WorldWideScience

Sample records for fibrocartilage complex tears

  1. 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.

  2. Arthroscopic assisted tendon reconstruction for triangular fibrocartilage complex irreparable tears.

    Science.gov (United States)

    Luchetti, R; Atzei, A

    2017-05-01

    We report our 11-year experience of performing arthroscopically assisted triangular fibrocartilage complex reconstruction in the treatment of chronic distal radio-ulnar joint instability resulting from irreparable triangular fibrocartilage complex injuries. Eleven patients were treated. Three skin incisions were made in order to create radial and ulna tunnels for passage of the tendon graft, which is used to reconstruct the dorsal and palmar radio-ulnar ligaments, under fluoroscopic and arthroscopic guidance. At a mean follow-up of 68 months all but one had a stable distal radio-ulnar joint. Pain and grip strength, Mayo wrist score, Disability of the Arm Hand and Shoulder and patient-rated wrist and hand evaluation scores improved. The ranges of forearm rotation remained largely unchanged. Complications included an early tendon graft tear, two late-onset graft ruptures, one ulna styloid fracture during surgery and persistent wrist discomfort during forearm rotation requiring tendon graft revision in one case. An arthroscopic assisted approach for triangular fibrocartilage complex reconstruction appears safe and produces comparable results with the open technique. IV.

  3. [Treatment of triangular fibrocartilage complex tear under wrist arthroscopy].

    Science.gov (United States)

    Mi, Kun; Liu, Wu; Liu, Pengfei; Feng, Zhibin; Li, Yuwen; Hui, Guisheng

    2011-01-01

    To evaluate the treatment and effects of wrist arthroscopy in tear of triangular fibrocartilage complex (TFCC). Between January 2006 and December 2008, 16 patients with tear of TFCC were treated. Of 16 patients, 11 were male and 5 were female with an average age of 32.5 years (range, 25-51 years). Injury was caused by sprain in 12 cases, and by falling in 4 cases. The locations were the left side in 10 cases and the right side in 6 cases. The mean injury duration was 3 months to 6 years and 2 months. The main clinical symptoms included wrist powerlessness and ulnar-sided wrist pain which was aggravated with clench fist and lifting heavy things. The results of the ulnar-sided wrist stress test were positive in 14 cases and negative in 2 cases. The preoperative values of wrist range of motion (ROM) were (45.58 +/- 5.18) degrees at volar flexion, (41.22 +/- 3.83) degrees at dorsal extension, (17.82 +/- 2.48) degrees at radial deviation, (21.35 +/- 4.61) degrees at ulnar deviation, (69.85 +/- 8.36) degrees at pronation, and (70.13 +/- 6.34) degrees at supination. According to Palmer standard, 10 cases of IA were treated with debridement; 3 cases of IB with suture and 1 of them failed and was partially excised; 2 cases of IC with debridement on triangular fibrocartilage disc, ulnolunate ligament, and ulnotriguetrum ligament; and 1 case of ID with trimming plastic operation. All incisions healed by first intention, and no complications of joint infection or neurovascular injury was found. All patients were followed up 14-38 months (mean, 18.5 months). Fifteen patients were restored to normal life and work without ulnar-sided wrist pain. One patient had no pain, but he had wrist powerless. The values of ROM at last follow-up were (50.16 +/- 6.21) degrees at volar flexion, (45.37 +/- 4.65) degrees at dorsal extension, (18.95 +/- 3.56) degrees at radial deviation, (26.28 +/- 5.09) degrees at ulnar deviation, (78.87 +/- 7.69) degrees at pronation, and (76.46 +/- 8

  4. A Systematic Review of Outcomes after Arthroscopic Débridement for Triangular Fibrocartilage Complex Tear.

    Science.gov (United States)

    Saito, Taichi; Malay, Sunitha; Chung, Kevin C

    2017-11-01

    Evidence regarding the effectiveness of arthroscopic débridement for a triangular fibrocartilage complex tear is uncertain. The purpose of this study was to conduct a systematic review of outcomes to evaluate the effectiveness of débridement for triangular fibrocartilage complex tears. The authors searched all available literature in the PubMed, Embase, and MEDLINE (Ovid) databases for articles reporting on triangular fibrocartilage complex tear débridement. Data collection included arc of motion, grip strength, patient-reported outcomes, and complications. A total of 1723 unique studies were identified, of which 18 studies met the authors' criteria. The mean before and after arc of wrist extension/flexion motion values were 120 and 146 degrees (six studies). The mean before and after grip strength values were 65 percent and 91 percent of the contralateral side (10 studies). Disabilities of the Arm, Shoulder, and Hand scores (six studies) and pain visual analogue scale scores (seven studies) improved from 39 to 18, and from 7 to 3, respectively. The mean pain visual analogue scale score after débridement was 1.9 in the ulnar-positive group and 2.4 in the ulnar-neutral and ulnar-negative groups. Eighty-seven percent of patients returned to their original work. Patients reported reduced pain and improved functional and patient-reported outcomes after débridement of triangular fibrocartilage complex tears. Most patients after débridement returned to previous work, with few complications. Although some of these cases may require secondary procedures, simple débridement can be performed with suitable satisfactory outcomes for cases with any type of ulnar variance.

  5. 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.)

  6. 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.)

  7. A Case Report of Intra-articular Bee Venom Pharmacopuncture for Partial Tear of Triangular Fibrocartilage Complex

    Directory of Open Access Journals (Sweden)

    Lee, Kwangho

    2009-12-01

    Full Text Available Objective: This case was to report a case of Partial Tear of Triangular Fibrocartilage Complex treated by Intra-articular bee venom Pharmacopuncture. Methods: The patient was treated by Intra-articular bee venom Pharmacopuncture. The Effect of Treatment was evaluated by Visual Analog Scale(VAS and Modified Mayo Wrist Score(Wrist Score. Results & Conclusions: After Treatment, Patient's VAS decreased and Wrist Score increased. For this results, Intra-articular Bee Venom Pharmacopuncture may be effective for Partial Tear of Triangular Fibrocartilage Complex.

  8. Wrist Traction During MR Arthrography Improves Detection of Triangular Fibrocartilage Complex and Intrinsic Ligament Tears and Visibility of Articular Cartilage.

    Science.gov (United States)

    Lee, Ryan K L; Griffith, James F; Ng, Alex W H; Nung, Ryan C H; Yeung, David K W

    2016-01-01

    The purpose of this study was to assess the effects of traction during MR arthrography of the wrist on joint space widening, cartilage visibility, and detection of tears of the triangular fibrocartilage complex (TFCC) and intrinsic ligaments. A prospective study included 40 wrists in 39 patients (25 men, 14 women; mean age, 35 years). MR arthrography was performed with a 3-T MRI system with and without axial traction. Two radiologists independently measured wrist and carpal joint space widths and semiquantitatively graded articular cartilage visibility. Using conventional arthrography as the reference standard and working in consensus, they assessed for the presence of tears of the TFCC, lunotriquetral ligament (LTL), and scapholunate ligament (SLL). Visibility of a tear before traction was compared with visibility after traction. With traction, all joint spaces in the wrist and carpus were significantly widened (change, 0.15-1.01 mm; all p < 0.006). Subjective cartilage visibility of all joint spaces improved after traction (all p ≤ 0.048) except for that of the radioscaphoid space, which was well visualized even before traction. Conventional arthrography depicted 24 TFCC tears, seven LTL tears, and three SLL tears. The accuracy of tear detection improved after traction for the TFCC (98% after traction vs 83% before traction), the LTL (100% vs 88%), and the SLL (100% vs 95%). Tear visibility improved after traction for 54% of TFCC tears, 71% of LTL tears, and 66% of SLL tears. Wrist MR arthrography with axial traction significantly improved the visibility of articular cartilage and the detection and visibility of tears of the TFCC and intrinsic ligaments. The results favor more widespread use of traction during MR arthrography of the wrist.

  9. Ganglion Cyst Associated with Triangular Fibrocartilage Complex Tear That Caused Ulnar Nerve Compression

    Directory of Open Access Journals (Sweden)

    Ugur Anil Bingol, MD

    2015-03-01

    Full Text Available Summary: Ganglions are the most frequently seen soft-tissue tumors in the hand. Nerve compression due to ganglion cysts at the wrist is rare. We report 2 ganglion cysts arising from triangular fibrocartilage complex, one of which caused ulnar nerve compression proximal to the Guyonʼs canal, leading to ulnar neuropathy. Ganglion cysts seem unimportant, and many surgeons refrain from performing a general hand examination.

  10. Evaluation of the triangular fibrocartilage complex tears by arthrography and MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Makoto; Shibata, Yasushi [Hokkaido Kin-i-kyou Central Hospital, Sapporo (Japan); Takahata, Naoji

    1995-08-01

    Arthroscopic or open surgical findings in 21 wrists with chronic ulnar painful lesion were compared both with arthrography and magnetic resonance (MR) imaging results to evaluate the accuracy of the two diagnostic procedures in the detection of triangular fibrocartilage complex (TFCC) lesions. Arthrography investigations were performed for the 20 wrists but one that had allergy for iodine and MR imagings were performed for the recent 12 wrists. Arthrography and magnetic resonance (MR) imaging were almost equally useful for the detection of the TFCC injury and their injury sites. (author).

  11. Computed tomography arthrography using a radial plane view for the detection of triangular fibrocartilage complex foveal tears.

    Science.gov (United States)

    Moritomo, Hisao; Arimitsu, Sayuri; Kubo, Nobuyuki; Masatomi, Takashi; Yukioka, Masao

    2015-02-01

    To classify triangular fibrocartilage complex (TFCC) foveal lesions on the basis of computed tomography (CT) arthrography using a radial plane view and to correlate the CT arthrography results with surgical findings. We also tested the interobserver and intra-observer reliability of the radial plane view. A total of 33 patients with a suspected TFCC foveal tear who had undergone wrist CT arthrography and subsequent surgical exploration were enrolled. We classified the configurations of TFCC foveal lesions into 5 types on the basis of CT arthrography with the radial plane view in which the image slices rotate clockwise centered on the ulnar styloid process. Sensitivity, specificity, and positive predictive values were calculated for each type of foveal lesion in CT arthrography to detect foveal tears. We determined interobserver and intra-observer agreements using kappa statistics. We also compared accuracies with the radial plane views with those with the coronal plane views. Among the tear types on CT arthrography, type 3, a roundish defect at the fovea, and type 4, a large defect at the overall ulnar insertion, had high specificity and positive predictive value for the detection of foveal tears. Specificity and positive predictive values were 90% and 89% for type 3 and 100% and 100% for type 4, respectively, whereas sensitivity was 35% for type 3 and 22% for type 4. Interobserver and intra-observer agreement was substantial and almost perfect, respectively. The radial plane view identified foveal lesion of each palmar and dorsal radioulnar ligament separately, but accuracy results with the radial plane views were not statistically different from those with the coronal plane views. Computed tomography arthrography with a radial plane view exhibited enhanced specificity and positive predictive value when a type 3 or 4 lesion was identified in the detection of a TFCC foveal tear compared with historical controls. Diagnostic II. Copyright © 2015 American Society for

  12. The Role of Wrist Magnetic Resonance Arthrography in Diagnosing Triangular Fibrocartilage Complex Tears; Experience at King Hussein Medical Center, Jordan

    Directory of Open Access Journals (Sweden)

    Asem A. Al-Hiari

    2013-05-01

    Full Text Available Objectives: The aims of the study were to evaluate the role of magnetic resonance arthrography (MRA of the wrist in detecting full-thickness tears of the triangular fibrocartilage complex (TFCC and to compare the results of the magnetic resonance arthrography (MRA with the gold standard arthroscopic findings. Methods:The study was performed at King Hussein Medical Center, Amman, Jordan, between January 2008 and December 2011. A total of 42 patients (35 males and 7 females who had ulnar-sided wrist pain and clinical suspicions of TFCC tears were included in the study. All patients underwent wrist magnetic resonance arthrography (MRA and then a wrist arthroscopy. The results of MRA were compared with the arthroscopic findings. Results: After comparison with the arthroscopic findings, the MRA had three false-negative results (sensitivity = 93% and no false-positive results. A total of 39 patients were able to return to work. Satisfaction was high in 38 of the patients and 33 had satisfactorypain relief. The sensitivity of the wrist MRA in detecting TFCC full-thickness tears was 93% (39, and specificity was 80% (16/20. The overall accuracy of wrist arthroscopy in detecting a full-thickness tear of the TFCC in our study was 85% (29/34. Conclusion: These results illustrate the role of wrist MRA in assessing the TFCC pathology and suggest its use as the first imaging technique, following a plain X-ray, in evaluating patients with chronic ulnar side wrist pain with suspected TFCC injuries.

  13. Clinical experience with arthroscopically-assisted repair of peripheral triangular fibrocartilage complex tears in adolescents--technique and results.

    Science.gov (United States)

    Farr, Sebastian; Zechmann, Ulrike; Ganger, Rudolf; Girsch, Werner

    2015-08-01

    The purpose of this study was to report our preliminary results after arthroscopically-assisted repair of peripheral triangular fibrocartilage complex (TFCC) tears in adolescent patients. All children and adolescents who underwent arthroscopically-assisted repair of a Palmer 1B tear were identified and prospectively evaluated after a mean follow-up of 1.3 years. The postoperative assessment included documentation of clinical parameters, pain score (visual analogue scale, VAS), grip strength and completion of validated outcome scores (Modified Mayo Wrist Score, MMWS; Disabilities of the Arm, Shoulder and Hand Inventory, DASH). A total of 12 patients (four males, eight females) with a mean age of 16.3 years at the time of surgery were evaluated. The mean VAS decreased significantly from 7.0 to 1.7 after the procedure. We observed a significant increase of the MMWS after surgery; however, MMWS was still significantly lower at final follow-up when compared to the contralateral side. A mean postoperative DASH score of 16 indicated an excellent outcome after the procedure. DASH Sports and Work Modules showed fair and good overall outcomes in the short-term, respectively. Grip strength averaged 86 % of the contralateral side at final follow-up, with no significant difference being found between both sides. Arthroscopically-assisted repair of peripheral TFCC tears in adolescents provided predictable pain relief and markedly improved functional outcome scores. Concomitant pathologies may have to be addressed at the same time to eventually achieve a satisfactory outcome. Sports participation, however, may be compromised in the short-term and should therefore be resumed six months postoperatively.

  14. Arthroscopic Diagnosis of the Triangular Fibrocartilage Complex Foveal Tear: A Cadaver Assessment.

    Science.gov (United States)

    Trehan, Samir K; Wall, Lindley B; Calfee, Ryan P; Shen, Tony S; Dy, Christopher J; Yannascoli, Sarah M; Goldfarb, Charles A

    2018-01-25

    To determine whether the arthroscopic hook and trampoline tests are accurate and reliable diagnostic tests for foveal triangular fibrocartilage complex (TFCC) detachment. Wrist arthroscopy was performed on 10 cadaveric upper extremities. Arthroscopic hook and trampoline tests were performed and videos recorded (baseline). The deep foveal TFCC insertion was then sharply detached. Arthroscopic hook and trampoline tests were repeated. Subsequently, the foveal detachment was repaired via an ulnar tunnel technique and the hook test was repeated for a third time. Videos were independently reviewed at 2 time points by 2 fellowship-trained hand surgeons and 1 hand surgery fellow in a randomized and blinded fashion. Hook and trampoline tests were graded as positive or negative. Proportions of categorical variables were compared via 2-tailed Fisher exact test. Inter- and intraobserver reliabilities were assessed via Cohen kappa coefficient. The sensitivity and specificity of the hook test for foveal detachment diagnosis were 90% and 90%, respectively. There was 90% agreement among all 3 observers for the baseline and foveal detachment hook tests. Cohen kappa coefficients for the inter- and intraobserver reliabilities of the hook test were 0.87 and 0.81, respectively. Seventeen percent of trampoline tests were positive at baseline versus 43% after foveal detachment. The trampoline test had 45% agreement between the 3 observers. Cohen kappa coefficients for the inter- and intraobserver reliabilities of the trampoline test were 0.16 and 0.63, respectively. Following ulnar tunnel repair, 20% of hook tests were positive. The hook test is highly sensitive, specific, and reliable for the diagnosis of isolated TFCC foveal detachment. The trampoline test has insufficient reliability to assess foveal detachment. A TFCC foveal repair using an ulnar tunnel technique returns the hook test to baseline. The hook test is a sensitive, specific, and reliable test for the diagnosis of

  15. Intrinsic ligament and triangular fibrocartilage complex tears of the wrist: comparison of MDCT arthrography, conventional 3-T MRI, and MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ryan K.L.; Ng, Alex W.H.; Tong, Cina S.L.; Griffith, James F. [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince Of Wales Hospital, Shatin (China); Tse, W.L.; Wong, C.; Ho, P.C. [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince Of Wales Hospital, Shatin (China); The Chinese University of Hong Kong, Department of Orthopedics, Prince Of Wales Hospital, Shatin (China)

    2013-09-15

    This study compares the diagnostic performance of multidetector CT arthrography (CTA), conventional 3-T MR and MR arthrography (MRA) in detecting intrinsic ligament and triangular fibrocartilage complex (TFCC) tears of the wrist. Ten cadaveric wrists of five male subjects with an average age 49.6 years (range 26-59 years) were evaluated using CTA, conventional 3-T MR and MRA. We assessed the presence of scapholunate ligament (SLL), lunotriquetral ligament (LTL), and TFCC tears using a combination of conventional arthrography and arthroscopy as a gold standard. All images were evaluated in consensus by two musculoskeletal radiologists with sensitivity, specificity, and accuracy being calculated. Sensitivities/specificity/accuracy of CTA, conventional MRI, and MRA were 100 %/100 %/100 %, 66 %/86 %/80 %, 100 %/86 %/90 % for the detection of SLL tear, 100 %/80 %/90 %, 60 %/80 %/70 %, 100 %/80 %/90 % for the detection of LTL tear, and 100 %/100 %/100 %, 100 %/86 %/90 %, 100 %/100 %/100 % for the detection of TFCC tear. Overall CTA had the highest sensitivity, specificity, and accuracy among the three investigations while MRA performed better than conventional MR. CTA also had the highest sensitivity, specificity, and accuracy for identifying which component of the SLL and LTL was torn. Membranous tears of both SLL and LTL were better visualized than dorsal or volar tears on all three imaging modalities. Both CT and MR arthrography have a very high degree of accuracy for diagnosing tears of the SLL, LTL, and TFCC with both being more accurate than conventional MR imaging. (orig.)

  16. Effects on the Distal Radioulnar Joint of Ablation of Triangular Fibrocartilage Complex Tears With Radiofrequency Energy.

    Science.gov (United States)

    Huber, Michaela; Loibl, Markus; Eder, Christoph; Kujat, Richard; Nerlich, Michael; Gehmert, Sebastian

    2016-11-01

    This cadaver study investigated the temperature profile in the wrist joint and distal radioulnar joint (DRUJ) during radiofrequency energy (RFE) application for triangular fibrocartilage complex resection. An arthroscopic partial resection of the triangular fibrocartilage complex using monopolar and bipolar RFE was simulated in 14 cadaver limbs. The temperature was recorded simultaneously in the DRUJ and at 6 other anatomic locations of the wrist during RFE application. The mean temperature in the DRUJ was 43.3 ± 8.2°C for the bipolar system in the ablation mode (60 W) and 30.4 ± 3.4°C for the monopolar system in the cut mode (20 W) after 30 seconds. The highest measured temperature in the DRUJ was 54.3°C for the bipolar system and 68.1°C for the monopolar system. The application of RFE for debridement or resection of the triangular fibrocartilage complex in a clinical setting can induce peak temperatures that might cause damage to the cartilage of the DRUJ. Bipolar systems produce higher mean temperatures than monopolar devices. RFE application increases the mean temperature in the DRUJ after 30 seconds to a level that may jeopardize cartilage tissue. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  17. 3-T direct MR arthrography of the wrist: value of finger trap distraction to assess intrinsic ligament and triangular fibrocartilage complex tears.

    Science.gov (United States)

    Cerny, Milena; Marlois, Romain; Theumann, Nicolas; Bollmann, Christof; Wehrli, Laurent; Richarme, Delphine; Meuli, Reto; Becce, Fabio

    2013-10-01

    To determine the value of applying finger trap distraction during direct MR arthrography of the wrist to assess intrinsic ligament and triangular fibrocartilage complex (TFCC) tears. Twenty consecutive patients were prospectively investigated by three-compartment wrist MR arthrography. Imaging was performed with 3-T scanners using a three-dimensional isotropic (0.4 mm) T1-weighted gradient-recalled echo sequence, with and without finger trap distraction (4 kg). In a blind and independent fashion, two musculoskeletal radiologists measured the width of the scapholunate (SL), lunotriquetral (LT) and ulna-TFC (UTFC) joint spaces. They evaluated the amount of contrast medium within these spaces using a four-point scale, and assessed SL, LT and TFCC tears, as well as the disruption of Gilula's carpal arcs. With finger trap distraction, both readers found a significant increase in width of the SL space (mean Δ = +0.1mm, p ≤ 0.040), and noticed more contrast medium therein (p ≤ 0.035). In contrast, the differences in width of the LT (mean Δ = +0.1 mm, p ≥ 0.057) and UTFC (mean Δ = 0mm, p ≥ 0.728) spaces, as well as the amount of contrast material within these spaces were not statistically significant (p = 0.607 and ≥ 0.157, respectively). Both readers detected more SL (Δ = +1, p = 0.157) and LT (Δ = +2, p = 0.223) tears, although statistical significance was not reached, and Gilula's carpal arcs were more frequently disrupted during finger trap distraction (Δ = +5, p = 0.025). The application of finger trap distraction during direct wrist MR arthrography may enhance both detection and characterisation of SL and LT ligament tears by widening the SL space and increasing the amount of contrast within the SL and LT joint spaces. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  18. 3-T direct MR arthrography of the wrist: Value of finger trap distraction to assess intrinsic ligament and triangular fibrocartilage complex tears

    Energy Technology Data Exchange (ETDEWEB)

    Cerny, Milena; Marlois, Romain [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland); Theumann, Nicolas [Institute of Radiology, Clinique Hirslanden Bois-Cerf, Avenue d’Ouchy 31, 1006 Lausanne (Switzerland); Bollmann, Christof; Wehrli, Laurent [Department of Plastic and Hand Surgery, Clinique Longeraie and Centre Hospitalier Universitaire Vaudois, University of Lausanne, Avenue de la Gare 9, 1003 Lausanne (Switzerland); Richarme, Delphine [Institute of Radiology, Clinique Hirslanden Bois-Cerf, Avenue d’Ouchy 31, 1006 Lausanne (Switzerland); Meuli, Reto [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland); Becce, Fabio, E-mail: fabio.becce@chuv.ch [Department of Diagnostic and Interventional Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Rue du Bugnon 46, 1011 Lausanne (Switzerland)

    2013-10-01

    Purpose: To determine the value of applying finger trap distraction during direct MR arthrography of the wrist to assess intrinsic ligament and triangular fibrocartilage complex (TFCC) tears. Materials and methods: Twenty consecutive patients were prospectively investigated by three-compartment wrist MR arthrography. Imaging was performed with 3-T scanners using a three-dimensional isotropic (0.4 mm) T1-weighted gradient-recalled echo sequence, with and without finger trap distraction (4 kg). In a blind and independent fashion, two musculoskeletal radiologists measured the width of the scapholunate (SL), lunotriquetral (LT) and ulna-TFC (UTFC) joint spaces. They evaluated the amount of contrast medium within these spaces using a four-point scale, and assessed SL, LT and TFCC tears, as well as the disruption of Gilula's carpal arcs. Results: With finger trap distraction, both readers found a significant increase in width of the SL space (mean Δ = +0.1 mm, p ≤ 0.040), and noticed more contrast medium therein (p ≤ 0.035). In contrast, the differences in width of the LT (mean Δ = +0.1 mm, p ≥ 0.057) and UTFC (mean Δ = 0 mm, p ≥ 0.728) spaces, as well as the amount of contrast material within these spaces were not statistically significant (p = 0.607 and ≥0.157, respectively). Both readers detected more SL (Δ = +1, p = 0.157) and LT (Δ = +2, p = 0.223) tears, although statistical significance was not reached, and Gilula's carpal arcs were more frequently disrupted during finger trap distraction (Δ = +5, p = 0.025). Conclusion: The application of finger trap distraction during direct wrist MR arthrography may enhance both detection and characterisation of SL and LT ligament tears by widening the SL space and increasing the amount of contrast within the SL and LT joint spaces.

  19. Biomechanical Analysis of All-Inside, Arthroscopic Suture Repair Versus Extensor Retinaculum Capsulorrhaphy for Triangular Fibrocartilage Complex Tears With Instability.

    Science.gov (United States)

    Patel, Amar A; Alhandi, Ali A; Milne, Edward; Dy, Christopher J; Latta, Loren L; Ouellette, E Anne

    2016-03-01

    To assess ulnocarpal joint stability after treatment of a peripheral triangular fibrocartilage complex (TFCC) injury with all-inside arthroscopic suture repair (SR), extensor retinaculum capsulorrhaphy with the Herbert sling (HS), and a combination of both (SR+HS). Twelve fresh-frozen, age-matched, upper-extremity specimens intact from the distal humerus were prepared. Nondestructive mechanical testing was performed to assess native ulnocarpal joint stability and load-displacement curves were recorded. A peripheral, ulnar-sided TFCC injury was created with arthroscopic assistance, and mechanical testing was performed. Each specimen was treated with SR or HS and testing was repeated. The 6 specimens treated with SR were then treated with HS (SR+HS), and testing was repeated. We used paired Student t tests for statistical analysis within cohorts. For all cohorts, there was an average increase in ulnar translation after the creation of a peripheral TFCC injury and an average decrease after repair. Herbert sling decreased translation by 21%, SR decreased translation by 12%, and SR+HS decreased translation by 26%. Suture repair plus HS and HS reduce ulnar translation the most after a peripheral TFCC injury, followed by SR alone. Ulnocarpal joint stability should be assessed clinically in patients with peripheral TFCC injury, and consideration should be made for using extensor capsulorrhaphy in isolation or as an adjunct to SR as a treatment option. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  20. Arthroscopic-Assisted Triangular Fibrocartilage Complex Reconstruction.

    Science.gov (United States)

    Chu-Kay Mak, Michael; Ho, Pak-Cheong

    2017-11-01

    Injury of the triangular fibrocartilage complex (TFCC) is a common cause of ulnar-sided wrist pain. Volar and dorsal radioulnar ligaments and their foveal insertion are the most important stabilizing components of the TFCC. In irreparable tears, anatomic reconstruction of the TFCC aims to restore normal biomechanics and stability of the distal radioulnar joint. We proposed a novel arthroscopic-assisted technique using a palmaris longus tendon graft. Arthroscopic-assisted TFCC reconstruction is a safe and effective approach with outcomes comparable to conventional open reconstruction and may result in a better range of motion from minimizing soft tissue dissection and subsequent scarring. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Triangular fibrocartilage complex injury treated with prolotherapy

    Directory of Open Access Journals (Sweden)

    Serdar Kesikburun

    2016-06-01

    Full Text Available Triangular fibrocartilage complex has a crucial role in stability and functionality of the wrist. Traumatic or degenerative injury of the triangular fibrocartilage complex is a common cause of ulnar side wrist pain. Arthroscopic treatment has been offered in chronic triangular fibrocartilage complex injury. A 19-year old male patient presented with pain at ulnar side of the wrist. He was diagnosed as having triangular fibrocartilage complex injury after assessment with MR imaging. The patients who did not benefit from drugs underwent prolotherapy three times. After treatment, he had pain relief and reported that he could use his wrist better. In this case, triangular fibrocartilage complex injury improved with prolotherapy and arthroscopic treatment was not required. Further clinical trials are needed to show better the role of prolotherapy in the treatment of triangular fibrocartilage complex injury. [Cukurova Med J 2016; 41(2.000: 403-405

  2. Clinical and functional outcome of open primary repair of triangular fibrocartilage complex tears associated with distal radius fractures.

    Science.gov (United States)

    Johandi, Faisal; Sechachalam, Sreedharan

    2017-01-01

    We evaluate the clinical and functional outcome of open primary repair of acute TFCC tears in distal radius fracture, when there is gross intraoperative distal radioulnar joint (DRUJ) instability after fixation of the distal radius, in the absence of an ulnar styloid fracture or when the ulnar fracture fragment is too small to be fixed. A retrospective review of our institution's distal radius fracture database over a 4-year period (January 2010 to December 2013). A total of 12 (1.38%) out of 3379 patients had an open TFCC repair in the same setting as fixation of distal radius. Assessment of outcome involved the analysis of objective and subjective clinical and functional outcomes. All patient regained Activities of Daily Living (ADL) independence; eleven out of 12 patients (91.7%) returned to pre-injury function and 8 out of 11 patients (72.7%) returned to their jobs. DRUJ stability was preserved in 10 patients (83.3%) with 10 patients (83.3%) having grip strength of at least 50%, compared to the uninjured hand, and 7 (58.3%) with grip strength of more than or equal to 75%. Complications of surgery identified can be classified into 4 broad categories: infection, neurological complications, persistent DRUJ instability and prolonged pain. The authors believe a primary open repair of the TFCC should be considered when patients present with instability during intra-operative DRUJ ballottement test after distal radius fixation, in the absence of an ulnar styloid fracture or when the ulnar fracture fragment is too small to be fixed.

  3. Chronologic and Geographic Trends of Triangular Fibrocartilage Complex Repair.

    Science.gov (United States)

    Saito, Taichi; Sterbenz, Jennifer M; Chung, Kevin C

    2017-11-01

    This article shows trends in triangular fibrocartilage complex (TFCC) repair since 1990 by geographic area and year. The repair methods presented in the literature were inside-out, outside-in, all-inside, and open repair. The outside-in technique was reported most often for ulnar-side tears, whereas the inside-out technique was reported most frequently for radial-side tears. Recently, a foveal reattachment technique for ulnar-side tears has garnered attention and has been reported with increasing frequency, especially in Asia, because the deepest portion of TFCC, attached to fovea, plays a key role in stabilizing the distal radioulnar joint. Understanding these trends can help clinicians best treat TFCC tears. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. MR imaging of the traumatic triangular fibrocartilaginous complex tear

    Science.gov (United States)

    Griffith, James F.; Fung, Cindy S. Y.; Lee, Ryan K. L.; Tong, Cina S. L.; Wong, Clara W. Y.; Tse, Wing Lim; Ho, Pak Cheong

    2017-01-01

    Triangular fibrocartilage complex is a major stabilizer of the distal radioulnar joint (DRUJ). However, triangular fibrocartilage complex (TFCC) tear is difficult to be diagnosed on MRI for its intrinsic small and thin structure with complex anatomy. The purpose of this article is to review the anatomy of TFCC, state of art MRI imaging technique, normal appearance and features of tear on MRI according to the Palmar’s classification. Atypical tear and limitations of MRI in diagnosis of TFCC tear are also discussed. PMID:28932701

  5. Histological assessment of the triangular fibrocartilage complex.

    Science.gov (United States)

    Semisch, M; Hagert, E; Garcia-Elias, M; Lluch, A; Rein, S

    2016-06-01

    The morphological structure of the seven components of triangular fibrocartilage complexes of 11 cadaver wrists of elderly people was assessed microscopically, after staining with Hematoxylin-Eosin and Elastica van Gieson. The articular disc consisted of tight interlaced fibrocartilage without blood vessels except in its ulnar part. Volar and dorsal radioulnar ligaments showed densely parallel collagen bundles. The subsheath of the extensor carpi ulnaris muscle, the ulnotriquetral and ulnolunate ligament showed mainly mixed tight and loose parallel tissue. The ulnolunate ligament contained tighter parallel collagen bundles and clearly less elastic fibres than the ulnotriquetral ligament. The ulnocarpal meniscoid had an irregular morphological composition and loose connective tissue predominated. The structure of the articular disc indicates a buffering function. The tight structure of radioulnar and ulnolunate ligaments reflects a central stabilizing role, whereas the ulnotriquetral ligament and ulnocarpal meniscoid have less stabilizing functions. © The Author(s) 2015.

  6. MR Imaging of the Triangular Fibrocartilage Complex.

    Science.gov (United States)

    Cody, Michael E; Nakamura, David T; Small, Kirstin M; Yoshioka, Hiroshi

    2015-08-01

    MR imaging has emerged as the mainstay in imaging internal derangement of the soft tissues of the musculoskeletal system largely because of superior contrast resolution. The complex geometry and diminutive size of the triangular fibrocartilage complex (TFCC) and its constituent structures can make optimal imaging of the TFCC challenging; therefore, production of clinically useful images requires careful optimization of image acquisition parameters. This article provides a foundation for advanced TFCC imaging including factors to optimize magnetic resonance images, arthrography, detailed anatomy, and classification of injury. In addition, clinical presentations and treatments for TFCC injury are briefly considered. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. The Degeneration of Meniscus Roots Is Accompanied by Fibrocartilage Formation, Which May Precede Meniscus Root Tears in Osteoarthritic Knees.

    Science.gov (United States)

    Park, Do Young; Min, Byoung-Hyun; Choi, Byung Hyune; Kim, Young Jick; Kim, Mijin; Suh-Kim, Haeyoung; Kim, Joon Ho

    2015-12-01

    Fibrocartilage metaplasia in tendons and ligaments is an adaptation to compression as well as a pathological feature during degeneration. Medial meniscus posterior roots are unique ligaments that resist multidirectional forces, including compression. To characterize the degeneration of medial meniscus posterior root tears in osteoarthritic knees, with an emphasis on fibrocartilage and calcification. Cross-sectional study; Level of evidence, 3. Samples of medial meniscus posterior roots were harvested from cadaveric specimens and patients during knee replacement surgery and grouped as follows: normal reference, no tear, partial tear, and complete tear. Degeneration was analyzed with histology, immunohistochemistry, and real-time polymerase chain reaction. Uniaxial tensile tests were performed on specimens with and without fibrocartilage. Quantifiable data were statistically analyzed by the Kruskal-Wallis test with the Dunn comparison test. Thirty, 28, and 42 samples harvested from 99 patients were allocated into the no tear, partial tear, and complete tear groups, respectively. Mean modified Bonar tendinopathy scores for each group were 3.97, 9.31, and 14.15, respectively, showing a higher degree of degeneration associated with the extent of the tear (P fibrocartilage according to the extent of the tear. Tear margins revealed fibrocartilage in 59.3% of partial tear samples and 76.2% of complete tear samples, with a distinctive cleavage-like shape. Root tears with a similar shape were induced within fibrocartilaginous areas during uniaxial tensile testing. Even in the no tear group, 56.7% of samples showed fibrocartilage in the anterior margin of the root, adjacent to the meniscus. An increased stained area of calcification and expression of the ectonucleotide pyrophosphatase/phosphodiesterase 1 gene were observed in the complete tear group compared with the no tear group (P Fibrocartilage and calcification increased in medial meniscus posterior roots, associated

  8. Wrist stability after experimental traumatic triangular fibrocartilage complex lesions

    DEFF Research Database (Denmark)

    Munk, Bo; Jensen, Steen Lund; Olsen, Bo Sanderhoff

    2005-01-01

    The aim of this study was to evaluate changes in stability of the wrist after experimental traumatic triangular fibrocartilage complex lesions.......The aim of this study was to evaluate changes in stability of the wrist after experimental traumatic triangular fibrocartilage complex lesions....

  9. MRI on the tear of the triangular fibrocartilage of the wrist

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Yoko; Sasaki, Taisuke; Sasaki, Yukio; Nishi, Naoko; Yodono, Hiraku; Takekawa, Shoichi; Toh, Satoshi; Harata, Seikou (Hirosaki Univ., Aomori (Japan). School of Medicine)

    1992-07-01

    MRI of the wrist joints in the normal volunteers and patients with triangular fibrocartilage (TFC) injury was performed and usefulness of MRI of TFC injury was discussed. Small FOV and thin slice thickness were selected. Normal TFCs were shown as low signal intensity areas. Injury of TFC was demonstrated as increased signal intensity areas. Diagnosis of TFC injury should be made after considering their ages and symptoms because TFC shows degenerative change with aging. The sensitivity, specificity and accuracy of MRI in the detection of TFC tears were 80.0%, 81.8% and 81.0% respectively. MRI is considered to be a non-invasive good modality to demonstrate TFC tears. (author).

  10. [Arthroscopically assisted transcapsular refixation of the triangular fibrocartilage complex of the wrist].

    Science.gov (United States)

    Pillukat, T; Fuhrmann, R A; Windolf, J; van Schoonhoven, J

    2016-08-01

    Refixation of the triangular fibrocartilage complex (TFCC) to the ulnar capsule of the wrist. Distal TFCC tears without instability, proximal TFCC intact. Loose ulnar TFCC attachment without tear or instability. Peripheral TFCC tears with instability of the distal radioulnar joint (DRUJ). Complex or proximal tears of the TFCC. Isolated, central degenerative tears without healing potential. Arthroscopically guided, minimally invasive suture of the TFCC to the base of the sixth extensor compartment. Above elbow plaster splint, 70° flexion of the elbow joint, 45° supination for 6 weeks. Skin suture removal after 2 weeks. No physiotherapy to extend pronation and supination during the first 3 months. In an ongoing long-term study, 7 of 31 patients who underwent transcapsular refixation of the TFCC between 1 January 2003 and 31 December 2010 were evaluated after an average follow-up interval of 116 ± 34 months (range 68-152 months). All patients demonstrated an almost nearly unrestricted range of wrist motion and grip strength compared to the unaffected side. All distal radioulnar joints were stable. On the visual analogue scale (VAS 0-10), pain at rest was 1 ± 1 (range 0-2) and pain during exercise 2 ± 2 (range 0-5); the DASH score averaged 10 ± 14 points (range 0-39 points). All patients were satisfied. The modified Mayo wrist score showed four excellent, two good, and one fair result. These results correspond to the results of other series. Transcapsular refixation is a reliable, technically simple procedure in cases with ulnar-sided TFCC tears without instability leading to good results.

  11. Indications, techniques, and outcomes of arthroscopic repair of scapholunate ligament and triangular fibrocartilage complex.

    Science.gov (United States)

    Mathoulin, C L

    2017-07-01

    This review includes updated understanding of the roles of intrinsic and extrinsic carpal ligaments in scapholunate instability and details the author's experience of indications, arthroscopic repair methods, and outcomes of treating the instability. A classification on triangular fibrocartilage complex injuries is reviewed, followed by author's indications, methods, and outcomes of arthroscopic repair of triangular fibrocartilage complex injuries.

  12. Arthroscopic Management of Triangular Fibrocartilage Complex Peripheral Injury.

    Science.gov (United States)

    Haugstvedt, Jan Ragnar; Søreide, Endre

    2017-11-01

    Patients suffering from ulnar-sided wrist pain after trauma may develop tenderness, clicking, a positive fovea sign, or instability of the distal radioulnar joint. If the pain is persistent, conservative treatment does not help, and the patient agrees to surgery, arthroscopy may reveal a triangular fibrocartilage complex (TFCC) injury with capsular detachment, foveal avulsion, or a combination thereof. Capsular reattachment is possible using an arthroscopic assisted technique. The reattachment can be performed with an inside-out, outside-in, or all-inside technique, providing good to excellent results, which tend to persist over time, in 60% to 90% of cases. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Arthroscopic Management of Triangular Fibrocartilage Complex Foveal Injury.

    Science.gov (United States)

    Fujio, Keiji

    2017-11-01

    The deep component of triangular fibrocartilage complex (TFCC) inserts onto the fovea of the ulnar head. This component is critical to provide distal radioulnar joint stability. The surgical techniques and results of transosseous inside-out TFCC foveal repair are discussed. The rewarding results encouraged the repair of TFCC to the fovea arthroscopically. Although the results are good, the factors of age (traumatic or degenerative) and quality of stump and TFCC proper, which relate to the results should be considered in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Diagnosis of triangular fibrocartilage complex injury using arthrography and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Kiyonobu; Soejima, Osamu; Naito, Masatoshi [Fukuoka Univ. (Japan). School of Medicine

    2001-09-01

    Twenty patients (twenty-one wrists) with chronic ulnar wrist pain who had undergone radiocarpal arthrography and MRI before arthroscopic examination were evaluated to determine the usefulness of these preoperative diagnostic procedures (arthrogrphy and MRI) for the detection of triangular fibrocartilage complex (TFCC) injury. Based on the arthroscopic findings, the sensitivity and specificity of arthrography were 63% and 100% respectively for detecting TFCC lesions, while they were 68% and 50% respectively for MRI. Although no significant superiority was observed between arthrography and MRI in this study, further improrumchts in the preoperative diagnostic procedures are still needed in order to more accurately detect TFCC injuries. (author)

  15. [Instability of the distal radioulnar joint: Treatment options for ulnar lesions of the triangular fibrocartilage complex].

    Science.gov (United States)

    Spies, C K; Prommersberger, K J; Langer, M; Müller, L P; Hahn, P; Unglaub, F

    2015-08-01

    Injuries of the triangular fibrocartilage complex (TFCC) may be fatal to the distal radioulnar joint (DRUJ). This structure is one of the crucial stabilizers and guarantees unrestricted pronosupination of the forearm. A systematic examination is mandatory to diagnose DRUJ instability reliably. A clinical examination in comparison to the contralateral side is obligatory. Plain radiographs are required to exclude osseous lesions or deformities. Computed tomography of both wrists in neutral, pronation and supination is necessary to verify DRUJ instability in ambiguous situations. Based on a systematic examination wrist and DRUJ arthroscopy identify lesions clearly. Injuries of the radioulnar ligaments which entail DRUJ instability, should be reconstructed preferably anatomically. Ulnar-sided TFCC lesions may often cause DRUJ instability. Osseous ligament avulsions are mostly treated osteosynthetically. Ligament tears may be refixated using anchor or transosseous sutures. Tendon transplants are necessary for an anatomical reconstruction in cases of irreparable ruptures.

  16. The performance of magnetic resonance imaging in the detection of triangular fibrocartilage complex injury: a meta-analysis.

    Science.gov (United States)

    Wang, Z X; Chen, S L; Wang, Q Q; Liu, B; Zhu, J; Shen, J

    2015-06-01

    The aim of this study was to evaluate the accuracy of magnetic resonance imaging in the detection of triangular fibrocartilage complex injury through a meta-analysis. A comprehensive literature search was conducted before 1 April 2014. All studies comparing magnetic resonance imaging results with arthroscopy or open surgery findings were reviewed, and 25 studies that satisfied the eligibility criteria were included. Data were pooled to yield pooled sensitivity and specificity, which were respectively 0.83 and 0.82. In detection of central and peripheral tears, magnetic resonance imaging had respectively a pooled sensitivity of 0.90 and 0.88 and a pooled specificity of 0.97 and 0.97. Six high-quality studies using Ringler's recommended magnetic resonance imaging parameters were selected for analysis to determine whether optimal imaging protocols yielded better results. The pooled sensitivity and specificity of these six studies were 0.92 and 0.82, respectively. The overall accuracy of magnetic resonance imaging was acceptable. For peripheral tears, the pooled data showed a relatively high accuracy. Magnetic resonance imaging with appropriate parameters are an ideal method for diagnosing different types of triangular fibrocartilage complex tears. © The Author(s) 2015.

  17. MR morphology of triangular fibrocartilage complex: correlation with quantitative MR and biomechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Won C.; Chang, Eric Y.; Chung, Christine B. [VA San Diego Healthcare System, Radiology Service, San Diego, CA (United States); University of California-San Diego, Department of Radiology, San Diego, CA (United States); Ruangchaijatuporn, Thumanoon [Mahidol University, Department of Diagnostic and Therapeutic Radiology, Faculty of Medicine Ramathibodi Hospital, Rachathewi, Bangkok (Thailand); Biswas, Reni; Du, Jiang; Statum, Sheronda [University of California-San Diego, Department of Radiology, San Diego, CA (United States)

    2016-04-15

    To evaluate pathology of the triangular fibrocartilage complex (TFCC) using high-resolution morphologic magnetic resonance (MR) imaging, and compare with quantitative MR and biomechanical properties. Five cadaveric wrists (22-70 years) were imaged at 3 T using morphologic (proton density weighted spin echo, PD FS, and 3D spoiled gradient echo, 3D SPGR) and quantitative MR sequences to determine T2 and T1rho properties. In eight geographic regions, morphology of TFC disc and laminae were evaluated for pathology and quantitative MR values. Samples were disarticulated and biomechanical indentation testing was performed on the distal surface of the TFC disc. On morphologic PD SE images, TFC disc pathology included degeneration and tears, while that of the laminae included degeneration, degeneration with superimposed tear, mucinous transformation, and globular calcification. Punctate calcifications were highly visible on 3D SPGR images and found only in pathologic regions. Disc pathology occurred more frequently in proximal regions of the disc than distal regions. Quantitative MR values were lowest in normal samples, and generally higher in pathologic regions. Biomechanical testing demonstrated an inverse relationship, with indentation modulus being high in normal regions with low MR values. The laminae studied were mostly pathologic, and additional normal samples are needed to discern quantitative changes. These results show technical feasibility of morphologic MR, quantitative MR, and biomechanical techniques to characterize pathology of the TFCC. Quantitative MRI may be a suitable surrogate marker of soft tissue mechanical properties, and a useful adjunct to conventional morphologic MR techniques. (orig.)

