% of the shoulders with a partial-thickness tear, and 50% of those with a full-thickness tear (p tear enlargement was associated with the onset of new pain (p muscle were associated with tear enlargement, with supraspinatus muscle degeneration increasing in 4% of the shoulders with a stable tear compared with 30% of the shoulders with tear enlargement (p tear showed increased infraspinatus muscle degeneration compared with 28% of those in which the tear had enlarged (p = 0.07). This study demonstrates the progressive nature of degenerative rotator cuff disease. The risk of tear enlargement and progression of muscle degeneration is greater for shoulders with a full-thickness tear, and tear

  7. Comparison of gait and pathology outcomes of three meniscal procedures for induction of knee osteoarthritis in sheep.

    Science.gov (United States)

    Cake, M A; Read, R A; Corfield, G; Daniel, A; Burkhardt, D; Smith, M M; Little, C B

    2013-01-01

    Meniscectomy (MX) of sheep induces a well-established animal model of human osteoarthritis (OA). This study compared the clinical (lameness) and pathological outcomes of unilateral, complete medial MX vs two less traumatic and more easily performed meniscal destabilisation procedures. Four-year old wethers (n = 6/group) underwent sham operation, cranial pole release (CPR), mid-body transection (MBT) or total MX of the medial meniscus. Joints were assessed for gross pathology (cartilage erosion and osteophytes), histomorphometry, two histopathology scoring methods (modified Mankin-type and Pritzker score), and immunohistology for ADAMTS- and MMP-cleaved neoepitopes, at 12 weeks post-op. Ground reaction forces (GRFs) were determined by force plate in a subset (n = 4/group) at baseline, 2.5, 8, and 12 weeks post-op. Gross pathology scores of operated groups differed significantly from sham animals (P osteophyte formation. Similarly, histopathology scores were significantly elevated vs sham but did not differ between operated groups at P subchondral sclerosis, suggesting some residual biomechanical effect from the destabilised but intact meniscus. Few significant differences were noted between operated groups in force plate analyses, though gait abnormalities appeared to be least in CPR sheep, and most persistent (>12 weeks) in MBT animals. The well-validated ovine MX model and the simpler meniscal destabilisation procedures resulted in broadly similar joint pathology and lameness. Meniscal CPR or MBT, as easier and more clinically relevant procedures, may represent preferred models for the induction of OA and evaluation of potential disease-modifying therapies. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  8. Kinetic theory of tearing instabilities

    International Nuclear Information System (INIS)

    Drake, J.F.; Lee, Y.C.

    1977-01-01

    The transition of the tearing instability from the collisional to the collisionless regime is investigated kinetically using a Fokker--Planck collision operator to represent electron-ion collisions. As a function of the collisionality of the plasma, the tearing instability falls into three regions, which are referred to as collisionless, semi-collisional, and collisional. The width Δ of the singular layer around kxB 0 =0 is limited by electron thermal motion along B 0 in the collisional and semi-collisional regimes and is typically smaller than rho/sub i/, the ion Larmor radius. Previously accepted theories, which are based on the assumption Δvery-much-greater-thanrho/sub i/, are found to be valid only in the collisional regime. The effects of density and temperature gradients on the instabilities are also studied. The tearing instability is only driven by the temperature gradient in the collisional and semi-collisional regimes. Numerical calculations indicate that the semi-collisional tearing instability is particularly relevant to present day high temperature tokamak discharges

  9. Long-Term Data Reveal Rate and Risk Factors for Subsequent Surgeries Following Initial ACL Reconstruction

    Science.gov (United States)

    ... Rupture of the knee’s ACL is a common sports-related injury. It is associated with other knee problems, such as meniscal tears and knee instability. ... after anterior cruciate ligament reconstruction. Am J of Sports Med. 2013; ... treatment and prevention of arthritis and musculoskeletal and skin diseases; the ...

  10. Radiation-induced femoral head necrosis

    African Journals Online (AJOL)

    2011-03-25

    Mar 25, 2011 ... had open medial menisectomy of the left knee following medial meniscal tear ... postoperative recovery and mobilised full weight-bearing immediately [Figure 6]. ... obtained from the oncologists at the time of this review), and there was a ... previous trauma such as femoral neck fracture, Gaucher's disease ...

  11. Human tears reveal insights into corneal neovascularization.

    Science.gov (United States)

    Zakaria, Nadia; Van Grasdorff, Sigi; Wouters, Kristien; Rozema, Jos; Koppen, Carina; Lion, Eva; Cools, Nathalie; Berneman, Zwi; Tassignon, Marie-José

    2012-01-01

    Corneal neovascularization results from the encroachment of blood vessels from the surrounding conjunctiva onto the normally avascular cornea. The aim of this study is to identify factors in human tears that are involved in development and/or maintenance of corneal neovascularization in humans. This could allow development of diagnostic tools for monitoring corneal neovascularization and combination monoclonal antibody therapies for its treatment. In an observational case-control study we enrolled a total of 12 patients with corneal neovascularization and 10 healthy volunteers. Basal tears along with reflex tears from the inferior fornix, superior fornix and using a corneal bath were collected along with blood serum samples. From all patients, ocular surface photographs were taken. Concentrations of the pro-angiogenic cytokines interleukin (IL)-6, IL-8, Vascular Endothelial Growth Factor (VEGF), Monocyte Chemoattractant Protein 1 (MCP-1) and Fas Ligand (FasL) were determined in blood and tear samples using a flow cytometric multiplex assay. Our results show that the concentration of pro-angiogenic cytokines in human tears are significantly higher compared to their concentrations in serum, with highest levels found in basal tears. Interestingly, we could detect a significantly higher concentration of IL- 6, IL-8 and VEGF in localized corneal tears of patients with neovascularized corneas when compared to the control group. This is the first study of its kind demonstrating a significant difference of defined factors in tears from patients with neovascularized corneas as compared to healthy controls. These results provide the basis for future research using animal models to further substantiate the role of these cytokines in the establishment and maintenance of corneal neovascularization.

  12. Buckling of Bucket Foundations During Installation

    DEFF Research Database (Denmark)

    Madsen, Søren

    There is a great politically will to expand the green energy market in these times. A proven green technology is wind turbines. Wind turbines have been installed in great numbers on land over the last decades. However, the current development in wind turbine design leads to larger turbine sizes...... in order to reduce the cost of energy. This limits the on land application due to transportation limitations and unwillingness from prospect neighbours. Thus, offshore wind energy started developing over the last couple of years. Although installing the wind turbines offshore resolves the before men tioned...... issues, it brings up the cost of energy mainly due to increased installation and maintenance costs. A very large part—up to 30–50% using current technology—of the installation cost origins from the expenses related to the installation of foundations. A new foundation concept—the bucket foundation...

  13. From Newton's bucket to rotating polygons

    DEFF Research Database (Denmark)

    Bach, B.; Linnartz, E. C.; Vested, Malene Louise Hovgaard

    2014-01-01

    We present an experimental study of 'polygons' forming on the free surface of a swirling water flow in a partially filled cylindrical container. In our set-up, we rotate the bottom plate and the cylinder wall with separate motors. We thereby vary rotation rate and shear strength independently...... and move from a rigidly rotating 'Newton's bucket' flow to one where bottom and cylinder wall are rotating oppositely and the surface is strongly turbulent but flat on average. Between those two extremes, we find polygonal states for which the rotational symmetry is spontaneously broken. We investigate...... the phase diagram spanned by the two rotational frequencies at a given water filling height and find polygons in a regime, where the two frequencies are sufficiently different and, predominantly, when they have opposite signs. In addition to the extension of the family of polygons found with the stationary...

  14. The natural course of nonoperatively treated rotator cuff tears: an 8.8-year follow-up of tear anatomy and clinical outcome in 49 patients.