  18. MR morphology of triangular fibrocartilage complex: correlation with quantitative MR and biomechanical properties

    International Nuclear Information System (INIS)

    Bae, Won C.; Chang, Eric Y.; Chung, Christine B.; Ruangchaijatuporn, Thumanoon; Biswas, Reni; Du, Jiang; Statum, Sheronda

    2016-01-01

    To evaluate pathology of the triangular fibrocartilage complex (TFCC) using high-resolution morphologic magnetic resonance (MR) imaging, and compare with quantitative MR and biomechanical properties. Five cadaveric wrists (22-70 years) were imaged at 3 T using morphologic (proton density weighted spin echo, PD FS, and 3D spoiled gradient echo, 3D SPGR) and quantitative MR sequences to determine T2 and T1rho properties. In eight geographic regions, morphology of TFC disc and laminae were evaluated for pathology and quantitative MR values. Samples were disarticulated and biomechanical indentation testing was performed on the distal surface of the TFC disc. On morphologic PD SE images, TFC disc pathology included degeneration and tears, while that of the laminae included degeneration, degeneration with superimposed tear, mucinous transformation, and globular calcification. Punctate calcifications were highly visible on 3D SPGR images and found only in pathologic regions. Disc pathology occurred more frequently in proximal regions of the disc than distal regions. Quantitative MR values were lowest in normal samples, and generally higher in pathologic regions. Biomechanical testing demonstrated an inverse relationship, with indentation modulus being high in normal regions with low MR values. The laminae studied were mostly pathologic, and additional normal samples are needed to discern quantitative changes. These results show technical feasibility of morphologic MR, quantitative MR, and biomechanical techniques to characterize pathology of the TFCC. Quantitative MRI may be a suitable surrogate marker of soft tissue mechanical properties, and a useful adjunct to conventional morphologic MR techniques. (orig.)

  19. MR morphology of triangular fibrocartilage complex: correlation with quantitative MR and biomechanical properties.

    Science.gov (United States)

    Bae, Won C; Ruangchaijatuporn, Thumanoon; Chang, Eric Y; Biswas, Reni; Du, Jiang; Statum, Sheronda; Chung, Christine B

    2016-04-01

    To evaluate pathology of the triangular fibrocartilage complex (TFCC) using high-resolution morphologic magnetic resonance (MR) imaging, and compare with quantitative MR and biomechanical properties. Five cadaveric wrists (22-70 years) were imaged at 3 T using morphologic (proton density weighted spin echo, PD FS, and 3D spoiled gradient echo, 3D SPGR) and quantitative MR sequences to determine T2 and T1rho properties. In eight geographic regions, morphology of TFC disc and laminae were evaluated for pathology and quantitative MR values. Samples were disarticulated and biomechanical indentation testing was performed on the distal surface of the TFC disc. On morphologic PD SE images, TFC disc pathology included degeneration and tears, while that of the laminae included degeneration, degeneration with superimposed tear, mucinous transformation, and globular calcification. Punctate calcifications were highly visible on 3D SPGR images and found only in pathologic regions. Disc pathology occurred more frequently in proximal regions of the disc than distal regions. Quantitative MR values were lowest in normal samples, and generally higher in pathologic regions. Biomechanical testing demonstrated an inverse relationship, with indentation modulus being high in normal regions with low MR values. The laminae studied were mostly pathologic, and additional normal samples are needed to discern quantitative changes. These results show technical feasibility of morphologic MR, quantitative MR, and biomechanical techniques to characterize pathology of the TFCC. Quantitative MRI may be a suitable surrogate marker of soft tissue mechanical properties, and a useful adjunct to conventional morphologic MR techniques.

  20. High-resolution 3-T MRI of the triangular fibrocartilage complex in the wrist: injury pattern and MR features

    Energy Technology Data Exchange (ETDEWEB)

    Zhan, Huili; Liu, Yue; Zhang, Heng [Peking University Fourth School of Clinical Medicine, Department of Radiology, Beijing (China); Zhang, Huibo [Beijing Chaoyang Hospital of Capital Medical University, Department of Radiology, Beijing (China); Bai, Rongjie; Qian, Zhanhua [Peking University Fourth School of Clinical Medicine, Department of Radiology, Beijing (China); Beijing Institute of Traumatology and Orthopedics, Department of Radiology, Beijing Jishuitan Hospital, Beijing (China); Yin, Yuming [Radiology Associates, LLP, Corpus Christi, TX (United States)

    2017-12-15

    To investigate if using high-resolution 3-T MRI can identify additional injuries of the triangular fibrocartilage complex (TFCC) beyond the Palmer classification. Eighty-six patients with surgically proven TFCC injury were included in this study. All patients underwent high-resolution 3-T MRI of the injured wrist. The MR imaging features of TFCC were analyzed according to the Palmer classification. According to the Palmer classification, 69 patients could be classified as having Palmer injuries (52 had traumatic tears and 17 had degenerative tears). There were 17 patients whose injuries could not be classified according to the Palmer classification: 13 had volar or dorsal capsular TFC detachment and 4 had a horizontal tear of the articular disk. Using high-resolution 3-T MRI, we have not only found all the TFCC injuries described in the Palmer classification, additional injury types were found in this study, including horizontal tear of the TFC and capsular TFC detachment. We propose the modified Palmer classification and add the injury types that were not included in the original Palmer classification. (orig.)

  1. High-resolution 3-T MRI of the triangular fibrocartilage complex in the wrist: injury pattern and MR features

    International Nuclear Information System (INIS)

    Zhan, Huili; Liu, Yue; Zhang, Heng; Zhang, Huibo; Bai, Rongjie; Qian, Zhanhua; Yin, Yuming

    2017-01-01

    To investigate if using high-resolution 3-T MRI can identify additional injuries of the triangular fibrocartilage complex (TFCC) beyond the Palmer classification. Eighty-six patients with surgically proven TFCC injury were included in this study. All patients underwent high-resolution 3-T MRI of the injured wrist. The MR imaging features of TFCC were analyzed according to the Palmer classification. According to the Palmer classification, 69 patients could be classified as having Palmer injuries (52 had traumatic tears and 17 had degenerative tears). There were 17 patients whose injuries could not be classified according to the Palmer classification: 13 had volar or dorsal capsular TFC detachment and 4 had a horizontal tear of the articular disk. Using high-resolution 3-T MRI, we have not only found all the TFCC injuries described in the Palmer classification, additional injury types were found in this study, including horizontal tear of the TFC and capsular TFC detachment. We propose the modified Palmer classification and add the injury types that were not included in the original Palmer classification. (orig.)

  2. High-resolution 3-T MRI of the triangular fibrocartilage complex in the wrist: injury pattern and MR features.

    Science.gov (United States)

    Zhan, Huili; Zhang, Huibo; Bai, Rongjie; Qian, Zhanhua; Liu, Yue; Zhang, Heng; Yin, Yuming

    2017-12-01

    To investigate if using high-resolution 3-T MRI can identify additional injuries of the triangular fibrocartilage complex (TFCC) beyond the Palmer classification. Eighty-six patients with surgically proven TFCC injury were included in this study. All patients underwent high-resolution 3-T MRI of the injured wrist. The MR imaging features of TFCC were analyzed according to the Palmer classification. According to the Palmer classification, 69 patients could be classified as having Palmer injuries (52 had traumatic tears and 17 had degenerative tears). There were 17 patients whose injuries could not be classified according to the Palmer classification: 13 had volar or dorsal capsular TFC detachment and 4 had a horizontal tear of the articular disk. Using high-resolution 3-T MRI, we have not only found all the TFCC injuries described in the Palmer classification, additional injury types were found in this study, including horizontal tear of the TFC and capsular TFC detachment. We propose the modified Palmer classification and add the injury types that were not included in the original Palmer classification.

  3. Arthroscopic-assisted repair of triangular fibrocartilage complex foveal avulsion in distal radioulnar joint injury

    Science.gov (United States)

    Woo, Sung Jong; Jegal, Midum; Park, Min Jong

    2016-01-01

    Background: Disruption of the triangular fibrocartilage complex (TFCC) foveal insertion can lead to distal radioulnar joint (DRUJ) instability accompanied by ulnar-sided pain, weakness, snapping, and limited forearm rotation. We investigated the clinical outcomes of patients with TFCC foveal tears treated with arthroscopic-assisted repair. Materials and Methods: Twelve patients underwent foveal repair of avulsed TFCC with the assistance of arthroscopy between 2011 and 2013. These patients were followed up for an average of 19 months (range 14–25 months). The avulsed TFCC were reattached to the fovea using a transosseous pull-out suture or a knotless suture anchor. At the final followup, the range of motion, grip strength and DRUJ stability were measured as objective outcomes. Subjective outcomes were assessed using the Visual Analog Scale (VAS) for pain, patient rated wrist evaluation (PRWE), Disabilities of the Arm, Shoulder and Hand questionnaire (DASH score) and return to work. Results: Based on the DRUJ stress test, 5 patients had normal stability and 7 patients showed mild laxity as compared with the contralateral side. Postoperatively, the mean range of pronation supination increased from 141° to 166°, and the mean VAS score for pain decreased from 5.3 to 1.7 significantly. The PRWE and DASH questionnaires also showed significant functional improvement. All patients were able to return to their jobs. However, two patients complained of persistent pain. Conclusions: Arthroscopically assisted repair of TFCC foveal injury can provide significant pain relief, functional improvement and restoration of DRUJ stability. PMID:27293286

  4. Magnetic resonance imaging of the triangular fibrocartilage complex. Usefulness of the fat suppression MRI

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Toshiyasu [Fujita Health Univ., Nagoya (Japan). Second Hospital; Yabe, Yutaka; Horiuchi, Yukio; Kikuchi, Yoshito; Makita, Satoo

    1996-08-01

    Advances in magnetic resonance imaging (MRI) now allow for the visualization of small structures, such as the triangular fibrocartilage complex (TFCC) of the wrist. Recent investigators suggested that MRI is useful in delineation of the TFCC itself and its abnormality, and supported that diagnostic value of MRI for the TFCC tears is almost equal to those of arthrography and arthroscopy. In contrast, there were several reports that representation of the TFCC in MRI was less worth than in arthrography. Further, it was reported that MRI was not useful because abnormal findings existed at normal volunteers` wrists. Recent development of the pulse sequence is remarkable, such as gradient echo, fast spin echo and fat suppression method. However, as the previous MR studies of the TFCC mainly using conventional spin echo pulse sequence, there were a few comparison of each pulse sequence and we do not know how each pulse sequence delineates the TFCC. Therefore, we studied MRI of the TFCC using several pulse sequence in normal volunteers, and compared MR slices of the TFCC with corresponding histological sections to evaluate shape detectability of MRI. (J.P.N.)

  5. The correlation of initial radiographic characteristics of distal radius fractures and injuries of the triangular fibrocartilage complex.

    Science.gov (United States)

    Kasapinova, K; Kamiloski, V

    2016-06-01

    Our purpose was to determine the correlation of initial radiographic parameters of a distal radius fracture with an injury of the triangular fibrocartilage complex. In a prospective study, 85 patients with surgically treated distal radius fractures were included. Wrist arthroscopy was used to identify and classify triangular fibrocartilage complex lesions. The initial radial length and angulation, dorsal angulation, ulnar variance and distal radioulnar distance were measured. Wrist arthroscopy identified a triangular fibrocartilage complex lesion in 45 patients. Statistical analysis did not identify a correlation with any single radiographic parameter of the distal radius fractures with the associated triangular fibrocartilage complex injuries. The initial radiograph of a distal radius fracture does not predict a triangular fibrocartilage complex injury. III. © The Author(s) 2016.

  6. MAGNETIC RESONANCE IMAGING FOR TRIQUETROUS FIBROCARTILAGE COMPLEX DAMAGES AT WRIST JOINT INJURIES

    Directory of Open Access Journals (Sweden)

    E. A. Kadubovskaya

    2010-01-01

    Full Text Available A brief review of the literature on normal anatomy and pathological changes of trihedral fibro-cartilage complex of wrist. The authors described in detail a method of wrist MRI, MR-image of normal and damaged articular disk, considered possible variants for his injuries. The results of MRI of wrist in 110 people including 40 patients with suspected damage were analyzed. At present MRI is the only available non-invasive method for diagnosing injuries of intraarticular structures, in particular trihedral fibro-cartilage complex.

  7. [Classification and MR imaging of triangular fibrocartilage complex lesions].

    Science.gov (United States)

    Zhan, H L; Liu, Y; Bai, R J; Qian, Z H; Ye, W; Li, Y X; Wu, B D

    2016-06-07

    To explore the MRI characteristics of injuries of triangular fibrocartilage complex (TFCC), and provide imaging basis for the early diagnosis and treatment of the injuries. A total of 10 healthy volunteers without wrist injuries and 200 patients from Beijing Jishuitan Hospital who complained ulnar-sided wrist pain and were highly suspected as the injury of TFCC underwent the wrist magnetic resonance examination. All subjects were in a prone position and underwent examination on coronal T1WI scan and PD-FS on 3 planes respectively. Then the MRI characteristics of 3 healthy volunteers and 67 patients with TFCC injuries that confirmed by operation were analyzed. According to the comparative analysis of normal anatomy and Palmer classification, the injuries were classified and MRI features of different types of injuries were analyzed. At last, imaging findings were compared with surgical results. Three healthy volunteers without injuries showed mainly in low signal intensity on T1WI and PD-FS images. According to Palmer classification, there were 52 traumatic injuries (ⅠA 9, ⅠB 25, ⅠC 3, ⅠD 13, In addition, 1 has central perforation and ulnar avulsion and 1 has ulnar and radial injuries simultaneously) and 15 degenerative injuries (ⅡA 5, ⅡB 1, ⅡC 2 , ⅡD 1 , ⅡE 6) among 67 patients. The central perforation mainly demonstrated as linear high signal perpendicular to the disk, and run in a sagittal line. The ulnar, distal, and radial avulsion mainly showed the injuries were irregular, the structures were ambiguous, and there was high signal intensity in the injured structures on PD-FS. Degenerative injuries demonstrated the irregularity of TFC and heterogeneous signals on PD-FS. There were mixed intermediate-high signals and changes in the articular cartilage of lunate and ulna, high signal in the lunotriquetral ligament and ulnocarpal or radioulnar arthritis. MRI can demonstrate the anatomy of TFCC accurately, evaluate and make the general classification

  8. Functionality after arthroscopic debridement of central triangular fibrocartilage tears with central perforations.

    Science.gov (United States)

    Möldner, Meike; Unglaub, Frank; Hahn, Peter; Müller, Lars P; Bruckner, Thomas; Spies, Christian K

    2015-02-01

    To investigate functional and subjective outcome parameters after arthroscopic debridement of central articular disc lesions (Palmer type 2C) and to correlate these findings with ulna length. Fifty patients (15 men; 35 women; mean age, 47 y) with Palmer type 2C lesions underwent arthroscopic debridement. Nine of these patients (3 men; 6 women; mean static ulnar variance, 2.4 mm; SD, 0.5 mm) later underwent ulnar shortening osteotomy because of persistent pain and had a mean follow-up of 36 months. Mean follow-up was 38 months for patients with debridement only (mean static ulnar variance, 0.5 mm; SD, 1.2 mm). Examination parameters included range of motion, grip and pinch strengths, pain (visual analog scale), and functional outcome scores (Modified Mayo Wrist score [MMWS] and Disabilities of the Arm, Shoulder, and Hand [DASH] questionnaire). Patients who had debridement only reached a DASH questionnaire score of 18 and an MMWS of 89 with significant pain reduction from 7.6 to 2.0 on the visual analog scale. Patients with additional ulnar shortening reached a DASH questionnaire score of 18 and an MMWS of 88, with significant pain reduction from 7.4 to 2.5. Neither surgical treatment compromised grip and pinch strength in comparison with the contralateral side. We identified 1.8 mm or more of positive ulnar variance as an indication for early ulnar shortening in the case of persistent ulnar-sided wrist pain after arthroscopic debridement. Arthroscopic debridement was a sufficient and reliable treatment option for the majority of patients with Palmer type 2C lesions. Because reliable predictors of the necessity for ulnar shortening are lacking, we recommend arthroscopic debridement as a first-line treatment for all triangular fibrocartilage 2C lesions, and, in the presence of persistent ulnar-sided wrist pain, ulnar shortening osteotomy after an interval of 6 months. Ulnar shortening proved to be sufficient and safe for these patients. Patients with persistent ulnar

  9. How does ulnar shortening osteotomy influence morphologic changes in the triangular fibrocartilage complex?

    Science.gov (United States)

    Yamanaka, Yoshiaki; Nakamura, Toshiyasu; Sato, Kazuki; Toyama, Yoshiaki

    2014-11-01

    Ulnar shortening osteotomy often is indicated for treatment of injuries to the triangular fibrocartilage complex (TFCC). However, the effect of ulnar shortening osteotomy on the changes in shape of the TFCC is unclear. In our study, quantitative evaluations were performed using MRI to clarify the effect of ulnar shortening on triangular fibrocartilage (TFC) thickness attributable to disc regeneration of the TFC and TFC angle attributable to the suspension effect of ulnar shortening on the TFC. The purposes of this study were (1) to compare preoperative and postoperative TFC thickness and TFC angle on MR images to quantitatively evaluate the effect of ulnar shortening osteotomy on disc regeneration and the suspension effect on the TFC; and (2) to assess whether changes in TFC thickness and TFC angle correlated with the Mayo wrist score. Between 1995 and 2008, 256 patients underwent ulnar shortening osteotomy for TFCC injuries. The minimum followup was 24 months (mean, 51 months; range, 24-210 months). A total of 79 patients (31%) with complete followup including preoperative and postoperative MR images and the Mayo wrist score was included in this retrospective study. Evaluation of the postoperative MR images and the Mayo wrist score were performed at the final followup. The remaining 177 patients did not undergo postoperative MRI, or they had a previous fracture, large tears of the disc proper, or were lost to followup. Two orthopaedists, one of whom performed the surgeries, measured the TFC thickness and the TFC angle on coronal MR images before and after surgery for each patient. Correlations of the percent change in the TFC thickness and the magnitude of TFC angle change with age, sex, postoperative MR images, extent of ulnar shortening, preoperative ulnar variance, and postoperative Mayo wrist score were assessed. Stepwise regression analysis showed a correlation between the percent change in TFC thickness and preoperative ulnar variance (R2=0.21; β=-0.33; 95

  10. Prevalence of triangular fibrocartilage complex abnormalities regardless of symptoms rise with age: systematic review and pooled analysis.

    Science.gov (United States)

    Chan, Jimmy J; Teunis, Teun; Ring, David

    2014-12-01

    Triangular fibrocartilage complex abnormalities seem to be more common with age, but the degree to which this is so, and the degree to which the presence of an abnormality is associated with symptoms, are topics of controversy. We wished to perform a systematic review to determine the prevalence of triangular fibrocartilage complex abnormalities, and to determine if the prevalence of abnormalities are greater with increasing age. In addition, we stratified age groups based on symptoms. We searched MEDLINE, EMBASE, and the Cochrane Library through August 15, 2013. Studies that reported triangular fibrocartilage complex abnormalities by age were included. Fifteen studies including 977 wrists met our criteria and reported a total of 368 (38%) triangular fibrocartilage complex abnormalities. Eight studies included symptomatic patients; the remainder studied cadavers (six studies) or asymptomatic volunteers (one study). Patients were divided into four age groups (fibrocartilage complex abnormalities increased with age, from 27% (80/301) in patients younger than 30 years to 49% (130/265) in patients 70 years and older (p fibrocartilage complex prevalence abnormality increased from 15% (24/159) to 49% (129/263) in the same age groups (p fibrocartilage complex abnormalities are common in symptomatic and asymptomatic wrists, and they are increasingly common with age. As in all situations where abnormalities are so common that they may be incidental, we need (1) a reliable and accurate method for determining whether these abnormalities are the cause of symptoms; and (2) evidence that treatment of these abnormalities improves symptoms better than placebo. Level III, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.

  11. Combined Palmer Type 1A and 1B Traumatic Lesions of the Triangular Fibrocartilage Complex A New Category.

    Science.gov (United States)

    Nance, Erin; Ayalon, Omri; Yang, Steven

    2016-06-01

    We present a series of eight patients who underwent wrist arthroscopy for presumed solitary tears of the triangular fibrocartilage (TFC) and were, instead, found to have combined 1A (central tear) and 1B (ulnar avulsion) tears. The Palmer Classification does not currently categorize this combined pattern. All but one patient had a traumatic injury. Each subject had preoperative radiographs and MRI scans. TFC tears were evident on all MRI scans, though only one was suggestive of a combined tear pat - tern. Surgical management included arthroscopic central tear debridement and ulnar peripheral repair. Average follow-up was 22 months. Grip strength in the affected hand improved from 16% deficit as compared to the unaffected side, to 3.5% deficit postoperatively (p = 0.003), and visual analog scores (VAS) decreased from an average of 7.1/10 preoperatively to 2.3/10 postoperatively (p < 0.001). There was no statistically significant change in wrist range of motion (ROM), however. Arthroscopic debridement of the central perforation (1A lesion) with concomitant repair of the ulnar detachment (1B lesion) resulted in functional and symptomatic improvement. This combined 1A/1B TFC injury is not reliably diagnosed preoperatively and should be considered a new subset in the Palmer classification, as this will raise awareness of its presence and assist in preoperative planning of such lesions.

  12. Patients with triangular fibrocartilage complex injuries and distal radioulnar joint instability have reduced rotational torque in the forearm.

    Science.gov (United States)

    Andersson, J K; Axelsson, P; Strömberg, J; Karlsson, J; Fridén, J

    2016-09-01

    A total of 20 patients scheduled for wrist arthroscopy, all with clinical signs of rupture to the triangular fibrocartilage complex and distal radioulnar joint instability, were tested pre-operatively by an independent observer for strength of forearm rotation. During surgery, the intra-articular pathology was documented by photography and also subsequently individually analysed by another independent hand surgeon. Arthroscopy revealed a type 1-B injury to the triangular fibrocartilage complex in 18 of 20 patients. Inter-rater reliability between the operating surgeon and the independent reviewer showed absolute agreement in all but one patient (95%) in terms of the injury to the triangular fibrocartilage complex and its classification. The average pre-operative torque strength was 71% of the strength of the non-injured contralateral side in pronation and supination. Distal radioulnar joint instability with an arthroscopically verified injury to the triangular fibrocartilage complex is associated with a significant loss of both pronation and supination torque. Case series, Level IV. © The Author(s) 2015.

  13. [Kinematics of the triangular fibrocartilage complex during forearm rotation in vivo].

    Science.gov (United States)

    Xu, Jing; Tang, Jin-bo; Jia, Zhong-zheng; Xie, Ren-guo

    2009-11-01

    To investigate three-dimensional kinematics of the superficial and deep portion of triangular fibrocartilage complex (TFCC) in different parts of the forearm rotation. Six wrists of 6 volunteers were used to obtain CT scans at different positions of the wrist. The wrists were scanned from 90 degrees of pronation to 90 degrees of supination at an interval of 30 degrees. The 3-dimensional radius and ulna were reconstructed with customized software and changes in length of the superficial and deep portion of TFCC during forearm rotation. In forearm pronation, the superficial dorsal portion and the deep palmar portion of the TFCC were tight. While the superficial palmar portion and the deep dorsal potion of the TFCC were lax. In supination, the changes in length of all these fibers were reverse. In forearm rotation one portion fibers of dorsal TFCC and one portion fibers of palmar TFCC are tight, and this mechanism controls stability during DRUJ rotation.

  14. Immunohistochemical Mapping of Sensory Nerve Endings in the Human Triangular Fibrocartilage Complex.

    Science.gov (United States)

    Rein, Susanne; Semisch, Manuel; Garcia-Elias, Marc; Lluch, Alex; Zwipp, Hans; Hagert, Elisabet

    2015-10-01

    The triangular fibrocartilage complex is the main stabilizer of the distal radioulnar joint. While static joint stability is constituted by osseous and ligamentous integrity, the dynamic aspects of joint stability chiefly concern proprioceptive control of the compressive and directional muscular forces acting on the joint. Therefore, an investigation of the pattern and types of sensory nerve endings gives more insight in dynamic distal radioulnar joint stability. We aimed to (1) analyze the general distribution of sensory nerve endings and blood vessels; (2) examine interstructural distribution of sensory nerve endings and blood vessels; (3) compare the number and types of mechanoreceptors in each part; and (4) analyze intrastructural distribution of nerve endings at different tissue depth. The subsheath of the extensor carpi ulnaris tendon sheath, the ulnocarpal meniscoid, the articular disc, the dorsal and volar radioulnar ligaments, and the ulnolunate and ulnotriquetral ligaments were dissected from 11 human cadaver wrists. Sensory nerve endings were counted in five levels per specimen as total cell amount/cm(2) after staining with low-affinity neurotrophin receptor p75, protein gene product 9.5, and S-100 protein and thereafter classified according to Freeman and Wyke. All types of sensory corpuscles were found in the various structures of the triangular fibrocartilage complex with the exception of the ulnolunate ligament, which contained only Golgi-like endings, free nerve endings, and unclassifiable corpuscles. The articular disc had only free nerve endings. Furthermore, free nerve endings were the predominant sensory nerve ending (median, 72.6/cm(2); range, 0-469.4/cm(2)) and more prevalent than all other types of mechanoreceptors: Ruffini (median, 0; range, 0-5.6/cm(2); difference of medians, 72.6; p fibrocartilage complex (p ≤ 0.001, respectively) except the ulnolunate ligament. More blood vessels were seen in the volar radioulnar ligament (median, 363

  15. MR imaging of the triangular fibrocartilage complex and intercarpal ligaments of the wrist

    International Nuclear Information System (INIS)

    Kang, H.S.; Kindynis, P.; Brahme, S.K.; Resnick, D.L.; Haghighi, P.; Haller, J.; Sartoris, D.J.

    1989-01-01

    To understand MR signal characteristics in the triangular fibrocartilage (TFC) complex, the authors performed MR imaging with gross pathologic and histologic analysis in 10 fresh cadaveric wrists. Spin-echo T1-and T2-weighted coronal images were obtained at 1.5T (10-cm field of view, 3-mm thickness, 256 x 256 matrix). Normal portions of the TFC showed a smooth surface with homogeneous low signal intensity except near the radial and lunar attachments. Mucoid degeneration of the TFC, present in all cases, was more severe on the proximal surface and was characterized by bright signal on T1-weighted and less bright signal on T2-weighted images. These findings differed from those of TFC perforation. Similar signal characteristics accompanied degeneration in the scapholunate and lunotriquetral ligaments. The author's findings indicate that MR imaging can accurately delineate degeneration as well as perforation of TFC and intercarpal ligaments

  16. The role of imaging in diagnosing diseases of the distal radioulnar joint, triangular fibrocartilage complex, and distal ulna.

    Science.gov (United States)

    Squires, Judy H; England, Eric; Mehta, Kaushal; Wissman, Robert D

    2014-07-01

    The purpose of this article is to review the anatomy, biomechanics, and multimodality imaging findings of common and uncommon distal radioulnar joint (DRUJ), triangular fibrocartilage complex, and distal ulna abnormalities. The DRUJ is a common site for acute and chronic injuries and is frequently imaged to evaluate chronic wrist pain, forearm dysfunction, and traumatic forearm injury. Given the complex anatomy of the wrist, the radiologist plays a vital role in the diagnosis of wrist pain and dysfunction.

  17. Palmar reconstruction of the triangular fibrocartilage complex for instability of the distal radioulnar joint: a biomechanical study.

    Science.gov (United States)

    Kataoka, T; Moritomo, H; Omokawa, S; Iida, A; Wada, T; Aoki, M

    2013-06-01

    We developed a new triangular fibrocartilage complex reconstruction technique for distal radioulnar joint instability in which the palmar portion of the triangular fibrocartilage complex was predominantly reconstructed, and evaluated whether such reconstruction can restore stability of the distal radioulnar joint in seven fresh cadaver upper extremities. Distal radioulnar joint instability was induced by cutting all soft-tissue stabilizers around the distal ulna. Using a palmar approach, a palmaris longus tendon graft was sutured to the remnant of the palmar radioulnar and ulnocarpal ligaments. The graft was then passed through a bone tunnel created at the fovea and was sutured. Loads were applied to the radius, and dorsopalmar displacements of the radius relative to the ulna were measured using an electromagnetic tracking device in neutral rotation, 60° supination and 60° pronation. We compared the dorsopalmar displacements before sectioning, before reconstruction and after reconstruction. Dorsopalmar instability produced by sectioning significantly improved in all forearm positions after reconstruction.

  18. High-Resolution 3T MR Imaging of the Triangular Fibrocartilage Complex.

    Science.gov (United States)

    von Borstel, Donald; Wang, Michael; Small, Kirstin; Nozaki, Taiki; Yoshioka, Hiroshi

    2017-01-10

    This study is intended as a review of 3Tesla (T) magnetic resonance (MR) imaging of the triangular fibrocartilage complex (TFCC). The recent advances in MR imaging, which includes high field strength magnets, multi-channel coils, and isotropic 3-dimensional (3D) sequences have enabled the visualization of precise TFCC anatomy with high spatial and contrast resolution. In addition to the routine wrist protocol, there are specific techniques used to optimize 3T imaging of the wrist; including driven equilibrium sequence (DRIVE), parallel imaging, and 3D imaging. The coil choice for 3T imaging of the wrist depends on a number of variables, and the proper coil design selection is critical for high-resolution wrist imaging with high signal and contrast-to-noise ratio. The TFCC is a complex structure and is composed of the articular disc (disc proper), the triangular ligament, the dorsal and volar radioulnar ligaments, the meniscus homologue, the ulnar collateral ligament (UCL), the extensor carpi ulnaris (ECU) tendon sheath, and the ulnolunate and ulnotriquetral ligaments. The Palmer classification categorizes TFCC lesions as traumatic (type 1) or degenerative (type 2). In this review article, we present clinical high-resolution MR images of normal TFCC anatomy and TFCC injuries with this classification system.

  19. Effect of Electrothermal Treatment on Nerve Tissue Within the Triangular Fibrocartilage Complex, Scapholunate, and Lunotriquetral Interosseous Ligaments.

    Science.gov (United States)

    Pirolo, Joseph M; Le, Wei; Yao, Jeffrey

    2016-05-01

    To evaluate the effect of thermal treatment on neural tissue in the triangular fibrocartilage complex (TFCC), scapholunate interosseous ligament (SLIL), and lunotriquetral interosseous ligament (LTIL). The intact TFCC, SLIL, and LTIL were harvested from cadaveric specimens and treated with a radiofrequency probe as would be performed intraoperatively. Slides were stained using a triple-stain technique for neurotrophin receptor p75, pan-neuronal marker protein gene product 9.5 (PGP 9.5), and 4',6-diamidino-2-phenylindole for neural identification. Five TFCC, 5 SLIL, and 4 LTIL specimens were imaged with fluorescence microscopy. Imaging software was used to measure fluorescence signals and compare thermally treated areas with adjacent untreated areas. A paired t test was used to compare treated versus untreated areas. P < .05 was considered significant. For the TFCC, a mean of 94.9% ± 2.7% of PGP 9.5-positive neural tissue was ablated within a mean area of 11.7 ± 2.5 mm(2) (P = .02). For the SLIL treated from the radiocarpal surface, 97.4% ± 1.0% was ablated to a mean depth of 2.4 ± 0.3 mm from the surface and a mean horizontal spread of 3.4 ± 0.5 mm (P = .01). For the LTIL, 96.0% ± 1.5% was ablated to a mean depth of 1.7 ± 0.7 mm and a mean horizontal spread of 2.6 ± 1.0 mm (P = .02). Differences in the presence of neural tissue between treated areas and adjacent untreated areas were statistically significant for all specimens. Our study confirms elimination of neuronal markers after thermal treatment of the TFCC, SLIL, and LTIL in cadaveric specimens. This effect penetrates below the surface to innervated collagen tissue that is left structurally intact after treatment. Electrothermal treatment as commonly performed to treat symptomatic SLIL, LTIL, and TFCC tears eliminates neuronal tissue in treated areas and may function to relieve pain through a denervation effect. Copyright © 2016 Arthroscopy Association of North America. Published by

  20. An immunohistochemical study of the triangular fibrocartilage complex of the wrist: regional variations in cartilage phenotype

    Science.gov (United States)

    Milz, S; Sicking, B; Sprecher, C M; Putz, R; Benjamin, M

    2007-01-01

    The triangular fibrocartilage complex (TFCC) transmits load from the wrist to the ulna and stabilizes the distal radioulnar joint. Damage to it is a major cause of wrist pain. Although its basic structure is well established, little is known of its molecular composition. We have analysed the immunohistochemical labelling pattern of the extracellular matrix of the articular disc and the meniscal homologue of the TFCC in nine elderly individuals (age range 69–96 years), using a panel of monoclonal antibodies directed against collagens, glycosaminoglycans, proteoglycans and cartilage oligomeric matrix protein (COMP). Although many of the molecules (types I, III and VI collagen, chondroitin 4 sulphate, dermatan sulphate and keratan sulphate, the oversulphated epitope of chondroitin 6 sulphate, versican and COMP) were found in all parts of the TFCC, aggrecan, link protein and type II collagen were restricted to the articular disc and to entheses. They were thus not a feature of the meniscal homologue. The shift in tissue phenotype within the TFCC, from a fibrocartilaginous articular disc to a more fibrous meniscal homologue, correlates with biomechanical data suggesting that the radial region is stiff and subject to considerable stress concentration. The presence of aggrecan, link protein and type II collagen in the articular disc could explain why the TFCC is destroyed in rheumatoid arthritis, given that it has been suggested that autoimmunity to these antigens results in the destruction of articular cartilage. The differential distribution of aggrecan within the TFCC is likely to be reflected by regional differences in water content and mobility on the radial and ulnar side. This needs to be taken into account in the design of improved MRI protocols for visualizing this ulnocarpal complex of the wrist. PMID:17532798

  1. The Traumatized TFCC: An Illustrated Review of the Anatomy and Injury Patterns of the Triangular Fibrocartilage Complex.

    Science.gov (United States)

    Skalski, Matthew R; White, Eric A; Patel, Dakshesh B; Schein, Aaron J; RiveraMelo, Hector; Matcuk, George R

    2016-01-01

    The triangular fibrocartilage complex (TFCC) plays an important role in wrist biomechanics and is prone to traumatic and degenerative injury, making it a common source of ulnar-sided wrist pain. Because of this, the TFCC is frequently imaged, and a detailed understanding of its anatomy and injury patterns is critical in generating an accurate report to help guide treatment. In this review, we provide a detailed overview of TFCC anatomy, its normal appearance on magnetic resonance imaging, the spectrum of TFCC injuries based on the Palmer classification system, and pitfalls in accurate assessment. Copyright © 2015 Mosby, Inc. All rights reserved.

  2. Arthroscopically assisted reconstruction of triangular fibrocartilage complex foveal avulsion in the ulnar variance-positive patient.

    Science.gov (United States)

    Kim, ByungSung; Yoon, Hong-Kee; Nho, Jae-Hwi; Park, Kang Hee; Park, Sung-Yong; Yoon, Jun-Hee; Song, Hyun Seok

    2013-11-01

    Our aim was to evaluate the clinical results of patients treated by arthroscopically assisted reconstruction of foveal avulsion injury of the triangular fibrocartilage complex (TFCC) using a suture anchor. We retrospectively reviewed the results of 15 patients (11 men and 4 women; mean age, 30.5 years) who underwent surgical procedures for the treatment of TFCC foveal avulsion at our hospital. The patients were followed up for a mean of 29 months. The patients had TFCC foveal avulsion caused by sprains (n = 8), falls (n = 4), playing baseball (n = 2), and a motor vehicle accident (n = 1). All the patients underwent magnetic resonance imaging. Radiographs obtained to assess ulnar variance (UV), ulnar-dorsal subluxation, and function of the wrist based on grip power; Disabilities of the Arm, Shoulder and Hand score; and Mayo wrist score were examined for all patients both preoperatively and postoperatively. On preoperative magnetic resonance imaging, TFCC foveal avulsion was observed in 13 of 15 cases. The mean UV value based on preoperative simple radiographic findings was 1.7 ± 1.0 mm, and dorsal subluxation at the distal ulna improved from 2.9 ± 3.0 mm to 0.2 ± 0.9 mm (P = .017). In all cases the distal radioulnar joint instability disappeared postoperatively. Grip power (compared with the uninvolved limb) was 79.3% preoperatively and 82.9% postoperatively (P = .086). The Disabilities of the Arm, Shoulder and Hand scores were 28.4 points preoperatively and 16.6 points postoperatively (P = .061). The Mayo wrist scores were excellent in 10 cases, good in 2, and fair in 3, and the mean score improved significantly from 64 points preoperatively to 84 points postoperatively (P = .007). Arthroscopic-assisted suture anchor reattachment of the TFCC in patients with traumatic TFCC foveal avulsion can prevent or reduce distal radioulnar joint instability and reduce pain even in chronic cases with positive UV. Level IV, therapeutic case series. Copyright © 2013

  3. Complex descemet′s membrane tears and detachment during phacoemulsification

    Directory of Open Access Journals (Sweden)

    Faik Orucoglu

    2015-01-01

    Full Text Available Purpose: To report a case of complex Descemet′s membrane detachment (DMD and tears during phacoemulsification cataract surgery. Case Report: A 64-year-old woman underwent phacoemulsification surgery in her right eye and developed tears and partial loss of Descemet′s membrane (DM while the aspiration port was inserted through the main incision. Massive corneal edema obscured the view and the anterior chamber was barely visible the following day. Scheimpflug imaging was used to complement slit lamp examination in the postoperative period. Frequent topical corticosteroid drops were initiated. After 5 days of treatment, multiple tears and detachment of DM were visible and the anterior chamber was filled with air. After 5 weeks, the cornea regained much of its clarity despite large DM tears and focal loss of DM. Conclusion: Despite partial loss of DM, the corneal edema mostly disappeared after 5 weeks of air bubble injection. Scheimpflug imaging was beneficial in the diagnosis and monitoring of DM tears and detachments.

  4. Comparison between open and arthroscopic-assisted foveal triangular fibrocartilage complex repair for post-traumatic distal radio-ulnar joint instability.

    Science.gov (United States)

    Luchetti, R; Atzei, A; Cozzolino, R; Fairplay, T; Badur, N

    2014-10-01

    The aim of this study was to assess the objective and subjective functional outcomes after foveal reattachment of proximal or complete ulnar-sided triangular fibrocartilage complex lesions by two surgical procedures: an open technique or an arthroscopically assisted repair. The study was done prospectively on 49 wrists affected by post-traumatic distal radio-ulnar joint instability. Twenty-four patients were treated with the open technique (Group 1) and 25 by the arthroscopically assisted technique (Group 2). Magnetic resonance imaging demonstrated a clear foveal detachment of the triangular fibrocartilage complex in 67% of the cases. Arthroscopy showed a positive ulnar-sided detachment of the triangular fibrocartilage complex (positive hook test) in all cases. Distal radio-ulnar joint stability was obtained in all but five patients at a mean follow-up of 6 months. Both groups had improvement of all parameters with significant differences in wrist pain scores, Mayo wrist score, Disability of the Arm, Shoulder and Hand questionnaire and Patient-Rated Wrist/Hand Evaluation questionnaire scores. There were no significant post-operative differences between the two groups in the outcome parameters except for the Disability of the Arm Shoulder and Hand questionnaire score, which was significantly better in Group 2 (p < 0.001). © The Author(s) 2013.

  5. Proximity of the Triangular Fibrocartilage Complex to Key Surrounding Structures and Safety Assessment of an Arthroscopic Repair Technique: A Cadaveric Study.

    Science.gov (United States)

    Kuremsky, Marshall A; Habet, Nahir; Peindl, Richard D; Gaston, R Glenn

    2016-12-01

    To quantify the distance of the dorsal ulnar sensory branch, floor of the extensor carpi ulnaris (ECU) subsheath, and ulnar neurovascular bundles from the triangular fibrocartilage complex (TFCC), and secondarily to assess the safety of an all-inside arthroscopic repair of the TFCC with a commonly used meniscal repair device with respect to the aforementioned structures. A custom K-wire with 1-mm gradation was used to determine the distance of at-risk structures from the periphery of the TFCC in 13 above-elbow human cadaver specimens. An all-inside repair of the TFCC at the location of a Palmer 1B tear was then performed using a commonly employed meniscal repair device. The distance from the deployed devices to the structure in closest proximity was then measured using digital calipers. The mean distance from the deployed device to the nearest structure of concern for iatrogenic injury was 9.4 mm (range, 5-15 mm). The closest structure to iatrogenic injury was usually, but not always, the dorsal ulnar sensory nerve in 9 of 13 wrists (69.2%) at 9.3 mm (range, 5-15 mm); on 3 occasions it was instead the ulnar nerve (23.1%) at 9.5 mm (range, 9-10 mm), and on 1 occasion 6 mm from the flexor digitorum profundus to the little finger (7.7%). Forearm rotation had no significant effect on measured distances (ulnar nerve: P = .98; dorsal sensory: P = .89; ECU: P = .90). The largest influence of forearm rotation was a 0.4-mm difference between pronation and supination with respect to the distance of the TFCC periphery on the ECU subsheath. An all-inside arthroscopic TFCC repair using a commonly used meniscal repair device appears safe with respect to nearby neurovascular structures and tendons under typical arthroscopic conditions. An all-inside arthroscopic TFCC repair using a commonly employed meniscal repair device appears safe in terms of proximity to important structures although further clinical investigation is warranted. Copyright © 2016 Arthroscopy

  6. High-resolution MR imaging of triangular fibrocartilage complex (TFCC): comparison of microscopy coils and a conventional small surface coil

    Energy Technology Data Exchange (ETDEWEB)

    Yoshioka, Hiroshi [Department of Radiology, University of Tsukuba, Tsukuba (Japan); Department of Radiology, Brigham and Women' s Hospital, 75 Francis Street, 02115, Boston, MA (United States); Ueno, Teruko; Itai, Yuji [Department of Radiology, University of Tsukuba, Tsukuba (Japan); Tanaka, Toshikazu [Department of Orthopedic Surgery, Tsukuba Kinen Hospital, Tsukuba (Japan); Shindo, Masashi [Tsukuba University Hospital, Tsukuba (Japan)

    2003-10-01

    To compare MR images of the triangular fibrocartilage complex (TFCC) using microscopy coils with those using a conventional surface coil qualitatively and quantitatively. Proton density-weighted images and T2*-weighted images of the TFCC from ten normal volunteers were obtained with a conventional surface coil (C4 coil; 80 mm in diameter), a 47-mm microscopy surface coil and a 23-mm microscopy surface coil at 1.5 T. Qualitative image analysis of MR images with three coils was performed by two radiologists who assigned one of five numerical scores (0, nonvisualization; 1, poor; 2, average; 3, good; 4, excellent) for five TFCC components, which were disc proper, triangular ligament, meniscus homologue, ulnotriquetral and ulnolunate ligament. Quantitative analysis included the signal-to-noise ratio (S/N) of the disc proper of TFCC, the lunate cartilage, the lunate bone and the contrast-noise-ratio (C/N) between articular cartilage and disc proper or bone marrow were measured. All structures show higher scores qualitatively on MR with microscopy coils than those with a C4 coil, and the difference was significant with the exception of the ulnolunate ligament. MR with microscopy coils showed significantly higher S/N values than those with a conventional surface coil (P<0.05 to P<0.001). T2*-weighted images using microscopy coils showed significantly higher cartilage-disc proper C/N and cartilage-bone marrow C/N (P<0.01 to P<0.001). On proton density-weighted images, the C/N between cartilage and disc proper with two microscopy coils was significantly higher (P<0.01) than that with a conventional coil. High-resolution MR images of the normal wrist using microscopy coils were superior to those using a conventional surface coil qualitatively and quantitatively. High-resolution MR imaging with a microscopy coil would be a promising method to diagnose TFCC lesions. (orig.)

  7. Comparison of arthoroscopic findings and high-resolution MRI using a microscopy coil findings for triangle fibrocartilage complex injury

    International Nuclear Information System (INIS)

    Satomi, Yoshiaki; Shimizu, Hiroyuki; Arai, Takeshi; Izumiyama, Kou; Beppu, Moroe

    2008-01-01

    Triangle fibrocartilage complex (TFCC) is very small and can be visualized in MRI. We compared image findings acquired by high-resolution MRI using a 47-mm-diameter microscopy coil with arthroscopic findings and reviewed the availability and possibility of application of both these techniques. The subjects were 16 patients who underwent arthroscopy of the radiocarpal joint and MRI for the diagnosis of pain in the ulnar wrist joint. Based on image evaluation, the impaired site was categorized as follows radius attachment, disc proper, triangular ligament (upper lamina), triangular ligament (lower lamina), lunate bone cartilage face, and triquete bone cartilage face; the findings of both techniques for impaired site around part 6 were compared. Joint morphology was assessed by the gradient-recalled echo (GRE) method with T2-weighted images, and the cartilage side was analyzed the fast SE (FSE) method with proton density-weighted image. Three orthopedic surgeons and 1 radiologist interpreted the results. The impaired site was verified in all 16 patients by high-resolution MRI using a microscopy coil. The MRI findings were as follows radius attachment in 2 patients, disc proper in 4, upper lamina in 7, lower lamina in 5, lunate bone cartilage face in 3, and triquete bone cartilage face in 0. The frequency of injury according to arthroscopic findings was as follows: radius attachment in 2 patients, disc proper in 4, lunate bone cartilage face in 6, and triquete bone cartilage face in 0. The sensibility/specificity of arthroscopic findings in comparison with MRI findings was as follows: radius attachment 100%/100%, disc proper 75%/91.7%, lunate bone cartilage face 50%/100%, and triquete bone cartilage face 0%/100%. Eight of 16 patients had depression of TFCC tone, and the sensibility/specificity of arthroscopic findings in comparison with MRI findings for the depression of site and TFCC tone was as follows: upper lamina 75%/87.5% and lower lamina 50%/87.5%. High

  8. High-resolution 3T Magnetic Resonance Imaging of the Triangular Fibrocartilage Complex in Chinese Wrists: Correlation with Cross-sectional Anatomy.

    Science.gov (United States)

    Zhan, Hui-Li; Li, Wen-Ting; Bai, Rong-Jie; Wang, Nai-Li; Qian, Zhan-Hua; Ye, Wei; Yin, Yu-Ming

    2017-04-05

    The injury of the triangular fibrocartilage complex (TFCC) is a common cause of ulnar-sided wrist pain. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) could demonstrate the detailed complex anatomy of TFCC in Chinese. Fourteen Chinese cadaveric wrists (from four men and three women; age range at death from 30 to 60 years; mean age at 46 years) and forty healthy Chinese wrists (from 20 healthy volunteers, male/female: 10/10; age range from 21 to 53 years with a mean age of 32 years) in Beijing Jishuitan Hospital from March 2014 to March 2016 were included in this study. All cadavers and volunteers had magnetic resonance (MR) examination of the wrist with coronal T1-weighted and proton density-weighted imaging with fat suppression in three planes, respectively. MR arthrography (MRAr) was performed on one of the cadaveric wrists. Subsequently, all 14 cadaveric wrists were sliced into 2 mm thick slab with band saw (six in coronal plane, four in sagittal plane, and four in axial plane). The MRI features of normal TFCC were analyzed in these specimens and forty healthy wrists. Triangular fibrocartilage, the ulnar collateral ligament, and the meniscal homolog could be best observed on images in coronal plane. The palmar and dorsal radioulnar ligaments were best evaluated in transverse plane. The ulnotriquetral and ulnolunate ligaments were best visualized in sagittal plane. The latter two structures and the volar and dorsal capsules were better demonstrated on MRAr. High-resolution 3T MRI is capable to show the detailed complex anatomy of the TFCC and can provide valuable information for the clinical diagnosis in Chinese.

  9. Patterns of triangular fibrocartilage complex (TFCC) injury associated with severely dorsally displaced extra-articular distal radius fractures.

    Science.gov (United States)

    Scheer, Johan H; Adolfsson, Lars E

    2012-06-01

    The aim of the study was to examine triangular fibrocartilage (TFCC) injury patterns associated with unstable, extra-articular dorsally displaced distal radius fractures. Twenty adult patients with an Arbeitsgemeinschaft für Osteosynthesefragen (AO), type A2 or A3, distal radius fracture with an initial dorsal angulation greater than 20° were included. Nine had a tip fracture (distal to the base) of the ulnar styloid and 11 had no such fracture. They were all openly explored from an ulnopalmar approach and TFCC injuries were documented. Eleven patients also underwent arthroscopy and intra-articular pathology was recorded. All patients had TFCC lesions of varying severity, having an extensor carpi ulnaris subsheath avulsion in common. Eighteen out of 20 also displayed deep foveal radioulnar ligament lesions, with decreasingly dorsal fibres remaining. The extent of this foveal injury could not be appreciated by radiocarpal arthroscopy. Severe displacement of an extra-articular radius fracture suggests an ulnar-sided ligament injury to the TFCC. The observed lesions concur with findings in a previous cadaver study. The lesions follow a distinct pattern affecting both radioulnar as well as ulnocarpal stabilisers. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Can the Diagnostics of Triangular Fibrocartilage Complex Lesions Be Improved by MRI-Based Soft-Tissue Reconstruction? An Imaging-Based Workup and Case Presentation.

    Science.gov (United States)

    Hammer, Niels; Hirschfeld, Ulrich; Strunz, Hendrik; Werner, Michael; Wolfskämpf, Thomas; Löffler, Sabine

    2017-01-01

    Introduction . The triangular fibrocartilage complex (TFCC) provides both mobility and stability of the radiocarpal joint. TFCC lesions are difficult to diagnose due to the complex anatomy. The standard treatment for TFCC lesions is arthroscopy, posing surgery-related risks onto the patients. This feasibility study aimed at developing a workup for soft-tissue reconstruction using clinical imaging, to verify these results in retrospective patient data. Methods . Microcomputed tomography ( μ -CT), 3 T magnetic resonance imaging (MRI), and plastination were used to visualize the TFCC in cadaveric specimens applying segmentation-based 3D reconstruction. This approach further trialed the MRI dataset of a patient with minor radiological TFCC alterations but persistent pain. Results . TFCC reconstruction was impossible using μ -CT only but feasible using MRI, resulting in an appreciation of its substructures, as seen in the plastinates. Applying this approach allowed for visualizing a Palmer 2C lesion in a patient, confirming ex postum the arthroscopy findings, being markedly different from MRI (Palmer 1B). Discussion . This preliminary study showed that image-based TFCC reconstruction may help to identify pathologies invisible in standard MRI. The combined approach of μ -CT, MRI, and plastination allowed for a three-dimensional appreciation of the TFCC. Image quality and time expenditure limit the approach's usefulness as a diagnostic tool.

  11. Can the Diagnostics of Triangular Fibrocartilage Complex Lesions Be Improved by MRI-Based Soft-Tissue Reconstruction? An Imaging-Based Workup and Case Presentation

    Directory of Open Access Journals (Sweden)

    Niels Hammer

    2017-01-01

    Full Text Available Introduction. The triangular fibrocartilage complex (TFCC provides both mobility and stability of the radiocarpal joint. TFCC lesions are difficult to diagnose due to the complex anatomy. The standard treatment for TFCC lesions is arthroscopy, posing surgery-related risks onto the patients. This feasibility study aimed at developing a workup for soft-tissue reconstruction using clinical imaging, to verify these results in retrospective patient data. Methods. Microcomputed tomography (μ-CT, 3 T magnetic resonance imaging (MRI, and plastination were used to visualize the TFCC in cadaveric specimens applying segmentation-based 3D reconstruction. This approach further trialed the MRI dataset of a patient with minor radiological TFCC alterations but persistent pain. Results. TFCC reconstruction was impossible using μ-CT only but feasible using MRI, resulting in an appreciation of its substructures, as seen in the plastinates. Applying this approach allowed for visualizing a Palmer 2C lesion in a patient, confirming ex postum the arthroscopy findings, being markedly different from MRI (Palmer 1B. Discussion. This preliminary study showed that image-based TFCC reconstruction may help to identify pathologies invisible in standard MRI. The combined approach of μ-CT, MRI, and plastination allowed for a three-dimensional appreciation of the TFCC. Image quality and time expenditure limit the approach’s usefulness as a diagnostic tool.

  12. A Comparison of Ulnar Shortening Osteotomy Alone Versus Combined Arthroscopic Triangular Fibrocartilage Complex Debridement and Ulnar Shortening Osteotomy for Ulnar Impaction Syndrome

    Science.gov (United States)

    Song, Hyun Seok

    2011-01-01

    Background This study compared the results of patients treated for ulnar impaction syndrome using an ulnar shortening osteotomy (USO) alone with those treated with combined arthroscopic debridement and USO. Methods The results of 27 wrists were reviewed retrospectively. They were divided into three groups: group A (USO alone, 10 cases), group B (combined arthroscopic debridement and USO, 9 cases), and group C (arthroscopic triangular fibrocartilage complex [TFCC] debridement alone, 8 cases). The wrist function was evaluated using the modified Mayo wrist score, disabilities of the arm, shoulder and hand (DASH) score and Chun and Palmer grading system. Results The modified Mayo wrist score in groups A, B, and C was 74.5 ± 8.9, 73.9 ± 11.6, and 61.3 ± 10.2, respectively (p 0.05). Conclusions Both USO alone and combined arthroscopic TFCC debridement with USO improved the wrist function and reduced the level of pain in the patients treated for ulnar impaction syndrome. USO alone may be the preferred method of treatment in patients if the torn flap of TFCC is not unstable. PMID:21909465

  13. MR imaging of the triangular fibrocartilage of the wrist

    International Nuclear Information System (INIS)

    Golimbu, C.N.; Firooznia, H.; Rafii, M.; Melone, C.; Leber, C.

    1988-01-01

    Magnetic resonance (MR) imaging of the wrist was performed in 25 patients who had pain or localized soft-tissue swelling in the ulnar side of the wrist. T1-weighted coronal images were obtained in all patients. In addition, coronal or axial images with T2-weighted or fast-field-echo sequences were obtained in 16 of these patients. MR imaging demonstrated tears of the triangular fibrocartilage of the wrist in 13 patients. Twelve of these tears were confirmed at surgery. In one patient, the triangular fibrocartilage was found at surgery to be stretched and folded on itself but not torn. This represents the one false-positive MR image in this group of patients. In 12 patients, the symptoms could be explained by a diversity of MR abnormalities, such as aseptic necrosis of carpal bones, subluxation of distal radioulnar joint, and synovitis of the tendon sheaths. MR imaging offers the advantage of investigating the triangular fibrocartilage of the wrist in a noninvasive manner; it may be used as a screening method in patients considered for surgery

  14. A study of complex defects failing by fatigue, ductile tearing and cleavage

    International Nuclear Information System (INIS)

    Bezensek, B.; Ren, Z.; Hancock, J.W.

    2001-01-01

    Defect assessment procedures ensure the structural integrity of plant, which may contain complex defects. The present work addresses complex defects with re-entrant sectors, which develop from the interaction of two co-planar surface breaking defects in fatigue. Experimental studies show rapid fatigue growth and amplified crack driving forces in the re-entrant sector. This leads to the rapid evolution of the complex crack into a bounding semielliptical defect. Experiments involving ductile tearing of cracks with a re-entrant sector show that tearing initiates in the re-entrant sector and that the defect evolves into a bounding semielliptical defect. Cleavage failures of defects with re-entrant sectors indicate the re-characterisation procedure is only conservative after invoking constraint arguments. The study confirms the conservatism inherent in the re-characterisation rules of assessment procedures, such as BS 7910 [1] and ASME Section XI [2] for complex defects extending by fatigue or ductile tearing. A potentially non-conservative situation exists for defects with re-entrant sectors failing by cleavage at small fractions of the limit load.(author)

  15. What happens to the triangular fibrocartilage complex during pronation and supination of the forearm? Analysis of its morphology and diagnostic assessment with MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Pfirrmann, C.W.A. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Dept. of Radiology, Orthopedic University Hospital Balgrist, Zurich (Switzerland); Theumann, N.H. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Service de Radiologie, CHUV, Lausanne (Switzerland); Chung, C.B.; Trudell, D.J.; Resnick, D. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Botte, M.J. [Div. of Orthopedic Surgery, Scripps Clinic and Research Foundation, La Jolla, CA (United States)

    2001-12-01

    Objective: To evaluate the dynamic morphologic changes of the triangular fibrocartilage complex (TFCC) during pronation and supination of the forearm using high-resolution MR arthrography in cadavers and to evaluate the impact of these changes on the diagnostic assessment of the normal and abnormal TFCC. Design and specimens: High-resolution MR arthrography of 10 wrists of cadaveric specimens was obtained in maximum pronation, in the neutral position, and in maximum supination of the forearm. The structures of the TFCC were evaluated by two musculoskeletal radiologists and correlated with anatomic sections. The position of the forearm that allowed the best visualization of normal structures and lesions of the TFCC was determined. Results: The shape and extent of the articular disc as well as the radial portions of the radioulnar ligaments did not change with pronation and supination. The articular disc was horizontal in the neutral position and tilted more distally to align with the proximal carpal row in pronation and supination. The fibers of the ulnar part of the radioulnar ligaments (ulnar attachment of the articular disc) revealed the most significant changes: their orientation was coronal in the neutral position and sagittal in positions of pronation and supination. The ulnomeniscal homologue was largest in the neutral position and was reduced in size during pronation and supination. The extensor carpi ulnaris tendon was centered in its groove in the neutral position and pronation. In supination this tendon revealed subluxation from this groove. The dorsal capsule of the distal radioulnar joint was taut in pronation, and the palmar capsule was taut in supination. The preferred forearm position for analysis of most of the structures of the TFCC was the neutral position, followed by the pronated position. The neutral position was rated best for the detection of ulnar and radial detachments of the TFCC, followed by the pronated position, except for two central

  16. Complex Medial Meniscus Tears Are Associated With a Biconcave Medial Tibial Plateau.

    Science.gov (United States)

    Barber, F Alan; Getelman, Mark H; Berry, Kathy L

    2017-04-01

    To determine whether an association exists between a biconcave medial tibial plateau and complex medial meniscus tears. A consecutive series of stable knees undergoing arthroscopy were evaluated retrospectively with the use of preoperative magnetic resonance imaging (MRI), radiographs, and arthroscopy documented by intraoperative videos. Investigators independently performed blinded reviews of the MRI or videos. Based on the arthroscopy findings, medial tibial plateaus were classified as either biconcave or not biconcave. A transverse coronal plane ridge, separating the front of the tibial plateau from the back near the inner margin of the posterior body of the medial meniscus, was defined as biconcave. The medial plateau slope was calculated with MRI sagittal views. General demographic information, body mass index, and arthroscopically confirmed knee pathology were recorded. A total of 179 consecutive knees were studied from July 2014 through August 2015; 49 (27.2%) biconcave medial tibial plateaus and 130 (72.8%) controls were identified at arthroscopy. Complex medial meniscus tears were found in 103. Patients with a biconcave medial tibial plateau were found to have more complex medial meniscus tears (69.4%) than those without a biconcavity (53.1%) (P = .049) despite having lower body mass index (P = .020). No difference in medial tibial plateau slope was observed for biconcavities involving both cartilage and bone, bone only, or an indeterminate group (P = .47). Biconcave medial tibial plateaus were present in 27.4% of a consecutive series of patients undergoing knee arthroscopy. A biconcave medial tibial plateau was more frequently associated with a complex medial meniscus tear. Level III, case-control study. Copyright © 2016 Arthroscopy Association of North America. All rights reserved.

  17. High-resolution 3 T MRI of traumatic and degenerative triangular fibrocartilage complex (TFCC) abnormalities using Palmer and Outerbridge classifications.

    Science.gov (United States)

    Nozaki, T; Rafijah, G; Yang, L; Ueno, T; Horiuchi, S; Hitt, D; Yoshioka, H

    2017-10-01

    To investigate the usefulness of high-resolution 3 T magnetic resonance imaging (MRI) for the evaluation of traumatic and degenerative triangular fibrocartilage complex (TFCC) abnormalities among three groups: patients presenting with wrist pain who were (a) younger than age 50 years or (b) age 50 or older (PT<50 and PT≥50, respectively), and (c) asymptomatic controls who were younger than age 50 years (AC). High-resolution 3 T MRI was evaluated retrospectively in 96 patients, including 47 PT<50, 38 PT≥50, and 11 AC. Two board-certified radiologists reviewed the MRI images independently. MRI features of TFCC injury were analysed according to the Palmer classification, and cartilage degeneration around the TFCC was evaluated using the Outerbridge classification. Differences in MRI findings among these groups were detected using chi-square test. Cohen's kappa was calculated to assess interobserver and intra-observer reliability. The incidence of Palmer class 1A, 1C and 1D traumatic TFCC injury was significantly (p<0.05) higher in PT≥50 than in PT<50 (class 1A: 47.4% versus 27.7%, class 1C: 31.6% versus 12.8%, and class 1D: 21.1% versus 2.1%). Likewise, MRI findings of TFCC degeneration were observed more frequently in PT≥50 than in PT<50 (p<0.01). Outerbridge grade 2 or higher cartilage degeneration was significantly (p<0.01) more frequently seen in PT≥50 than in PT<50 (55.3% versus 17% in the lunate, 28.9% versus 4.3% in the triquetrum, 73.7% versus 12.8% in the ulna). High-resolution wrist MRI at 3 T enables detailed evaluation of TFCC traumatic injury and degenerative changes using the Palmer and Outerbridge classifications, with good or excellent interobserver and intra-observer reliability. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  18. Diagnosing central lesions of the triangular fibrocartilage as traumatic or degenerative: a review of clinical accuracy.

    Science.gov (United States)

    Löw, S; Erne, H; Pillukat, T; Mühldorfer-Fodor, M; Unglaub, F; Spies, C K

    2017-05-01

    This study examined the reliability of surgeons' estimations as to whether central lesions of the triangular fibrocartilage complex were traumatic or degenerative. A total of 50 consecutive central triangular fibrocartilage complex lesions were independently rated by ten experienced wrist surgeons viewing high-quality arthroscopy videos. The videos were reassessed after intervals of 3 months; at the second assessment surgeons were given the patient's history, radiographs and both, each in a randomized order. Finally, the surgeons assessed the histories and radiographs without the videos. Kappa statistics revealed fair interrater agreement when the histories were added to the videos. The other four modalities demonstrated moderate agreement, with lower Kappa values for the assessment without videos. Intra-rater reliability showed fair agreement for three surgeons, moderate agreement for two surgeons and substantial agreement for five surgeons. It appears that classification of central triangular fibrocartilage complex lesions depends on the information provided upon viewing the triangular fibrocartilage complex at arthroscopy. II.

  19. Comparison of conventional MRI and MR arthrography in the evaluation of wrist ligament tears: A preliminary experience

    Science.gov (United States)

    Pahwa, Shivani; Srivastava, Deep N; Sharma, Raju; Gamanagatti, Shivanand; Kotwal, Prakash P; Sharma, Vijay

    2014-01-01

    Aims: To compare conventional magnetic resonance imaging (MRI) and direct magnetic resonance (MR) arthrography in the evaluation of triangular fibrocartilage complex (TFCC) and intrinsic wrist ligament tears. Materials and Methods: T1-weighted, fat suppressed (FS) proton density plus T2-weighted (FS PD/T2), 3D multiple-echo data image combination (MEDIC) sequences and direct MR arthrography were performed in 53 patients with wrist pain. Images were evaluated for the presence and location of TFCC, scapholunate ligament (SLL) and lunatotriquetral ligament (LTL) tears, and imaging findings were compared with operative findings in 16 patients who underwent arthroscopy or open surgery (gold standard). Results: Sixteen patients underwent arthroscopy/open surgery: 12 TFCC tears were detected arthroscopically out of which 9 were detected on FS PD/T2 sequence, 10 on MEDIC sequence, and all 12 were detected on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in the detection of TFCC tears were 75%, 83.3%, and 100%, respectively. Out of the eight arthroscopically confirmed SLL tears, three tears were detected on FS PD/T2 sequence, five on MEDIC sequence, and all eight were visualized on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in detecting SLL tears were 37.5%, 62.5%, and 100%, respectively. One arthroscopically confirmed LTL tear was diagnosed on FS PD/T2 sequence, three on MEDIC sequence, and all five arthroscopically confirmed LTL tears were detected with MR arthrography. The sensitivities of PD, MEDIC sequences, and MR arthrography in detecting LTL tears were 20%, 40%, and 100%, respectively. Conclusions: MR arthrography is the most sensitive and specific imaging modality for the evaluation of wrist ligament tears. PMID:25114389

  20. Comparison of conventional MRI and MR arthrography in the evaluation of wrist ligament tears: A preliminary experience

    Directory of Open Access Journals (Sweden)

    Shivani Pahwa

    2014-01-01

    Full Text Available Aims: To compare conventional magnetic resonance imaging (MRI and direct magnetic resonance (MR arthrography in the evaluation of triangular fibrocartilage complex (TFCC and intrinsic wrist ligament tears. Materials and Methods: T1-weighted, fat suppressed (FS proton density plus T2-weighted (FS PD/T2, 3D multiple-echo data image combination (MEDIC sequences and direct MR arthrography were performed in 53 patients with wrist pain. Images were evaluated for the presence and location of TFCC, scapholunate ligament (SLL and lunatotriquetral ligament (LTL tears, and imaging findings were compared with operative findings in 16 patients who underwent arthroscopy or open surgery (gold standard. Results: Sixteen patients underwent arthroscopy/open surgery: 12 TFCC tears were detected arthroscopically out of which 9 were detected on FS PD/T2 sequence, 10 on MEDIC sequence, and all 12 were detected on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in the detection of TFCC tears were 75%, 83.3%, and 100%, respectively. Out of the eight arthroscopically confirmed SLL tears, three tears were detected on FS PD/T2 sequence, five on MEDIC sequence, and all eight were visualized on MR arthrography. The sensitivities of FS PD/T2, MEDIC sequences, and MR arthrography in detecting SLL tears were 37.5%, 62.5%, and 100%, respectively. One arthroscopically confirmed LTL tear was diagnosed on FS PD/T2 sequence, three on MEDIC sequence, and all five arthroscopically confirmed LTL tears were detected with MR arthrography. The sensitivities of PD, MEDIC sequences, and MR arthrography in detecting LTL tears were 20%, 40%, and 100%, respectively. Conclusions: MR arthrography is the most sensitive and specific imaging modality for the evaluation of wrist ligament tears.

  1. Characterization of calcium and zinc spatial distributions at the fibrocartilage zone of bone-tendon junction by synchrotron radiation-based micro X-ray fluorescence analysis combined with backscattered electron imaging

    Science.gov (United States)

    Lu, Hongbin; Chen, Can; Wang, Zhanwen; Qu, Jin; Xu, Daqi; Wu, Tianding; Cao, Yong; Zhou, Jingyong; Zheng, Cheng; Hu, Jianzhong

    2015-09-01

    Tendon attaches to bone through a functionally graded fibrocartilage zone, including uncalcified fibrocartilage (UF), tidemark (TM) and calcified fibrocartilage (CF). This transition zone plays a pivotal role in relaxing load transfer between tendon and bone, and serves as a boundary between otherwise structurally and functionally distinct tissue types. Calcium and zinc are believed to play important roles in the normal growth, mineralization, and repair of the fibrocartilage zone of bone-tendon junction (BTJ). However, spatial distributions of calcium and zinc at the fibrocartilage zone of BTJ and their distribution-function relationship are not totally understood. Thus, synchrotron radiation-based micro X-ray fluorescence analysis (SR-μXRF) in combination with backscattered electron imaging (BEI) was employed to characterize the distributions of calcium and zinc at the fibrocartilage zone of rabbit patella-patellar tendon complex (PPTC). For the first time, the unique distributions of calcium and zinc at the fibrocartilage zone of the PPTC were clearly mapped by this method. The distributions of calcium and zinc at the fibrocartilage zone of the PPTC were inhomogeneous. A significant accumulation of zinc was exhibited in the transition region between UF and CF. The highest zinc content (3.17 times of that of patellar tendon) was found in the TM of fibrocartilage zone. The calcium content began to increase near the TM and increased exponentially across the calcified fibrocartilage region towards the patella. The highest calcium content (43.14 times of that of patellar tendon) was in the transitional zone of calcified fibrocartilage region and the patella, approximately 69 μm from the location with the highest zinc content. This study indicated, for the first time, that there is a differential distribution of calcium and zinc at the fibrocartilage zone of PPTC. These observations reveal new insights into region-dependent changes across the fibrocartilage zone of

  2. Application of tearing instability analysis for complex crack geometries in nuclear piping

    International Nuclear Information System (INIS)

    Pan, J.; Wilkowski, G.

    1984-01-01

    The analysis of the experimental data of 304 stainless steel pipes using Zahoor and Kanninen's estimation scheme has shown that the J resistance curve of a circumferentially cracked pipe with a simulated internal surface crack around the remaining net section is much lower than the J resistance curve of pipes with a idealized through-wall crack (without a simulated internal surface crack). The implications of the low J at initiation and tearing modulus on the stability analysis of typical BWR piping systems are discussed on the condition that an internal circumferential surface crack is assumed to occur along with a circumferential through-wall crack due to stress corrosion. The results presented here show that the margin of safety is reduced and in some cases instability is predicted due to the low J resistance curve and tearing modulus

  3. Comparison of shoulder positions at MR arthrography: change of labroligamentous complex shape and diagnosis of labral tears

    International Nuclear Information System (INIS)

    Kwak, Jin Young; Ha, Doo Hoe; Kim, Jeung Sook; Lee, Young Soo

    2001-01-01

    To compare the neutral, internal, and external rotation positions of the glenohumeral joint during magnetic resonance (MR) arthrography performed to assess changes in the shape of the labroligamentous complex (LLC) and in the labral tear. MR arthrography of the shoulder was retrospectively evaluated in 36 patients aged 14-66 (mean, 40) years. Fourteen cases were confirmed by arthroscopic surgery (7 SLAP lesions, 2 Bankart lesions, 1 both SLAP and Bankart lesions). Axial fat-suppressed T1-weighted spin-echo images were acquired with each shoulder in the neutral position, and with internal and external rotations. In each position, we measured the angle of rotation between the perpendicular line on the glenoid fossa and the long axis of the humeral head, analyzing the relationship between the rotational angle and changes in the shape of the LLC at each internal and external rotation, relative to the neutral position. In addition, labral tears in 14 arthroscopically confirmed joints were evaluated in each position. Mean angles of rotation relative to the neutral position were 44.1 and 45.3 degrees in internal and external rotation, respectively. Changes in the anterior LLC occurred in 25 and 24 cases of internal and external rotation, respectively. There was a significantly meaningful relationship between rotational angle and changes in the shape of the anterior LLC during external rotation, and when this changes was noticed, the rotational angle was wider (p<0.05). The posterior LLC changed in shape in 13 and 16 cases of internal and external rotation, respectively, but changes according to the angle of rotation were not statistically significant. In arthroscopically confirmed joints, diagnosis of the eight SLAP lesions at external rotation tended to become more accurate, but no statistically significant differences were noted (p=0.07). Two Bankart lesions were interpreted as a tear in all three positions, and one other such lesion was interpreted as a tear in the

  4. Engineering functional anisotropy in fibrocartilage neotissues.

    Science.gov (United States)

    MacBarb, Regina F; Chen, Alison L; Hu, Jerry C; Athanasiou, Kyriacos A

    2013-12-01

    The knee meniscus, intervertebral disc, and temporomandibular joint (TMJ) disc all possess complex geometric shapes and anisotropic matrix organization. While these characteristics are imperative for proper tissue function, they are seldom recapitulated following injury or disease. Thus, this study's objective was to engineer fibrocartilages that capture both gross and molecular structural features of native tissues. Self-assembled TMJ discs were selected as the model system, as the disc exhibits a unique biconcave shape and functional anisotropy. To drive anisotropy, 50:50 co-cultures of meniscus cells and articular chondrocytes were grown in biconcave, TMJ-shaped molds and treated with two exogenous stimuli: biomechanical (BM) stimulation via passive axial compression and bioactive agent (BA) stimulation via chondroitinase-ABC and transforming growth factor-β1. BM + BA synergistically increased Col/WW, Young's modulus, and ultimate tensile strength 5.8-fold, 14.7-fold, and 13.8-fold that of controls, respectively; it also promoted collagen fibril alignment akin to native tissue. Finite element analysis found BM stimulation to create direction-dependent strains within the neotissue, suggesting shape plays an essential role toward driving in vitro anisotropic neotissue development. Methods used in this study offer insight on the ability to achieve physiologic anisotropy in biomaterials through the strategic application of spatial, biomechanical, and biochemical cues. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Characterization of calcium and zinc spatial distributions at the fibrocartilage zone of bone–tendon junction by synchrotron radiation-based micro X-ray fluorescence analysis combined with backscattered electron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Hongbin; Chen, Can; Wang, Zhanwen; Qu, Jin; Xu, Daqi [Department of Sports Medicine, Research Center of Sports Medicine, Xiangya Hospital, Central South University, Changsha 410008 (China); Wu, Tianding; Cao, Yong [Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008 (China); Zhou, Jingyong; Zheng, Cheng [Department of Sports Medicine, Research Center of Sports Medicine, Xiangya Hospital, Central South University, Changsha 410008 (China); Hu, Jianzhong, E-mail: jianzhonghu@hotmail.com [Department of Sports Medicine, Research Center of Sports Medicine, Xiangya Hospital, Central South University, Changsha 410008 (China); Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha 410008 (China)

    2015-09-01

    Tendon attaches to bone through a functionally graded fibrocartilage zone, including uncalcified fibrocartilage (UF), tidemark (TM) and calcified fibrocartilage (CF). This transition zone plays a pivotal role in relaxing load transfer between tendon and bone, and serves as a boundary between otherwise structurally and functionally distinct tissue types. Calcium and zinc are believed to play important roles in the normal growth, mineralization, and repair of the fibrocartilage zone of bone–tendon junction (BTJ). However, spatial distributions of calcium and zinc at the fibrocartilage zone of BTJ and their distribution–function relationship are not totally understood. Thus, synchrotron radiation-based micro X-ray fluorescence analysis (SR-μXRF) in combination with backscattered electron imaging (BEI) was employed to characterize the distributions of calcium and zinc at the fibrocartilage zone of rabbit patella–patellar tendon complex (PPTC). For the first time, the unique distributions of calcium and zinc at the fibrocartilage zone of the PPTC were clearly mapped by this method. The distributions of calcium and zinc at the fibrocartilage zone of the PPTC were inhomogeneous. A significant accumulation of zinc was exhibited in the transition region between UF and CF. The highest zinc content (3.17 times of that of patellar tendon) was found in the TM of fibrocartilage zone. The calcium content began to increase near the TM and increased exponentially across the calcified fibrocartilage region towards the patella. The highest calcium content (43.14 times of that of patellar tendon) was in the transitional zone of calcified fibrocartilage region and the patella, approximately 69 μm from the location with the highest zinc content. This study indicated, for the first time, that there is a differential distribution of calcium and zinc at the fibrocartilage zone of PPTC. These observations reveal new insights into region-dependent changes across the fibrocartilage

  6. Characterization of calcium and zinc spatial distributions at the fibrocartilage zone of bone–tendon junction by synchrotron radiation-based micro X-ray fluorescence analysis combined with backscattered electron imaging

    International Nuclear Information System (INIS)

    Lu, Hongbin; Chen, Can; Wang, Zhanwen; Qu, Jin; Xu, Daqi; Wu, Tianding; Cao, Yong; Zhou, Jingyong; Zheng, Cheng; Hu, Jianzhong

    2015-01-01

    Tendon attaches to bone through a functionally graded fibrocartilage zone, including uncalcified fibrocartilage (UF), tidemark (TM) and calcified fibrocartilage (CF). This transition zone plays a pivotal role in relaxing load transfer between tendon and bone, and serves as a boundary between otherwise structurally and functionally distinct tissue types. Calcium and zinc are believed to play important roles in the normal growth, mineralization, and repair of the fibrocartilage zone of bone–tendon junction (BTJ). However, spatial distributions of calcium and zinc at the fibrocartilage zone of BTJ and their distribution–function relationship are not totally understood. Thus, synchrotron radiation-based micro X-ray fluorescence analysis (SR-μXRF) in combination with backscattered electron imaging (BEI) was employed to characterize the distributions of calcium and zinc at the fibrocartilage zone of rabbit patella–patellar tendon complex (PPTC). For the first time, the unique distributions of calcium and zinc at the fibrocartilage zone of the PPTC were clearly mapped by this method. The distributions of calcium and zinc at the fibrocartilage zone of the PPTC were inhomogeneous. A significant accumulation of zinc was exhibited in the transition region between UF and CF. The highest zinc content (3.17 times of that of patellar tendon) was found in the TM of fibrocartilage zone. The calcium content began to increase near the TM and increased exponentially across the calcified fibrocartilage region towards the patella. The highest calcium content (43.14 times of that of patellar tendon) was in the transitional zone of calcified fibrocartilage region and the patella, approximately 69 μm from the location with the highest zinc content. This study indicated, for the first time, that there is a differential distribution of calcium and zinc at the fibrocartilage zone of PPTC. These observations reveal new insights into region-dependent changes across the fibrocartilage

  7. 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

  8. Response of knee fibrocartilage to joint destabilization.

    Science.gov (United States)

    Dyment, N A; Hagiwara, Y; Jiang, X; Huang, J; Adams, D J; Rowe, D W

    2015-06-01

    A major challenge to understanding osteoarthritis (OA) pathology is identifying the cellular events that precede the onset of cartilage damage. The objective of this study is to determine the effect of joint destabilization on early changes to fibrocartilage in the joint. The anterior cruciate ligament was transected in collagen reporter mice (Col1CFP and ColXRFP). Mineralization labels were given every 2 weeks to measure new mineralized cartilage apposition. Novel fluorescent histology of mineralized tissue was used to characterize the changes in fibrocartilage at 2 and 4 weeks post-injury. Changes in fibrocartilaginous structures of the joint occur as early as 2 weeks after injury and are well developed by 4 weeks. The alterations are seen in multiple entheses and in the medial surface of the femoral and tibial condyles. In the responding entheses, mineral apposition towards the ligament midsubstance results in thickening of the mineralize fibrocartilage. These changes are associated with increases in ColX-RFP, Col1-CFP reporter activity and alkaline phosphatase enzyme activity. Mineral apposition also occurs in the fibrocartilage of the non-articular regions of the medial condyles by 2 weeks and develops into osteophytes by 4 weeks post-injury. An unexpected observation is punctate expression of tartrate resistant acid phosphatase activity in unmineralized fibrochondrocytes adjacent to active appositional mineralization. These observations suggest that fibrocartilage activates prior to degradation of the articular cartilage. Thus clinical and histological imaging of fibrocartilage may be an earlier indicator of disease initiation and may indicate a more appropriate time to start preventative treatment. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  9. Evaluation of TFC tears with magnetic resonance imaging; Comparison with arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Kushida, Manabu; Imamura, Koutaro; Sumi, Mitsuhiro; Uetani, Masataka (Nagasaki Univ. (Japan). School of Medicine); Nagatani, Yoshifumi

    1993-09-01

    This study evaluated the accuracy of magnetic resonance imaging (MRI) in the detection of tears of the trianglar fibrocartilage (TFC). Eighteen patients with chronic pain in the ulnar side of their wrist were examined by MRI and arthrography. Compared with arthrography, MRI was effective in the evaluation of TFC tears with a sensitivity of 92%, a specificity of 67%, and an accuracy of 83%. (author).

  10. [Environmental pollution by products of wear and tear automobile-road complex].

    Science.gov (United States)

    Levanchuk, A V

    2014-01-01

    North-West State Medical University named after I.I. Mechnikov, Saint Petersburg, Russian Federation, 191015. There is supposed the method for the assessment of amounts of pollutants released into the environment during the operational wear of tyre treads, brake system of cars and the road pavement. There are presented results of chemical analysis of residues of combustion. The necessity of control of products of work wear of automobile-road complex has been substantiated.

  11. Fibrocartilage in the attachment zones of the quadriceps tendon and patellar ligament of man.

    OpenAIRE

    Evans, E J; Benjamin, M; Pemberton, D J

    1990-01-01

    Differences are reported in the quantities and distribution of uncalcified fibrocartilage at the attachment sites of the quadriceps tendon and the patellar ligament. The largest quantity of fibrocartilage was characteristic of the quadriceps tendon. A prominent wedge of fibrocartilage was seen in the proximal part of the tibial attachment of the patellar ligament, though there was no fibrocartilage in the most superficial fibres. Little fibrocartilage was seen at the patellar attachment of th...

  12. 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.

  13. 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.

  14. Arthrography in lesions of triangular fibrocartilage of the wrist

    International Nuclear Information System (INIS)

    Rau, W.S.; Seifert, J.

    1982-01-01

    Arthography of the wrist is a safe method to demonstrate lesions of the triangular fibrocartilage. Indications are posttraumatic pain and restriction of movement of the wrist. Lesions of the triangular fibrocartilage are caused by a distal fracture of the radius with shortening, sudden drop on the overextended hand and work with rock drills. The extent of injury is quite different: small fissures and splits, detachment of the discus from the lower end of the ulna, fragmentation and destruction of the fibrocartilage. Problems of therapy, however, are greater than problems of diagnosis: actually there is no generally adopted surgical method for the treatment of discus lections. (orig./MG)

  15. Arthrography in lesions of triangular fibrocartilage of the wrist

    Energy Technology Data Exchange (ETDEWEB)

    Rau, W.S.; Seifert, J.

    1982-05-01

    Arthography of the wrist is a safe method to demonstrate lesions of the triangular fibrocartilage. Indications are posttraumatic pain and restriction of movement of the wrist. Lesions of the triangular fibrocartilage are caused by a distal fracture of the radius with shortening, sudden drop on the overextended hand and work with rock drills. The extent of injury is quite different: small fissures and splits, detachment of the discus from the lower end of the ulna, fragmentation and destruction of the fibrocartilage. Problems of therapy, however, are greater than problems of diagnosis: actually there is no generally adopted surgical method for the treatment of discus lesions.

  16. Electron microscopy of CO/sub 2/-laser-induced effects in human fibrocartilage

    Energy Technology Data Exchange (ETDEWEB)

    Whipple, T.L.; Marotta, J.J.; May, T.C.; Caspari, R.B.; Meyers, J.F.

    1987-01-01

    Previous reports of effects of CO/sub 2/ laser energy on human fibrocartilage suggest thermal injury extends to a depth of approximately 70 microns from the target surface with power settings of 35 W and exposure times of 0.5 seconds. The present study was undertaken to look for more subtle evidence of thermal alteration of human fibrocartilage treated with CO/sub 2/ laser irradiation. Fifteen human menisci were irradiated at power settings of 10, 20, and 30 W with exposure times of 0.1 and 0.5 seconds. The specimens were immediately fixed and sectioned for electron microscopic examination. Loss of a normal cross banding, and marginal clarity of individual collagen fibers were observed in the extracellular matrix and were observed at distances up to 300 microns from the exposed tissue surface. In addition, cellular changes at similar tissue depth consisted of cell membrane invaginations, clumping of nuclear chromatin, breakdown of endoplasmic reticulum architecture, and loss of mitochondria and Golgi complexes from the cytoplasm were observed. This study demonstrates deeper penetration of a radiation that was previously appreciated by light microscopy in irradiated human fibrocartilage, although the implications with respect to contraside viability and healing potential of the tissue in vivo is not known.

  17. Temporomandibular joint fibrocartilage degeneration from unilateral dental splints.

    Science.gov (United States)

    Henderson, Sarah E; Lowe, Jesse R; Tudares, Mauro A; Gold, Michael S; Almarza, Alejandro J

    2015-01-01

    The objective of this study was to determine the extent to which altered loading in the temporomandibular joint (TMJ), as might be associated with a malocclusion, drives degeneration of articulating surfaces in the TMJ. We therefore sought to quantify the effects of altered joint loading on the mechanical properties and biochemical content and distribution of TMJ fibrocartilage in the rabbit. Altered TMJ loading was induced with a 1mm splint placed unilaterally over the maxillary and mandibular molars for 6 weeks. At that time, TMJ fibrocartilage was assessed by compression testing, biochemical content (collagen, glycosaminoglycan (GAG), DNA) and distribution (histology), for both the TMJ disc and the condylar fibrocartilage. There were no changes in the TMJ disc for any of the parameters tested. The condylar fibrocartilage from the splinted animals was significantly stiffer and the DNA content was significantly lower than that in control animals. There was significant remodeling in the condylar fibrocartilage layers as manifested by a change in GAG and collagen II distribution and a loss of defined cell layers. A connection between the compressive properties of TMJ condylar fibrocartilage after 6 weeks of splinting and the changes in histology was observed. These results suggest a change in joint loading leads to condylar damage, which may contribute to pain associated with at least some forms of TMJ disease. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. 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: ...

  19. Mechanoactive scaffold induces tendon remodeling and expression of fibrocartilage markers.

    Science.gov (United States)

    Spalazzi, Jeffrey P; Vyner, Moira C; Jacobs, Matthew T; Moffat, Kristen L; Lu, Helen H

    2008-08-01

    Biological fixation of soft tissue-based grafts for anterior cruciate ligament (ACL) reconstruction poses a major clinical challenge. The ACL integrates with subchondral bone through a fibrocartilage enthesis, which serves to minimize stress concentrations and enables load transfer between two distinct tissue types. Functional integration thus requires the reestablishment of this fibrocartilage interface on reconstructed ACL grafts. We designed and characterized a novel mechanoactive scaffold based on a composite of poly-alpha-hydroxyester nanofibers and sintered microspheres; we then used the scaffold to test the hypothesis that scaffold-induced compression of tendon grafts would result in matrix remodeling and the expression of fibrocartilage interface-related markers. Histology coupled with confocal microscopy and biochemical assays were used to evaluate the effects of scaffold-induced compression on tendon matrix collagen distribution, cellularity, proteoglycan content, and gene expression over a 2-week period. Scaffold contraction resulted in over 15% compression of the patellar tendon graft and upregulated the expression of fibrocartilage-related markers such as Type II collagen, aggrecan, and transforming growth factor-beta3 (TGF-beta3). Additionally, proteoglycan content was higher in the compressed tendon group after 1 day. The data suggest the potential of a mechanoactive scaffold to promote the formation of an anatomic fibrocartilage enthesis on tendon-based ACL reconstruction grafts.

  20. Effect of the Interposition of Calcium Phosphate Materials on Tendon-Bone Healing During Repair of Chronic Rotator Cuff Tear.

    Science.gov (United States)

    Zhao, Song; Peng, Lingjie; Xie, Guoming; Li, Dingfeng; Zhao, Jinzhong; Ning, Congqin

    2014-08-01

    The current nature of tendon-bone healing after rotator cuff (RC) repair is still the formation of granulation tissue at the tendon-bone interface rather than the formation of fibrocartilage, which is the crucial structure in native tendon insertion and can be observed after knee ligament reconstruction. The interposition of calcium phosphate materials has been found to be able to enhance tendon-bone healing in knee ligament reconstruction. However, whether the interposition of these kinds of materials can enhance tendon-bone healing or even change the current nature of tendon-bone healing after RC repair still needs to be explored. The interposition of calcium phosphate materials during RC repair would enhance tendon-bone healing or change its current nature of granulation tissue formation into a more favorable process. Controlled laboratory study. A total of 144 male Sprague-Dawley rats underwent unilateral detachment of the supraspinatus tendon, followed by delayed repair after 3 weeks. The animals were allocated into 1 of 3 groups: (1) repair alone, (2) repair with Ca5(PO4)2SiO4 (CPS) bioceramic interposition, or (3) repair with hydroxyapatite (HA) bioceramic interposition at the tendon-bone interface. Animals were sacrificed at 2, 4, or 8 weeks postoperatively, and microcomputed tomography (micro-CT) was used to quantify the new bone formation at the repair site. New fibrocartilage formation and collagen organization at the tendon-bone interface was evaluated by histomorphometric analysis. Biomechanical testing of the supraspinatus tendon-bone complex was performed. Statistical analysis was performed using 1-way analysis of variance. Significance was set at P repair, CPS bioceramic significantly increased the area of fibrocartilage at the tendon-bone interface compared with the control and HA groups. Moreover, CPS and HA bioceramics had significantly improved collagen organization. Biomechanical tests indicated that the CPS and HA groups have greater ultimate

  1. Preparation and Characterization of a Novel Decellularized Fibrocartilage "Book" Scaffold for Use in Tissue Engineering.