    Science.gov (United States)

    Moosmayer, Stefan; Gärtner, Anne V; Tariq, Rana

    2017-04-01

    The natural course of nonoperatively treated rotator cuff tears is not fully understood. We explored the long-term development of tear anatomy and assessed functional outcomes. Eighty-nine small to medium-sized full-thickness tears of the rotator cuff, all primarily treated by physiotherapy, were identified retrospectively. Twenty-three tears needed surgical treatment later on, and 17 patients were unable to meet for follow-up. The remaining 49 still unrepaired tears were re-examined after 8.8 (8.2-11.0) years with sonography. Re-examination by magnetic resonance imaging was possible for 37 patients. Shoulder function was assessed with shoulder scores. Primary outcome measures were progression of tear size, muscle atrophy, and fatty degeneration and the Constant score (CS). Mean tear size increased by 8.3 mm in the anterior-posterior plane (P = .001) and by 4.5 mm in the medial-lateral plane (P = .001). Increase of tear size was -5 to +9.9 mm in 33 patients, 10 to 19.9 mm in 8 patients, and ≥20 mm in 8 patients. The CS was 81 points for tear increases Muscle atrophy and fatty degeneration progressed in 18 and 15 of the 37 patients, respectively. In tears with no progression of atrophy, the CS was 82 points compared with 75.5 points in tears with progression (P = .04). Anatomic tear deterioration was found in the majority of patients, but it was often moderate. Large tear size increases and progression of muscle atrophy were correlated to a poorer functional outcome. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  15. Age-related changes in the signal value of tears.

    Science.gov (United States)

    Zeifman, Debra M; Brown, Sarah A

    2011-08-12

    Emotional tears may be uniquely human and are an effective signal of distress in adults. The present study explored whether tears signal distress in younger criers and whether the effect of tears on observers is similar in magnitude across the life span. Participants rated photographs of crying infants, young children, and adults, with tears digitally removed or added. The effectiveness of tears in conveying sadness and eliciting sympathy was greatest for images of adults, intermediate for images of children, and least potent for images of infants. These findings suggest that the signal value of tears varies with the age of the crier. The results may shed light on the functional significance of crying at different stages of human development.

  16. Time course of changes in tear meniscus radius and blink rate after instillation of artificial tears.

    Science.gov (United States)

    Bandlitz, Stefan; Purslow, Christine; Murphy, Paul J; Pult, Heiko

    2014-08-26

    Using a novel digital meniscometer (PDM), alterations in tear meniscus radius (TMR) were measured simultaneously with blink rate (BR) following the instillation of artificial tears. Central TMR and BR of 22 subjects (11 male and 11 female; mean age, 24.3 ± 2.6 SD years) were measured at baseline, and 0, 1, 5, 10, and 30 minutes after instillation of an artificial tear containing hydroxypropyl-guar and glycol (SYS) or saline (SAL). A dose of 35 μL was applied in one eye in a randomized order with a washout period between each drop. For SAL, compared to baseline TMR (0.33 ± 0.08 mm), TMR significantly increased with drop instillation (1.55 ± 0.69 mm) and at 1 minute (0.66 ± 0.36 mm; P tears. Difference in residence time reflects the different viscosity of each drop. An overload with a large drop may result in an initially increased BR. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  17. MR Imaging of Rotator Cuff Tears: Correlation with Arthroscopy

    Science.gov (United States)

    Bhandary, Sudarshan; Khandige, Ganesh; Kabra, Utkarsh

    2017-01-01

    Introduction Rotator cuff tears are quite common and can cause significant disability. Magnetic Resonance Imaging (MRI) has now emerged as the modality of choice in the preoperative evaluation of patients with rotator cuff injuries, in view of its improved inherent soft tissue contrast and resolution. Aim To evaluate the diagnostic accuracy of routine MRI in the detection and characterisation of rotator cuff tears, by correlating the findings with arthroscopy. Materials and Methods This prospective study was carried out between July 2014 and August 2016 at the AJ Institute of Medical Sciences, Mangalore, Karnataka, India. A total of 82 patients were diagnosed with rotator cuff injury on MRI during this period, out of which 45 patients who underwent further evaluation with arthroscopy were included in this study. The data collected was analysed for significant correlation between MRI diagnosis and arthroscopic findings using kappa statistics. The sensitivity, specificity, predictive value and accuracy of MRI for the diagnosis of full and partial thickness tears were calculated using arthroscopic findings as the reference standard. Results There were 27 males and 18 females in this study. The youngest patient was 22 years and the oldest was 74 years. Majority of rotator cuff tears (78%) were seen in patients above the age of 40 years. MRI showed a sensitivity of 89.6%, specificity of 100%, positive predictive value of 100% and negative predictive value of 83.3% for the diagnosis of full thickness rotator cuff tears. For partial thickness tears, MRI showed a sensitivity of 100%, specificity of 86.6%, positive predictive value of 78.9% and negative predictive value of 100%. The accuracy was 93.1% for full thickness tears and 91.1% for partial thickness tears. The p-value was less than 0.01 for both full and partial thickness tears. There was good agreement between the MRI and arthroscopic findings, with kappa value of 0.85 for full thickness tears and 0.81 for partial