    Directory of Open Access Journals (Sweden)

    Liyun Guo

    Full Text Available At the tendon-to-bone insertion, there is a unique transitional structure: tendon, non-calcified fibrocartilage, calcified fibrocartilage, and bone. The reconstruction of this special graded structure after defects or damage is an important but challenging task in orthopedics. In particular, reconstruction of the fibrocartilage zone has yet to be successfully achieved. In this study, the development of a novel book-shape scaffold derived from the extracellular matrix of fibrocartilage was reported. Specifically, fibrocartilage from the pubic symphysis was obtained from rabbits and sliced into the shape of a book (dimensions: 10 mm × 3 mm × 1 mm with 10 layers, each layer (akin to a page of a book with a thickness of 100-μm. These fibrocartilage "book" scaffolds were decellularized using sequentially 3 freeze-thaw cycles, 0.1% Triton X-100 with 1.5 M KCl, 0.25% trypsin, and a nuclease. Histology and DNA quantification analysis confirmed substantial removal of cells from the fibrocartilage scaffolds. Furthermore, the quantities of DNA, collagen, and glycosaminoglycan in the fibrocartilage were markedly reduced following decellularization. Scanning electron microscopy confirmed that the intrinsic ultrastructure of the fibrocartilage tissue was well preserved. Therefore, the results of this study suggest that the novel "book" fibrocartilage scaffold could have potential applications in tissue engineering.

  2. Preparation and Characterization of a Novel Decellularized Fibrocartilage "Book" Scaffold for Use in Tissue Engineering.

    Science.gov (United States)

    Guo, Liyun; Qu, Jin; Zheng, Cheng; Cao, Yong; Zhang, Tao; Lu, Hongbin; Hu, Jianzhong

    2015-01-01

    At the tendon-to-bone insertion, there is a unique transitional structure: tendon, non-calcified fibrocartilage, calcified fibrocartilage, and bone. The reconstruction of this special graded structure after defects or damage is an important but challenging task in orthopedics. In particular, reconstruction of the fibrocartilage zone has yet to be successfully achieved. In this study, the development of a novel book-shape scaffold derived from the extracellular matrix of fibrocartilage was reported. Specifically, fibrocartilage from the pubic symphysis was obtained from rabbits and sliced into the shape of a book (dimensions: 10 mm × 3 mm × 1 mm) with 10 layers, each layer (akin to a page of a book) with a thickness of 100-μm. These fibrocartilage "book" scaffolds were decellularized using sequentially 3 freeze-thaw cycles, 0.1% Triton X-100 with 1.5 M KCl, 0.25% trypsin, and a nuclease. Histology and DNA quantification analysis confirmed substantial removal of cells from the fibrocartilage scaffolds. Furthermore, the quantities of DNA, collagen, and glycosaminoglycan in the fibrocartilage were markedly reduced following decellularization. Scanning electron microscopy confirmed that the intrinsic ultrastructure of the fibrocartilage tissue was well preserved. Therefore, the results of this study suggest that the novel "book" fibrocartilage scaffold could have potential applications in tissue engineering.

  3. Attachment sites of the coracoclavicular ligaments are characterized by fibrocartilage differentiation: a study on human cadaveric tissue.

    Science.gov (United States)

    Ockert, B; Braunstein, V; Sprecher, C; Shinohara, Y; Kirchhoff, C; Milz, S

    2012-02-01

    We analyzed the immunohistochemical labeling patterns of the extracellular matrix of the coracoclavicular ligaments (CCL) in order to relate the molecular composition of the attachment sites to their mechanical environment. Ligaments were exposed from 12 fresh-frozen human cadaveric samples (four males, mean age: 48.6 ± 12.1 years). Cryosection of methanol-fixed and decalcified tissue was cut and sections were labeled with a panel of monoclonal antibodies directed against collagens, proteoglycans and proteins of vascular components. Attachment sites of both ligaments showed characteristic fibrocartilaginous labeling of collagen type II, aggrecan and link protein in all samples. Labeling for type II collagen was most conspicuous at the insertion of the coracoid process. Morphometry of adjacent samples revealed a fibrocartilage zone of 10-15% in relationship with the ligament proper, where labeling for type II collagen, aggrecan and link protein was negative. The presence of fibrocartilage at both entheses of the trapezoid and conoid ligament suggests that the CCL complex is subject to shear/compression forces. A variable fibrocartilage differentiation at the entheses of both ligaments may be related to the marked change in loading and insertion angle that the ligaments undergo during shoulder movement. © 2010 John Wiley & Sons A/S.

  4. Avascular necrosis of the lunate bone (Kienböck’s disease) secondary to scapholunate ligament tear as a consequence of trauma – a case study

    International Nuclear Information System (INIS)

    Kulhawik, Dorota; Szałaj, Tomasz; Grabowska, Monika

    2014-01-01

    Avascular necrosis of the lunate bone (Kienböck’s disease), is a condition in which lunate bone, loses its blood supply, leading to necrosis of the bone. There is probably no single cause of Kienbock’s disease. Its origin may involve multiple factors, such as the blood supply (arteries), blood drainage (veins), and skeletal variations. Trauma, either isolated or repeated, may possibly be a factor in some cases. This case presented with multifactorial etiology. In the presented case, a patient with negative ulnar variant had injured her right wrist and presented at an orthopedic clinic due to nonspecific pain 6 months later. An arthro-MRI examination revealed necrosis of the lunate bone, scapholunate ligament tear and coexisting TFCC (triangular fibrocartilage complex) tear. Early diagnosis and treatment can prevent progression of necrotic lesions and bone collapse. MRI examination seems to be the key diagnostic method in the early stage of the Kienböck’s disease with negative x-ray and CT images. Arthro-MRI examination also allows us to identify the underlying ligamentous injury. In cases of traumatic etiology, an additional CT test enables stating the final diagnosis

  5. Arthroscopic knotless anchor repair of triangular fibrocartilage in distal radius fracture.

    Science.gov (United States)

    García-Ruano, Á A; Najarro-Cid, F; Jiménez-Martín, A; Gómez de los Infantes-Troncoso, J G; Sicre-González, M

    2015-01-01

    Lesions of triangular fibrocartilage (TFC) are associated with distal radioulnar joint instability. Arthroscopic treatment of these lesions improves functional outcome of affected patients. The aim of the present work is to evaluate functional and occupational outcome of TCF repair using an arthroscopic knotless anchor device in patients with associated distal radius fracture. An observational, descriptive study was carried out between November 2011 and January 2014 including 21 patients with distal radius fracture and Palmer 1B lesions of TCF (Atzei class 2 and 3) that were treated by arthroscopic knotless anchor (PopLok® 2,8mm, ConMed, USA). Mean follow-up was 18 months. Functional (Mayo Wrist Score) and occupational outcome results were analyzed. Mean age of the group was 43.0±8.8 years, with 19% of the patients being female. There was an associated scapholunate lesion in 5 cases. Functional results reached a mean of 83.4±16.1 points onMayo Wrist Score. Mean sick-leave time was 153.16±48.5 days. Complete occupational reintegration was reached in 89.5% of cases. There were no postoperative complications. Arthroscopic knotless anchor repair of 1B TFC tears is a minimally invasive method of treatment that improves tension of fixation, avoiding subsequent loosen, in our experience, with few complications and good functional and occupational results. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

  6. Rotator cuff repair with a tendon-fibrocartilage-bone composite bridging patch.

    Science.gov (United States)

    Ji, Xiaoxi; Chen, Qingshan; Thoreson, Andrew R; Qu, Jin; An, Kai-Nan; Amadio, Peter C; Steinmann, Scott P; Zhao, Chunfeng

    2015-11-01

    To compare the mechanical performance of a rotator cuff repaired with a novel tendon-fibrocartilage-bone composite bridging patch vs the traditional Mason-Allen repair in an in vitro canine model. Twenty shoulders and 10 bridging patches from patellar tendon were harvested. The patches were trimmed and sliced into 2 layers. An infraspinatus tendon tear was created in each shoulder. Modified Mason-Allen sutures were used to repair the infraspinatus tendon to the greater tuberosity, with or without the bridging patch (bridging patch group and controls, respectively). Shoulders were loaded to failure under displacement control at a rate of 0.5mm/s. The ultimate tensile load was significantly higher in the bridging patch group than control (mean [SD], 365.46 [36.45] vs 272.79 [48.88] N; Pfibrocartilage-bone composite bridging patch achieved higher ultimate tensile load and stiffness at the patch-greater tuberosity repair site compared with traditional repair in a canine model. This composite tissue transforms the traditional tendon-to-bone healing interface (with dissimilar tissues) into a pair of bone-to-bone and tendon-to-tendon interfaces, which may improve healing quality and reduce retear rate. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. 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

  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. Avaliação artroscópica e macroscópica do complexo da fibrocartilagem triangular do punho. Estudo em cadáveres Arthroscopic and gross evaluation of the triangular fibrocartilage complex of the wrist: a cadaver-based study

    Directory of Open Access Journals (Sweden)

    Fabiano Inácio de Souza

    2006-01-01

    Full Text Available O complexo da fibrocartilagem triangular tem importante papel na biomecânica do punho. O diagnóstico preciso das lesões é fundamental para se obter sucesso no tratamento. Há controvérsias acerca da especificidade e sensibilidade dos métodos de imagem empregados atualmente. A artroscopia de punho é um método pouco empregado para o diagnóstico das lesões do CFCT em nosso meio, embora apresente grandes vantagens, como possibilidade de visão direta das lesões e tratamento no mesmo tempo cirúrgico. O objetivo deste estudo foi o de avaliar o papel da artroscopia de punho na inspeção do CFCT, bem como na detecção de possíveis lesões, comparando os dados com a dissecção macroscópica. Foram avaliados 15 punhos de cadáveres sexo masculino, média de idade de 56,1 anos. A artroscopia demonstrou presença de lesões em 33,3% dos punhos avaliados. Estes achados foram coincidentes após estudo anatômico com ampla dissecção. Concluímos que houve absoluta correlação entre o exame artroscópico e a dissecção macroscópica na detecção de lesões do CFCT.The triangular fibrocartilage complex plays a key role on wrist biomechanics. An accurate injuries diagnosis is paramount for a successful treatment. There are controversies regarding specificity and sensitiveness of imaging methods employed today. Wrist arthroscopy is a method uncommonly used for diagnosing TFCC injuries in our environment, although it presents good advantages, such as the potential of direct viewing injuries, and treatment at the same surgical time. The objective of this study was to evaluate the role of wrist arthroscopy for inspecting TFCC, as well as for detecting potential injuries, comparing those data to gross dissection. Fifteen wrists of male cadavers (mean age: 56.1 years old were assessed. Arthroscopy showed the presence of injuries in 33.3% of the assessed wrists. Those findings showed consistency after an anatomical study with broad dissection. We

  10. 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.

  11. Arthroscopic Wrist Anatomy

    National Research Council Canada - National Science Library

    Taylor, Nathan

    2004-01-01

    .... Arthroscopy of the wrist is now a primary method of evaluating and treating many intra-articular wrist conditions including triangular fibrocartilage complex tears, chondral injuries, distal radius...

  12. 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.

  13. 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.

  14. Electrostatic effect for the collisionless tearing mode

    International Nuclear Information System (INIS)

    Hoshino, M.

    1987-01-01

    Electron dynamics has not been self-consistently considered in collisionless tearing mode theories to date because of the mathematical complexity of the Vlasov-Maxwell equations. We have found using computer simulations that electrostatic fields play an important role in the tearing mode. Vlasov theory, including the electrostatic field, is investigated for topologies with both antiparallel and nonantiparallel magnetic field lines. The electrostatic field influences the resonant current in the neutral sheet which is a non-MHD effect, and modifies the linear growth rate. At the magnetopause, where the field lines are not antiparallel, the electrostatic effect acts to raise the linear growth rate of the tearing mode. On the other hand, in the magnetotail, where magnetic field lines are antiparallel, the electrostatic effect reduces the tearing mode growth rate. copyright American Geophysical Union 1987

  15. Partial Thickness Rotator Cuff Tears: Current Concepts

    Science.gov (United States)

    Matthewson, Graeme; Beach, Cara J.; Nelson, Atiba A.; Woodmass, Jarret M.; Ono, Yohei; Boorman, Richard S.; Lo, Ian K. Y.; Thornton, Gail M.

    2015-01-01

    Partial thickness rotator cuff tears are a common cause of pain in the adult shoulder. Despite their high prevalence, the diagnosis and treatment of partial thickness rotator cuff tears remains controversial. While recent studies have helped to elucidate the anatomy and natural history of disease progression, the optimal treatment, both nonoperative and operative, is unclear. Although the advent of arthroscopy has improved the accuracy of the diagnosis of partial thickness rotator cuff tears, the number of surgical techniques used to repair these tears has also increased. While multiple repair techniques have been described, there is currently no significant clinical evidence supporting more complex surgical techniques over standard rotator cuff repair. Further research is required to determine the clinical indications for surgical and nonsurgical management, when formal rotator cuff repair is specifically indicated and when biologic adjunctive therapy may be utilized. PMID:26171251

  16. Partial Thickness Rotator Cuff Tears: Current Concepts

    Directory of Open Access Journals (Sweden)

    Graeme Matthewson

    2015-01-01

    Full Text Available Partial thickness rotator cuff tears are a common cause of pain in the adult shoulder. Despite their high prevalence, the diagnosis and treatment of partial thickness rotator cuff tears remains controversial. While recent studies have helped to elucidate the anatomy and natural history of disease progression, the optimal treatment, both nonoperative and operative, is unclear. Although the advent of arthroscopy has improved the accuracy of the diagnosis of partial thickness rotator cuff tears, the number of surgical techniques used to repair these tears has also increased. While multiple repair techniques have been described, there is currently no significant clinical evidence supporting more complex surgical techniques over standard rotator cuff repair. Further research is required to determine the clinical indications for surgical and nonsurgical management, when formal rotator cuff repair is specifically indicated and when biologic adjunctive therapy may be utilized.

  17. 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.

  18. 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

  19. Improved identification of the palmar fibrocartilage of the navicular bone with saline magnetic resonance bursography.

    Science.gov (United States)

    Schramme, Michael; Kerekes, Zoltan; Hunter, Stuart; Nagy, Krisztina; Pease, Anthony

    2009-01-01

    Fibrocartilage degeneration is the earliest pathologic finding in navicular disease but remains difficult to detect, even with magnetic resonance (MR) imaging. We hypothesized that injection of the navicular bursa with saline would improve accuracy of MR imaging evaluation of palmar fibrocartilage. Thoracic limbs were collected from 11 horses within 6 h of death. Imaging was performed with a 1.5 T magnet using sagittal 2D proton density and transverse 3D FLASH sequences with fat saturation. For the purpose of determining sensitivity and specificity of the MR images, fibrocartilage was classified as normal or abnormal, based on combination of the findings of gross and microscopic pathology. Thickness of fibrocartilage was measured on histologic sections and corresponding transverse FLASH MR images before and after injection of saline. A paired Student's t-test was used for comparison of measurements. Partial thickness fibrocartilage loss was present in 6 of 22 limbs. Sensitivity of precontrast MR images for detection of lesions was 100% while specificity was 6%. Saline MR arthrography resulted in both sensitivity and specificity of 100% based on consensus review. Mean histologic fibrocartilage thickness was 0.75 +/- 0.12 mm. Mean fibrocartilage thickness on precontrast transverse FLASH images was 0.93 +/- 0.065 and 0.73 +/- 0.09 mm on postsaline images. The histologic cartilage thickness was signficantly different from that in precontrast images (Pfibrocartilage can only be evaluated reliably for the presence of partial thickness lesions after intrabursal injection of saline.

  20. Extracorporeal shockwave enhanced regeneration of fibrocartilage in a delayed tendon-bone insertion repair model.

    Science.gov (United States)

    Chow, Dick Ho Kiu; Suen, Pui Kit; Huang, Le; Cheung, Wing-Hoi; Leung, Kwok-Sui; Ng, Chun; Shi, San Qiang; Wong, Margaret Wan Nar; Qin, Ling

    2014-04-01

    Fibrous tissue is often formed in delayed healing of tendon bone insertion (TBI) instead of fibrocartilage. Extracorporeal shockwave (ESW) provides mechanical cues and upregulates expression of fibrocartilage-related makers and cytokines. We hypothesized that ESW would accelerate fibrocartilage regeneration at the healing interface in a delayed TBI healing model. Partial patellectomy with shielding at the TBI interface was performed on 32 female New Zealand White Rabbits for establishing this delayed TBI healing model. The rabbits were separated into the control and ESW group for evaluations at postoperative week 8 and 12. Shielding was removed at week 4 and a single ESW treatment was applied at week 6. Fibrocartilage regeneration was evaluated histomorphologically and immunohistochemically. Vickers hardness of the TBI matrix was measured by micro-indentation. ESW group showed higher fibrocartilage area, thickness, and proteoglycan deposition than the control in week 8 and 12. ESW increased expression of SOX9 and collagen II significantly in week 8 and 12, respectively. ESW group showed a gradual transition of hardness from bone to fibrocartilage to tendon, and had a higher Vickers hardness than the control group at week 12. In conclusion, ESW enhanced fibrocartilage regeneration at the healing interface in a delayed TBI healing model. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  1. In vitro engineering of fibrocartilage using CDMP1 induced dermal fibroblasts and polyglycolide.

    Science.gov (United States)

    Zhao, Guiqing; Yin, Shuo; Liu, Guangpeng; Cen, Lian; Sun, Jian; Zhou, Heng; Liu, Wei; Cui, Lei; Cao, Yilin

    2009-07-01

    This study was designed to explore the feasibility of using cartilage-derived morphogenetic protein-1 (CDMP1) induced dermal fibroblasts (DFs) as seed cells and polyglycolide (PGA) as scaffold for fibrocartilage engineering. DFs isolated from canine were expanded and seeded on PGA scaffold to fabricate cell/scaffold constructs which were cultured with or without CDMP1. Proliferation and differentiation of DFs in different constructs were determined by DNA assay and glycosaminoglycan (GAG) production. Histological and immunohistochemical staining of the constructs after being in vitro cultured for 4 and 6 weeks were carried out to observe the fibrocartilage formation condition. The fibrocartilage-specific gene expression by cells in the constructs was analyzed by real-time PCR. It was shown that in the presence of CDMP1 the proliferation and GAG synthesis of DFs were significantly enhanced compared to those without CDMP1. Fibrocartilage-like tissue was formed in the CDMP1 induced construct after being cultured for 4 weeks, and it became more matured at 6 weeks as stronger staining for GAG and higher gene expression of collagen type II was observed. Since only weak staining for GAG and collagen type II was observed for the construct engineered without CDMP1, the induction effect on the fibrocartilage engineering can be ascertained when using DFs as seed cells. Furthermore, the potential of using DFs as seed cells to engineer fibrocartilage is substantiated and further study on using the engineered tissue to repair fibrocartilage defects is currently ongoing in our group.

  2. 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.

  3. 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.

  4. Optimizing gelling parameters of gellan gum for fibrocartilage tissue engineering.

    Science.gov (United States)

    Lee, Haeyeon; Fisher, Stephanie; Kallos, Michael S; Hunter, Christopher J

    2011-08-01

    Gellan gum is an attractive biomaterial for fibrocartilage tissue engineering applications because it is cell compatible, can be injected into a defect, and gels at body temperature. However, the gelling parameters of gellan gum have not yet been fully optimized. The aim of this study was to investigate the mechanics, degradation, gelling temperature, and viscosity of low acyl and low/high acyl gellan gum blends. Dynamic mechanical analysis showed that increased concentrations of low acyl gellan gum resulted in increased stiffness and the addition of high acyl gellan gum resulted in greatly decreased stiffness. Degradation studies showed that low acyl gellan gum was more stable than low/high acyl gellan gum blends. Gelling temperature studies showed that increased concentrations of low acyl gellan gum and CaCl₂ increased gelling temperature and low acyl gellan gum concentrations below 2% (w/v) would be most suitable for cell encapsulation. Gellan gum blends were generally found to have a higher gelling temperature than low acyl gellan gum. Viscosity studies showed that increased concentrations of low acyl gellan gum increased viscosity. Our results suggest that 2% (w/v) low acyl gellan gum would have the most appropriate mechanics, degradation, and gelling temperature for use in fibrocartilage tissue engineering applications. Copyright © 2011 Wiley Periodicals, Inc.

  5. 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

  6. Preparation and Characterization of a Novel Decellularized Fibrocartilage “Book” Scaffold for Use in Tissue Engineering

    Science.gov (United States)

    Guo, Liyun; Qu, Jin; Zheng, Cheng; Cao, Yong; Zhang, Tao; Lu, Hongbin; Hu, Jianzhong

    2015-01-01

    At the tendon-to-bone insertion, there is a unique transitional structure: tendon, non-calcified fibrocartilage, calcified fibrocartilage, and bone. The reconstruction of this special graded structure after defects or damage is an important but challenging task in orthopedics. In particular, reconstruction of the fibrocartilage zone has yet to be successfully achieved. In this study, the development of a novel book-shape scaffold derived from the extracellular matrix of fibrocartilage was reported. Specifically, fibrocartilage from the pubic symphysis was obtained from rabbits and sliced into the shape of a book (dimensions: 10 mm × 3 mm × 1 mm) with 10 layers, each layer (akin to a page of a book) with a thickness of 100-μm. These fibrocartilage “book” scaffolds were decellularized using sequentially 3 freeze-thaw cycles, 0.1% Triton X-100 with 1.5 M KCl, 0.25% trypsin, and a nuclease. Histology and DNA quantification analysis confirmed substantial removal of cells from the fibrocartilage scaffolds. Furthermore, the quantities of DNA, collagen, and glycosaminoglycan in the fibrocartilage were markedly reduced following decellularization. Scanning electron microscopy confirmed that the intrinsic ultrastructure of the fibrocartilage tissue was well preserved. Therefore, the results of this study suggest that the novel “book” fibrocartilage scaffold could have potential applications in tissue engineering. PMID:26636672

  7. [Histomorphological analyse of accelerating the fibrocartilage layer repair of patella-patellar tendon junction in rabbits by low intensity pulsed ultrasound stimulation].

    Science.gov (United States)

    Zhang, Baoliang; Lü, Hongbin; Hu, Jianzhong; Xu, Daqi; Zhou, Jingyong; Wang, Ye

    2013-08-01

    To analyse the effect of low intensity pulsed ultrasound stimulation (LIPUS) on accelerating the fibrocartilage layer repair of patella-patellar tendon junction. A total of 60 mature female New Zealand white rabbits undergoing standard partial patellectomy were divided into 2 groups randomly. The control group was given comfort treatment and the treatment group was given LIPUS treatment starting from day 3 to the end of week 6 postoperatively. The scheduled time points of animal euthanization would be at week 6, week 12 and week 18 postoperatively. The patella-patellar tendon (PPT) complex would be harvested and cut into sections after decalcification for H&E staining, Safranine o/fast green staining. The thickness and gray value of fibrocartilage layer were analyzed by SANO Microscope Partner image analyzer. At week 6, week 12 and week 18 postoperatively, the fibrocartilage layer in the treatment group was significantly thicker than that in the control group (Pfibrocartilage layer was significantly smaller than that in the control group (Pfibrocartilage layer repair of patella-patellar tendon junction in rabbit models.

  8. Identification of a progenitor cell population destined to form fracture fibrocartilage callus in Dickkopf-related protein 3-green fluorescent protein reporter mice.

    Science.gov (United States)

    Mori, Yu; Adams, Douglas; Hagiwara, Yusuke; Yoshida, Ryu; Kamimura, Masayuki; Itoi, Eiji; Rowe, David W

    2016-11-01

    Fracture healing is a complex biological process involving the proliferation of mesenchymal progenitor cells, and chondrogenic, osteogenic, and angiogenic differentiation. The mechanisms underlying the proliferation and differentiation of mesenchymal progenitor cells remain unclear. Here, we demonstrate Dickkopf-related protein 3 (Dkk3) expression in periosteal cells using Dkk3-green fluorescent protein reporter mice. We found that proliferation of mesenchymal progenitor cells began in the periosteum, involving Dkk3-positive cell proliferation near the fracture site. In addition, Dkk3 was expressed in fibrocartilage cells together with smooth muscle α-actin and Col3.6 in the early phase of fracture healing as a cell marker of fibrocartilage cells. Dkk3 was not expressed in mature chondrogenic cells or osteogenic cells. Transient expression of Dkk3 disappeared in the late phase of fracture healing, except in the superficial periosteal area of fracture callus. The Dkk3 expression pattern differed in newly formed type IV collagen positive blood vessels and the related avascular tissue. This is the first report that shows Dkk3 expression in the periosteum at a resting state and in fibrocartilage cells during the fracture healing process, which was associated with smooth muscle α-actin and Col3.6 expression in mesenchymal progenitor cells. These fluorescent mesenchymal lineage cells may be useful for future studies to better understand fracture healing.

  9. 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

  10. Hip Labral Tear

    Science.gov (United States)

    ... that joint in the future. Prevention Hip labral tears are often associated with sports participation. If your sport puts a lot of strain on your hips, condition the surrounding muscles with strength and flexibility exercises. Try to avoid ...

  11. Haemolacria (bloody tears)

    African Journals Online (AJOL)

    PROF. EZECHUKWU

    2014-08-06

    Aug 6, 2014 ... menstruation, drugs, hyperthyroidism, nasolacrimal tu- berculosis ... no bleeding from any other body orifice. However ... All age groups can be affected from infancy to ... the system and thus lead to bloody tears emerging from.

  12. Ultrastructure of the developing fibrocartilage of the os penis of rat.

    Science.gov (United States)

    Izumi, K; Yamaoka, I; Murakami, R

    2000-02-01

    Development of the fibrocartilage of the os penis of rat was studied by transmission electron microscopy. Prepubertal (0-4 weeks of development) and pubertal (4-8 weeks of development) males were examined. Effects of castration on the development of the fibrocartilage were also examined. During the first 0-4 weeks of development, cells in the primordium of the fibrocartilage became large and the cytoplasm had well-developed rough endoplasmic reticulum (rER) and many intermediate filaments. Collagen fibers increased markedly in amount in the extracellular matrix (ECM) during the period. For 4-6 weeks, when gonadal secretion of androgens increases, the cells developed into mature chondrocytes with lacunae. Collagenous bundles were pushed away from the lacunae, resulting in a characteristic appearance of this fibrocartilage. The cytoplasm of the mature chondrocytes of the fibrocartilage was characterized by many intermediate filaments, oil droplets, glycogen granules, and well-developed rER. At 6 weeks, calcification started on the cell membrane of the mature chondrocytes. At 8 weeks, a large part of the cartilage matrix was calcified. Matrix vesicles that originate from degenerated chondrocytes were found in the ECM of decalcified samples. In castrated males, cells of the primordium of the fibrocartilage ceased further development after castration. Intermediate filaments were still abundant in the cytoplasm and collagen fibers increased even after castration, but mature chondrocytes never differentiated. There were no signs of matrix vesicle formation, calcification, or cell degeneration in the fibrocartilage primordium. The developmental process of the fibrocartilage can be subdivided into two phases: collagenous matrix formation during the prepubertal period (0-4 weeks), and maturation of chondrocytes and calcification after puberty (4-8 weeks). Copyright 2000 Wiley-Liss, Inc.

  13. Fibrocartilage in various regions of the human glenoid labrum. An immunohistochemical study on human cadavers.

    Science.gov (United States)

    Ockert, Ben; Braunstein, Volker; Sprecher, Christoph M; Shinohara, Yasushi; Milz, Stefan

    2012-06-01

    The nature and the distribution of fibrocartilage at the human glenoid labrum are unclear, and a better understanding may help to restore its function in open and arthroscopic Bankart repair. Aim of this study was to describe the fibrocartilage extent within the labrum at clinically relevant sites of the glenoid in order to relate the molecular composition of the labrum to its mechanical environment. Twelve fresh frozen human cadaveric shoulders (mean age 38 years) were obtained, and sections perpendicular to the glenoid rim at the 12, 2, 3, 4, 6 and 9 o' clock position were labelled with antibodies against collagen I and II, aggrecan and link protein. A fibrocartilaginous transition zone with a characteristic collagen fibre orientation was found in 81% of cases, evenly distributed (83-92%) around the glenoid rim. The percentage of labrum cross-sectional area comprised of fibrocartilage averaged 28% and ranged from 26% at 12 o'clock on the glenoid clock face to 30% at 3 o'clock. The highest amount of fibrocartilage (82%) was found in the region neighbouring the hyaline articular cartilage. In the region beyond the bony edge of the glenoid, fibrocartilage cross-sectional area did not exceed 12-17%. Fibrocartilage is present at all examined positions around the glenoid rim and constitutes up to 1/3 of the cross-sectional area of the labrum. In turn, the percentage of fibrocartilage in different regions of its cross-section varies considerably. The findings suggest that the penetration of fibrocartilaginous tissue may be reduced by avoiding the highly fibrocartilage transition zone during restoration of labral detachment.

  14. 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.)

  15. 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.

  16. 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

  17. 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

  18. [CONDITIONS OF SYNOVIAL MESENCHYMAL STEM CELLS DIFFERENTIATING INTO FIBROCARTILAGE CELLS].

    Science.gov (United States)

    Fu, Peiliang; Cong, Ruijun; Chen, Song; Zhang, Lei; Ding, Zheru; Zhou, Qi; Li, Lintao; Xu, Zhenyu; Wu, Yuli; Wu, Haishan

    2015-01-01

    To explore the conditions of synovial derived mesenchymal stem cells (SMSCs) differentiating into the fibrocartilage cells by using the orthogonal experiment. The synovium was harvested from 5 adult New Zealand white rabbits, and SMSCs were separated by adherence method. The flow cytometry and multi-directional differentiation method were used to identify the SMSCs. The conditions were found from the preliminary experiment and literature review. The missing test was carried out to screen the conditions and then 12 conditions were used for the orthogonal experiment, including transforming growth factor β1 (TGF-β1), bone morphogenic protein 2 (BMP-2), dexamethasone (DEX), proline, ascorbic acid (ASA), pyruvic acid, insulin + transferrin + selenious acid pre-mixed solution (ITS), bovin serum albumin (BSA), basic fibroblast growth factor (bFGF), intermittent hydraulic pressure (IHP), bone morphogenic protein 7 (BMP-7), and insulin-like growth factor (IGF). The L60 (212) orthogonal experiment was designed using the SPSS 18.0 with 2 level conditions and the cells were induced to differentiate on the small intestinal submucosa (SIS)-3D scaffold. The CD151+/CD44+ cells were detected with the flow cytometry and then the differentiation rate was recorded. The immumohistochemical staining, cellular morphology, toluidine blue staining, and semi-quantitative RT-PCR examination for the gene expressions of sex determining region Y (SRY)-box 9 gene (Sox9), aggrecan gene (AGN), collagen type I gene (Col I), collagen type II gene (Col II), collagen type IX gene (Col IX) were used for result confirmation. The differentiation rate was calculated as the product of CD151/CD44+ cells and cells with Col I high expression. The grow curve was detected with the DNA abundance using the PicoGreen Assay. The visual observation and the variances analysis among the variable were used to evaluate the result of the orthogonal experiment, 1 level interaction was considered. The q-test and the

  19. Growth factor effects on costal chondrocytes for tissue engineering fibrocartilage

    Science.gov (United States)

    Johns, D.E.; Athanasiou, K.A.

    2010-01-01

    Tissue engineered fibrocartilage could become a feasible option for replacing tissues like the knee meniscus or temporomandibular joint disc. This study employed five growth factors insulin-like growth factor-I, transforming growth factor-β1, epidermal growth factor, platelet-derived growth factor-BB, and basic fibroblast growth factor in a scaffoldless approach with costal chondrocytes, attempting to improve biochemical and mechanical properties of engineered constructs. Samples were quantitatively assessed for total collagen, glycosaminoglycans, collagen type I, collagen type II, cells, compressive properties, and tensile properties at two time points. Most treated constructs were worse than the no growth factor control, suggesting a detrimental effect, but the IGF treatment tended to improve the constructs. Additionally, the 6wk time point was consistently better than 3wks, with total collagen, glycosaminoglycans, and aggregate modulus doubling during this time. Further optimization of the time in culture and exogenous stimuli will be important in making a more functional replacement tissue. PMID:18597118

  20. 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.

  1. 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.)

  2. Fibrocartilage tissue engineering: the role of the stress environment on cell morphology and matrix expression.

    Science.gov (United States)

    Thomopoulos, Stavros; Das, Rosalina; Birman, Victor; Smith, Lester; Ku, Katherine; Elson, Elliott L; Pryse, Kenneth M; Marquez, Juan Pablo; Genin, Guy M

    2011-04-01

    Although much is known about the effects of uniaxial mechanical loading on fibrocartilage development, the stress fields to which fibrocartilaginous regions are subjected to during development are mutiaxial. That fibrocartilage develops at tendon-to-bone attachments and in compressive regions of tendons is well established. However, the three-dimensional (3D) nature of the stresses needed for the development of fibrocartilage is not known. Here, we developed and applied an in vitro system to determine whether fibrocartilage can develop under a state of periodic hydrostatic tension in which only a single principal component of stress is compressive. This question is vital to efforts to mechanically guide morphogenesis and matrix expression in engineered tissue replacements. Mesenchymal stromal cells in a 3D culture were exposed to compressive and tensile stresses as a result of an external tensile hydrostatic stress field. The stress field was characterized through mechanical modeling. Tensile cyclic stresses promoted spindle-shaped cells, upregulation of scleraxis and type one collagen, and cell alignment with the direction of tension. Cells experiencing a single compressive stress component exhibited rounded cell morphology and random cell orientation. No difference in mRNA expression of the genes Sox9 and aggrecan was observed when comparing tensile and compressive regions unless the medium was supplemented with the chondrogenic factor transforming growth factor beta3. In that case, Sox9 was upregulated under static loading conditions and aggrecan was upregulated under cyclic loading conditions. In conclusion, the fibrous component of fibrocartilage could be generated using only mechanical cues, but generation of the cartilaginous component of fibrocartilage required biologic factors in addition to mechanical cues. These studies support the hypothesis that the 3D stress environment influences cell activity and gene expression in fibrocartilage development.

  3. 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.

  4. Nonlinear drift tearing mode

    International Nuclear Information System (INIS)

    Zelenyj, L.M.; Kuznetsova, M.M.

    1989-01-01

    Nonlinear study of magnetic perturbation development under single-mode conditions in collision-free plasma in configurations with the magnetic field shear is investigated. Results are obtained with regard of transverse component of electrical field and its effect on ion dynamics within wide range of ion Larmor radius value and values of magnetic field shear. Increments of nonlinear drift tearing mode are obtained and it is shown that excitation drastic conditions of even linearly stable modes are possible. Mechanism of instability nonlinear stabilization is considered and the value of magnetic island at the saturation threshold is estimeted. Energy of nonlinear drift tearing mode is discussed

  5. Forced tearing of ductile and brittle thin sheets.

    Science.gov (United States)

    Tallinen, T; Mahadevan, L

    2011-12-09

    Tearing a thin sheet by forcing a rigid object through it leads to complex crack morphologies; a single oscillatory crack arises when a tool is driven laterally through a brittle sheet, while two diverging cracks and a series of concertinalike folds forms when a tool is forced laterally through a ductile sheet. On the other hand, forcing an object perpendicularly through the sheet leads to radial petallike tears in both ductile and brittle materials. To understand these different regimes we use a combination of experiments, simulations, and simple theories. In particular, we describe the transition from brittle oscillatory tearing via a single crack to ductile concertina tearing with two tears by deriving laws that describe the crack paths and wavelength of the concertina folds and provide a simple phase diagram for the morphologies in terms of the material properties of the sheet and the relative size of the tool.

  6. Tears of Wine

    Science.gov (United States)

    Gugliotti, Marcos

    2004-01-01

    The unique occurrence of the upward motion of a thin film of wine, and its formation into drops inside the wall of a wine glass is explained. Evaporation of alcohol generates a surface tension gradient, moving the film of wine upwards on the internal sides of a wine glass, where it collects and forms into drops or tears.

  7. 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...

  8. Craniocervical junction in dogs revisited--new ligaments and confirmed presence of enthesis fibrocartilage.

    Science.gov (United States)

    Kupczynska, M; Wieladek, A; Janczyk, P

    2012-06-01

    The study was performed to investigate and to describe features of gross and microscopic morphology of craniocervical junction (CCJ) in dogs. Seventy mature dogs (38 females, 32 males) of different body weight, representing small, medium and large breeds of dolicho-, mesati-, and brachycephalic morphotype were dissected. Morphological details were localised using an operating microscope with integrated video channel. Occurrence and distribution of fibrocartilage in the ligaments from 10 dogs was analysed histologically. Three new pairs of ligaments were described and named: dorsal ligaments of atlas, cranial internal collateral ligaments of atlas, and caudal internal collateral ligaments of atlas. Several new findings in the course of the known ligaments were found relating to breed and body weight. For the first time enthesis fibrocartilage was identified in ligaments of CCJ in dogs. Sesamoidal fibrocartilage was identified in the transversal ligament of atlas in large dogs. The findings are discussed for clinical importance. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Kartogenin with PRP promotes the formation of fibrocartilage zone in the tendon-bone interface.

    Science.gov (United States)

    Zhou, Yiqin; Zhang, Jianying; Yang, Jinsong; Narava, Manoj; Zhao, Guangyi; Yuan, Ting; Wu, Haishan; Zheng, Nigel; Hogan, MaCalus V; Wang, James H-C

    2017-12-01

    Treatment of tendon-bone junction injuries is a challenge because tendon-bone interface often heals poorly and the fibrocartilage zone, which reduces stress concentration, at the interface is not formed. In this study, we used a compound called kartogenin (KGN) with platelet-rich plasma (PRP) to induce the formation of fibrocartilage zone in a rat tendon graft-bone tunnel model. The experimental rats received KGN-PRP or PRP injections in the tendon graft-bone tunnel interface. The control group received saline. After 4, 8 and 12 weeks, Safranin O staining of the tendon graft-bone tunnels revealed abundant proteoglycans in the KGN-PRP group indicating the formation of cartilage-like transition zone. Immunohistochemical and immuno-fluorescence staining revealed collagen types I (Col-I) and II (Col-II) in the newly formed fibrocartilage zone. Both fibrocartilage zone formation and maturation were healing time dependent. In contrast, the PRP and saline control groups had no cartilage-like tissues and minimal Col-I and Col-II staining. Some gaps were also present in the saline control group. Finally, pull-out strength in the KGN-PRP-treated group at 8 weeks was 1.4-fold higher than the PRP-treated group and 1.6-fold higher than the saline control group. These findings indicate that KGN, with PRP as a carrier, promotes the formation of fibrocartilage zone between the tendon graft and bone interface. Thus, KGN-PRP may be used as a convenient cell-free therapy in clinics to promote fibrocartilage zone formation in rotator calf repair and anterior cruciate ligament reconstruction, thereby enhancing the mechanical strength of the tendon-bone interface and hence the clinical outcome of these procedures. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  10. [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.

  11. Pele's tears and spheres

    Science.gov (United States)

    Porritt, L. A.; Quane, S.; Russell, K.

    2011-12-01

    Pele's tears are a well known curiosity commonly associated with low viscosity basaltic explosive eruptions. However, these pyroclasts are rarely studied in detail and there is no full explanation for their formation. These intriguing pyroclasts have smooth glassy surfaces, vesiculated interiors, and fluidal morphologies tending towards droplets and then spheres as they decrease in size to Pele's tears from the 1959 fire-fountaining eruption of Kilauea Iki involving size and density measurements. Using thin section and SEM analysis we also consider their internal and external morphologies, porosity and bubble size distributions, and surface textures. Finally we consider the mechanisms of magma fragmentation, timescales of relaxation, and cooling rates that are responsible for their formation.

  12. Triangular fibrocartilage lesions: comparison STIR sequence versus arthroscopy findings

    International Nuclear Information System (INIS)

    Wang Zhi; Meng; Xianghong; Wang Linsen; Suo Yongmei

    2013-01-01

    Objective: To explore the diagnostic value of short TI inversion recovery (STIR) sequence in evaluating triangular fibrocartilage (TFC) lesions, and to compare the findings with the arthroscopy findings. Materials and Methods: Wrist joint MR examination using STIR sequence and arthroscopy were performed in 56 patients with TFC lesions. The parameters of STIR sequence were: TR: 1164 ms, TE: 16 ms, and TI: 90 ms. The sensibility, specificity, positive predictive value, negative predictive value, and accuracy in the diagnosis of TFC lesions with STIR sequence were calculated, using arthroscopy as the standard. Results: (1) STIR manifested 10 patients with normal TFC; 6 with small edema or mucous degeneration in the body portion but not involving joint surface edge; 6 with horizontal avulsion in the body portion, but not involving joint surface edge; 6 with avulsion involving joint surface edge; 11 with perforation in central portion; 6 with avulsion in radial attached end; 5 with avulsion in ulnar attached end; 3 with avulsion in both radial and ulnar attached ends; 3 with irregular shape and thin on the whole TFC. (2) Arthroscopy manifested 21 patients with normal TFC; 8 with avulsion involving joint surface edge; 10 with perforation in central portion; 7 with avulsion in radial attached end; 5 with avulsion in ulnar attached end; 2 with avulsion in both radial and ulnar attached ends; 3 with irregular shape on the whole TFC. Using STIR sequence, the sensibility, specificity, positive predictive value, negative predictive value. and accuracy were 85.7%, 23.8%, 65.2%, 50%, and 62.5%, respectively, in detection of TFC lesions, with arthroscopy as the standard. Conclusion: STIR sequence has high diagnostic value in detection of TFC lesions. (authors)

  13. The structure of the coracoacromial ligament: fibrocartilage differentiation does not necessarily mean pathology.

    Science.gov (United States)

    Milz, S; Jakob, J; Büttner, A; Tischer, T; Putz, R; Benjamin, M

    2008-02-01

    The coracoacromial ligament forms part of the coracoacromial arch and is implicated in impingement syndrome and acromial spur formation. Here, we describe its structure and the composition of its extracellular matrix. Ligaments were obtained from 15 cadavers, nine from older people (average age 74.7 years) and six from younger individuals (average age 24.2 years). Cryosections of methanol-fixed tissue were cut and sections were immunolabelled with monoclonal antibodies against collagens, glycosaminoglycans, proteoglycans, matrix proteins and neurofilament proteins. Both ligament entheses were highly fibrocartilaginous and immunolabelled strongly for type II collagen, aggrecan and link protein. The area of labelling was more extensive in older people. However, fibrocartilage also characterized the ligament midsubstance, particularly with increased age. Signs of fibrocartilage degeneration were more common in older people. Ligament fat (containing blood vessels and nerve fibers) was conspicuous in both age groups, especially between fiber bundles at the entheses. We conclude that fibrocartilage is a normal feature but becomes more pronounced with age. It is not necessarily pathological, for it simply indicates that the ligament is subject to compression and/or shear. Nevertheless, the prominence of fibrocartilage at the acromial enthesis may relate to the frequency with which enthesophytes develop.

  14. 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.

  15. 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

  16. Pectoralis major tears: anatomy, classification, and diagnosis with ultrasound and MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chiavaras, Mary M. [McMaster University, Department of Radiology, Hamilton, ON (Canada); Jacobson, Jon A. [University of Michigan, Department of Radiology, Ann Arbor, MI (United States); Smith, Jay [Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN (United States); Department of Radiology, Mayo Clinic, Rochester, MN (United States); Department of Anatomy, Mayo Clinic, Rochester, MN (United States); Dahm, Diane L. [Department of Orthopaedic Surgery, Mayo Clinic, Rochester, MN (United States)

    2014-09-09

    Accurate characterization of pectoralis major tears is important to guide management. Imaging evaluation with ultrasound and MR imaging can be difficult given the complex regional anatomy. In addition, recent literature has redefined the anatomy of the distal pectoralis major. The purpose of this study is to review pectoralis major injuries taking into account new anatomic descriptions using ultrasound and MR imaging, including cadaveric dissection, surgically produced pectoralis tears, and clinical pectoralis tendon tear with surgical correlation. (orig.)

  17. Pectoralis major tears: anatomy, classification, and diagnosis with ultrasound and MR imaging

    International Nuclear Information System (INIS)

    Chiavaras, Mary M.; Jacobson, Jon A.; Smith, Jay; Dahm, Diane L.

    2015-01-01

    Accurate characterization of pectoralis major tears is important to guide management. Imaging evaluation with ultrasound and MR imaging can be difficult given the complex regional anatomy. In addition, recent literature has redefined the anatomy of the distal pectoralis major. The purpose of this study is to review pectoralis major injuries taking into account new anatomic descriptions using ultrasound and MR imaging, including cadaveric dissection, surgically produced pectoralis tears, and clinical pectoralis tendon tear with surgical correlation. (orig.)

  18. Determination of Ductile Tearing Resistance Curve in Weld Joints

    International Nuclear Information System (INIS)

    Marie, S.; Gilles, P.; Ould, P.

    2010-01-01

    Steels present in the ductile domain a tearing resistance which increase with the crack propagation up to the failure. This ductile tearing resistance is in general characterised with curves giving the variation of a global parameter (opening displacement at the crack tip delta, integral J) versus the crack extension Delta a. These global approaches depend more or less on the specimen geometry and on the type of the imposed loading. Local approaches based on the description of the ductile tearing mechanisms provide reliable solution to the transferability problem (from the lab specimen to the component) but are complex and costly to use and are not codified. These problems get worse in the case of a weld joint where no standard is available for the measurement of their ductile tearing resistance. But the welded joints are often the weak point of the structure because of greater risk of defects, the heterogeneity of the microstructure of the weld, deformation along the interface between two materials with different yield stress (mismatch).... After briefly recalling the problems of transferability of the ductile tearing resistance curves obtained on lab specimen to the case of components, this article identifies the factors complicating the determination of the toughness in the welded joints and gives recommendations for the experimental determination of ductile tearing resistance curves of welded joints

  19. Interaction of lysozyme with a tear film lipid layer model: A molecular dynamics simulation study.

    Science.gov (United States)

    Wizert, Alicja; Iskander, D Robert; Cwiklik, Lukasz

    2017-12-01

    The tear film is a thin multilayered structure covering the cornea. Its outermost layer is a lipid film underneath of which resides on an aqueous layer. This tear film lipid layer (TFLL) is itself a complex structure, formed by both polar and nonpolar lipids. It was recently suggested that due to tear film dynamics, TFLL contains inhomogeneities in the form of polar lipid aggregates. The aqueous phase of tear film contains lachrymal-origin proteins, whereby lysozyme is the most abundant. These proteins can alter TFLL properties, mainly by reducing its surface tension. However, a detailed nature of protein-lipid interactions in tear film is not known. We investigate the interactions of lysozyme with TFLL in molecular details by employing coarse-grained molecular dynamics simulations. We demonstrate that lysozyme, due to lateral restructuring of TFLL, is able to penetrate the tear lipid film embedded in inverse micellar aggregates. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Peroneus longus tears associated with pathology of the os peroneum.

    Science.gov (United States)

    Stockton, Kristopher G; Brodsky, James W

    2014-04-01

    There is a range of different types of tears and pathology of the peroneal tendons. One of the least common types is the tear of the peroneus longus associated with fracture, enlargement, or entrapment at the cuboid tunnel of the os peroneum. The purpose of this study was to evaluate the pathologic patterns of these uncommon peroneal tendon tears, to review the treatment, and to report the patient outcomes following treatment with excision of the os peroneum, debridement, and tenodesis of the peroneus longus to the peroneus brevis. A 5-year retrospective review of all patients with peroneal tendon tears identified 12 patients operatively treated for peroneus longus tendon tears with associated pathology of the os peroneum, and in whom there was a viable peroneus brevis. All patients were treated with an operative procedure consisting of excision of the os peroneum, debridement, and tenodesis of the peroneus longus to the peroneus brevis. Mean age was 51.5 (range, 33 to 73) years, including 7 males and 5 females. Operative and radiographic records were reviewed to characterize the nature of the peroneus longus tears and associated pathology. Preoperative and postoperative AOFAS hindfoot, SF-36 questionnaires, and Visual Analog Scale (VAS) pain scores were compiled and patient records were reviewed for complications. Mean follow-up after surgery was 63.3 (range, 12 to 114) months. All of the patients had an os peroneum associated with a complex, irreparable tear of the peroneus longus tendon. The peroneus longus was typically enlarged, fibrotic, and adhered to the surrounding tissues. In 8 patients, the peroneus longus tendon tear was associated with a fracture of the os peroneum, and in 4 patients with an enlarged and entrapped os peroneum which prevented movement at the cuboid tunnel. Of the 12 patients, 9 had partial tears of the peroneus brevis, which were treated with debridement and suture repair. AOFAS hindfoot scores increased from a preoperative mean of 61

  1. Regional fibrocartilage variations in human anterior cruciate ligament tibial insertion: a histological three-dimensional reconstruction.

    Science.gov (United States)

    Dai, Can; Guo, Lin; Yang, Liu; Wu, Yi; Gou, Jingyue; Li, Bangchun

    2015-02-01

    We studied anterior cruciate ligament (ACL) tibial insertion architecture in humans and investigated regional differences that could suggest unequal force transmission from ligament to bone. ACL tibial insertions were processed histologically. With Photoshop software, digital images taken from the histological slides were collaged, contour lines were drawn, and different gray values were filled based on the structure. The data were exported to Amira software for three-dimensional reconstruction. The uncalcified fibrocartilage (UF) layer was divided into three regions: lateral, medial and posterior according to the architecture. The UF zone was significantly thicker laterally than medially or posteriorly (p fibrocartilage (CF) thickness was significantly greater in the lateral part of the enthesis compared to the medial and posterior parts (p < 0.05). The UF quantity (more UF laterally) corresponding to the CF quantity (more CF laterally) at the ACL tibial insertion provides further evidence suggesting that the load transferred from the ACL to the tibia was greater laterally than medially and posteriorly.

  2. Effect of platelet-rich plasma on fibrocartilage, cartilage, and bone repair in temporomandibular joint.

    Science.gov (United States)

    Kütük, Nükhet; Baş, Burcu; Soylu, Emrah; Gönen, Zeynep Burçin; Yilmaz, Canay; Balcioğlu, Esra; Özdamar, Saim; Alkan, Alper

    2014-02-01

    The purpose of the present study was to explore the potential use of platelet-rich-plasma (PRP) in the treatment of temporomandibular joint osteoarthritis (TMJ-OA). Surgical defects were created bilaterally on the condylar fibrocartilage, hyaline cartilage, and bone to induce an osteoarthritic TMJ in rabbits. PRP was applied to the right joints of the rabbits (PRP group), and the left joints received physiologic saline (control group). After 4 weeks, the rabbits were sacrificed for histologic and scanning electron microscopy (SEM) examinations. The data were analyzed statistically. The new bone regeneration was significantly greater in the PRP group (P fibrocartilage and hyaline cartilage was greater in the PRP group, no statistically significant difference was found between the 2 groups. SEM showed better ultrastructural architecture of the collagen fibrils in the PRP group. PRP might enhance the regeneration of bone in TMJ-OA. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Age-related carbonylation of fibrocartilage structural proteins drives tissue degenerative modification.

    Science.gov (United States)

    Scharf, Brian; Clement, Cristina C; Yodmuang, Supansa; Urbanska, Aleksandra M; Suadicani, Sylvia O; Aphkhazava, David; Thi, Mia M; Perino, Giorgio; Hardin, John A; Cobelli, Neil; Vunjak-Novakovic, Gordana; Santambrogio, Laura

    2013-07-25

    Aging-related oxidative stress has been linked to degenerative modifications in different organs and tissues. Using redox proteomic analysis and illustrative tandem mass spectrometry mapping, we demonstrate oxidative posttranslational modifications in structural proteins of intervertebral discs (IVDs) isolated from aging mice. Increased protein carbonylation was associated with protein fragmentation and aggregation. Complementing these findings, a significant loss of elasticity and increased stiffness was measured in fibrocartilage from aging mice. Studies using circular dichroism and intrinsic tryptophan fluorescence revealed a significant loss of secondary and tertiary structures of purified collagens following oxidation. Collagen unfolding and oxidation promoted both nonenzymatic and enzymatic degradation. Importantly, induction of oxidative modification in healthy fibrocartilage recapitulated the biochemical and biophysical modifications observed in the aging IVD. Together, these results suggest that protein carbonylation, glycation, and lipoxidation could be early events in promoting IVD degenerative changes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Exploiting endogenous fibrocartilage stem cells to regenerate cartilage and repair joint injury

    Science.gov (United States)

    Embree, Mildred C.; Chen, Mo; Pylawka, Serhiy; Kong, Danielle; Iwaoka, George M.; Kalajzic, Ivo; Yao, Hai; Shi, Chancheng; Sun, Dongming; Sheu, Tzong-Jen; Koslovsky, David A.; Koch, Alia; Mao, Jeremy J.

    2016-01-01

    Tissue regeneration using stem cell-based transplantation faces many hurdles. Alternatively, therapeutically exploiting endogenous stem cells to regenerate injured or diseased tissue may circumvent these challenges. Here we show resident fibrocartilage stem cells (FCSCs) can be used to regenerate and repair cartilage. We identify FCSCs residing within the superficial zone niche in the temporomandibular joint (TMJ) condyle. A single FCSC spontaneously generates a cartilage anlage, remodels into bone and organizes a haematopoietic microenvironment. Wnt signals deplete the reservoir of FCSCs and cause cartilage degeneration. We also show that intra-articular treatment with the Wnt inhibitor sclerostin sustains the FCSC pool and regenerates cartilage in a TMJ injury model. We demonstrate the promise of exploiting resident FCSCs as a regenerative therapeutic strategy to substitute cell transplantation that could be beneficial for patients suffering from fibrocartilage injury and disease. These data prompt the examination of utilizing this strategy for other musculoskeletal tissues. PMID:27721375

  5. In vitro study of stem cell communication via gap junctions for fibrocartilage regeneration at entheses.

    Science.gov (United States)

    Nayak, Bibhukalyan Prasad; Goh, James Cho Hong; Toh, Siew Lok; Satpathy, Gyan Ranjan

    2010-03-01

    Entheses are fibrocartilaginous organs that bridge ligament with bone at their interface and add significant insertional strength. To replace a severely damaged ligament, a tissue-engineered graft preinstalled with interfacial fibrocartilage, which is being regenerated from stem cells, appears to be more promising than ligament-alone graft. Such a concept can be realized by a biomimetic approach of establishing a dynamic communication of stem cells with bone cells and/or ligament fibroblasts in vitro. The current study has two objectives. The first objective is to demonstrate functional coculture of bone marrow-derived stem cells (BMSCs) with mature bone cells/ligament fibroblasts as evidenced by gap-junctional communication in vitro. The second objective is to investigate the role of BMSCs in the regeneration of fibrocartilage within the coculture. Rabbit bone/ligament fibroblasts were dual-stained with DiI-Red and calcein (gap-junction permeable dye), and cocultured with unlabeled BMSCs at fixed ratio (1:10). The functional gap junction was demonstrated by the transfer of calcein from donor to recipient cells that was confirmed and quantified by flow cytometry. Type 2 collagen (cartilage extracellular matrix-specific protein) expressed by the mixed cell lines in the cocultures were estimated by real-time reverse transcription PCR and compared with that of the ligament-bone coculture (control). Significant transfer of calcein into BMSCs was observed and flow cytometry analyses showed a gradual increase in the percentage of BMSCs acquiring calcein with time. Cocultures that included BMSCs expressed significantly more type 2 collagen compared with the control. The current study, for the first time, reported the expression of gap-junctional communication of BMSCs with two adherent cell lines of musculoskeletal system in vitro and also confirmed that incorporation of stem cells augments fibrocartilage regeneration. The results open up a path to envisage a composite

  6. [Self-assembly tissue engineering fibrocartilage model of goat temporomandibular joint disc].

    Science.gov (United States)

    Kang, Hong; Li, Zhen-Qiang; Bi, Yan-Da

    2011-06-01

    To construct self-assembly fibrocartilage model of goat temporomandibular joint disc and observe the biological characteristics of the self-assembled fibrocartilage constructs, further to provide a basis for tissue engineering of the temporomandibular joint disc and other fibrocartilage. Cells from temporomandibular joint discs of goats were harvested and cultured. 5.5 x 10(6) cells were seeded in each agarose well with diameter 5 mm x depth 10 mm, daily replace of medium, cultured for 2 weeks. One day after seeding, goat temporomandibular joint disc cells in agarose wells were gathered and began to self-assemble into a disc-shaped base, then gradually turned into a round shape. When cultured for 2 weeks, hematoxylin-eosin staining was conducted and observed that cells were round and wrapped around by the matrix. Positive Safranin-O/fast green staining for glycosaminoglycans was observed throughout the entire constructs, and picro-sirius red staining was examined and distribution of numerous type I collagen was found. Immunohistochemistry staining demonstrated brown yellow particles in cytoplasm and around extracellular matrix, which showed self-assembly construct can produce type I collagen as native temporomandibular joint disc tissue. Production of extracellular matrix in self-assembly construct as native temporomandibular joint disc tissue indicates that the use of agarose wells to construct engineered temporomandibular joint disc will be possible and practicable.

  7. Tensile loading modulates bone marrow stromal cell differentiation and the development of engineered fibrocartilage constructs.

    Science.gov (United States)

    Connelly, John T; Vanderploeg, Eric J; Mouw, Janna K; Wilson, Christopher G; Levenston, Marc E

    2010-06-01

    Mesenchymal progenitors such as bone marrow stromal cells (BMSCs) are an attractive cell source for fibrocartilage tissue engineering, but the types or combinations of signals required to promote fibrochondrocyte-specific differentiation remain unclear. The present study investigated the influences of cyclic tensile loading on the chondrogenesis of BMSCs and the development of engineered fibrocartilage. Cyclic tensile displacements (10%, 1 Hz) were applied to BMSC-seeded fibrin constructs for short (24 h) or extended (1-2 weeks) periods using a custom loading system. At early stages of chondrogenesis, 24 h of cyclic tension stimulated both protein and proteoglycan synthesis, but at later stages, tension increased protein synthesis only. One week of intermittent cyclic tension significantly increased the total sulfated glycosaminoglycan and collagen contents in the constructs, but these differences were lost after 2 weeks of loading. Constraining the gels during the extended culture periods prevented contraction of the fibrin matrix, induced collagen fiber alignment, and increased sulfated glycosaminoglycan release to the media. Cyclic tension specifically stimulated collagen I mRNA expression and protein synthesis, but had no effect on collagen II, aggrecan, or osteocalcin mRNA levels. Overall, these studies suggest that the combination of chondrogenic stimuli and tensile loading promotes fibrochondrocyte-like differentiation of BMSCs and has the potential to direct fibrocartilage development in vitro.

  8. 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)

  9. 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)

  10. Homologous structure-function relationships between native fibrocartilage and tissue engineered from MSC-seeded nanofibrous scaffolds.

    Science.gov (United States)

    Nerurkar, Nandan L; Han, Woojin; Mauck, Robert L; Elliott, Dawn M

    2011-01-01

    Understanding the interplay of composition, organization and mechanical function in load-bearing tissues is a prerequisite in the successful engineering of tissues to replace diseased ones. Mesenchymal stem cells (MSCs) seeded on electrospun scaffolds have been successfully used to generate organized tissues that mimic fibrocartilages such as the knee meniscus and the annulus fibrosus of the intervertebral disc. While matrix deposition has been observed in parallel with improved mechanical properties, how composition, organization, and mechanical function are related is not known. Moreover, how this relationship compares to that of native fibrocartilage is unclear. Therefore, in the present work, functional fibrocartilage constructs were formed from MSC-seeded nanofibrous scaffolds, and the roles of collagen and glycosaminoglycan (GAG) in compressive and tensile properties were determined. MSCs deposited abundant collagen and GAG over 120 days of culture, and these extracellular molecules were organized in such a way that they performed similar mechanical functions to their native roles: collagen dominated the tensile response while GAG was important for compressive properties. GAG removal resulted in significant stiffening in tension. A similar stiffening response was observed when GAG was removed from native inner annulus fibrosus, suggesting an interaction between collagen fibers and their surrounding extrafibrillar matrix that is shared by both engineered and native fibrocartilages. These findings strongly support the use of electrospun scaffolds and MSCs for fibrocartilage tissue engineering, and provide insight on the structure-function relations of both engineered and native biomaterials. Copyright © 2010 Elsevier Ltd. All rights reserved.

  11. Degenerative full thickness rotator cuff tears : Towards optimal management

    NARCIS (Netherlands)

    Lambers Heerspink, Frederik

    2016-01-01

    The shoulder is one of the most complex joints in the body. Besides a wide range of motion it also has to be stable. The rotator cuff is a major stabiliser of the glenohumoral joint. With increasing age rotator cuff tears are common. Successful treatment is described following surgical (rotator cuff

  12. 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

  13. 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.

  14. 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

  15. Treatment of Refractory Filamentary Keratitis With Autologous Serum Tears.

    Science.gov (United States)

    Read, Sarah P; Rodriguez, Marianeli; Dubovy, Sander; Karp, Carol L; Galor, Anat

    2017-09-01

    To report a case of filamentary keratitis (FK) successfully treated with autologous serum tears and to review the pathogenesis and management of FK. Case report including high-resolution anterior segment optical coherence tomography and filament histopathology. A 61-year-old Hispanic man presented with pain and photophobia of the right eye. He was found to have a corneal epithelial defect and a small peripheral infiltrate 4 months after Laser Assisted in situ Keratomileusis. After resolution of the epithelial defect, he developed FK. Over a 4-month period, conservative management with aggressive lubrication, lid hygiene, topical corticosteroids, topical cyclosporine, bandage contact lenses, and oral doxycycline failed to resolve the corneal filaments. Notably, treatment with 20% autologous serum tears, four times daily, led to a sustained resolution of the FK within 1 week. This case demonstrates the complexity of FK management and introduces autologous serum tears as a viable management option when conservative approaches to this condition fail.

  16. Non-mineralized fibrocartilage shows the lowest elastic modulus in the rabbit supraspinatus tendon insertion: measurement with scanning acoustic microscopy.

    Science.gov (United States)

    Sano, Hirotaka; Saijo, Yoshifumi; Kokubun, Shoichi

    2006-01-01

    The acoustic properties of rabbit supraspinatus tendon insertions were measured by scanning acoustic microscopy. After cutting parallel to the supraspinatus tendon fibers, specimens were fixed with 10% neutralized formalin, embedded in paraffin, and sectioned. Both the sound speed and the attenuation constant were measured at the insertion site. The 2-dimensional distribution of the sound speed and that of the attenuation constant were displayed with color-coded scales. The acoustic properties reflected both the histologic architecture and the collagen type. In the tendon proper and the non-mineralized fibrocartilage, the sound speed and attenuation constant gradually decreased as the predominant collagen type changed from I to II. In the mineralized fibrocartilage, they increased markedly with the mineralization of the fibrocartilaginous tissue. These results indicate that the non-mineralized fibrocartilage shows the lowest elastic modulus among 4 zones at the insertion site, which could be interpreted as an adaptation to various types of biomechanical stress.

  17. Duplex Tear Film Evaporation Analysis.

    Science.gov (United States)

    Stapf, M R; Braun, R J; King-Smith, P E

    2017-12-01

    Tear film thinning, hyperosmolarity, and breakup can cause irritation and damage to the human eye, and these form an area of active investigation for dry eye syndrome research. Recent research demonstrates that deficiencies in the lipid layer may cause locally increased evaporation, inducing conditions for breakup. In this paper, we explore the conditions for tear film breakup by considering a model for tear film dynamics with two mobile fluid layers, the aqueous and lipid layers. In addition, we include the effects of osmosis, evaporation as modified by the lipid, and the polar portion of the lipid layer. We solve the system numerically for reasonable parameter values and initial conditions and analyze how shifts in these cause changes to the system's dynamics.

  18. Randomized Controlled Study to Investigate the Effect of Topical Diquafosol Tetrasodium on Corneal Sensitivity in Short Tear Break-Up Time Dry Eye.

    Science.gov (United States)

    Kaido, Minako; Kawashima, Motoko; Shigeno, Yuta; Yamada, Yoshiaki; Tsubota, Kazuo

    2018-05-01

    Complex mechanisms underlie dry eye (DE) symptom provocation. In particular, corneal hypersensitivity may provoke symptoms in short tear break-up time (BUT) DE characterized by tear film instability. We hypothesized that improved tear film stability may alleviate corneal sensitivity in patients with short tear BUT DE. Therefore, we investigated the effect of topical diquafosol tetrasodium (DQS) on corneal sensitivity in unstable tear film DE. This prospective, randomized study included 27 subjects (age: 39.1 ± 8.4 years; range: 25-59 years) with short tear BUT DE, defined based on the presence of DE symptoms and tear film instability. Subjects were randomly divided into DQS (3% DQS, 12 subjects) and artificial tear (AT; preservative-free AT, 15 subjects) groups. Subjects applied the medication 6 times a day for 5 weeks. The perception of touch (S-touch) and pain (S-pain) sensitivity was measured using a Cochet-Bonnet esthesiometer. Tear evaluation, corneal sensitivity, and DE symptoms were compared before and after DQS or AT administration. The correlation between the improvement degrees of corneal sensitivity and DE symptoms following medication was analyzed. DQS significantly improved tear BUT and tear meniscus height (TMH) scores (p short tear BUT DE. However, DQS seems to be more effective to adjust tear environment, leading to the normalization of corneal sensitivity and DE symptoms. UMIN Clinical Trials Registry Identifier, UMIN000014536.

  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. Surface tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Takizuka, Tomonori; Kurita, Gen-ichi; Azumi, Masafumi; Takeda, Tatsuoki

    1985-10-01

    Surface tearing modes in tokamaks are studied numerically and analytically. The eigenvalue problem is solved to obtain the growth rate and the mode structure. We investigate in detail dependences of the growth rate of the m/n = 2/1 resistive MHD modes on the safety factor at the plasma surface, current profile, wall position, and resistivity. The surface tearing mode moves the plasma surface even when the wall is close to the surface. The stability diagram for these modes is presented. (author)

  1. Acute Medial Plantar Fascia Tear.

    Science.gov (United States)

    Pascoe, Stephanie C; Mazzola, Timothy J

    2016-06-01

    A 32-year-old man who participated in competitive soccer came to physical therapy via direct access for a chief complaint of plantar foot pain. The clinical examination findings and mechanism of injury raised a concern for a plantar fascia tear, so the patient was referred to the physician and magnetic resonance imaging was obtained. The magnetic resonance image confirmed a high-grade, partial-thickness, proximal plantar fascia tear with localized edema at the location of the medial band. J Orthop Sports Phys Ther 2016;46(6):495. doi:10.2519/jospt.2016.0409.

  2. A comparison of different bioinks for 3D bioprinting of fibrocartilage and hyaline cartilage.

    Science.gov (United States)

    Daly, Andrew C; Critchley, Susan E; Rencsok, Emily M; Kelly, Daniel J

    2016-10-07

    Cartilage is a dense connective tissue with limited self-repair capabilities. Mesenchymal stem cell (MSC) laden hydrogels are commonly used for fibrocartilage and articular cartilage tissue engineering, however they typically lack the mechanical integrity for implantation into high load bearing environments. This has led to increased interested in 3D bioprinting of cell laden hydrogel bioinks reinforced with stiffer polymer fibres. The objective of this study was to compare a range of commonly used hydrogel bioinks (agarose, alginate, GelMA and BioINK™) for their printing properties and capacity to support the development of either hyaline cartilage or fibrocartilage in vitro. Each hydrogel was seeded with MSCs, cultured for 28 days in the presence of TGF-β3 and then analysed for markers indicative of differentiation towards either a fibrocartilaginous or hyaline cartilage-like phenotype. Alginate and agarose hydrogels best supported the development of hyaline-like cartilage, as evident by the development of a tissue staining predominantly for type II collagen. In contrast, GelMA and BioINK ™ (a PEGMA based hydrogel) supported the development of a more fibrocartilage-like tissue, as evident by the development of a tissue containing both type I and type II collagen. GelMA demonstrated superior printability, generating structures with greater fidelity, followed by the alginate and agarose bioinks. High levels of MSC viability were observed in all bioinks post-printing (∼80%). Finally we demonstrate that it is possible to engineer mechanically reinforced hydrogels with high cell viability by co-depositing a hydrogel bioink with polycaprolactone filaments, generating composites with bulk compressive moduli comparable to articular cartilage. This study demonstrates the importance of the choice of bioink when bioprinting different cartilaginous tissues for musculoskeletal applications.

  3. 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

  4. Bifurcation of steady tearing states

    International Nuclear Information System (INIS)

    Saramito, B.; Maschke, E.K.

    1985-10-01

    We apply the bifurcation theory for compact operators to the problem of the nonlinear solutions of the 3-dimensional incompressible visco-resistive MHD equations. For the plane plasma slab model we compute branches of nonlinear tearing modes, which are stationary for the range of parameters investigated up to now

  5. Plate Tearing by a Cone

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup

    1997-01-01

    The present paper is concerned with steady-state plate tearing by a cone. This is a scenario where a cone is forced through a ductile metal plate with a constant lateral tip penetration in a motion in the plane of the plate. The considered process could be an idealisaton of the damage, which...... as for the out-of-plane reaction force....

  6. Energy balance in tearing modes

    International Nuclear Information System (INIS)

    Wesson, J.A.

    1993-01-01

    The energy balance in tearing modes is described in terms of exact separate energy balance equations. Each of these equations describes identified physical processes, and their sum gives the conservation of total energy. One of the energy balance equations corresponds to Furth's description. (Author)

  7. 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.)

  8. 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

  9. 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.

  10. Enthesis fibrocartilage cells originate from a population of Hedgehog-responsive cells modulated by the loading environment.

    Science.gov (United States)

    Schwartz, Andrea G; Long, Fanxin; Thomopoulos, Stavros

    2015-01-01

    Tendon attaches to bone across a specialized tissue called the enthesis. This tissue modulates the transfer of muscle forces between two materials, i.e. tendon and bone, with vastly different mechanical properties. The enthesis for many tendons consists of a mineralized graded fibrocartilage that develops postnatally, concurrent with epiphyseal mineralization. Although it is well described that the mineralization and development of functional maturity requires muscle loading, the biological factors that modulate enthesis development are poorly understood. By genetically demarcating cells expressing Gli1 in response to Hedgehog (Hh) signaling, we discovered a unique population of Hh-responsive cells in the developing murine enthesis that were distinct from tendon fibroblasts and epiphyseal chondrocytes. Lineage-tracing experiments revealed that the Gli1 lineage cells that originate in utero eventually populate the entire mature enthesis. Muscle paralysis increased the number of Hh-responsive cells in the enthesis, demonstrating that responsiveness to Hh is modulated in part by muscle loading. Ablation of the Hh-responsive cells during the first week of postnatal development resulted in a loss of mineralized fibrocartilage, with very little tissue remodeling 5 weeks after cell ablation. Conditional deletion of smoothened, a molecule necessary for responsiveness to Ihh, from the developing tendon and enthesis altered the differentiation of enthesis progenitor cells, resulting in significantly reduced fibrocartilage mineralization and decreased biomechanical function. Taken together, these results demonstrate that Hh signaling within developing enthesis fibrocartilage cells is required for enthesis formation. © 2015. Published by The Company of Biologists Ltd.

  11. A chondroitinase-ABC and TGF-β1 treatment regimen for enhancing the mechanical properties of tissue engineered fibrocartilage

    Science.gov (United States)

    MacBarb, Regina F.; Makris, Eleftherios A.; Hu, Jerry C.; Athanasiou, Kyriacos A.

    2012-01-01

    The development of functionally equivalent fibrocartilage remains elusive despite efforts to engineer tissues such as the knee menisci, intervertebral disc, and TMJ disc. Attempts to engineer these structures often fail to create tissues with mechanical properties on par with native tissue, resulting in constructs unsuitable for clinical applications. The objective of this study was to engineer a spectrum of biomimetic fibrocartilages representative of the distinct functional properties found in native tissues. Using the self-assembly process, different co-cultures of meniscus cells (MCs) and articular chondrocytes (ACs) were seeded into agarose wells and treated with the catabolic agent chondroitinase-ABC (C-ABC) and the anabolic agent transforming growth factor-β1 (TGF-β1) via a two-factor (cell ratio and bioactive treatment), full factorial study design. Application of both C-ABC and TGF-β1 resulted in a beneficial or positive increase in the collagen content of treated constructs compared to controls. Significant increases in both the collagen density and fiber diameter were also seen with this treatment, increasing these values 32% and 15%, respectively, over control values. Mechanical testing found the combined bioactive treatment to synergistically increase the Young’s modulus and ultimate tensile strength of the engineered fibrocartilages compared to controls, with values reaching the lower spectrum of those found in native tissues. Together, these data demonstrate that C-ABC and TGF-β1 interact to develop a denser collagen matrix better able to withstand tensile loading. This study highlights a way to optimize the tensile properties of engineered fibrocartilage using a biochemical and biophysical agent together to create distinct fibrocartilages with functional properties mimicking those of native tissue. PMID:23041782

  12. 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.

  13. 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

  14. Plate Tearing by a Cone

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup

    1998-01-01

    The present paper is concerned with steady-state plate tearing by a cone. This is a scenario where a cone is forced through a ductile metal plate with a constant lateral tip penetration in a motion in the plane of the plate. The considered process could be an idealisation of the damage, which...... as for the out-of-plane reaction force. (C) 1998 Elsevier Science Ltd. All rights reserved....

  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. 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)

  17. 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.)

  18. Novel Nano-Liposome Formulation for Dry Eyes with Components Similar to the Preocular Tear Film

    Directory of Open Access Journals (Sweden)

    Marta Vicario-de-la-Torre

    2018-04-01

    Full Text Available Dry eye is commonly treated with artificial tears; however, developing artificial tears similar to natural tears is difficult due to the complex nature of tears. We characterized and evaluated a novel artificial tear formulation with components similar to the lipid and aqueous constituents of natural tears. Nano-liposomes, composed in part of phosphatidylcholine, were dispersed in an aqueous solution of bioadhesive sodium hyaluronate. Liposome size, zeta potential, and physicochemical properties of the fresh and stored (4 °C liposomal formulation were analyzed. In vitro tolerance was tested using human corneal and conjunctival cell lines by exposures of 15 min to 4 h. The tolerance of the liposomal formulation was evaluated in animals (rabbits. The average liposome size was 186.3 ± 7.0 nm, and the zeta potential was negative. The osmolarity of the formulation was 198.6 ± 1.7 mOsm, with a surface tension of 36.5 ± 0.4 mN/m and viscosity of 3.05 ± 0.02 mPa·s. Viability values in the human corneal and conjunctival cell lines were always >80%, even after liposomal formulation storage for 8 weeks. Discomfort and clinical signs after instillation in rabbit eyes were absent. The new formulation, based on phosphatidylcholine-liposomes dispersed in sodium hyaluronate has suitable components and characteristics, including high in vitro cell viability and good in vivo tolerance, to serve as a tear substitute.

  19. 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...

  20. 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.

  1. 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

  2. Osteoid Osteoma Mimicking Triangular Fibrocartilage Complex Injury: Diagnosis and Review of Treatment

    Directory of Open Access Journals (Sweden)

    J. M. Lamo-Espinosa

    2012-01-01

    Full Text Available We report the case of osteoid osteoma (OO with ulnar styloid involvement. A review of the literature has been made with the aim of defining the special behaviour of OO when it is near the articular surface. That behaviour can affect the diagnosis, masking the real etiology of the pain, delaying the diagnosis, missing the diagnosis, or what is more serious, conducting an inadequate treatment. We propose a treatment algorithm conducted based on the localization near or far from articular surface and the superficial or deep localization.

  3. In-vitro ablation of fibrocartilage by XeCl excimer laser

    Science.gov (United States)

    Buchelt, Martin; Papaioannou, Thanassis; Fishbein, Michael C.; Peters, Werner; Beeder, Clain; Grundfest, Warren S.

    1991-07-01

    A 308 nm excimer laser was employed for ablation of human fibrocartilage. Experiments were conducted in vitro. The tissue response was investigated with respect to dosimetry (ablation rate versus radiant exposure) and thermal effect (thermographic analysis). Irradiation was performed via a 600 um fiber, with radiant exposures ranging between 20mj/mm2 and 80mj/mm2, at 20Hz. The ablation rates were found to range from 3um/pulse to 80um/pulse depending on the radiant exposure and/or the applied pressure on the delivery system. Thermographic analysis, during ablation, revealed maximum average temperatures of about 65 degree(s)C. Similar measurements performed, for the purpose of comparison, with a CW Nd:YAG and a CW CO2 laser showed higher values, of the order of 200 degree(s)C.

  4. Acute and chronic response of meniscal fibrocartilage to holmium:YAG laser irradiation

    Science.gov (United States)

    Horan, Patrick J.; Popovic, Neven A.; Islinger, Richard B.; Kuklo, Timothy R.; Dick, Edward J.

    1997-05-01

    The acute and chronic (10 week) histological effects of the holmium:YAG laser during partial meniscectomy in an in vivo rabbit model were investigated. Twenty-four adult male New Zealand rabbits underwent bilateral parapatellar medial knee arthrotomies. In the right knee, a partial medial meniscectomy was done through the avascular zone using a standard surgical blade. In the left knee, an anatomically similar partial medial meniscectomy was performed using a Ho:YAG laser (Coherent, USA). This study indicates that the laser creates two zones of damage in the meniscal fibrocartilage and that the zone of thermal change may act as a barrier to healing. The zone of thermal change which is eventually debrided was thought at the time of surgery to be viable. In the laser cut menisci, the synovium appears to have greater inflammation early and to be equivalent with the scalpel cut after three weeks. At all time periods there appeared more cellular damage in the laser specimens.

  5. Hyaline cartilage cells outperform mandibular condylar cartilage cells in a TMJ fibrocartilage tissue engineering application.

    Science.gov (United States)

    Wang, L; Lazebnik, M; Detamore, M S

    2009-03-01

    To compare temporomandibular joint (TMJ) condylar cartilage cells in vitro to hyaline cartilage cells cultured in a three-dimensional (3D) environment for tissue engineering of mandibular condylar cartilage. Mandibular condylar cartilage and hyaline cartilage cells were harvested from pigs and cultured for 6 weeks in polyglycolic acid (PGA) scaffolds. Both types of cells were treated with glucosamine sulfate (0.4 mM), insulin-like growth factor-I (IGF-I) (100 ng/ml) and their combination. At weeks 0 and 6, cell number, glycosaminoglycan (GAG) and collagen content were determined, types I and II collagen were visualized by immunohistochemistry and GAGs were visualized by histology. Hyaline cartilage cells produced from half an order to a full order of magnitude more GAGs and collagen than mandibular condylar cartilage cells in 3D culture. IGF-I was a highly effective signal for biosynthesis with hyaline cartilage cells, while glucosamine sulfate decreased cell proliferation and biosynthesis with both types of cells. In vitro culture of TMJ condylar cartilage cells produced a fibrous tissue with predominantly type I collagen, while hyaline cartilage cells formed a fibrocartilage-like tissue with types I and II collagen. The combination of IGF and glucosamine had a synergistic effect on maintaining the phenotype of TMJ condylar cells to generate both types I and II collagen. Given the superior biosynthetic activity by hyaline cartilage cells and the practical surgical limitations of harvesting cells from the TMJ of a patient requiring TMJ reconstruction, cartilage cells from elsewhere in the body may be a potentially better alternative to cells harvested from the TMJ for TMJ tissue engineering. This finding may also apply to other fibrocartilages such as the intervertebral disc and knee meniscus in applications where a mature cartilage cell source is desired.

  6. Assessment of growth factor treatment on fibrochondrocyte and chondrocyte co-cultures for TMJ fibrocartilage engineering.

    Science.gov (United States)

    Kalpakci, Kerem N; Kim, Eric J; Athanasiou, Kyriacos A

    2011-04-01

    Treatments for patients suffering from severe temporomandibular joint (TMJ) dysfunction are limited, motivating the development of strategies for tissue regeneration. In this study, co-cultures of fibrochondrocytes (FCs) and articular chondrocytes (ACs) were seeded in agarose wells, and supplemented with growth factors, to engineer tissue with biomechanical properties and extracellular matrix composition similar to native TMJ fibrocartilage. In the first phase, growth factors were applied alone and in combination, in the presence or absence of serum, while in the second phase, the best overall treatment was applied at intermittent dosing. Continuous treatment of AC/FC co-cultures with TGF-β1 in serum-free medium resulted in constructs with glycosaminoglycan/wet weight ratios (12.2%), instantaneous compressive moduli (790 kPa), relaxed compressive moduli (120 kPa) and Young's moduli (1.87 MPa) that overlap with native TMJ disc values. Among co-culture groups, TGF-β1 treatment increased collagen deposition ∼20%, compressive stiffness ∼130% and Young's modulus ∼170% relative to controls without growth factor. Serum supplementation, though generally detrimental to functional properties, was identified as a powerful mediator of FC construct morphology. Finally, both intermittent and continuous TGF-β1 treatment showed positive effects, though continuous treatment resulted in greater enhancement of construct functional properties. This work proposes a strategy for regeneration of TMJ fibrocartilage and its future application will be realized through translation of these findings to clinically viable cell sources. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  7. 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.

  8. 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.

  9. The social impact of emotional tears

    NARCIS (Netherlands)

    Vingerhoets, A.J.J.M.; van de Ven, N.; van der Velden, Y.

    2016-01-01

    The question what specific functions the production of emotional tears fulfills has received only limited attention of behavioral scientists. We report the results of two studies on the social impact of emotional tears. In Study 1 (96 Dutch females), perceived helplessness and felt connectedness

  10. 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

  11. 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.

  12. 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.

  13. 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.)

  14. 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.)

  15. 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)

  16. Gdf5 progenitors give rise to fibrocartilage cells that mineralize via hedgehog signaling to form the zonal enthesis.

    Science.gov (United States)

    Dyment, Nathaniel A; Breidenbach, Andrew P; Schwartz, Andrea G; Russell, Ryan P; Aschbacher-Smith, Lindsey; Liu, Han; Hagiwara, Yusuke; Jiang, Rulang; Thomopoulos, Stavros; Butler, David L; Rowe, David W

    2015-09-01

    The sequence of events that leads to the formation of a functionally graded enthesis is not clearly defined. The current study demonstrates that clonal expansion of Gdf5 progenitors contributes to linear growth of the enthesis. Prior to mineralization, Col1+ cells in the enthesis appose Col2+ cells of the underlying primary cartilage. At the onset of enthesis mineralization, cells at the base of the enthesis express alkaline phosphatase, Indian hedgehog, and ColX as they mineralize. The mineralization front then extends towards the tendon midsubstance as cells above the front become encapsulated in mineralized fibrocartilage over time. The hedgehog (Hh) pathway regulates this process, as Hh-responsive Gli1+ cells within the developing enthesis mature from unmineralized to mineralized fibrochondrocytes in response to activated signaling. Hh signaling is required for mineralization, as tissue-specific deletion of its obligate transducer Smoothened in the developing tendon and enthesis cells leads to significant reductions in the apposition of mineralized fibrocartilage. Together, these findings provide a spatiotemporal map of events - from expansion of the embryonic progenitor pool to synthesis of the collagen template and finally mineralization of this template - that leads to the formation of the mature zonal enthesis. These results can inform future tendon-to-bone repair strategies to create a mechanically functional enthesis in which tendon collagen fibers are anchored to bone through mineralized fibrocartilage. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Biochemical characterisation of navicular hyaline cartilage, navicular fibrocartilage and the deep digital flexor tendon in horses with navicular disease.

    Science.gov (United States)

    Viitanen, M; Bird, J; Smith, R; Tulamo, R-M; May, S A

    2003-10-01

    The study hypothesis was that navicular disease is a process analogous to degenerative joint disease, which leads to changes in navicular fibrocartilage and in deep digital flexor tendon (DDFT) matrix composition and that the process extends to the adjacent distal interphalangeal joint. The objectives were to compare the biochemical composition of the navicular articular and palmar cartilages from 18 horses with navicular disease with 49 horses with no history of front limb lameness, and to compare navicular fibrocartilage with medial meniscus of the stifle and collateral cartilage of the hoof. Cartilage oligomeric matrix protein (COMP), deoxyribonucleic acid (DNA), total glycosaminoglycan (GAG), metalloproteinases MMP-2 and MMP-9 and water content in tissues were measured. Hyaline cartilage had the highest content of COMP and COMP content in hyaline cartilage and tendon was higher in lame horses than in sound horses (phyaline cartilage was higher in lame horses than in sound horses. The MMP-2 amounts were significantly higher in tendons compared to other tissue types. Overall, 79% of the lame horses with lesions had MMP-9 in their tendons and the amount was higher than in sound horses (phyaline and fibrocartilage as well as the DDFT with potential implications for the pathogenesis and management of the condition.

  18. 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

  19. 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.

  20. Kinetic theory of tearing instability

    International Nuclear Information System (INIS)

    Hazeltine, R.D.; Dobrott, D.; Wang, T.S.

    1975-01-01

    The guiding-center kinetic equation with Fokker-Planck collision term is used to study, in cylindrical geometry, a class of dissipative instabilities of which the classical tearing mode is an archetype. Variational solution of the kinetic equation obviates the use of an approximate Ohm's law or adiabatic assumption, as used in previous studies, and it provides a dispersive relation which is uniformly valid for any ratio of wave frequency to collision frequency. One result of using the rigorous collision operator is the prediction of a new instability. This instability, driven by the electron temperature gradient, is predicted to occur under the long mean-free path conditions of present tokamak experiments, and has significant features in common with the kink-like oscillations observed in such experiments

  1. The combined use of kartogenin and platelet-rich plasma promotes fibrocartilage formation in the wounded rat Achilles tendon entheses.

    Science.gov (United States)

    Zhang, J; Yuan, T; Zheng, N; Zhou, Y; Hogan, M V; Wang, J H-C

    2017-04-01

    After an injury, the biological reattachment of tendon to bone is a challenge because healing takes place between a soft (tendon) and a hard (bone) tissue. Even after healing, the transition zone in the enthesis is not completely regenerated, making it susceptible to re-injury. In this study, we aimed to regenerate Achilles tendon entheses (ATEs) in wounded rats using a combination of kartogenin (KGN) and platelet-rich plasma (PRP). Wounds created in rat ATEs were given three different treatments: kartogenin platelet-rich plasma (KGN-PRP); PRP; or saline (control), followed by histological and immunochemical analyses, and mechanical testing of the rat ATEs after three months of healing. Histological analysis showed well organised arrangement of collagen fibres and proteoglycan formation in the wounded ATEs in the KGN-PRP group. Furthermore, immunohistochemical analysis revealed fibrocartilage formation in the KGN-PRP-treated ATEs, evidenced by the presence of both collagen I and II in the healed ATE. Larger positively stained collagen III areas were found in both PRP and saline groups than those in the KGN-PRP group. Chondrocyte-related genes, SOX9 and collagen II, and tenocyte-related genes, collagen I and scleraxis (SCX), were also upregulated by KGN-PRP. Moreover, mechanical testing results showed higher ultimate tensile strength in the KGN-PRP group than in the saline control group. In contrast, PRP treatment appeared to have healed the injured ATE but induced no apparent formation of fibrocartilage. The saline-treated group showed poor healing without fibrocartilage tissue formation in the ATEs. Our results show that injection of KGN-PRP induces fibrocartilage formation in the wounded rat ATEs. Hence, KGN-PRP may be a clinically relevant, biological approach to regenerate injured enthesis effectively. Cite this article: J. Zhang, T. Yuan, N. Zheng, Y. Zhou, M. V. Hogan, J. H-C. Wang. The combined use of kartogenin and platelet-rich plasma promotes

  2. Resistive wall tearing mode generated finite net electromagnetic torque in a static plasma

    International Nuclear Information System (INIS)

    Hao, G. Z.; Wang, A. K.; Xu, M.; Qu, H. P.; Peng, X. D.; Wang, Z. H.; Xu, J. Q.; Qiu, X. M.; Liu, Y. Q.

    2014-01-01

    The MARS-F code [Y. Q. Liu et al., Phys. Plasmas 7, 3681 (2000)] is applied to numerically investigate the effect of the plasma pressure on the tearing mode stability as well as the tearing mode-induced electromagnetic torque, in the presence of a resistive wall. The tearing mode with a complex eigenvalue, resulted from the favorable averaged curvature effect [A. H. Glasser et al., Phys. Fluids 18, 875 (1975)], leads to a re-distribution of the electromagnetic torque with multiple peaking in the immediate vicinity of the resistive layer. The multiple peaking is often caused by the sound wave resonances. In the presence of a resistive wall surrounding the plasma, a rotating tearing mode can generate a finite net electromagnetic torque acting on the static plasma column. Meanwhile, an equal but opposite torque is generated in the resistive wall, thus conserving the total momentum of the whole plasma-wall system. The direction of the net torque on the plasma is always opposite to the real frequency of the mode, agreeing with the analytic result by Pustovitov [Nucl. Fusion 47, 1583 (2007)]. When the wall time is close to the oscillating time of the tearing mode, the finite net torque reaches its maximum. Without wall or with an ideal wall, no net torque on the static plasma is generated by the tearing mode. However, re-distribution of the torque density in the resistive layer still occurs

  3. Glycomic characterization of basal tears and changes with diabetes and diabetic retinopathy.

    Science.gov (United States)

    Nguyen-Khuong, Terry; Everest-Dass, Arun V; Kautto, Liisa; Zhao, Zhenjun; Willcox, Mark D P; Packer, Nicolle H

    2015-03-01

    As a secreted fluid, the state of tear glycosylation is particularly important in the role of immunity of the ocular surface. Tears are a valuable source of non-invasive biomarkers for disease and there are continued efforts to characterize their components thoroughly. In this study, a small volume of basal tears (5 μL) was collected from healthy controls, patients with diabetes without retinopathy and patients with diabetes and retinopathy. The detailed N- and O-linked tear protein glycome was characterized and the relative abundance of each structure determined. Of the 50 N-linked glycans found, 89% were complex with 50% containing a bisecting N-acetylglucosamine, 65% containing a core fucose whilst 33% were sialylated. Of the 8 O-linked glycans detected, 3 were of cores 1 and 5 of core 2 type, with a majority of them being sialylated (90%). Additionally, these glycan structures were profiled across the three diabetic disease groups. Whilst the higher abundant structures did not alter across the three groups, only five low abundance N-linked glycans and 1 O-linked glycan did alter with the onset of diabetes mellitus and diabetic retinopathy (DR). These results suggest the conservation of glycan types on basal tear proteins between individuals and point to only small changes in glycan expression on the proteins in tears with the development of diabetes and DR. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Arthroscopic modified Mason-Allen technique for large U- or L-shaped rotator cuff tears.