  18. Meniscal root entrapment of an osteochondritis dissecans loose body.

    Science.gov (United States)

    Jones, Christopher R; McMonagle, Joseph S; Garrett, William E

    2014-09-01

    Loose bodies are relatively common in the knee. On radiographs they can often be seen in the medial and lateral gutters, intercondylar notch, and the posterior compartment. At times an apparent loose body is not free to move in the knee because it has been covered by synovium and is no longer mobile. It is uncommon for an osteochondral loose body to become incorporated into meniscal tissue. We report a case of an apparent loose body becoming incorporated into the posterior horn and root of the medial meniscus. We are not aware that this condition has been previously reported. Because removing the entire loose body would have destabilized the posterior root of the medial meniscus, it is important to be aware of this potential occurrence.

  19. SLAP tears of the glenoid labrum in contact athletes.

    Science.gov (United States)

    Funk, Lennard; Snow, Martyn

    2007-01-01

    To describe the distribution and clinical presentation of labral injuries in rugby players and the time taken for them to return to sports. Retrospective cohort study. Busy shoulder practice in the North West of England, treating a large number of professional athletes. A review of 51 shoulder arthroscopies performed on professional rugby players over a 35 month period. All patients diagnosed with a SLAP lesion at arthroscopy were identified. Eighteen patients had a documented SLAP tear; this group represented our study population. Arthroscopic debridement and/or stabilization was carried out for all labral injuries using Panaloc anchors and No. 2 PDS via a 2 portal technique. Classification of injury, Satisfaction, Time to return to play. The incidence of SLAP tears in our study population was 35%. There were 11 isolated SLAP tears (61%), 3 SLAP tears associated with a Bankart lesion (17%), 2 SLAP tears associated with a posterior labral lesion (11%), and 2 SLAP tears associated with an anterior and posterior labral injuries (11%). Of the 18 SLAP tears, 14 (78%) were type 2, 3 (17%) were type 3, and 1 (5%) was type 4. None of the patients with a SLAP tear presented with symptoms of instability. MR Arthrogram had a 76% sensitivity for detecting SLAP tears. By 6 months postsurgery, 89% of patients were satisfied. Patients with isolated SLAP tears were the quickest to return to sports, at an average of 2.6 months postsurgery. SLAP tears are a common injury in rugby players. These can often be diagnosed with MR arthrography. Arthroscopic repair is associated with excellent results and early return to sports.

  20. Advanced Rotator Cuff Tear Score (ARoCuS): a multi-scaled tool for the classification and description of rotator cuff tears.

    Science.gov (United States)

    Walter, S G; Stadler, T; Thomas, T S; Thomas, W

    2018-03-02

    To introduce a (semi-)quantitative surgical score for the classification of rotator cuff tears. A total of 146 consecutive patients underwent rotator cuff repair and were assessed using the previously defined Advanced Rotator Cuff Tear Score (ARoCuS) criteria: muscle tendon, size, tissue quality, pattern as well as mobilization of the tear. The data set was split into a training (125 patients) and a testing set (21 patients). The training data set fitted a nonlinear predictive model of the tear score based on the ARoCuS criteria, while the testing data served as control. Based on the scoring results, rotator cuff tears were assigned to one of four categories (ΔV I-IV) and received a stage-adapted treatment. For statistical analysis, mean values ± standard deviation, interclass correlation coefficients (ICC) and kappa values were calculated. Overall, 32 patients were classified as ΔV I, 68 as ΔV II and 37 as ΔV III. Nine patients showed ΔV IV tears. Patients of all ΔV groups improved significantly their Constant scores (p tears in a standardized and reproducible manner.