    Science.gov (United States)

    Jung, Sung-Weon; Kim, Dong-Hee; Kang, Seung-Hoon; Lee, Ji-Heon

    2017-07-01

    While a conventional single- or double-row repair technique could be applied for repair of C-shaped tears, a different surgical strategy should be considered for repair of U- or L-shaped tears because they typically have complex patterns with anterior, posterior, or both mobile leaves. This study was performed to examine the outcomes of the modified Mason-Allen technique for footprint restoration in the treatment of large U- or L-shaped rotator cuff tears. Thirty-two patients who underwent an arthroscopic modified Mason-Allen technique for large U- or L-shaped rotator cuff tears between January 2012 and December 2013 were included in this study. Margin convergence was first performed to reduce the tear gap and tension, and then, an arthroscopic Mason-Allen technique was performed to restore the rotator cuff footprint in a side-to-end repair fashion. All patients were evaluated preoperatively and for a minimum of 2 years of follow-up with a visual analog scale (VAS) for pain, Constant score, and ultrasonography. There was significant improvement in all VAS and Constant scores compared with the preoperative values (P rotator cuff in our data. Overall satisfactory results were achieved in most patients, with the exception of those with severe fatty degeneration. An arthroscopic modified Mason-Allen technique could be an effective and reliable alternative for patients with large U- or L-shaped rotator cuff tears. Case Series, Therapeutic Level IV.

  5. Evaluation of commercial glucometer test strips for potential measurement of glucose in tears.

    Science.gov (United States)

    Cha, Kyoung Ha; Jensen, Gary C; Balijepalli, Anant S; Cohan, Bruce E; Meyerhoff, Mark E

    2014-02-04

    Tear glucose measurements have been suggested as a potential alternative to blood glucose monitoring for diabetic patients. While previous work has reported that there is a correlation between blood and tear glucose levels in humans, this link has not been thoroughly established and additional clinical studies are needed. Herein, we evaluate the potential of using commercial blood glucose test strips to measure glucose in tears. Of several blood glucose strips evaluated, only one brand exhibits the low detection limit required for quantitating glucose in tears. Calibration of these strips in the range of 0-100 μM glucose with an applied potential of 150 mV to the working electrode yields a sensitivity of 0.127 nA/μM and a limit of quantitation (LOQ) of 9 μM. The strips also exhibit ≤13% error (n = 3) for 25, 50, and 75 μM glucose in the presence of 10 μM acetaminophen, 100 μM ascorbic acid, and 100 μM uric acid. Measurements of glucose in tears from nine normal (nondiabetic) fasting human subjects using strips yielded glucose values within the range of 5-148 μM (mean = 47 μM, median = 43 μM), similar to those for human tears reported by others with more complex LC-MS methods. The glucometer strip method could facilitate more clinical studies to determine whether tear glucose and blood glucose levels sufficiently correlate for application to routine measurements in tears to supplement blood glucose testing. This would be especially helpful for children, adolescents, other Type 1 diabetics, and also for Type 2 diabetics who require treatment with insulin and cannot tolerate multiple finger sticks per day.

  6. Tear ferning in normal dogs and dogs with keratoconjunctivitis sicca ...

    African Journals Online (AJOL)

    This study evaluates tear ferning as an ancillary technique for the evaluation of the canine tear film in normal eyes and eyes affected by keratoconjunctivitis sicca (KCS). Thirty dogs with KCS and 50 control dogs with normal tear film were evaluated with a full ophthalmoscopic examination and a Schirmer tear test type 1 ...

  7. US detection of rotator cuff tear

    International Nuclear Information System (INIS)

    Soble, M.G.; Guay, R.C.; Kaye, A.D.

    1988-01-01

    Between June 1986 and April 1988, 75 patients suspected of having a tear of the rotator cuff underwent shoulder sonography and arthrography. Compared with anthrography, US demonstrated 92% of rotor cuff tears, with a specificity of 84% and a negative predictive value of 95%. In 30 patients who underwent surgery for a rotator cuff tear or other soft-tissue abnormality, sonography demonstrated a sensitivity of 93% and specificity of 73%, while arthrography demonstrated a sensitivity of 87% and specificity of 100%. The above data indicate that US is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury

  8. Adsorption of human tear lipocalin to human meibomian lipid films.

    Science.gov (United States)

    Millar, Thomas J; Mudgil, Poonam; Butovich, Igor A; Palaniappan, Chendur K

    2009-01-01

    Tear lipocalin (Tlc) is a major lipid binding protein in tears and is thought to have an important role in stabilizing the Meibomian lipid layer by transferring lipids to it from the aqueous layer or ocular surface, or by adsorbing to it directly. These possible roles have been investigated in vitro using human Tlc. Tlc was purified from human tears by size exclusion chromatography followed by ion exchange chromatography. Three additional samples of the Tlc were prepared by lipidation, delipidation, and relipidation. The lipids extracted from the purified Tlc were analyzed by HPLC-MS followed by fragmentation. Adsorption of these different forms of Tlc to a human Meibomian lipid film spread on the surface of an artificial tear buffer in a Langmuir trough were observed by recording changes in the pressure with time (Pi-T profile) and monitoring the appearance of the film microscopically. These results were compared with similar experiments using a bovine Meibomian lipid film. The results indicated that Tlc binds slowly to a human Meibomian lipid film compared with lysozyme or lactoferrin, even at 37 degrees C. The adsorption of Tlc to a human Meibomian lipid film was very different from its adsorption to a bovine Meibomian lipid film, indicating the nature of the lipids in the film is critical to the adsorption process. Similarly, the different forms of Tlc had quite distinct adsorption patterns, as indicated both by changes in Pi-T profiles and the microscopic appearance of the films. It was concluded that human Tlc was capable of adsorbing to and penetrating into a Meibomian lipid layer, but this process is very complex and depends on both the types of lipids bound to Tlc and the lipid complement comprising the Meibomian lipid film.

  9. Adsorption of Human Tear Lipocalin to Human Meibomian Lipid Films

    Science.gov (United States)

    Millar, Thomas J.; Mudgil, Poonam; Butovich, Igor A.; Palaniappan, Chendur K.

    2009-01-01

    Purpose Tear lipocalin (Tlc) is a major lipid binding protein in tears and is thought to have an important role in stabilizing the Meibomian lipid layer by transferring lipids to it from the aqueous layer or ocular surface, or by adsorbing to it directly. These possible roles have been investigated in vitro using human Tlc. Methods Tlc was purified from human tears by size exclusion chromatography followed by ion exchange chromatography. Three additional samples of the Tlc were prepared by lipidation, delipidation, and relipidation. The lipids extracted from the purified Tlc were analyzed by HPLC-MS followed by fragmentation. Adsorption of these different forms of Tlc to a human Meibomian lipid film spread on the surface of an artificial tear buffer in a Langmuir trough were observed by recording changes in the pressure with time (∏-T profile) and monitoring the appearance of the film microscopically. These results were compared with similar experiments using a bovine Meibomian lipid film. Results The results indicated that Tlc binds slowly to a human Meibomian lipid film compared with lysozyme or lactoferrin, even at 37°C. The adsorption of Tlc to a human Meibomian lipid film was very different from its adsorption to a bovine Meibomian lipid film, indicating the nature of the lipids in the film is critical to the adsorption process. Similarly, the different forms of Tlc had quite distinct adsorption patterns, as indicated both by changes in ∏-T profiles and the microscopic appearance of the films. Conclusions It was concluded that human Tlc was capable of adsorbing to and penetrating into a Meibomian lipid layer, but this process is very complex and depends on both the types of lipids bound to Tlc and the lipid complement comprising the Meibomian lipid film. PMID:18757516

  10. Role of ultrasound in rotator cuff tears

    International Nuclear Information System (INIS)

    Siddiqi, H.A.; Mirza, T.

    2010-01-01

    The study was designed to evaluate the efficacy of ultrasound in rotator cuff tears and to compare it with MRI. Total number of patients was thirty. All of these were above thirty years of age and were referred by clinicians, with shoulder pain for diagnostic workup. Post operative patients were excluded. Ultrasound and Magnetic Resonance Imaging (MRI) were performed on each patient. Same operator performed ultrasound in all patients. Ultrasound (US) and Magnetic Resonance Imaging (MRI) detected equal number of full thickness tears while two partial thickness tears were missed on US. Hypoechoic defect was the most important primary sign while cortical irregularity and fluid in subacromial and subdeltroid busra were the most important secondary signs on US. US was equally effective to MRI in detection of rotator cuff tears. It should be the primary investigation because of its availability, cost effective and real time evaluation provided significant expertise is developed, as it is highly operator dependent. (author)

  11. Influence of toroidal rotation on tearing modes

    Science.gov (United States)

    Cai, Huishan; Cao, Jintao; Li, Ding

    2017-10-01

    Tearing modes stability analysis including toroidal rotation is studied. It is found that rotation affects the stability of tearing modes mainly through the interaction with resistive inner region of tearing mode. The coupling of magnetic curvature with centrifugal force and Coriolis force provides a perturbed perpendicular current, and a return parallel current is induced to affect the stability of tearing modes. Toroidal rotation plays a stable role, which depends on the magnitude of Mach number and adiabatic index Γ, and is independent on the direction of toroidal rotation. For Γ >1, the scaling of growth rate is changed for typical Mach number in present tokamaks. For Γ = 1 , the scaling keeps unchanged, and the effect of toroidal rotation is much less significant, compared with that for Γ >1. National Magnetic Confinement Fusion Science Program and National Science Foundation of China under Grants No. 2014GB106004, No. 2013GB111000, No. 11375189, No. 11075161 and No. 11275260, and Youth Innovation Promotion Association CAS.

  12. An Athlete's Nightmare: Tearing the ACL

    Science.gov (United States)

    ... on the balls of their feet. "If the calf muscles are not absorbing the force, and if the knee is not in the proper position, the knee buckles and tears the ACL," explains Dr. Boden. After her initial ...

  13. Tearing mode analysis in tokamaks, revisited

    International Nuclear Information System (INIS)

    Nishimura, Y.; Callen, J.D.; Hegna, C.C.

    1997-12-01

    A new Δ' shooting code has been developed to investigate tokamak plasma tearing mode stability in a cylinder and large aspect ratio (ε ≤ 0.25) toroidal geometries, neglecting toroidal mode coupling. A different computational algorithm is used (shooting out from the singular surface instead of into it) to resolve the strong singularities at the mode rational surface, particularly in the presence of finite pressure term. Numerical results compare favorably with Furth et al. results. The effects of finite pressure, which are shown to decrease Δ', are discussed. It is shown that the distortion of the flux surfaces by the Shafranov shift, which modifies the geometry metric element stabilizes the tearing mode significantly, even in a low β regime before the toroidal magnetic curvature effects come into play. Double tearing modes in toroidal geometries are examined as well. Furthermore, m ≥ 2 tearing mode stability criteria are compared with three dimensional initial value MHD simulation by the FAR code

  14. 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.

  15. Ponderomotive modification of drift tearing modes

    International Nuclear Information System (INIS)

    Urquijo, G.; Singh, R.; Sen, A.

    1997-01-01

    The linear characteristics of drift tearing modes are investigated in the presence of a significant background of radio-frequency (RF) waves in the ion cyclotron range of frequencies. The ponderomotive force, arising from the radial gradients in the RF field energy, is found to significantly modify the inner layer solutions of the drift tearing modes. It can have a stabilizing influence, even at moderate RF powers, provided the field energy has a decreasing radial profile at the mode rational surface. (author)

  16. 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.

  17. Neoclassical tearing modes in a tokamak

    International Nuclear Information System (INIS)

    Hahm, T.S.

    1988-08-01

    Linear tearing instability is studied in the banana collisionality regime in tokamak geometry. Neoclassical effects produce significant modifications of Ohm's law and the vorticity equation so that the growth rate of tearing modes driven by Δ' is dramatically reduced compared to the usual resistive MHD value. Consequences of this result, regarding the presence of pressure-gradient-driven neoclassical resistive interchange instabilities and the evolution of magnetic islands in the Rutherford regime, are discussed. 10 refs

  18. Engineering Anisotropic Biomimetic Fibrocartilage Microenvironment by Bioprinting Mesenchymal Stem Cells in Nanoliter Gel Droplets

    Science.gov (United States)

    2015-01-01

    Over the past decade, bioprinting has emerged as a promising patterning strategy to organize cells and extracellular components both in two and three dimensions (2D and 3D) to engineer functional tissue mimicking constructs. So far, tissue printing has neither been used for 3D patterning of mesenchymal stem cells (MSCs) in multiphase growth factor embedded 3D hydrogels nor been investigated phenotypically in terms of simultaneous differentiation into different cell types within the same micropatterned 3D tissue constructs. Accordingly, we demonstrated a biochemical gradient by bioprinting nanoliter droplets encapsulating human MSCs, bone morphogenetic protein 2 (BMP-2), and transforming growth factor β1 (TGF- β1), engineering an anisotropic biomimetic fibrocartilage microenvironment. Assessment of the model tissue construct displayed multiphasic anisotropy of the incorporated biochemical factors after patterning. Quantitative real time polymerase chain reaction (qRT-PCR) results suggested genomic expression patterns leading to simultaneous differentiation of MSC populations into osteogenic and chondrogenic phenotype within the multiphasic construct, evidenced by upregulation of osteogenesis and condrogenesis related genes during in vitro culture. Comprehensive phenotypic network and pathway analysis results, which were based on genomic expression data, indicated activation of differentiation related mechanisms, via signaling pathways, including TGF, BMP, and vascular endothelial growth factor. PMID:24495169

  19. Engineering anisotropic biomimetic fibrocartilage microenvironment by bioprinting mesenchymal stem cells in nanoliter gel droplets.

    Science.gov (United States)

    Gurkan, Umut A; El Assal, Rami; Yildiz, Simin E; Sung, Yuree; Trachtenberg, Alexander J; Kuo, Winston P; Demirci, Utkan

    2014-07-07

    Over the past decade, bioprinting has emerged as a promising patterning strategy to organize cells and extracellular components both in two and three dimensions (2D and 3D) to engineer functional tissue mimicking constructs. So far, tissue printing has neither been used for 3D patterning of mesenchymal stem cells (MSCs) in multiphase growth factor embedded 3D hydrogels nor been investigated phenotypically in terms of simultaneous differentiation into different cell types within the same micropatterned 3D tissue constructs. Accordingly, we demonstrated a biochemical gradient by bioprinting nanoliter droplets encapsulating human MSCs, bone morphogenetic protein 2 (BMP-2), and transforming growth factor β1 (TGF- β1), engineering an anisotropic biomimetic fibrocartilage microenvironment. Assessment of the model tissue construct displayed multiphasic anisotropy of the incorporated biochemical factors after patterning. Quantitative real time polymerase chain reaction (qRT-PCR) results suggested genomic expression patterns leading to simultaneous differentiation of MSC populations into osteogenic and chondrogenic phenotype within the multiphasic construct, evidenced by upregulation of osteogenesis and condrogenesis related genes during in vitro culture. Comprehensive phenotypic network and pathway analysis results, which were based on genomic expression data, indicated activation of differentiation related mechanisms, via signaling pathways, including TGF, BMP, and vascular endothelial growth factor.

  20. 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)

  1. 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

  2. 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.

  3. Sonographic evaluation of digital annular pulley tears

    International Nuclear Information System (INIS)

    Martinoli, C.; Derchi, L.E.; Bianchi, S.; Garcia, J.F.; Nebiolo, M.

    2000-01-01

    Objective. To evaluate the sonographic (US) appearance of digital annular pulley (DAP) tears in high-level rock climbers. Design and patients. We performed a retrospective analysis of the US examinations of 16 high-level rock climbers with clinical signs of DAP lesions. MRI and surgical evaluation were performed in five and three patients respectively. The normal US and MRI appearances of DAP were evaluated in 40 and three normal fingers respectively. Results. Nine of 16 patients presented a DAP tear. In eight subjects (seven with complete tears involving the fourth finger and one the fifth finger), US diagnosis was based on the indirect sign of volar bowstringing of the flexor tendons. Injured pulleys were not appreciated by US. Tears concerned the A2 and A3 in six patients and the A3 and A4 in two patients. A2 pulley thickening and hypoechogenicity compatible with a partial tear was demonstrated in one patient. MRI and surgical data correlated well with the US findings. Four patients had tenosynovitis of the flexor tendons but no evidence of pulley disruption. US examinations of three patients were normal. In the healthy subjects US demonstrated DAP in 16 of 40 digits. Conclusion. US can diagnose DAP tears and correlates with the MRI and surgical data. Because of its low cost and non-invasiveness we suggest US as the first imaging modality in the evaluation of injuries of the digital pulley. (orig.)

  4. Sonographic evaluation of digital annular pulley tears

    Energy Technology Data Exchange (ETDEWEB)

    Martinoli, C.; Derchi, L.E. [Istituto di Radiologia, Universita di Genova, Genoa (Italy); Bianchi, S.; Garcia, J.F. [Dept. de Radiologie, Hopital Cantonal Universitaire de Geneve (Switzerland); Nebiolo, M. [Reparto Pronto Soccorso Medico, Pietra Ligure (Italy)

    2000-07-01

    Objective. To evaluate the sonographic (US) appearance of digital annular pulley (DAP) tears in high-level rock climbers. Design and patients. We performed a retrospective analysis of the US examinations of 16 high-level rock climbers with clinical signs of DAP lesions. MRI and surgical evaluation were performed in five and three patients respectively. The normal US and MRI appearances of DAP were evaluated in 40 and three normal fingers respectively. Results. Nine of 16 patients presented a DAP tear. In eight subjects (seven with complete tears involving the fourth finger and one the fifth finger), US diagnosis was based on the indirect sign of volar bowstringing of the flexor tendons. Injured pulleys were not appreciated by US. Tears concerned the A2 and A3 in six patients and the A3 and A4 in two patients. A2 pulley thickening and hypoechogenicity compatible with a partial tear was demonstrated in one patient. MRI and surgical data correlated well with the US findings. Four patients had tenosynovitis of the flexor tendons but no evidence of pulley disruption. US examinations of three patients were normal. In the healthy subjects US demonstrated DAP in 16 of 40 digits. Conclusion. US can diagnose DAP tears and correlates with the MRI and surgical data. Because of its low cost and non-invasiveness we suggest US as the first imaging modality in the evaluation of injuries of the digital pulley. (orig.)

  5. 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)

  6. Magnetic resonance findings in skeletal muscle tears

    International Nuclear Information System (INIS)

    De Smet, A.A.

    1993-01-01

    Magnetic resonance (MR) images of skeletal muscle tears can clearly delineate the severity of muscle injury. Although MR imaging is seldom necessary in patients with acute musle trauma, it can be helpful in deciding on clinical management. The two major MR findings in acute muscle tears are deformity of the muscle and the presence of abnormal signal reflecting hemorrhage and edema. In acute tears, methemoglobin within the extravascular blood causes high-signal areas on both T1- and T2-weighted images. With partial tears, the blood may dissect in a distinctive linear pattern along the muscle bundles and fibers. As healing begins, the muscle signal diminishes, first on the T1-weighted images and then on the T2-weighted images. When there is residual abnormal signal on images obtained more than several months after the injury, it is presumed to represent hemorrhage from recurrent tears. In patients with a questionable history of a remote injury, the clinical presentation may be that of persistent pain or a soft tissue mass. In these cases MR imaging may identify the cause of the pain and can exclude a neoplasm by proving that the mass is a hypertrophied or retracted musle. Thus, MR imaging has a limited, but occasionally important role in selected patients with skeletal muscle tears. (orig.)

  7. 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.

  8. Diet, nutraceuticals and the tear film.

    Science.gov (United States)

    Jalbert, Isabelle

    2013-12-01

    Nutrition disorders and their correlates such as obesity are increasingly prevalent worldwide. A number of studies to date have suggested numerous potential associations between diet and tear film health; this paper will provide a summary of the available literature. The tear film is characterized through its protein and lipid content and through clinical measurements of characteristics such as osmolarity, volume and stability. Malnutrition, protein and vitamin-A deficiencies are extremely deleterious to tear film health and supplementation with oral vitamin A in this setting is of clear benefit. The relative impact of diet on tear film within what would be considered normal ranges of consumption is less clear. A number of population studies have suggested that hyperlipidemia and a diet low in omega-3 fatty acids are risks factor for dry eye disease. Numerous studies have investigated the effectiveness of oral supplementation with antioxidants, omega-3 (e.g. fish oil and linseed oil) and omega-6 (e.g. evening primrose oil) fatty acids in the last 10 years. Taken together, these suggest a small benefit of oral supplementation on tear film volume, stability and decreased ocular symptoms in patients previously diagnosed with diseases involving the ocular surface (e.g. Sjögren's syndrome, meibomian gland dysfunction, dry eye disease) and contact lens wearers suffering from dry eye. More research is required to determine the exact composition, dosage and indications for their use and to fully characterize how these nutraceuticals modulate the tear film. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Influence of Structure and Composition on Dynamic Viscoelastic Property of Cartilaginous Tissue: Criteria for Classification between Hyaline Cartilage and Fibrocartilage Based on Mechanical Function

    Science.gov (United States)

    Miyata, Shogo; Tateishi, Tetsuya; Furukawa, Katsuko; Ushida, Takashi

    Recently, many types of methodologies have been developed to regenerate articular cartilage. It is important to assess whether the reconstructed cartilaginous tissue has the appropriate mechanical functions to qualify as hyaline (articular) cartilage. In some cases, the reconstructed tissue may become fibrocartilage and not hyaline cartilage. In this study, we determined the dynamic viscoelastic properties of these two types of cartilage by using compression and shear tests, respectively. Hyaline cartilage specimens were harvested from the articular surface of bovine knee joints and fibrocartilage specimens were harvested from the meniscus tissue of the same. The results of this study revealed that the compressive energy dissipation of hyaline cartilage showed a strong dependence on testing frequency at low frequencies, while that of fibrocartilage did not. Therefore, the compressive energy dissipation that is indicated by the loss tangent could become the criterion for the in vitro assessment of the mechanical function of regenerated cartilage.

  10. 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

  11. Magnetic tearing in plasma focus

    International Nuclear Information System (INIS)

    Sharkawy, W.

    1994-01-01

    A plasma focus device used is Mather type filled with hydrogen gas at pressure between 0.1 and 1 torr. When connected to a large capacitor ≤10 KV a discharge is started with peak current 100 KA. Under the influence of the radial electric field E r , due to the potential between electrodes, and B φ the plasma will drift in the axial direction with velocity cE r /B φ . An induced axial magnetic field B z has been detected which due to sheath velocity. A propagation of magnetosonic wave has been observed with velocity ≅10 3 m sec -1 . Such a wave might be excited when the magnetic pressure is much greater than the plasma kinetic pressure B 2 /8π>nKT. Assuming (MHD) to be stable, Tearing model was driven which generally has smaller growth rates than (MHD) modes. Using the designed theoretical model and the plasma parameters the electron energy dΦ/dt=Ba 2 /τ R was calculated to be 2.22 KeV, which is comparable with that detected from X-ray measurements. (author)

  12. Isolated tear of the tendon to the medial head of gastrocnemius presenting as a painless lump in the calf

    OpenAIRE

    Watura, Christopher; Harries, William

    2009-01-01

    We report on a case of isolated tear of the medial head of gastrocnemius tendon. The patient presented with a painless lump in the right calf and denied any prior history of trauma or strain to the leg. A longitudinal split of the tendon was demonstrated at ultrasound and magnetic resonance imaging (MRI). There were no other abnormalities and the gastrocnemius muscle was normal. There are no reports in the literature of isolated gastrocnemius tendon tear. To date the calf muscle complex injur...

  13. 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...

  14. Superior glenoid inclination and rotator cuff tears.

    Science.gov (United States)

    Chalmers, Peter N; Beck, Lindsay; Granger, Erin; Henninger, Heath; Tashjian, Robert Z

    2018-03-23

    The objectives of this study were to determine whether glenoid inclination (1) could be measured accurately on magnetic resonance imaging (MRI) using computed tomography (CT) as a gold standard, (2) could be measured reliably on MRI, and (3) whether it differed between patients with rotator cuff tears and age-matched controls without evidence of rotator cuff tears or glenohumeral osteoarthritis. In this comparative retrospective radiographic study, we measured glenoid inclination on T1 coronal MRI corrected into the plane of the scapula. We determined accuracy by comparison with CT and inter-rater reliability. We compared glenoid inclination between patients with full-thickness rotator cuff tears and patients aged >50 years without evidence of a rotator cuff tear or glenohumeral arthritis. An a priori power analysis determined adequate power to detect a 2° difference in glenoid inclination. (1) In a validation cohort of 37 patients with MRI and CT, the intraclass correlation coefficient was 0.877, with a mean difference of 0° (95% confidence interval, -1° to 1°). (2) For MRI inclination, the inter-rater intraclass correlation coefficient was 0.911. (3) Superior glenoid inclination was 2° higher (range, 1°-4°, P rotator cuff tear group of 192 patients than in the control cohort of 107 patients. Glenoid inclination can be accurately and reliably measured on MRI. Although superior glenoid inclination is statistically greater in those with rotator cuff tears than in patients of similar age without rotator cuff tears or glenohumeral arthritis, the difference is likely below clinical significance. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  15. Pulley lesions in rotator cuff tears: prevalence, etiology, and concomitant pathologies.

    Science.gov (United States)

    Hawi, Nael; Liodakis, Emmanouil; Garving, Christina; Habermeyer, Peter; Tauber, Mark

    2017-08-01

    This study aimed to demonstrate the prevalence of lesions in the biceps pulley complex in a representative, consecutive series of rotator cuff tears and rotator cuff interval treatments. We also analyzed associated tear pattern of rotator cuff injuries and superior labrum anterior-posterior (SLAP) lesions. We evaluated the relationships of these lesions to traumatic genesis and the prevalence of pulley lesions in revision cases. This retrospective study analyzed all pre- and intra-operative documentation on arthroscopic rotator cuff reconstructions and isolated pulley lesion treatments performed by a single surgeon over 2 consecutive years. According to Habermeyer et al., we classified cases into four groups, based on the presence of additional or related complete or partial rotator cuff tears, SLAP lesions, trauma, and primary or revision surgery. Among 382 patients with rotator cuff tears, 345 (90.3%) had an injured pulley system; 151 (43.8%) had partial tears of the rotator cuff; out of these, 106 (30.6%) were articular-sided. All of these articular-sided partial tears showed extension into the pulley complex. In 154 cases (44.6%), history of shoulder trauma was associated with the beginning of symptoms. In addition, concomitant SLAP lesions occurred in 25-62% of pulley lesions, correlating with the severity of pulley lesions. Among the 345 cases, there have been 32 (9.3%) revision cases where a pulley lesion was intra-operatively identified and addressed. Pulley complex lesions are present in 90.3% of surgically treated rotator cuff lesions, particularly in articular-sided injuries. In addition, we found a significant relationship between the incidence of SLAP lesions and the severity of pulley lesions. It seems reasonable to assume an important role of pulley system injuries in the pathogenesis of rotator cuff lesions.

  16. Energetic approach for ductile tearing

    International Nuclear Information System (INIS)

    Marie, St.

    1999-01-01

    This study focuses on ductile crack initiation and propagation. It aims to propose an approach for the engineer allowing the prediction of the evolution of cracks in large scale components, from parameters determined on laboratory specimens. A crack initiation criterion, defining a J i tenacity related to crack tip blunting proposed in the literature is validated in the study. This criterion is shown to be transferable from laboratory specimens to structures. The literature review shows that an approach based on the dissipated energy in the fracture process during propagation offers an economical and simple solution to simulate large crack growth. A numerical method is proposed to estimate this fracture energy. The existence of an energy parameter G fr is shown, by simulating the propagation by the simultaneous release of several elements and by the use of the Rice integral with an original integration path. This parameter represents the needed energy for a unit crack extension and appears to be intrinsic to the material. A global energy statement allows to relate this parameter to a variation of the plastic part of J integral. It offers a second numerical method to simulate the propagation just from stationary numerical calculations, as well as the elaboration of a simplified method. This approach, using two parameters J i and G fr , intrinsic to the material and experimentally measurable on specimens, is validated on many tests such as crack pipes subjected to four points bending and cracked rings in compression. For example, this approach allows to model up to 90 mm ductile tearing in a pipe with a circumferential through-wall crack in ferritic steel, or to anticipate the evolution of a semi-elliptical crack in an aged austenitic ferritic steel plate subjected to bending. (author)

  17. Rotator cuff tears: An evidence based approach

    Science.gov (United States)

    Sambandam, Senthil Nathan; Khanna, Vishesh; Gul, Arif; Mounasamy, Varatharaj

    2015-01-01

    Lesions of the rotator cuff (RC) are a common occurrence affecting millions of people across all parts of the globe. RC tears are also rampantly prevalent with an age-dependent increase in numbers. Other associated factors include a history of trauma, limb dominance, contralateral shoulder, smoking-status, hypercholesterolemia, posture and occupational dispositions. The challenge lies in early diagnosis since a high proportion of patients are asymptomatic. Pain and decreasing shoulder power and function should alert the heedful practitioner in recognizing promptly the onset or aggravation of existing RC tears. Partial-thickness tears (PTT) can be bursal-sided or articular-sided tears. Over the course of time, PTT enlarge and propagate into full-thickness tears (FTT) and develop distinct chronic pathological changes due to muscle retraction, fatty infiltration and muscle atrophy. These lead to a reduction in tendon elasticity and viability. Eventually, the glenohumeral joint experiences a series of degenerative alterations - cuff tear arthropathy. To avert this, a vigilant clinician must utilize and corroborate clinical skill and radiological findings to identify tear progression. Modern radio-diagnostic means of ultrasonography and magnetic resonance imaging provide excellent visualization of structural details and are crucial in determining further course of action for these patients. Physical therapy along with activity modifications, anti-inflammatory and analgesic medications form the pillars of nonoperative treatment. Elderly patients with minimal functional demands can be managed conservatively and reassessed at frequent intervals. Regular monitoring helps in isolating patients who require surgical interventions. Early surgery should be considered in younger, active and symptomatic, healthy patients. In addition to being cost-effective, this helps in providing a functional shoulder with a stable cuff. An easily reproducible technique of maximal strength and

  18. A case of recurrent bloody tears

    Directory of Open Access Journals (Sweden)

    Karslıoğlu Ş

    2011-07-01

    Full Text Available Şafak Karslioğlu1, Ilke Bahçeci Şimşek2, Müslime Akbaba11Ìstanbul Oculoplastic and Orbital Surgery and Ocular Oncology Center, 2Ophthalmology Department, Medicine Hospital, Ìstanbul, TurkeyAbstract: Well-known causes of blood-tinged epiphora are conjunctival lesions, tumors of the lacrimal apparatus, and systemic bleeding disorders. We describe an unusual patient who presented with recurrent episodes of bloody tearing which began following an erythema multiforme-like drug eruption. He experienced chronic conjunctivitis which resulted in a few minor symblephara. One year later, the patient developed attacks of bloody tearing. All clinical, radiologic, and laboratory investigations related to bloody epiphora were within normal limits except for a mild, nonspecific chronic inflammatory reaction in the perivascular tissues of the lacrimal gland and orbital soft tissues. Also, an increase in vascular permeability and contrast extravasation on carotid angiography was detected. High-dose vitamin C was administered. The patient continued to have unilateral bloody tears intermittently for two years, but the episodes became much less frequent and had resolved by three years. It is conceivable that increased vascular permeability following the systemic inflammatory process could have played a role in the etiology of recurrent bloody tears in this atypical patient.Keywords: bloody tears, erythema multiforme, drug eruption, vitamin C

  19. Allergy and allergic mediators in tears.

    Science.gov (United States)

    Leonardi, Andrea

    2013-12-01

    The identification of inflammatory mediators in the tear fluid have been extensively used in ocular allergy to find either a 'disease marker', to better understand the immune mechanisms involved in the ocular surface inflammation, or to identify potential targets for therapeutic interventions. While the clinical characteristics allow a relatively convincing diagnosis of ocular allergic diseases, in the initial, non active phases, or in the chronic stages, the diagnosis may not be clear. Although not highly specific, total tear IgE can be measured with local tests by inserting a paper strip in the lower meniscus. The measurement of tear specific inflammatory markers, such as histamine, tryptase, ECP, IL-4, IL-5 and eotaxin, may be useful for the diagnosis or monitoring ocular allergy. New technologies such as multiplex bead assays, membrane-bound antibody array and proteomic techniques can characterize the distribution of a wide range of bioactive trace proteins in tears. Dozens of mediators, cytokines, chemokines, growth factors, angiogenic modulators, enzymes and inhibitors were thus identified in small tear samples using these techniques, providing the possible identification of specific biomarker for either specific disease or disease activity. However, to date, there is no a single specific laboratory test suitable for the diagnosis and monitoring of allergic conjunctivitis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Effect of Strain, Region, and Tissue Composition on Glucose Partitioning in Meniscus Fibrocartilage.

    Science.gov (United States)

    Kleinhans, Kelsey L; Jackson, Alicia R

    2017-03-01

    A nearly avascular tissue, the knee meniscus relies on diffusive transport for nutritional supply to cells. Nutrient transport depends on solute partitioning in the tissue, which governs the amount of nutrients that can enter a tissue. The purpose of the present study was to investigate the effects of mechanical strain, tissue region, and tissue composition on the partition coefficient of glucose in meniscus fibrocartilage. A simple partitioning experiment was employed to measure glucose partitioning in porcine meniscus tissues from two regions (horn and central), from both meniscal components (medial and lateral), and at three levels of compression (0%, 10%, and 20%). Partition coefficient values were correlated to strain level, water volume fraction, and glycosaminoglycan (GAG) content of tissue specimens. Partition coefficient values ranged from 0.47 to 0.91 (n = 48). Results show that glucose partition coefficient is significantly (p < 0.001) affected by compression, decreasing with increasing strain. Furthermore, we did not find a statistically significant effect of tissue when comparing medial versus lateral (p = 0.181) or when comparing central and horn regions (p = 0.837). There were significant positive correlations between tissue water volume fraction and glucose partitioning for all groups. However, the correlation between GAG content and partitioning was only significant in the lateral horn group. Determining how glucose partitioning is affected by tissue composition and loading is necessary for understanding nutrient availability and related tissue health and/or degeneration. Therefore, this study is important for better understanding the transport and nutrition-related mechanisms of meniscal degeneration.

  1. The significance of calcified fibrocartilage on the cortical endplate of the translational sheep spine model.

    Science.gov (United States)

    Sinclair, Sarina K; Bell, Spencer; Epperson, Richard Tyler; Bloebaum, Roy D

    2013-05-01

    To gain an understanding of the vertebral cortical endplate and factors that may affect the ability to achieve skeletal attachment to intervertebral implants and fusion, this study aimed to characterize the hypermineralized tissue on the cortical endplate of the vertebral body on a commonly used animal model. Skeletally mature sheep were injected with tetracycline prior to euthanasia and the C2-C3, T5-T6, and L2-L3 spinal motion segments were excised and prepared. Vertebral tissues were imaged using backscatter electron (BSE) imaging, histology, and tetracycline labeling was used to assess bone remodeling within different tissue layers. It was determined that the hypermineralized tissue layer was calcified fibrocartilage (CFC). No tetracycline labels were identified in the CFC layer, in contrast to single and double labels that were present in the underlying bone, indicating the CFC present on the cortical endplate was not being actively remodeled. The average thickness of the CFC layer was 146.3 ± 70.53 µm in the cervical region, 98.2 ± 40.29 µm in the thoracic region, and 150.89 ± 69.25 µm in the lumbar region. This difference in thickness may be attributed to the regional biomechanical properties of the spine. Results from this investigation indicate the presence of a nonremodeling tissue on the cortical endplate of the vertebral body in sheep spines, which attaches the intervertebral disc to the vertebrae. This tissue, if not removed, would likely prevent successful bony attachment to an intervertebral device in spinal fusion studies and total disc replacement surgeries. Copyright © 2013 Wiley Periodicals, Inc.

  2. The effect of magnesium ion concentration on the fibrocartilage regeneration potential of goat costal chondrocytes.

    Science.gov (United States)

    Hagandora, Catherine K; Tudares, Mauro A; Almarza, Alejandro J

    2012-03-01

    Magnesium has recently been explored as a potential biomaterial for degradable orthopedic implants but its effect on fibrocartilage remains unknown. The objective of this study was to assess the effect of high concentrations of magnesium ions on the matrix production of goat costal fibrochondrocytes in vitro. Cells were cultured using a scaffoldless approach with media containing magnesium chloride (MgCl(2)) or magnesium sulfate (MgSO(4)) at concentrations of 20, 50, and 100 mM in addition to the baseline magnesium concentration of 0.8 mM MgSO(4). At 4 weeks, there were no significant differences in compressive tangent modulus and total matrix production between constructs cultured in 20 mM Mg(2+) and the 0.8 mM Mg(2+) control (435 ± 47 kPa). There was a significant decrease in compressive tangent modulus compared to the 0.8 mM Mg(2+) constructs in the 50 mM MgCl(2) and MgSO(4) groups, while the 100 mM groups were not mechanically testable (p < 0.05). The collagen and glycosaminoglycan (GAG) content of the 50 and 100 mM MgCl(2) and MgSO(4) constructs was significantly lower than the control (6.9 ± 0.5% and 16.5 ± 1.3% per dry weight, respectively) (p < 0.05). The results show that goat costal fibrochondrocytes exhibit a high degree of resiliency to magnesium ion concentrations up to 20 mM in vitro.

  3. Tearing modes induced by perpendicular electron cyclotron resonance heating in the KSTAR tokamak

    Science.gov (United States)

    Lee, H. H.; Lee, S. G.; Seol, J.; Aydemir, A. Y.; Bae, C.; Yoo, J. W.; Na, Y. S.; Kim, H. S.; Woo, M. H.; Kim, J.; Joung, M.; You, K. I.; Park, B. H.

    2014-10-01

    This paper reports on experimental evidence that shows perpendicular electron cyclotron resonance heating (ECRH) can trigger classical tearing modes when deposited near a rational flux surface. The complex evolution of an m = 2 island is followed during current ramp-up in KSTAR plasmas, from its initial onset as the rational surface enters the ECRH resonance layer to its eventual lock on the wall after the rational surface leaves the layer. Stability analysis coupled to a transport calculation of the current profile with ECRH shows that the perpendicular ECRH may play a significant role in triggering and destabilizing classical m = 2 tearing modes, in agreement with our experimental observation.

  4. Realistic Facial Expression of Virtual Human Based on Color, Sweat, and Tears Effects

    Directory of Open Access Journals (Sweden)

    Mohammed Hazim Alkawaz

    2014-01-01

    Full Text Available Generating extreme appearances such as scared awaiting sweating while happy fit for tears (cry and blushing (anger and happiness is the key issue in achieving the high quality facial animation. The effects of sweat, tears, and colors are integrated into a single animation model to create realistic facial expressions of 3D avatar. The physical properties of muscles, emotions, or the fluid properties with sweating and tears initiators are incorporated. The action units (AUs of facial action coding system are merged with autonomous AUs to create expressions including sadness, anger with blushing, happiness with blushing, and fear. Fluid effects such as sweat and tears are simulated using the particle system and smoothed-particle hydrodynamics (SPH methods which are combined with facial animation technique to produce complex facial expressions. The effects of oxygenation of the facial skin color appearance are measured using the pulse oximeter system and the 3D skin analyzer. The result shows that virtual human facial expression is enhanced by mimicking actual sweating and tears simulations for all extreme expressions. The proposed method has contribution towards the development of facial animation industry and game as well as computer graphics.

  5. Realistic facial expression of virtual human based on color, sweat, and tears effects.

    Science.gov (United States)

    Alkawaz, Mohammed Hazim; Basori, Ahmad Hoirul; Mohamad, Dzulkifli; Mohamed, Farhan

    2014-01-01

    Generating extreme appearances such as scared awaiting sweating while happy fit for tears (cry) and blushing (anger and happiness) is the key issue in achieving the high quality facial animation. The effects of sweat, tears, and colors are integrated into a single animation model to create realistic facial expressions of 3D avatar. The physical properties of muscles, emotions, or the fluid properties with sweating and tears initiators are incorporated. The action units (AUs) of facial action coding system are merged with autonomous AUs to create expressions including sadness, anger with blushing, happiness with blushing, and fear. Fluid effects such as sweat and tears are simulated using the particle system and smoothed-particle hydrodynamics (SPH) methods which are combined with facial animation technique to produce complex facial expressions. The effects of oxygenation of the facial skin color appearance are measured using the pulse oximeter system and the 3D skin analyzer. The result shows that virtual human facial expression is enhanced by mimicking actual sweating and tears simulations for all extreme expressions. The proposed method has contribution towards the development of facial animation industry and game as well as computer graphics.

  6. The effect of Meibomian lipids and tear proteins on evaporation rate under controlled in vitro conditions.

    Science.gov (United States)

    Herok, George Henryk; Mudgil, Poonam; Millar, Thomas James

    2009-07-01

    The lipid layer of the tear film is associated with preventing evaporative loss. The ability of human Meibomian lipids to reduce evaporation in vitro was tested. Films of human or animal Meibomian lipids or mixtures of cholesterol and phosphatidylcholine were spread on the surface of either artificial buffer or on whole tears and placed on a mass balance that was enclosed in a sealed chamber. The temperature was adjusted to 37 degrees C and gas flow was controlled. Increasing the amounts of Meibomian lipids gave a very small reduction in evaporation. It was concluded from these in vitro experiments that prevention of evaporation from the tear film is not due to the Meibomian lipids alone, but is more likely to be due to a complex interaction between components of the aqueous and the Meibomian lipids.

  7. Interplay among solidification, microstructure, residual strain and hot tearing in B206 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    D’Elia, F., E-mail: f.delia10@gmail.com [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard St. East, Toronto, Ontario, Canada M5B 2K3 (Canada); Ravindran, C. [Centre for Near-net-shape Processing of Materials, Ryerson University, 101 Gerrard St. East, Toronto, Ontario, Canada M5B 2K3 (Canada); Sediako, D. [Canadian Neutron Beam Centre, Chalk River Laboratories, Chalk River, Ontario, Canada K0J 1J0 (Canada)

    2015-01-29

    Hot tearing is a complex phenomenon attributed to alloy solidification, microstructure and stress/strain development within a casting. In this research, the conditions associated with the formation of hot tears in B206 aluminum alloy were investigated. Neutron diffraction strain mapping was carried out on three B206 castings with varying levels of titanium (i.e. unrefined, 0.02 and 0.05 wt%). Titanium additions effectively reduced grain size and transformed grain morphology from coarse dendrites to fine globular grains. Further, thermal analysis suggested that grain refinement delayed the onset of dendrite coherency in B206 and therefore enhanced the duration of bulk liquid metal feeding for the refined casting conditions. As a result, the interactive effects of such factors resulted in a more uniform distribution of strain, and subsequent higher resistance to hot tearing for the grain refined castings.

  8. Clinical results of arthroscopic polyglycolic acid sheet patch graft for irreparable rotator cuff tears

    Directory of Open Access Journals (Sweden)

    Yu Mochizuki

    2015-01-01

    Full Text Available The high retear rates after surgery for irreparable rotator cuff tears can be explained by the healing capacity potential of tendons and the native rotator cuff enthesis characterised by complex morphological structures, called direct insertion. Many experimental researches have focused on biologically augmenting the rotator cuff reconstruction and improving tendon–bone healing of the rotator cuff. The results of the experimental study showed that the polyglycolic acid sheet scaffold material allows for the regeneration of not only tendon-to-tendon, but also tendon-to-bone interface in an animal model. We performed a clinical study of the arthroscopic polyglycolic acid sheet patch graft used for the repair of irreparable rotator cuff tears. One-year clinical results of the repair of irreparable rotator cuff tears by arthroscopic patch graft with a polyglycolic acid sheet demonstrated improved shoulder function and a significantly lower retear rate, compared with patients treated with a fascia lata patch.

  9. 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

  10. Isolated tear of the tendon to the medial head of gastrocnemius presenting as a painless lump in the calf.

    Science.gov (United States)

    Watura, Christopher; Harries, William

    2009-01-01

    We report on a case of isolated tear of the medial head of gastrocnemius tendon. The patient presented with a painless lump in the right calf and denied any prior history of trauma or strain to the leg. A longitudinal split of the tendon was demonstrated at ultrasound and magnetic resonance imaging (MRI). There were no other abnormalities and the gastrocnemius muscle was normal. There are no reports in the literature of isolated gastrocnemius tendon tear. To date the calf muscle complex injury described in this area is tearing of the medial head of gastrocnemius muscle, sometimes referred to as "tennis leg". We conclude that an isolated tear of the tendon to the medial head of gastrocnemius should be considered in the differential diagnosis of a lump or swelling in the upper medial area of the calf and we recommend ultrasound or MRI as the investigations of choice.

  11. Plate Tearing Under Mixed Mode Loading

    DEFF Research Database (Denmark)

    Andersen, Rasmus Grau; Nielsen, Kim Lau; Felter, Christian Lotz

    2016-01-01

    the mesh cannot accurately capture the localization process that precedes ductile failure. To fertilize accurate predictions of such sheet tearing, the energy dissipated during localization must, therefore, be accounted for in the cohesive traction-separation law. The fact is that the local thinning...... that takes place in front of an advancing crack can significantly enhance the crack growth resistanceas the energy going into thinning the sheet typically dominates the total fracture energy.This has been investigated in great details for the case of pure Mode I tearing and both the energy dissipation, peak...... stress, and shape of the cohesive traction-separation law have been laid out. In a similar fashion, the present study resolves the sequence of failure details related to steady-state sheet tearing under mixed mode loading by employing the micro-mechanics based Gurson model. But, the fracture process...

  12. Slab tears and intermediate-depth seismicity

    Science.gov (United States)

    Meighan, Hallie E.; ten Brink, Uri S.; Pulliam, Jay

    2013-01-01

    Active tectonic regions where plate boundaries transition from subduction to strike slip can take several forms, such as triple junctions, acute, and obtuse corners. Well-documented slab tears that are associated with high rates of intermediate-depth seismicity are considered here: Gibraltar arc, the southern and northern ends of the Lesser Antilles arc, and the northern end of Tonga trench. Seismicity at each of these locations occurs, at times, in the form of swarms or clusters, and various authors have proposed that each marks an active locus of tear propagation. The swarms and clusters start at the top of the slab below the asthenospheric wedge and extend 30–60 km vertically downward within the slab. We propose that these swarms and clusters are generated by fluid-related embrittlement of mantle rocks. Focal mechanisms of these swarms generally fit the shear motion that is thought to be associated with the tearing process.

  13. Bilateral Giant Retinal Tear and Sequential Vitrectomy.

    Science.gov (United States)

    Mustapha, Mushawiahti; Roufail Franzco, Edward

    2017-01-01

    To describe the excellent outcome of surgery for bilateral giant retinal tears (GRTs) with better options of endotamponade. This is a case report of a 62-year-old man who presented with bilateral GRTs and associated retinal detachment. The tear in the right eye was supero-temporal and silicone oil was used as an endotamponade. The tear in the left eye was infero-temporal and perfluorocarbon liquid was used as an endotamponade. The outcome at 6 months after surgery was excellent with visual acuities of 6/6 in both eyes. Improved availability of endotamponade agents allows repair of bilateral GRTs to be done at the same time, with good surgical outcomes.

  14. Rotator cuff tear measurement by arthropneumotomography

    International Nuclear Information System (INIS)

    Kilcoyne, R.F.; Matsen, F.A. III

    1983-01-01

    Five years of experience with a method of shoulder arthrography using upright tomography in cases of suspected or known rotator cuff tears has demonstrated its effectiveness. The value of the procedure lies in its ability to demonstrate the size of the cuff tear and the thickness of the remaining cuff tissue. This information provides the surgeon with a preoperative estimate of the difficulty of the repair and the prognosis for a good functional recovery. In 33 cases, there was good correlation between the upright thin-section tomogram findings and the surgical results. The tomograms provided better information about the size of the tear and the quality of the remaining cuff than did plain arthrograms

  15. 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

  16. Introduction to the linear theory of tearing instabilities

    International Nuclear Information System (INIS)

    Hazeltine, R.D.

    1978-02-01

    The reasons why tearing instabilities might bear importantly on tokamak performance are considered. The mechanism of tearing is described and the method by which this mechanism is analyzed is outlined. A survey is given of typical growth rate predictions

  17. Superior labrum anterior-to-posterior tear.

    Science.gov (United States)

    Sum, Jonathan C; Omid, Reza

    2012-12-01

    The patient was a 25-year-old male college student with a chief complaint of right shoulder pain. The patient was initially diagnosed with bicipital tendinitis by his physician and had been treated for 4 weeks by a physical therapist. However, his symptoms did not improve and he was unable to return to his preinjury activity levels, so he sought the services of another physical therapist for a second opinion. Due to concern for a labrum tear, the physical therapist referred the patient to an orthopaedic surgeon. Magnetic resonance arthrography revealed findings consistent with a superior labrum anterior-to-posterior tear.

  18. 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

  19. Endochondral fracture healing with external fixation in the Sost knockout mouse results in earlier fibrocartilage callus removal and increased bone volume fraction and strength.

    Science.gov (United States)

    Morse, A; Yu, N Y C; Peacock, L; Mikulec, K; Kramer, I; Kneissel, M; McDonald, M M; Little, D G

    2015-02-01

    Sclerostin deficiency, via genetic knockout or anti-Sclerostin antibody treatment, has been shown to cause increased bone volume, density and strength of calluses following endochondral bone healing. However, there is limited data on the effect of Sclerostin deficiency on the formative early stage of fibrocartilage (non-bony tissue) formation and removal. In this study we extensively investigate the early fibrocartilage callus. Closed tibial fractures were performed on Sost(-/-) mice and age-matched wild type (C57Bl/6J) controls and assessed at multiple early time points (7, 10 and 14days), as well as at 28days post-fracture after bony union. External fixation was utilized, avoiding internal pinning and minimizing differences in stability stiffness, a variable that has confounded previous research in this area. Normal endochondral ossification progressed in wild type and Sost(-/-) mice with equivalent volumes of fibrocartilage formed at early day 7 and day 10 time points, and bony union in both genotypes by day 28. There were no significant differences in rate of bony union; however there were significant increases in fibrocartilage removal from the Sost(-/-) fracture calluses at day 14 suggesting earlier progression of endochondral healing. Earlier bone formation was seen in Sost(-/-) calluses over wild type with greater bone volume at day 10 (221%, p<0.01). The resultant Sost(-/-) united bony calluses at day 28 had increased bone volume fraction compared to wild type calluses (24%, p<0.05), and the strength of the fractured Sost(-/-) tibiae was greater than that that of wild type fractured tibiae. In summary, bony union was not altered by Sclerostin deficiency in externally-fixed closed tibial fractures, but fibrocartilage removal was enhanced and the resultant united bony calluses had increased bone fraction and increased strength. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  20. A chondroitinase-ABC and TGF-β1 treatment regimen for enhancing the mechanical properties of tissue-engineered fibrocartilage.

    Science.gov (United States)

    MacBarb, Regina F; Makris, Eleftherios A; Hu, Jerry C; Athanasiou, Kyriacos A

    2013-01-01

    The development of functionally equivalent fibrocartilage remains elusive despite efforts to engineer tissues such as knee meniscus, intervertebral disc and temporomandibular joint disc. Attempts to engineer these structures often fail to create tissues with mechanical properties on a par with native tissue, resulting in constructs unsuitable for clinical applications. The objective of this study was to engineer a spectrum of biomimetic fibrocartilages representative of the distinct functional properties found in native tissues. Using the self-assembly process, different co-cultures of meniscus cells and articular chondrocytes were seeded into agarose wells and treated with the catabolic agent chondroitinase-ABC (C-ABC) and the anabolic agent transforming growth factor-β1 (TGF-β1) via a two-factor (cell ratio and bioactive treatment), full factorial study design. Application of both C-ABC and TGF-β1 resulted in a beneficial or positive increase in the collagen content of treated constructs compared to controls. Significant increases in both the collagen density and fiber diameter were also seen with this treatment, increasing these values by 32 and 15%, respectively, over control values. Mechanical testing found the combined bioactive treatment to synergistically increase the Young's modulus and ultimate tensile strength of the engineered fibrocartilages compared to controls, with values reaching the lower spectrum of those found in native tissues. Together, these data demonstrate that C-ABC and TGF-β1 interact to develop a denser collagen matrix better able to withstand tensile loading. This study highlights a way to optimize the tensile properties of engineered fibrocartilage using a biochemical and a biophysical agent together to create distinct fibrocartilages with functional properties mimicking those of native tissue. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. 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.

  2. 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.

  3. Quasi-linear evolution of tearing modes

    International Nuclear Information System (INIS)

    Pellat, R.; Frey, M.; Tagger, M.

    1983-07-01

    The growth of a Tearing instability in Rutherford's nonlinear regime is investigated. Using a singular perturbation technique, lowest order Rutherford's result is recovered. To the following order it is shown that the mode generates a quasi-linear deformation of the equilibrium flux profile, whose resistive diffusion slows down the growth and shows the possibility of a saturation of the instability

  4. Simulation of saturated tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Nguyen, Canh N.; Bateman, Glenn; Kritz, Arnold H.

    2004-01-01

    A quasi-linear model, which includes the effect of the neoclassical bootstrap current, is developed for saturated tearing modes in order to compute magnetic island widths in axisymmetric toroidal plasmas with arbitrary aspect ratio and cross-sectional shape. The model is tested in a simple stand-alone code and is implemented in the BALDUR [C. E. Singer et al., Comput. Phys. Commun. 49, 275 (1982)] predictive modeling code. It is found that the widths of tearing mode islands increase with decreasing aspect ratio and with increasing elongation. Also, the island widths increase when the gradient of the current density increases at the edge of the islands and when the current density inside the islands is suppressed, such as the suppression caused by the near absence of the bootstrap current within the islands. In simulations of tokamak discharges, it is found that tearing mode island widths oscillate in time in response to periodic sawtooth crashes. The local enhancements in the transport produced by magnetic islands have a noticeable effect on global plasma confinement in simulations of low aspect ratio, high beta tokamaks, where saturated tearing mode islands can occur with widths that are greater than 15% of the plasma minor radius

  5. Treatment for acute anterior cruciate ligament tear

    DEFF Research Database (Denmark)

    Frobell, Richard B; Roos, Harald P; Roos, Ewa M

    2013-01-01

    To compare, in young active adults with an acute anterior cruciate ligament (ACL) tear, the mid-term (five year) patient reported and radiographic outcomes between those treated with rehabilitation plus early ACL reconstruction and those treated with rehabilitation and optional delayed ACL...

  6. Glenohumeral stability in simulated rotator cuff tears

    NARCIS (Netherlands)

    Steenbrink, F.; Groot, J.H.; Veeger, H.E.J.; Helm, F.C.; Rozing, P.M.

    2009-01-01

    Rotator cuff tears disrupt the force balance in the shoulder and the glenohumeral joint in particular, resulting in compromised arm elevation torques. The trade-off between glenohumeral torque and glenohumeral stability is not yet understood. We hypothesize that compensation of lost abduction torque

  7. Acute compartment syndrome after medial gastrocnemius tear.

    Science.gov (United States)

    Sit, Yan Kit; Lui, Tun Hing

    2015-02-01

    Acute compartment syndrome after medial gastrocnemius tear is very rare. It can involve the superficial posterior compartment alone or progress to involve all the 4 compartments of the lower legs. Those patients with high pain tolerance and minor trauma can lead to delayed presentation. Immediate fasciotomy is the treatment of choice. Therapeutic Level IV, Case Study. © 2014 The Author(s).

  8. 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.

  9. 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

  10. 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

  11. The Tear Osmolarity Changes After Cataract Surgery

    Directory of Open Access Journals (Sweden)

    Banu Öncel

    2012-01-01

    Full Text Available Pur po se: To determine the tear osmolarity changes in patients who had undergone phacoemulsification surgery. Ma te ri al and Met hod: Tear osmolarity measurements were performed in 30 eyes of 30 patients who had undergone cataract surgery without any complication. Measurements were performed before surgery and consecutively at 1st month, 3rd month, and 6th month after the surgery. TearLab osmometer (TearLab Corporation, San Diego, CA, USA device was used for the measurements and paired ttest was used for statistical analysis. Re sults: The mean age of the patients was 72.3±3.7 (67-78 years. Thirteen patients were men and 17 patients were women. The mean osmolarity values were 305.8±6.5 mOsm/L before the surgery and 312.3±6.4 mOsm/L at 1st month, 307.5±5.1 mOsm/L at 3rd month and 305.1±5.7 at 6th month after the surgery. The difference between the values before surgery and at 1st month was found statistically significant (p=0.001. Dis cus si on: The tear osmolarity increases at the first month after surgery but decreases to the levels measured before surgery at the 3rd month. The increase at the first month may be due to the corneal incisions and medication used after the surgery. We think that we have to take into account this similarity increase in all cataract patients, especially in those who also have dry eye disease. (Turk J Ophthalmol 2012; 42: 35-7

  12. Oxidative stress induced inflammation initiates functional decline of tear production.

    Directory of Open Access Journals (Sweden)

    Yuichi Uchino

    Full Text Available Oxidative damage and inflammation are proposed to be involved in an age-related functional decline of exocrine glands. However, the molecular mechanism of how oxidative stress affects the secretory function of exocrine glands is unclear. We developed a novel mev-1 conditional transgenic mouse model (Tet-mev-1 using a modified tetracycline system (Tet-On/Off system. This mouse model demonstrated decreased tear production with morphological changes including leukocytic infiltration and fibrosis. We found that the mev-1 gene encodes Cyt-1, which is the cytochrome b(560 large subunit of succinate-ubiquinone oxidoreductase in complex II of mitochondria (homologous to succinate dehydrogenase C subunit (SDHC in humans. The mev-1 gene induced excessive oxidative stress associated with ocular surface epithelial damage and a decrease in protein and aqueous secretory function. This new model provides evidence that mitochondrial oxidative damage in the lacrimal gland induces lacrimal dysfunction resulting in dry eye disease. Tear volume in Tet-mev-1 mice was lower than in wild type mice and histopathological analyses showed the hallmarks of lacrimal gland inflammation by intense mononuclear leukocytic infiltration and fibrosis in the lacrimal gland of Tet-mev-1 mice. These findings strongly suggest that oxidative stress can be a causative factor for the development of dry eye disease.

  13. 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.)

  14. [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.

  15. 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)

  16. Dysfunctional tear syndrome: dry eye disease and associated tear film disorders – new strategies for diagnosis and treatment

    Science.gov (United States)

    Milner, Mark S.; Beckman, Kenneth A.; Luchs, Jodi I.; Allen, Quentin B.; Awdeh, Richard M.; Berdahl, John; Boland, Thomas S.; Buznego, Carlos; Gira, Joseph P.; Goldberg, Damien F.; Goldman, David; Goyal, Raj K.; Jackson, Mitchell A.; Katz, James; Kim, Terry; Majmudar, Parag A.; Malhotra, Ranjan P.; McDonald, Marguerite B.; Rajpal, Rajesh K.; Raviv, Tal; Rowen, Sheri; Shamie, Neda; Solomon, Jonathan D.; Stonecipher, Karl; Tauber, Shachar; Trattler, William; Walter, Keith A.; Waring, George O.; Weinstock, Robert J.; Wiley, William F.; Yeu, Elizabeth

    2017-01-01

    Dysfunctional tear syndrome (DTS) is a common and complex condition affecting the ocular surface. The health and normal functioning of the ocular surface is dependent on a stable and sufficient tear film. Clinician awareness of conditions affecting the ocular surface has increased in recent years because of expanded research and the publication of diagnosis and treatment guidelines pertaining to disorders resulting in DTS, including the Delphi panel treatment recommendations for DTS (2006), the International Dry Eye Workshop (DEWS) (2007), the Meibomian Gland Dysfunction (MGD) Workshop (2011), and the updated Preferred Practice Pattern guidelines from the American Academy of Ophthalmology pertaining to dry eye and blepharitis (2013). Since the publication of the existing guidelines, new diagnostic techniques and treatment options that provide an opportunity for better management of patients have become available. Clinicians are now able to access a wealth of information that can help them obtain a differential diagnosis and treatment approach for patients presenting with DTS. This review provides a practical and directed approach to the diagnosis and treatment of patients with DTS, emphasizing treatment that is tailored to the specific disease subtype as well as the severity of the condition. PMID:28099212

  17. Dysfunctional tear syndrome: dry eye disease and associated tear film disorders - new strategies for diagnosis and treatment.

    Science.gov (United States)

    Milner, Mark S; Beckman, Kenneth A; Luchs, Jodi I; Allen, Quentin B; Awdeh, Richard M; Berdahl, John; Boland, Thomas S; Buznego, Carlos; Gira, Joseph P; Goldberg, Damien F; Goldman, David; Goyal, Raj K; Jackson, Mitchell A; Katz, James; Kim, Terry; Majmudar, Parag A; Malhotra, Ranjan P; McDonald, Marguerite B; Rajpal, Rajesh K; Raviv, Tal; Rowen, Sheri; Shamie, Neda; Solomon, Jonathan D; Stonecipher, Karl; Tauber, Shachar; Trattler, William; Walter, Keith A; Waring, George O; Weinstock, Robert J; Wiley, William F; Yeu, Elizabeth

    2017-01-01

    Dysfunctional tear syndrome (DTS) is a common and complex condition affecting the ocular surface. The health and normal functioning of the ocular surface is dependent on a stable and sufficient tear film. Clinician awareness of conditions affecting the ocular surface has increased in recent years because of expanded research and the publication of diagnosis and treatment guidelines pertaining to disorders resulting in DTS, including the Delphi panel treatment recommendations for DTS (2006), the International Dry Eye Workshop (DEWS) (2007), the Meibomian Gland Dysfunction (MGD) Workshop (2011), and the updated Preferred Practice Pattern guidelines from the American Academy of Ophthalmology pertaining to dry eye and blepharitis (2013). Since the publication of the existing guidelines, new diagnostic techniques and treatment options that provide an opportunity for better management of patients have become available. Clinicians are now able to access a wealth of information that can help them obtain a differential diagnosis and treatment approach for patients presenting with DTS. This review provides a practical and directed approach to the diagnosis and treatment of patients with DTS, emphasizing treatment that is tailored to the specific disease subtype as well as the severity of the condition.

  18. 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.

  19. Lineage plasticity and cell biology of fibrocartilage and hyaline cartilage: Its significance in cartilage repair and replacement

    International Nuclear Information System (INIS)

    Freemont, Anthony J.; Hoyland, Judith

    2006-01-01

    Cartilage repair is a major goal of modern tissue engineering. To produce novel engineered implants requires a knowledge of the basic biology of the tissues that are to be replaced or reproduced. Hyaline articular cartilage and meniscal fibrocartilage are two tissues that have excited attention because of the frequency with which they are damaged. A basic strategy is to re-engineer these tissues ex vivo by stimulating stem cells to differentiate into the cells of the mature tissue capable of producing an intact functional matrix. In this brief review, the sources of cells for tissue engineering cartilage and the culture conditions that have promoted differentiation are discussed within the context of natural cartilage repair. In particular, the role of cell density, cytokines, load, matrices and oxygen tension are discussed

  20. Lineage plasticity and cell biology of fibrocartilage and hyaline cartilage: Its significance in cartilage repair and replacement

    Energy Technology Data Exchange (ETDEWEB)

    Freemont, Anthony J. [Regenerative Medicine Research Group, University of Manchester, England (United Kingdom)]. E-mail: Tony.freemont@man.ac.uk; Hoyland, Judith [Regenerative Medicine Research Group, University of Manchester, England (United Kingdom)

    2006-01-15

    Cartilage repair is a major goal of modern tissue engineering. To produce novel engineered implants requires a knowledge of the basic biology of the tissues that are to be replaced or reproduced. Hyaline articular cartilage and meniscal fibrocartilage are two tissues that have excited attention because of the frequency with which they are damaged. A basic strategy is to re-engineer these tissues ex vivo by stimulating stem cells to differentiate into the cells of the mature tissue capable of producing an intact functional matrix. In this brief review, the sources of cells for tissue engineering cartilage and the culture conditions that have promoted differentiation are discussed within the context of natural cartilage repair. In particular, the role of cell density, cytokines, load, matrices and oxygen tension are discussed.

  1. A Novel Technique of Rescuing Capsulorhexis Radial Tear-out using a Cystotome

    Science.gov (United States)

    Miah, Mizanur R.; Sleep, Tamsin; Hanifudin, Abdul

    2011-01-01

    Part 1 : Purpose: To demonstrate a capsulorhexis radial tear out rescue technique using a cystotome on a virtual reality cataract surgery simulator and in a human eye. Part 2 : Method: Steps: When a capsulorhexis begins to veer radially towards the periphery beyond the pupillary margin the following steps should be applied without delay. 2.1) Stop further capsulorhexis manoeuvre and reassess the situation. 2.2) Fill the anterior chamber with ophthalmic viscosurgical device (OVD). We recommend mounting the cystotome to a syringe containing OVD so that the anterior chamber can be reinflated rapidly. 2.3) The capsulorhexis flap is then left unfolded on the lens surface. 2.4) The cystotome tip is tilted horizontally to avoid cutting or puncturing the flap and is engaged on the flap near the leading edge of the tear but not too close to the point of tear. 2.5) Gently push or pull the leading edge of tear opposite to the direction of tear. 2.6) The leading tearing edge will start to do a 'U-Turn'. Maintain the tension on the flap until the tearing edge returns to the desired trajectory. Part 3 : Results: Using our technique, a surgeon can respond instantly to radial tear out without having to change surgical instruments. Changing surgical instruments at this critical stage runs a risk of further radial tear due to sudden shallowing of anterior chamber as a result of forward pressure from the vitreous. Our technique also has the advantage of reducing corneal wound distortion and subsequent anterior chamber collapse. Part 4 : Discussion The EYESI Surgical Simulator is a realistic training platform for surgeons to practice complex capsulorhexis tear-out techniques. Capsulorhexis is the most important and complex part of phacoemulsification and endocapsular intraocular lens implantation procedure. A successful cataract surgery depends on achieving a good capsulorhexis. During capsulorhexis, surgeons may face a challenging situation like a capsulorhexis radial tear-out. A

  2. Tear dysfunction and the cornea: LXVIII Edward Jackson Memorial Lecture.

    Science.gov (United States)

    Pflugfelder, Stephen C

    2011-12-01

    To describe the cause and consequence of tear dysfunction-related corneal disease. Perspective on effects of tear dysfunction on the cornea. Evidence is presented on the effects of tear dysfunction on corneal morphology, function, and health, as well as efficacy of therapies for tear dysfunction-related corneal disease. Tear dysfunction is a prevalent eye disease and the most frequent cause for superficial corneal epithelial disease that results in corneal barrier disruption, an irregular optical surface, light scattering, optical aberrations, and exposure and sensitization of pain-sensing nerve endings (nociceptors). Tear dysfunction-related corneal disease causes irritation and visual symptoms such as photophobia and blurred and fluctuating vision that may decrease quality of life. Dysfunction of 1 or more components of the lacrimal functional unit results in changes in tear composition, including elevated osmolarity and increased concentrations of matrix metalloproteinases, inflammatory cytokines, and chemokines. These tear compositional changes promote disruption of tight junctions, alter differentiation, and accelerate death of corneal epithelial cells. Corneal epithelial disease resulting from tear dysfunction causes eye irritation and decreases visual function. Clinical and basic research has improved understanding of the pathogenesis of tear dysfunction-related corneal epithelial disease, as well as treatment outcomes. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. 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.

  4. Treatment of the subject of tearing instability

    International Nuclear Information System (INIS)

    Paris, P.C.

    1977-07-01

    A simple approach is taken to the mechanics of potential instability associated with the steady tearing portion of J-Integral R-curves. The analysis is developed from simple examples of structural component (or test specimen) configurations with cracks, examining their instability possibilities individually, in order to draw more general conclusions about elastic-plastic cracking instability as contrasted to linear-elastic behavior. Finally, an attempt is made to model a more local cleavage-like instability for material in the fracture process zone just ahead of a crack tip. Results are then presented of a testing program which clearly demonstrates the appropriateness of the tearing instability analysis and which illustrates its broad potential for future application, as well as presenting guidelines for its further development. The material selected for analysis was Ni-Cr-Mo-V rotor steel

  5. Saturated tearing modes in tokamaks with divertors

    International Nuclear Information System (INIS)

    Bateman, G.

    1982-12-01

    We have developed a self-consistent theory of saturated tearing modes capable of predicting multiple magnetic island widths in tokamaks with no assumptions on the cross-sectional shape, aspect ratio, or plasma pressure. We are in the process of implementing this algorithm in the form of a computer code. We propose: (1) to complete, refine, document and publish this computer code; (2) to carry out a survey in which we vary the current profile, aspect ratio, cross-sectional shape, and pressure profile in order to determine their effect on saturated tearing mode magnetic island widths; and (3) to determine the effect of some externally applied magnetic perturbation harmonics on these magnetic island widths. Particular attention will be paid to the coupling between different helical harmonics, the effect of multiple magnetic islands on the profiles of temperature, pressure and current, and the potential of magnetic island overlap leading to a disruptive instability

  6. Stability of tearing modes in tokamak plasmas

    International Nuclear Information System (INIS)

    Hegna, C.C.; Callen, J.D.

    1994-02-01

    The stability properties of m ≥ 2 tearing instabilities in tokamak plasmas are analyzed. A boundary layer theory is used to find asymptotic solutions to the ideal external kink equation which are used to obtain a simple analytic expression for the tearing instability parameter Δ'. This calculation generalizes previous work on this topic by considering more general toroidal equilibria (however, toroidal coupling effects are ignored). Constructions of Δ' are obtained for plasmas with finite beta and for islands that have nonzero width. A simple heuristic estimate is given for the value of the saturated island width when the instability criterion is violated. A connection is made between the calculation of the asymptotic matching parameter in the finite beta and island width case to the nonlinear analog of the Glasser effect

  7. Geometrical influences on neoclassical magnetohydrodynamic tearing modes

    International Nuclear Information System (INIS)

    Kruger, S.E.; Hegna, C.C.; Callen, J.D.

    1997-07-01

    The influence of geometry on the pressure drives of nonideal magnetohydrodynamic tearing modes is presented. In order to study the effects of elongation, triangularity, and aspect ratio, three different machines are considered to provide a range of tokamak configurations: TFTR (circular), DIII-D (D-shaped), and Pegasus (extremely low aspect ratio). For large aspect ratio tokamaks, shaping does very little to influence the pressure gradient drives, while at low aspect ratios, a very strong sensitivity to the profiles is found. In particular, this sensitivity is connected to the strong dependence on the magnetic shear. This suggests that at low aspect ratio it may be possible to stabilize neoclassical tearing modes by flattening the q profile near low order rational surfaces (e.g., q = 2/1) using a combination of shaping and localized current drive, whereas at large aspect ratio it is more difficult

  8. 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.

  9. Artificial tears potpourri: a literature review

    OpenAIRE

    Moshirfar, Majid; Pierson, Kasey; Hanamaikai, Kamalani; Santiago-Caban, Luis; Muthappan, Valliammai; Passi, Samuel F

    2014-01-01

    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...

  10. Nonlinear growth of strongly unstable tearing modes

    International Nuclear Information System (INIS)

    Waelbroeck, F.L.

    1993-11-01

    Rutherford's theory of the tearing instability is extended to cases where current nonlinearities are important, such as long wavelength modes in current slabs and the m = 1 instability in tokamaks with moderately large aspect-ratios. Of particular interest is the possibility that the associated magnetic islands, as a result of secondary instabilities, have a singular response to the Ohmic diffusion of the current. A family of islands is used to test this possibility; it is found that the response remains bounded

  11. Magnetic resonance imaging of muscle tears

    International Nuclear Information System (INIS)

    De Smet, A.A.; Fisher, D.R.; Heiner, J.P.; Keene, J.S.

    1990-01-01

    Magnetic resonance scans were obtained on 17 patients with acute, subacute, or chronic muscle tears. These patients presented with complaints of persistent pain or a palpable mass. Magnetic resonance findings were characterized according to alterations in muscle shape and the presence of abnormal high signal within the injured muscle. These areas of high signal were noted on both T1-weighted and T2-weighted scans and were presumed to represent areas of intramuscular hemorrhage. (orig.)

  12. Small-scale tearing mode in tokamaks

    International Nuclear Information System (INIS)

    Ivanov, N.V.

    1983-01-01

    Considerations are given on the possible effect of small-scale tearing mode with m >> 1 on the plasma electron thermal conductivity in a tokamak. The estimate of the electron thermal conductivity coefficient is obtained. Calculation results are compared with experimental data. The calculated dependence of radial distribution of electron temperature is shown to vary weakly with the tn(m 2 /m 1 ) alteration everywhere, except for the vicinity of point r approximately 0

  13. Self-folding mechanics of graphene tearing and peeling from a substrate

    Science.gov (United States)

    He, Ze-Zhou; Zhu, Yin-Bo; Wu, Heng-An

    2018-06-01

    Understanding the underlying mechanism in the tearing and peeling processes of graphene is crucial for the further hierarchical design of origami-like folding and kirigami-like cutting of graphene. However, the complex effects among bending moduli, adhesion, interlayer interaction, and local crystal structure during origami-like folding and kirigami-like cutting remain unclear, resulting in challenges to the practical applications of existing theoretical and experimental findings as well as to potential manipulations of graphene in metamaterials and nanodevices. Toward this end, classical molecular dynamics (MD) simulations are performed with synergetic theoretical analysis to explore the tearing and peeling of self-folded graphene from a substrate driven by external force and by thermal activation. It is found that the elastic energy localized at the small folding ridge plays a significant role in the crack trajectory. Due to the extremely small bending modulus of monolayer graphene, its taper angle when pulled by an external force follows a scaling law distinct from that in case of bilayer graphene. With the increase in the initial width of the folding ridge, the self-folded graphene, motivated by thermal fluctuations, can be self-assembled by spontaneous self-tearing and peeling from a substrate. Simultaneously, the scaling law between the taper angle and adhesive energy is independent of the motivations for thermal activation-induced self-assembly and external force tearing, providing effective insights into the underlying physics for graphene-based origami-like folding and kirigami-like cutting.

  14. A two-fluid study of oblique tearing modes in a force-free current sheet

    Energy Technology Data Exchange (ETDEWEB)

    Akçay, Cihan, E-mail: akcay@lanl.gov; Daughton, William [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Lukin, Vyacheslav S. [National Science Foundation, Arlington, Virginia 22230 (United States); Liu, Yi-Hsin [NASA Goddard Space Flight Center, Greenbelt, Maryland 20771 (United States)

    2016-01-15

    Kinetic simulations have demonstrated that three-dimensional reconnection in collisionless regimes proceeds through the formation and interaction of magnetic flux ropes, which are generated due to the growth of tearing instabilities at multiple resonance surfaces. Since kinetic simulations are intrinsically expensive, it is desirable to explore the feasibility of reduced two-fluid models to capture this complex evolution, particularly, in the strong guide field regime, where two-fluid models are better justified. With this goal in mind, this paper compares the evolution of the collisionless tearing instability in a force-free current sheet with a two-fluid model and fully kinetic simulations. Our results indicate that the most unstable modes are oblique for guide fields larger than the reconnecting field, in agreement with the kinetic results. The standard two-fluid tearing theory is extended to address the tearing instability at oblique angles. The resulting theory yields a flat oblique spectrum and underestimates the growth of oblique modes in a similar manner to kinetic theory relative to kinetic simulations.

  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. Tearing modes with pressure gradient effect in pair plasmas

    International Nuclear Information System (INIS)

    Cai Huishan; Li Ding; Zheng Jian

    2009-01-01

    The general dispersion relation of tearing mode with pressure gradient effect in pair plasmas is derived analytically. If the pressure gradients of positron and electron are not identical in pair plasmas, the pressure gradient has significant influence at tearing mode in both collisionless and collisional regimes. In collisionless regime, the effects of pressure gradient depend on its magnitude. For small pressure gradient, the growth rate of tearing mode is enhanced by pressure gradient. For large pressure gradient, the growth rate is reduced by pressure gradient. The tearing mode can even be stabilized if pressure gradient is large enough. In collisional regime, the growth rate of tearing mode is reduced by the pressure gradient. While the positron and electron have equal pressure gradient, tearing mode is not affected by pressure gradient in pair plasmas.

  17. 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.

  18. 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

  19. Magnetic resonance imaging in acute and chronic rotator cuff tears

    International Nuclear Information System (INIS)

    Buirski, G.

    1990-01-01

    Magnetic resonance imaging has been assessed in patients with acute rotator cuff tears and normal radiographs (9 cases) and those with chronic tears and changes of cuff arthropathy (9 cases). All images were obtained using a low field strength system (FONAR 0.3 T). Particular attention was placed on the appearances of the tendon and the cuff muscles themselves. Six complete acute tears were clearly identified, but MRI failed to demonstrate two partial tears. Muscle bulk was preserved in all patients in this group. In contrast, all patients with cuff arthropathy had complete tears of the supraspinatus tendon with marked tendon retraction and associated muscle atrophy: These changes precluded primary surgical repair. MRI should be used to assess muscle atrophy preoperatively in those patients with acute tears. When plain radiographs demonstrate cuff arthropathy, the MRI appearances are predictable and primary repair is unlikely to be successful. Further imaging is therefore not indicated. (orig.)

  20. 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

  1. The 'bridging sign', a MR finding for combined full-thickness tears of the subscapularis tendon and the supraspinatus tendon

    International Nuclear Information System (INIS)

    Jung, Jin Young; Yoon, Young Cheol; Cha, Dong Ik; Yoo, Jae-Chul; Jung, Jee Young

    2013-01-01

    Background: In daily practice, we discovered one of the secondary magnetic resonance (MR) findings of the subscapularis (SSC) tendon tear, the 'bridging sign', which has not been previously described. Purpose: To describe the 'bridging sign' on shoulder MR imaging and its radiological and clinical significance in patients with SSC tendon tear. Material and Methods: Twenty-nine patients who had undergone shoulder arthroscopy and had full-thickness tear of the subscapularis tendon were enrolled. The medical records of the 29 patients were retrospectively reviewed for the duration of shoulder pain, rotator cuff tears, and associated arthroscopic findings: biceps tendon abnormality and superior glenoid labral tear. Then, preoperative shoulder MR images were retrospectively reviewed for the presence or absence of the 'bridging sign' and associated MR findings: periarticular fluid and fatty atrophy of the supraspinatus and subscapularis muscles. The type of rotator cuff tear associated with the 'bridging sign' was assessed and the sensitivity, specificity, and accuracy of the 'bridging sign' for the diagnosis of a certain type of rotator cuff tear were calculated. Associated arthroscopic and MR findings and mean duration of the shoulder pain between the patients with and without the 'bridging sign' were compared. Results: The 'bridging sign' was seen in 17 of 29 patients and corresponded to a complex of the torn and superomedially retracted subscapularis tendon, coracohumeral ligament, and superior glenohumeral ligament, adhered to the anterior margin of the torn supraspinatus (SSP) tendon on arthroscopy. All patients with the 'bridging sign' had combined full-thickness tear (FTT) of the cranial 1/2 portion of the subscapularis tendon and anterior 1/2 portion of the SSP tendon. The sensitivity, specificity, and accuracy of the 'bridging sign' for the diagnosis of combined FTTs of the SSC tendon and anterior portion of the SSP tendon were 81.0%, 100%, and 86

  2. 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

  3. Effect of blinking on tear elimination as evaluated by dacryoscintigraphy

    International Nuclear Information System (INIS)

    White, W.L.; Glover, A.T.; Buckner, A.B.

    1991-01-01

    To document the change in drainage of tears that occurs with blinking, the authors evaluated 17 lacrimal systems of 12 individuals with dacryoscintigraphy. A significant difference in tear drainage was found by keeping the eyelids closed during the first 2 minutes after drop placement (P less than 0.03), but not from 2 to 5 minutes (P greater than 0.4). Retardation of tear drainage after droplet placement can be achieved by simple eyelid closure for 2 minutes

  4. Statistics without Tears: Complex Statistics with Simple Arithmetic

    Science.gov (United States)

    Smith, Brian

    2011-01-01

    One of the often overlooked aspects of modern statistics is the analysis of time series data. Modern introductory statistics courses tend to rush to probabilistic applications involving risk and confidence. Rarely does the first level course linger on such useful and fascinating topics as time series decomposition, with its practical applications…

  5. Combined use of chondroitinase-ABC, TGF-β1, and collagen crosslinking agent lysyl oxidase to engineer functional neotissues for fibrocartilage repair.

    Science.gov (United States)

    Makris, Eleftherios A; MacBarb, Regina F; Paschos, Nikolaos K; Hu, Jerry C; Athanasiou, Kyriacos A

    2014-08-01

    Patients suffering from damaged or diseased fibrocartilages currently have no effective long-term treatment options. Despite their potential, engineered tissues suffer from inferior biomechanical integrity and an inability to integrate in vivo. The present study identifies a treatment regimen (including the biophysical agent chondroitinase-ABC, the biochemical agent TGF-β1, and the collagen crosslinking agent lysyl oxidase) to prime highly cellularized, scaffold-free neofibrocartilage implants, effecting continued improvement in vivo. We show these agents drive in vitro neofibrocartilage matrix maturation toward synergistically enhanced Young's modulus and ultimate tensile strength values, which were increased 245% and 186%, respectively, over controls. Furthermore, an in vitro fibrocartilage defect model found this treatment regimen to significantly increase the integration tensile properties between treated neofibrocartilage and native tissue. Through translating this technology to an in vivo fibrocartilage defect model, our results indicate, for the first time, that a pre-treatment can prime neofibrocartilage for significantly enhanced integration potential in vivo, with interfacial tensile stiffness and strength increasing by 730% and 745%, respectively, compared to integration values achieved in vitro. Our results suggest that specifically targeting collagen assembly and organization is a powerful means to augment overall neotissue mechanics and integration potential toward improved clinical feasibility. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. 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.

  7. Lipid peroxidation is increased in tears from the elderly.

    Science.gov (United States)

    Benlloch-Navarro, Soledad; Franco, Ilenia; Sánchez-Vallejo, Violeta; Silvestre, Dolores; Romero, Francisco Javier; Miranda, María

    2013-10-01

    We describe a procedure in which tears, obtained from Schirmer strips, are used to measure a marker of lipid peroxidation, malondialdehyde (MDA). We also compared the levels of proteins and MDA in tears from two groups of people: young adults (18-30 years old) and elderly adults (65-85 years old), because the data related to total protein concentration of human tears vary widely and because the majority of people over the age of 65 experience some symptoms of dry eyes and this condition has been recognized as an oxidative stress-induced disease. Our results show a significant difference in the protein concentration of the tears taken from the two age categories, younger adults (18-30 years old) and older adults (65-85 years old). Herein, we report for the first time an increase in MDA concentrations determined by HPLC in human tears based on age. It is possible that alterations in the tear lipid layer may lead to an increase in lipid peroxidation. Further studies are needed to understand the nature and function of tear film and stability in order to obtain new methods to analyze tears in patients with different diseases. In this sense, it would be interesting to compare MDA concentration in tears from control subjects and from people with meibomian gland dysfunction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Effects of tear film dynamics on quality of vision.

    Science.gov (United States)

    Koh, Shizuka; Tung, Cynthia I; Inoue, Yasushi; Jhanji, Vishal

    2018-06-15

    The precorneal tear film is maintained by blinking and exhibits different phases in the tear cycle. The tear film serves as the most anterior surface of the eye and plays an important role as a first refractive component of the eye. Alterations in tear film dynamics may cause both vision-related and ocular surface-related symptoms. Although the optical quality associated with the tear film dynamics previously received little attention, objective measurements of optical quality using wavefront sensors have enabled us to quantify optical aberrations induced by the tear film. This has provided an objective method for assessing reduced optical quality in dry eye; thus, visual disturbances were included in the definition of dry eye disease in the 2007 Dry Eye Workshop report. In addition, sequential measurements of wavefront aberrations have provided us with valuable insights into the dynamic optical changes associated with tear film dynamics. This review will focus on the current knowledge of the mechanisms of wavefront variations that are caused by different aspects of tear film dynamics: specifically, quality, quantity and properties of the tear film, demonstrating the respective effects of dry eye, epiphora and instillation of eye drops on the quality of vision. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  9. Accuracy of MR imaging in partial tears of rotator cuff

    International Nuclear Information System (INIS)

    Eto, Masao; Ito, Nobuyuki; Tomonaga, Tadashi; Harada, Shin'ichi; Rabbi, M.E.; Iwasaki, Katsuro

    1997-01-01

    MRI is very useful for the diagnosis of the rotator cuff tear However. in case of partial tears it is sometimes controvertible. In this study, we studied the accuracy of MRI in the diagnosis of partial tears. 67 patients who underwent MRI investigation before operation were chosen for this study. There were 61 males and 6 females, ranging from 30 to 80 years (mean: 54.8 years at the time of operation). MRI was performed with 1.5T superconductive system with shoulder surface coil. MPGR T2-weighted images were performed in the coronal oblique and sagittal oblique planes. Complete tears were diagnosed when full thickness high intensity was observed in the rotator cuff, whereas with partial high intensity of the rotator cuff, was considered as partial tears. MRI demonstrated 77.8% sensitivity, 91.4% specificity and 89.6% accuracy in the diagnosis of partial tear. In 8 cases MRI had misinterpretation. In MPGR T2-weighted images, not only the partial tears but the degenerative changes also show high intensity of the rotator cuff. Therefore, it is difficult to differentiate and maybe this is the reason of misinterpretations of partial tears by MRI. MRI provided with useful pre-operative informations of partial tears of the rotator cuff. However, in few cases it is hard to differentiate for the degenerative changes of the rotator cuff. (author)

  10. Assessment and treatment strategies for rotator cuff tears

    Science.gov (United States)

    Al-Hakim, Wisam; Noorani, Ali

    2014-01-01

    Tears of the rotator cuff are common and becoming an increasingly frequent problem. There is a vast amount of literature on the merits and limitations of the various methods of clinical and radiological assessment of rotator cuff tears. This is also the case with regard to treatment strategies. Certain popular beliefs and principles practiced widely and the basis upon which they are derived may be prone to inaccuracy. We provide an overview of the historical management of rotator cuff tears, as well as an explanation for how and why rotator cuff tears should be managed, and propose a structured methodology for their assessment and treatment. PMID:27582960

  11. Progression of Fatty Muscle Degeneration in Atraumatic Rotator Cuff Tears.

    Science.gov (United States)

    Hebert-Davies, Jonah; Teefey, Sharlene A; Steger-May, Karen; Chamberlain, Aaron M; Middleton, William; Robinson, Kathryn; Yamaguchi, Ken; Keener, Jay D

    2017-05-17

    The purpose of this prospective study was to examine the progression of fatty muscle degeneration over time in asymptomatic shoulders with degenerative rotator cuff tears. Subjects with an asymptomatic rotator cuff tear in 1 shoulder and pain due to rotator cuff disease in the contralateral shoulder were enrolled in a prospective cohort. Subjects were followed annually with shoulder ultrasonography, which evaluated tear size, location, and fatty muscle degeneration. Tears that were either full-thickness at enrollment or progressed to a full-thickness defect during follow-up were examined. A minimum follow-up of 2 years was necessary for eligibility. One hundred and fifty-six shoulders with full-thickness rotator cuff tears were potentially eligible. Seventy shoulders had measurable fatty muscle degeneration of at least 1 rotator cuff muscle at some time point. Patients with fatty muscle degeneration in the shoulder were older than those without degeneration (mean, 65.8 years [95% confidence interval (CI), 64.0 to 67.6 years] compared with 61.0 years [95% CI, 59.1 to 62.9 years]; p tears at baseline was larger in shoulders with degeneration than in shoulders that did not develop degeneration (13 and 10 mm wide, respectively, and 13 and 10 mm long; p Tears with fatty muscle degeneration were more likely to have enlarged during follow-up than were tears that never developed muscle degeneration (79% compared with 58%; odds ratio, 2.64 [95% CI, 1.29 to 5.39]; p muscle degeneration occurred more frequently in shoulders with tears that had enlarged (43%; 45 of 105) than in shoulders with tears that had not enlarged (20%; 10 of 51; p tears with enlargement and progression of muscle degeneration were more likely to extend into the anterior supraspinatus than were those without progression (53% and 17%, respectively; p tear size (p = 0.56). The median time from tear enlargement to progression of fatty muscle degeneration was 1.0 year (range, -2.0 to 6.9 years) for the

  12. 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.

  13. 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

  14. 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

  15. 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.

  16. Third- or Fourth-Degree Intrapartum Anal Sphincter Tears Are Associated With Levator Ani Avulsion in Primiparas.

    Science.gov (United States)

    Valsky, Dan V; Cohen, Sarah M; Lipschuetz, Michal; Hochner-Celnikier, Drorith; Daum, Hagit; Yagel, Itai; Yagel, Simcha

    2016-04-01

    We evaluated primiparous women with clinically diagnosed third- and fourth-degree and anal sphincter tears, to evaluate the rate of levator ani muscle injury compared to primiparous women without sphincter tears. Primiparous women delivering in our maternity ward with intrapartum diagnoses of third- or fourth-degree anal sphincter tears, repaired by the overlapping technique, were recruited to undergo 3-dimensional transperineal sonography of the pelvic floor anatomy, including the anterior and posterior compartments. Primiparas with uncomplicated vaginal deliveries were recruited as a comparison group. Patient files were examined, and maternal backgrounds and delivery and neonatal details were extracted for all patients. Ninety-four women with tears were recruited to the study group, and 464 women with normal vaginal deliveries constituted the comparison group. The groups differed significantly in the rates of levator ani defects: 38 of 94 women (40.4%) in the study group versus 75 of 464 (16.2%) in the comparison group (P tears are associated with levator ani avulsion. Knowledge of complex pelvic floor damage may allow for prompt referral to secondary preventive measures for pelvic floor disorders. © 2016 by the American Institute of Ultrasound in Medicine.

  17. Treatment for acute anterior cruciate ligament tear

    DEFF Research Database (Denmark)

    Frobell, Richard B; Roos, Harald P; Roos, Ewa M

    2015-01-01

    STUDY QUESTION: In young active adults with an acute anterior cruciate ligament (ACL) rupture, do patient reported or radiographic outcomes after five years differ between those treated with rehabilitation plus early ACL reconstruction and those treated with rehabilitation and optional delayed AC...... AND WHAT THIS PAPER ADDS: The relative efficacy of surgical reconstruction and rehabilitation for short and long term outcomes of ACL rupture is debated. Clinicians and young active adult patients should consider rehabilitation as a primary treatment option following an acute ACL tear....

  18. Tearing instability in cylindrical plasma configuration

    International Nuclear Information System (INIS)

    Zelenyj, L.M.

    1979-01-01

    The effect of the neutral-layer cylindrical geometry on the development of the tearing instability has been investigated in detail. The increments of the instability for all the regimes have been found. The influence of cylindrical effects becomes manifesting itself at small, as compared to the layer characteristic thickness, distances from the axis, and, finally, the electron regime of the instability development transforms into an ion one. The results obtained are of interest for studying the plasma stability in the devices of the ''Astron'' type and in magnetospheres of cosmic objects

  19. The Usefulness of Dynamic Cine-Arthrography for Wrist Instability as Correlated with Arthroscopic Palmer Classification

    Energy Technology Data Exchange (ETDEWEB)

    Kim TaeYeon; Lee, Guen Young; Kim, Baek Hyun; Park, Jong Woong; Seo, Bo Kyoung; Cha, Sang Hoon [Korea University Ansan Hospital, Korea University College of Medicine, Ansan (Korea, Republic of)

    2011-05-15

    To introduce dynamic cine-arthrography and compare it with MR arthrography in the diagnosis of intrinsic ligament and triangular fibrocartilage complex tears, based on arthroscopic findings. A total of thirty-eight wrists of 38 patients who had undergone both dynamic cine-arthrography and MR arthrography were enrolled. Dynamic cinearthrography was performed after puncture of the radiocarpal joint by slow injection of contrast under continuous fluoroscopic guidance during passive wrist exercise. We obtained 1.5- or 3-T MR arthrography with fat-suppressed T1-weighted coronal and axial images. We evaluated scapholunate and lunotriquetral ligaments and triangular fibrocartilage complex tears according to the Palmer classification system. Based on the arthroscopic findings, we compared the diagnostic values between the two examinations using Kappa values. The overall sensitivity and specificity of diagnosis of intrinsic ligament tears was similar between dynamic cine-arthrography and MR arthrography (scapholunate ligament: sensitivity 66.7% vs. 80%, specificity 100% vs. 95.7%, lunotriquetral ligament: sensitivity 75.0% vs. 75.0%, specificity 94.1% vs. 91.2%). For triangular fibrocartilage complex tears, all diagnostic values were the same (sensitivity 96.4%, specificity 100%). The inter-examination agreement was substantial to perfect (kappa value 1.000). Dynamic cine-arthrography is valuable in the diagnosis of intrinsic ligament and triangular fibrocartilage complex tears compared to MR arthrography.

  20. [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

  1. 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.

  2. 49 CFR 173.340 - Tear gas devices.

    Science.gov (United States)

    2010-10-01

    ... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.340 Tear gas devices. (a) Packagings for...) Tear gas devices may not be assembled with, or packed in the same packaging with, mechanically- or manually-operated firing, igniting, bursting, or other functioning elements unless of a type and design...

  3. Tear film lipid layer: A molecular level view

    Czech Academy of Sciences Publication Activity Database

    Cwiklik, Lukasz

    2016-01-01

    Roč. 1858, č. 10 (2016), s. 2421-2430 ISSN 0005-2736 R&D Projects: GA ČR GA15-14292S Institutional support: RVO:61388955 Keywords : tear film * tear film lipid layer * molecular dynamics simulations Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.498, year: 2016

  4. Why only humans shed emotional tears : Evolutionary and cultural perspectives

    NARCIS (Netherlands)

    Gracanin, A.; Bylsma, L.M.; Vingerhoets, A.J.J.M.

    Producing emotional tears is a universal and uniquely human behavior. Until recently, tears have received little serious attention from scientists. Here, we summarize recent theoretical developments and research findings. The evolutionary approach offers a solid ground for the analysis of the

  5. Tearing mode stability of tokamak plasmas with elliptical cross section

    International Nuclear Information System (INIS)

    Carreras, B.A.; Holmes, J.A.; Hicks, H.R.; Lynch, V.E.

    1981-02-01

    The effect of the ellipticity of the plasma cross section on tearing mode stability is investigated. The induced coupling between modes is shown to be destabilizing; however, the modification of the equilibrium tends to stabilize the tearing modes. The net effect depends on the manner in which the equilibrium is modified as the plasma cross-section shape is changed

  6. The Effect of Polar Lipids on Tear Film Dynamics

    KAUST Repository

    Aydemir, E.; Breward, C. J. W.; Witelski, T. P.

    2010-01-01

    In this paper, we present a mathematical model describing the effect of polar lipids, excreted by glands in the eyelid and present on the surface of the tear film, on the evolution of a pre-corneal tear film. We aim to explain the interesting

  7. 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)

  8. 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)

  9. Nonlinear tearing mode and vortex chains

    International Nuclear Information System (INIS)

    Jovanovic, D.; Vranjes, J.

    1996-01-01

    We study the nonlinear stage of a tearing mode, whose island width exceeds the tearing layer thickness, and the wavelength is of the order of collisionless skin depth. A coherent solution is found in the form of a moving vortex chain. It is the result of a self-organization process, which adjusts the profile of the sheared poloidal magnetic field and excites a localized perpendicular sheared plasma flow, consisting of three counterstreaming jets. A numerical solution shows a twin chain of plasma vortices, coupled with a single chain of magnetic islands, whose width is of the order of collisionless skin depth. Adiabatic evolution of the vortex chain in the presence of small viscosity reveals its finite lifetime. The chain destruction may occur either directly, or through a sequence of bifurcations (corresponding to abrupt changes of the vortex chain parameters) to magnetic field stochastization within a layer of the collisionless skin depth scale, which occurs before the magnetic island overlapping takes place. This provides a new mechanism for the anomalous transport. (orig.)

  10. Tearing modes induced by perpendicular electron cyclotron resonance heating in the KSTAR tokamak

    International Nuclear Information System (INIS)

    Lee, H.H.; Lee, S.G.; Seol, J.; Aydemir, A.Y.; Bae, C.; Woo, M.H.; Kim, J.; Joung, M.; You, K.I.; Park, B.H.; Yoo, J.W.; Na, Y.S.; Kim, H.S.

    2014-01-01

    This paper reports on experimental evidence that shows perpendicular electron cyclotron resonance heating (ECRH) can trigger classical tearing modes when deposited near a rational flux surface. The complex evolution of an m = 2 island is followed during current ramp-up in KSTAR plasmas, from its initial onset as the rational surface enters the ECRH resonance layer to its eventual lock on the wall after the rational surface leaves the layer. Stability analysis coupled to a transport calculation of the current profile with ECRH shows that the perpendicular ECRH may play a significant role in triggering and destabilizing classical m = 2 tearing modes, in agreement with our experimental observation. (paper)

  11. 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.

  12. 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.

  13. Dynamic tensile loading improves the functional properties of mesenchymal stem cell-laden nanofiber-based fibrocartilage.

    Science.gov (United States)

    Baker, Brendon M; Shah, Roshan P; Huang, Alice H; Mauck, Robert L

    2011-05-01

    Fibrocartilaginous tissues such as the meniscus serve critical load-bearing roles, relying on arrays of collagen fibers to resist tensile loads experienced with normal activity. As these structures are frequently injured and possess limited healing capacity, there exists great demand for tissue-engineered replacements. Toward recreating the structural features of these anisotropic tissues in vitro, we employ scaffolds composed of co-aligned nanofibers that direct mesenchymal stem cell (MSC) orientation and the formation of organized extracellular matrix (ECM). Concomitant with ECM synthesis, the mechanical properties of constructs increase with free-swelling culture, but ultimately failed to achieve equivalence with meniscal fibrocartilage. As mechanical forces are essential to the development and maintenance of musculoskeletal tissues, this work examined the effect of cyclic tensile loading on MSC-laden nanofibrous constructs. We hypothesized that loading would modulate the transcriptional behavior of MSCs, spur the deposition of ECM, and lead to enhancements in construct mechanical properties compared to free-swelling controls. Fiber-aligned scaffolds were seeded with MSCs and dynamically loaded daily in tension or maintained as nonloaded controls for 4 weeks. With mechanical stimulation, fibrous gene expression increased, collagen deposition increased, and the tensile modulus increased by 16% relative to controls. These results show that dynamic tensile loading enhances the maturation of MSC-laden aligned nanofibrous constructs, suggesting that recapitulation of the structural and mechanical environment of load-bearing tissues results in increases in functional properties that can be exploited for tissue engineering applications.

  14. T2[sup *] weighted MR imaging for the diagnosis of the perforation of triangular fibrocartilage; Comparison with arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Taro; Nakamura, Eiziro; Ahsoh, Kuniichi; Masumi, Shogo (Oita Medical Univ., Takatsuki (Japan))

    1994-05-01

    Perforation of the triangular fibrocartilage (TFC) has been considered an important factor in the etiology of pain in the ulnar wrist joint, and arthrography has been used conventionally to diagnose the perforation. Recently, magnetic resonance imaging (MRI) has been used to diagnose TFC perforation. Gundy et al. examined cadaver wrists with Tl weighted imaging and arthrography, and obtained findings suggesting that arthrography provides a more accurate diagnosis of the TFC perforation. To our knowledge, no comparison has yet been made between T2[sup *] weighted imaging and arthrography in the diagnosis of TFC perforation. The present study compared the usefulness of T2[sup *]-weighted imaging and arthrography in the diagnosis of TFC perforation in 22 wrist joints of 11 cadavers (5 males and 6 females with ages ranging from 61 to 92 years and an average age of 78.8 years) fixed in 60% formalin. The specimens were firstly analyzed by a T2[sup *]-weighted 0.5T MRI scan and subsequently by arthrography. After diagnosing the image obtained by the two methods, the accuracy of the diagnosis was determined by comparison with the macroscopic findings of autopsy, including the presence and degree of TFC perforation. A T2[sup *]-weighted MRI scan of the TFC perforation showed high-intensity areas over the distal radio-ulnar joint, and demonstrated the same diagnostic accuracy as arthrography, providing correct diagnoses in all cases other than linear perforation. However, neither of the image diagnostic methods allowed definition of the type of perforation. (author).

  15. 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.

  16. Effect of low-dose irradiation on structural and mechanical properties of hyaline cartilage-like fibrocartilage.

    Science.gov (United States)

    Öncan, Tevfik; Demirağ, Burak; Ermutlu, Cenk; Yalçinkaya, Ulviye; Özkan, Lütfü

    2013-01-01

    The aim of this study was to analyze the effect of low-dose irradiation on fibrous cartilage and to obtain a hyaline cartilage-like fibrocartilage (HCLF) with similar structural and mechanical properties to hyaline cartilage. An osteochondral defect was created in 40 knees of 20 rabbits. At the 7th postoperative day, a single knee of each rabbit was irradiated with a total dose of 5.0 Gy in 1.0 Gy fractions for 5 days (radiotherapy group), while the other knee was not irradiated (control group). Rabbits were then divided into four groups of 5 rabbits each. The first three groups were sacrificed at the 4th, 8th and the 12th postoperative weeks and cartilage defects were macroscopically and microscopically evaluated. The remaining group of 5 rabbits was sacrificed at the 12th week and biomechanical compression tests were performed on the cartilage defects. There was no significant biomechanical difference between the radiotherapy and the control group (p=0.686). There was no significant macroscopic and microscopic difference between groups (p=0.300). Chondrocyte clustering was observed in the irradiated group. Low-dose irradiation does not affect the mechanical properties of HCLF in vivo. However, structural changes such as chondrocyte clustering were observed.

  17. Delayed gadolinium-enhanced MRI of the fibrocartilage disc of the temporomandibular joint – a feasibility study

    Science.gov (United States)

    Pittschieler, Elisabeth; Szomolanyi, Pavol; Schmid-Schwap, Martina; Weber, Michael; Egerbacher, Monika; Traxler, Hannes; Trattnig, Siegfried

    2014-01-01

    Objective To 1) test the feasibility of delayed Gadolinium-Enhanced Magnetic Resonance Imaging of Cartilage (dGEMRIC) at 3 T in the temporomandibular joint (TMJ) and 2) to determine the optimal delay for measurements of the TMJ disc after i.v. contrast agent (CA) administration. Design MRI of the right and left TMJ of six asymptomatic volunteers was performed at 3 T using a dedicated coil. 2D inversion recovery (2D-IR) sequences were performed at 4 time points covering 120 minutes and 3D gradient-echo (3D GRE) dual flip-angle sequences were performed at 14 time points covering 130 minutes after the administration of 0.2 mmol/kg of Gd-diethylenetriamine pentaacetic acid ion (Gd-DTPA)2-, i.e., 0.4 mL of Magnevist™ per kg body weight. Pair-wise tests were used to assess differences between pre-and post-contrast T1 values. Results 2D-IR sequences showed a statistically significant drop (p fibrocartilage disc of the TMJ. The recommended measurement time for dGEMRIC in the TMJ after i.v. CA administration is from 60 to 120 minutes. PMID:25131629

  18. Which cartilage is regenerated, hyaline cartilage or fibrocartilage? Non-invasive ultrasonic evaluation of tissue-engineered cartilage.

    Science.gov (United States)

    Hattori, K; Takakura, Y; Ohgushi, H; Habata, T; Uematsu, K; Takenaka, M; Ikeuchi, K

    2004-09-01

    To investigate ultrasonic evaluation methods for detecting whether the repair tissue is hyaline cartilage or fibrocartilage in new cartilage regeneration therapy. We examined four experimental rabbit models: a spontaneous repair model (group S), a large cartilage defect model (group L), a periosteal graft model (group P) and a tissue-engineered cartilage regeneration model (group T). From the resulting ultrasonic evaluation, we used %MM (the maximum magnitude of the measurement area divided by that of the intact cartilage) as a quantitative index of cartilage regeneration. The results of the ultrasonic evaluation were compared with the histological findings and histological score. The %MM values were 61.1 +/- 16.5% in group S, 29.8 +/- 15.1% in group L, 36.3 +/- 18.3% in group P and 76.5 +/- 18.7% in group T. The results showed a strong similarity to the histological scoring. The ultrasonic examination showed that all the hyaline-like cartilage in groups S and T had a high %MM (more than 60%). Therefore, we could define the borderline between the two types of regenerated cartilage by the %MM.

  19. 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.

  20. 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

  1. Cytokine changes in tears and relationship to contact lens discomfort.

    Science.gov (United States)

    Willcox, Mark D P; Zhao, Zhenjun; Naduvilath, Thomas; Lazon de la Jara, Percy

    2015-01-01

    To determine the reproducibility of a multiplex bead assay for measuring cytokines in tears and correlations between ocular discomfort with or without contact lens wear and the concentration of cytokines in tears. Ninety participants (divided into two groups) were enrolled in this prospective study. They were asked to rate their ocular comfort and collect their tears in the morning and just before sleep for 10 days with or without contact lenses. The participants collected their tears using a glass microcapillary tube for both stages. Galyfilcon A lenses were worn on a daily disposable basis during the contact lens stage, and comfort scores and tears were collected before lens insertion and prior to lens removal at the end of the day. Tears were analyzed for cytokine concentrations using a 27-plex multibead assay. Correlations were sought between cytokine concentrations and comfort. There was a significant (p-0.5 Log pg/ml, p-0.2 Log pg/ml, ptears was correlated to ocular comfort, but this was not changed by contact lens wear. Ocular comfort during the day is magnified by contact lens wear. However, the increase in the change in comfort during lens wear was not associated with changes in 15 cytokines in the tear film.

  2. Relationships between rotator cuff tear types and radiographic abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soo Hyun; Chun, Kyung Ah; Lee Soo Jung; Kang, Min Ho; Yi, Kyung Sik; Zhang, Ying [Dept. of Diagnostic Radiology, College of Medicine, Chungbuk National University, Cheongju (Korea, Republic of)

    2014-11-15

    To determine relationships between different types of rotator cuff tears and radiographic abnormalities. The shoulder radiographs of 104 patients with an arthroscopically proven rotator cuff tear were compared with similar radiographs of 54 age-matched controls with intact cuffs. Two radiologists independently interpreted all radiographs for; cortical thickening with subcortical sclerosis, subcortical cysts, osteophytes in the humeral greater tuberosity, humeral migration, degenerations of the acromioclavicular and glenohumeral joints, and subacromial spurs. Statistical analysis was performed to determine relationships between each type of rotator cuff tears and radiographic abnormalities. Inter-observer agreements with respect to radiographic findings were analyzed. Humeral migration and degenerative change of the greater tuberosity, including sclerosis, subcortical cysts, and osteophytes, were more associated with full-thickness tears (p < 0.01). Subacromial spurs were more common for full-thickness and bursal-sided tears (p < 0.01). No association was found between degeneration of the acromioclavicular or glenohumeral joint and the presence of a cuff tear. Different types of rotator cuff tears are associated with different radiographic abnormalities.

  3. Relationships between rotator cuff tear types and radiographic abnormalities

    International Nuclear Information System (INIS)

    Lee, Soo Hyun; Chun, Kyung Ah; Lee Soo Jung; Kang, Min Ho; Yi, Kyung Sik; Zhang, Ying

    2014-01-01

    To determine relationships between different types of rotator cuff tears and radiographic abnormalities. The shoulder radiographs of 104 patients with an arthroscopically proven rotator cuff tear were compared with similar radiographs of 54 age-matched controls with intact cuffs. Two radiologists independently interpreted all radiographs for; cortical thickening with subcortical sclerosis, subcortical cysts, osteophytes in the humeral greater tuberosity, humeral migration, degenerations of the acromioclavicular and glenohumeral joints, and subacromial spurs. Statistical analysis was performed to determine relationships between each type of rotator cuff tears and radiographic abnormalities. Inter-observer agreements with respect to radiographic findings were analyzed. Humeral migration and degenerative change of the greater tuberosity, including sclerosis, subcortical cysts, and osteophytes, were more associated with full-thickness tears (p < 0.01). Subacromial spurs were more common for full-thickness and bursal-sided tears (p < 0.01). No association was found between degeneration of the acromioclavicular or glenohumeral joint and the presence of a cuff tear. Different types of rotator cuff tears are associated with different radiographic abnormalities.

  4. Coupling of tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Finn, J.M.

    1977-01-01

    The simultaneous presence of tearing modes of different helical pitches leads to the destruction of magnetic surfaces, which has been suggested as the mechanism leading to the onset of the disruptive instability in tokamaks. For current profiles in which the m = 2 mode is unstable, but the m = 3 is stable, the coupling of the m = 3 to the m = 2 through the poloidal variation of the toroidal field can drive the m = 3 amplitude psi 3 to order psi 2 times the inverse aspect ratio. Detailed calculations, both analytical and numerical, have been performed for two models for the equilibrium and m = 2 mode structure. A slab model and incompressible m = 3 perturbations are assumed. The m = 3 amplitude increases with shear, up to a point, showing that as the current channel shrinks, overlap of resonances becomes more likely. The results also apply qualitatively to other m, m +- 1 interactions

  5. 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

  6. Tear Mediators in Corneal Ectatic Disorders.

    Directory of Open Access Journals (Sweden)

    Dorottya Pásztor

    Full Text Available To compare the concentrations of 11 tear mediators in order to reveal the biochemical difference between pellucid marginal degeneration (PMD and keratoconus (KC.We have designed a cross-sectional study in which patients with corneal ectasia based on slit-lamp biomicroscopy and Pentacam HR (keratometry values (K1, K2, Kmax, astigmatism, minimal radius of curvature (Rmin, corneal thickness (Apex and Min, indices (surface variation, vertical asymmetry, keratoconus, central keratoconus, height asymmetry and decentration were enrolled. Eyes of keratoconic patients were similar to the PMD patients in age and severity (K2, Kmax and Rmin. Non-stimulated tear samples were collected from nine eyes of seven PMD patients, 55 eyes of 55 KC patients and 24 eyes of 24 healthy controls. The mediators' (interleukin -6, -10, chemokine ligand 5, -8, -10, matrix metalloproteinase (MMP -9, -13, tissue inhibitor of metalloproteinases (TIMP-1, tissue plasminogen activator, plasminogen activator inhibitor, nerve growth factor concentrations were measured using Cytometric Bead Array.MMP-9 was the only mediator which presented relevant variances between the two patient groups (p = 0.005. The ratios of MMP-9 and TIMP-1 were 2.45, 0.40 and 0.23 in PMD, KC and the controls, respectively.As far as we are aware, this is the first study that aims to reveal the biochemical differences between PMD and KC. Further studies of biomarkers to investigate the precise role of these mediators need to be defined, and it is important to confirm the observed changes in a larger study to gain further insights into the molecular alterations in PMD.

  7. The relationship between tear severity, fatty infiltration, and muscle atrophy in the supraspinatus.

    Science.gov (United States)

    Barry, Jeffrey J; Lansdown, Drew A; Cheung, Sunny; Feeley, Brian T; Ma, C Benjamin

    2013-01-01

    Fatty infiltration and muscle atrophy have been described as interrelated characteristic changes that occur within the muscles of the rotator cuff after cuff tears, and both are independently associated with poor outcomes after surgical repair. We hypothesize that fatty infiltration and muscle atrophy are two distinct processes independently associated with supraspinatus tears. A retrospective review of 377 patients who underwent shoulder magnetic resonance imaging at one institution was performed. Multivariate analysis was performed based on parameters including age, sex, rotator cuff tear severity, fatty infiltration grade, and muscle atrophy. A total of 116 patients (30.8%) had full-thickness tears of the supraspinatus, 153 (40.6%) had partial thickness tears, and 108 (28.7%) had no evidence of tear. With increasing tear severity, the prevalence of substantial fatty infiltration (grade ≥2) increased: 6.5% of patients with no tears vs 41.4% for complete tears (P tear severity: 36.1% of no tears vs 77.6% of complete tears (P muscle atrophy when taking into account sex, age, and tear severity. Fatty infiltration and muscle atrophy are independently associated processes. Fatty infiltration is also related to increasing age, muscle tear severity, and sex, whereas muscle atrophy is related to increasing age but not tear severity. In patients without rotator cuff tears, fatty infiltration and atrophy prevalence increased independently with increasing age. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  8. [In vitro differentiation of synovial-derived mesenchymal stem cells infected by adenovirus vector mediated by bone morphogenetic protein 2/7 genes into fibrocartilage cells in rabbits].

    Science.gov (United States)

    Fu, Peiliang; Zhang, Lei; Wu, Haishan; Cong, Ruijun; Chen, Song; Ding, Zheru; Hu, Kaimen

    2013-03-01

    To investigate the feasibility of rabbit synovial-derived mesenchymal stem cells (SMSCs) differentiating into fibrocartilage cells by the recombinant adenovirus vector mediated by bone morphogenetic protein 2/7 (BMP-2/7) genes in vitro. SMSCs were isolated and purified from 3-month-old New Zealand white rabbits [male or female, weighing (2.1 +/- 0.3) kg]; the morphology was observed; the cells were identified with immunocytological fluorescent staining, flow cytometry, and cell cycles. The adipogenic, osteogenic, and chondrogenic differentiations were detected. The recombinant plasmid of pAdTrack-BMP-2-internal ribosome entry site (IRES)-BMP-7 was constructed and then was used to infect SMSCs. The cell DNA content and the oncogenicity were tested to determine the safety. Then infected SMSCs were cultured in incomplete chondrogenic medium in vitro. Chondrogenic differentiation of infected SMSCs was detected by RT-PCR, immunofluorescent staining, and toluidine blue staining. SMSCs expressed surface markers of stem cells, and had multi-directional potential. The transfection efficiency of SMSCs infected by recombinant plasmid of pAdTrack-BMP-2-IRES-BMP-7 was about 70%. The safety results showed that infected SMSCs had normal double time, normal chromosome number, and normal DNA content and had no oncogenicity. At 21 days after cultured in incomplete chondrocyte medium, RT-PCR results showed SMSCs had increased expressions of collegan type I and collegan type II, particularly collegan type II; the expressions of RhoA and Sox-9 increased obviously. Immunofluorescent staining and toluidine blue staining showed differentiation of SMSCs into fibrocartilage cells. It is safe to use pAdTrack-BMP-2-IRES-BMP-7 for infecting SMSCs. SMSCs infected by pAdTrack-BMP-2-IRES-BMP-7 can differentiate into fibrocartilage cells spontaneously in vitro.

  9. From current-driven to neoclassically driven tearing modes.

    Science.gov (United States)

    Reimerdes, H; Sauter, O; Goodman, T; Pochelon, A

    2002-03-11

    In the TCV tokamak, the m/n = 2/1 island is observed in low-density discharges with central electron-cyclotron current drive. The evolution of its width has two distinct growth phases, one of which can be linked to a "conventional" tearing mode driven unstable by the current profile and the other to a neoclassical tearing mode driven by a perturbation of the bootstrap current. The TCV results provide the first clear observation of such a destabilization mechanism and reconcile the theory of conventional and neoclassical tearing modes, which differ only in the dominant driving term.

  10. Experimental observations of the tearing of an electron current sheet

    International Nuclear Information System (INIS)

    Gekelman, W.; Pfister, H.

    1988-01-01

    A neutral magnetic sheet, in which the current is carried mainly by the electrons, is set up in a laboratory plasma. By forcing the current through a thin slot, the ratio of the length to height t of the sheet may be varied; the current is observed to tear when tapprox. >30. The structure of the magnetic islands and their associated currents is fully three dimensional, although a linear two-dimensional theory gives a very good estimate of the tearing mode growth time. Tearing is accompanied by the generation of significant Hall currents, and magnetic disturbances are observed to propagate at the whistler wave speed

  11. Non-linear evolution of double tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Fredrickson, E.; Bell, M.; Budny, R.V.; Synakowski, E.

    1999-01-01

    The delta prime formalism with neoclassical modifications has proven to be a useful tool in the study of tearing modes in high beta, collisionless plasmas. In this paper the formalism developed for the inclusion of neoclassical effects on tearing modes in monotonic q-profile plasmas is extended to plasmas with hollow current profiles and double rational surfaces. First, the classical formalism of tearing modes in the Rutherford regime in low beta plasmas is extended to q profiles with two rational surfaces. Then it is shown that this formalism is readily extended to include neoclassical effects

  12. Tearing modes in tokamaks with lower hybrid current drive

    International Nuclear Information System (INIS)

    Xu, X.Q.

    1990-08-01

    In this paper, the effect of current drive on the tearing modes in the semi-collisional regime is analyzed using the drift-kinetic equation. A collisional operator is developed to model electron parallel conductivity. For the pure tearing modes the linear and quasilinear growth rates in the Rutherford regimes have been found to have roughly the same forms with a modified resistivity as without current drive. One interesting result is the prediction of a new instability. This instability, driven by the current gradient inside the tearing mode layer, is possibly related to MHD behavior observed in these experiments. 9 refs

  13. Threshold condition for nonlinear tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Zabiego, M.F.; Callen, J.D.

    1996-03-01

    Low-mode-number tearing, mode nonlinear evolution is analyzed emphasizing the need for a threshold condition, to account for observations in tokamaks. The discussion is illustrated by two models recently introduced in the literature. The models can be compared with the available data and/or serve as a basis for planning some experiments in order to either test theory (by means of beta-limit scaling laws, as proposed in this paper) or attempt to control undesirable tearing modes. Introducing a threshold condition in the tearing mode stability analysis is found to reveal some bifurcation points and thus domains of intrinsic stability in the island dynamics operational space

  14. Diagnosis of subscapularis lesion in rotator cuff tears

    International Nuclear Information System (INIS)

    Terrier, F.; Wegmueller, H.; Vock, P.; Gerber, C.

    1989-01-01

    In rotator cuff tears, the subscapularis tendon is more often involved than previously suspected, and this lesion is often missed at arthrography. Because preoperative diagnosis is important for planning surgical repair, the authors have evaluated MR imaging and US in the detection of subscapularis tears. Fifteen patients with clinically suspected rotator cuff tears underwent MR imaging and US. Ten of 15 patients were treated surgically, and the other five were treated conservatively. MR imaging was performed with a 1.5-T Signa MR system. T1-weighted spin-echo (SE) and T2-weighted gradient-echo (GE) images were obtained

  15. 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.

  16. Sonographic Visualization of the Rotator Cable in Patients With Symptomatic Full-Thickness Rotator Cuff Tears: Correlation With Tear Size, Muscular Fatty Infiltration and Atrophy, and Functional Outcome.

    Science.gov (United States)

    Bureau, Nathalie J; Blain-Paré, Etienne; Tétreault, Patrice; Rouleau, Dominique M; Hagemeister, Nicola

    2016-09-01

    To assess the prevalence of sonographic visualization of the rotator cable in patients with symptomatic full-thickness rotator cuff tears and asymptomatic controls and to correlate rotator cable visualization with tear size, muscular fatty infiltration and atrophy, and the functional outcome in the patients with rotator cuff tears. Fifty-seven patients with rotator cuff tears and 30 asymptomatic volunteers underwent shoulder sonography for prospective assessment of the rotator cable and rotator cuff tear and responded to 2 functional outcome questionnaires (shortened Disabilities of the Arm, Shoulder, and Hand [QuickDASH] and Constant). In the patients with rotator cuff tears, appropriate tests were used to correlate rotator cable visualization with the tear size, functional outcome, muscular fatty infiltration, and atrophy. The patients with rotator cuff tears included 25 women and 32 men (mean age,57 years; range, 39-67 years), and the volunteers included 13 women and 17 men (mean age, 56 years; range, 35-64 years). The rotator cable was identified in 77% (23 of 30) of controls and 23% (13 of 57) of patients with rotator cuff tears. In the patients, nonvisualization of the rotator cable correlated with larger tears (P tears than asymptomatic controls and was associated with a larger tear size and greater supraspinatus fatty infiltration and atrophy. Diligent assessment of the supraspinatus muscle should be done in patients with rotator cuff tears without a visible rotator cable, as the integrity of these anatomic structures may be interdependent.

  17. Anterior versus posterior, and rim-rent rotator cuff tears: prevalence and MR sensitivity

    International Nuclear Information System (INIS)

    Tuite, M.J.; Turnbull, J.R.; Orwin, J.F.

    1998-01-01

    Purpose. To determine the relative distribution of the locations of rotator cuff tears, and the sensitivity of anterior versus posterior tears on MR images. Patients and methods. We identified 110 consecutive patients who had a shoulder MR and either a partial-thickness or a small full-thickness rotator cuff tear diagnosed at arthroscopy. MR sensitivity and patient age were compared between patients with tears in the anterior and posterior halves of the cuff. In addition, in patients with partial tears less than 2 cm in diameter, an age comparison between those with tears in the critical zone and those with articular surface tears adjacent to the bony insertion (rim-rent tear) was performed. Results. The tear was centered in the anterior half of the rotator cuff in 79% of the patients younger than 36 years old, and in 89% of the patients 36 years old and over. The average age of the patients with tears in the anterior half (44 years) was not significantly different from the average age of those with posterior tears (40 years). The sensitivity of MR for anterior tears was 0.69, and for posterior tears it was 0.56. Five of the nine rim-rent tears (0.56) were interpreted correctly on the original MR report; two of the other tears were misinterpreted as intratendinous fluid but were diagnosable in retrospect. Conclusion. Even in patients less than 36 years old, most partial and small full-thickness rotator cuff tears are centered in the anterior half of the supraspinatus. Although our figure for MR sensitivity for these tears is lower than in recent articles, we found no significant difference between the sensitivity of MR for diagnosing posterior tears versus tears in the anterior half of the supraspinatus tendon. Rim-rent tears can be mistaken for intratendinous signal, and should be carefully looked for in younger patients with shoulder pain. (orig.)

  18. Validation of ultrasound imaging for Achilles entheseal fibrocartilage in bovines and description of changes in humans with spondyloarthritis.

    Science.gov (United States)

    Aydin, Sibel Zehra; Bas, Emine; Basci, Onur; Filippucci, Emilio; Wakefield, Richard J; Celikel, Cigdem; Karahan, Mustafa; Atagunduz, Pamir; Benjamin, Mike; Direskeneli, Haner; McGonagle, Dennis

    2010-12-01

    Entheseal fibrocartilage (EF) derangement is hypothesised to be pivotal to the pathogenesis of spondyloarthritis. Ultrasound is useful for visualisation of the enthesis but its role in EF visualisation is uncertain. This work aimed to demonstrate face and content validity of ultrasound for EF visualisation both by bovine histological evaluation and EF imaging in spondyloarthritis. Achilles enthesis of 18 bovine hindfeet was visualised using a MyLab 70 ultrasound machine. The presence of tissue with EF characteristics was documented and histological confirmation was performed on five randomly selected sections using Masson trichrome staining. Ultrasound of the Achilles tendon (AT) was performed in 19 patients with spondyloarthritis and 21 healthy controls (HC). The bovine EF could be visualised in all cases and seen as a thin, uncompressible, well-defined, anechoic layer between the hyperechoic bone and the hyperechoic fibrils of the enthesis both in longitudinal and transverse scans. This region corresponded to EF on histological examination. The same pattern of low signal corresponding to EF location was seen in 17/19 patients and all HC. Discontinuities of the anechoic layer around the erosions and enthesophytes were observed in the spondyloarthritis group. The thickness of the anechoic layer was not significantly different in spondyloarthritis and HC (0.5 ± 0.1 vs 0.5 ± 0.2 mm, p=0.9) whereas the thickness of the EF was greater in men (0.6 ± 0.2 vs 0.5 ± 0.1 mm; p=0.009) compared with women. Ultrasound can visualise EF of the AT insertion, which can be abnormal in cases of spondyloarthritis. This has implications for a better understanding of enthesopathy.

  19. The Effect of Polar Lipids on Tear Film Dynamics

    KAUST Repository

    Aydemir, E.

    2010-06-17

    In this paper, we present a mathematical model describing the effect of polar lipids, excreted by glands in the eyelid and present on the surface of the tear film, on the evolution of a pre-corneal tear film. We aim to explain the interesting experimentally observed phenomenon that the tear film continues to move upward even after the upper eyelid has become stationary. The polar lipid is an insoluble surface species that locally alters the surface tension of the tear film. In the lubrication limit, the model reduces to two coupled non-linear partial differential equations for the film thickness and the concentration of lipid. We solve the system numerically and observe that increasing the concentration of the lipid increases the flow of liquid up the eye. We further exploit the size of the parameters in the problem to explain the initial evolution of the system. © 2010 Society for Mathematical Biology.

  20. the effect of acetaminophen (paracetamol ) on tear production abstract

    African Journals Online (AJOL)

    LIVINGSTON

    cox-1 and cox-2 has long been known to be the mechanism of action ... effects typical of NSAIDS . Chronic excessive alcohol consumption can ... The effect of acetaminophen (paracetamol ) on the tear production of 100 young healthy subjects ...

  1. Early Vitrectomy for Vitreous Hemorrhage Associated With Retinal Tears

    NARCIS (Netherlands)

    Tan, H. Stevie; Mura, Marco; Bijl, Heico M.

    2010-01-01

    PURPOSE: To evaluate outcome of early surgery in vitreous hemorrhage, presumably associated with retinal tears. DESIGN: Retrospective, noncomparative interventional case series. METHODS: We included 40 consecutive cases in 39 patients treated with early vitrectomy for vitreous hemorrhage. Main

  2. Tearing mode dynamics and sawtooth oscillation in Hall-MHD

    Science.gov (United States)

    Ma, Zhiwei; Zhang, Wei; Wang, Sheng

    2017-10-01

    Tearing mode instability is one of the most important dynamic processes in space and laboratory plasmas. Hall effects, resulted from the decoupling of electron and ion motions, could cause the fast development and perturbation structure rotation of the tearing mode and become non-negligible. We independently developed high accuracy nonlinear MHD code (CLT) to study Hall effects on the dynamic evolution of tearing modes with Tokamak geometries. It is found that the rotation frequency of the mode in the electron diamagnetic direction is in a good agreement with analytical prediction. The linear growth rate increases with increase of the ion inertial length, which is contradictory to analytical solution in the slab geometry. We further find that the self-consistently generated rotation largely alters the dynamic behavior of the double tearing mode and the sawtooth oscillation. National Magnetic Confinement Fusion Science Program of China under Grant No. 2013GB104004 and 2013GB111004.

  3. Progression from calcifying tendinitis to rotator cuff tear

    Energy Technology Data Exchange (ETDEWEB)

    Gotoh, Masafumi; Higuchi, Fujio; Suzuki, Ritsu; Yamanaka, Kensuke [Department of Orthopaedic Surgery, Medical Center of Kurume University, 155-1 Kokubu-machi, Kurume City, Fukuoka 839-0862 (Japan)

    2003-02-01

    This report documents the clinical, radiographic and histologic findings in a 46-year-old man with calcifying tendinitis in his left shoulder which progressed to rotator cuff tear. The patient had a 1-year history of repeated calcifying tendinitis before being referred to our hospital. On the initial visit, radiographs and magnetic resonance imaging (MRI) revealed calcium deposition localized in the supraspinatus tendon without apparent tear. Three months after the first visit, MRI revealed a partial-thickness rotator cuff tear at the site of calcium deposition. Surgical and histologic findings demonstrated that calcium deposition was the cause of cuff rupture. To our knowledge, based on a review of the English literature, this is the first case report in which the progression from calcifying tendinitis to rotator cuff tear has been serially observed. (orig.)

  4. Progression from calcifying tendinitis to rotator cuff tear

    International Nuclear Information System (INIS)

    Gotoh, Masafumi; Higuchi, Fujio; Suzuki, Ritsu; Yamanaka, Kensuke

    2003-01-01

    This report documents the clinical, radiographic and histologic findings in a 46-year-old man with calcifying tendinitis in his left shoulder which progressed to rotator cuff tear. The patient had a 1-year history of repeated calcifying tendinitis before being referred to our hospital. On the initial visit, radiographs and magnetic resonance imaging (MRI) revealed calcium deposition localized in the supraspinatus tendon without apparent tear. Three months after the first visit, MRI revealed a partial-thickness rotator cuff tear at the site of calcium deposition. Surgical and histologic findings demonstrated that calcium deposition was the cause of cuff rupture. To our knowledge, based on a review of the English literature, this is the first case report in which the progression from calcifying tendinitis to rotator cuff tear has been serially observed. (orig.)

  5. 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.

  6. 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

  7. MR imaging of delamination tears of the rotator cuff tendons

    International Nuclear Information System (INIS)

    Walz, Daniel M.; Chen, Steven; Miller, Theodore T.; Hofman, Josh

    2007-01-01

    The objective was to describe the imaging appearances and location of delamination tears of the rotator cuff tendons on non-contrast conventional MR imaging. This study was reviewed and approved by our Institutional Review Board. The reports of 548 consecutive MR examinations of the shoulder were reviewed, looking for mention or description of delamination tears of the rotator cuff. The images of the identified cases were then reviewed by two radiologists to confirm the findings. Correlation with surgical and arthroscopic information was then performed. Delamination tears were defined as horizontal retraction of either the bursal or articular surface of the tendon, manifest as thickening of the torn retracted edge, and/or interstitial splitting of the tendon, manifest as fluid-like high signal intensity on fat-suppressed T2-weighted oblique coronal images. Fourteen cases of delamination tears were identified in 13 patients. Ten of the cases involved the supraspinatus tendon, all with articular surface involvement. Nine of these supraspinatus cases were isolated tears and one occurred as part of a full thickness tear. All 10 of these supraspinatus cases showed medial retraction of the articular surface of the tendon, with thickening of the retracted edge, and 5 of the 10 had a demonstrable horizontal cleft in the interstitium. Four cases involved the subscapularis tendon, with articular surface disruption in three and pure interstitial delamination in one. Medial subluxation of the tendon of the long head of the biceps was present in all four cases. No delamination tears occurred on the bursal surface. Only three of the 14 shoulders underwent surgical repair with one confirmation of supraspinatus delamination, one confirmation of a subscapularis tear that had become a full thickness tear 10 months after initial imaging and another interstitial subscapularis delamination that was not identified arthroscopically. Delamination tears occur most often in the

  8. MR imaging of delamination tears of the rotator cuff tendons

    Energy Technology Data Exchange (ETDEWEB)

    Walz, Daniel M.; Chen, Steven [North Shore University Hospital, Department of Radiology, Manhasset, NY (United States); Miller, Theodore T. [Hospital for Special Surgery, Department of Radiology and Imaging, New York, NY (United States); Hofman, Josh [Long Island Jewish Medical Center, New Hyde Park, NY (United States)

    2007-05-15

    The objective was to describe the imaging appearances and location of delamination tears of the rotator cuff tendons on non-contrast conventional MR imaging. This study was reviewed and approved by our Institutional Review Board. The reports of 548 consecutive MR examinations of the shoulder were reviewed, looking for mention or description of delamination tears of the rotator cuff. The images of the identified cases were then reviewed by two radiologists to confirm the findings. Correlation with surgical and arthroscopic information was then performed. Delamination tears were defined as horizontal retraction of either the bursal or articular surface of the tendon, manifest as thickening of the torn retracted edge, and/or interstitial splitting of the tendon, manifest as fluid-like high signal intensity on fat-suppressed T2-weighted oblique coronal images. Fourteen cases of delamination tears were identified in 13 patients. Ten of the cases involved the supraspinatus tendon, all with articular surface involvement. Nine of these supraspinatus cases were isolated tears and one occurred as part of a full thickness tear. All 10 of these supraspinatus cases showed medial retraction of the articular surface of the tendon, with thickening of the retracted edge, and 5 of the 10 had a demonstrable horizontal cleft in the interstitium. Four cases involved the subscapularis tendon, with articular surface disruption in three and pure interstitial delamination in one. Medial subluxation of the tendon of the long head of the biceps was present in all four cases. No delamination tears occurred on the bursal surface. Only three of the 14 shoulders underwent surgical repair with one confirmation of supraspinatus delamination, one confirmation of a subscapularis tear that had become a full thickness tear 10 months after initial imaging and another interstitial subscapularis delamination that was not identified arthroscopically. Delamination tears occur most often in the

  9. Threshold condition for nonlinear tearing modes in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Zabiego, M.F. [Association Euratom-CEA, Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Callen, J.D. [Wisconsin Univ., Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics

    1996-04-01

    Low-mode-number tearing mode nonlinear evolution is analyzed emphasizing the need for a threshold condition, to account for observations in tokamaks. The discussion is illustrated by two models recently introduced in the literature. Introducing a threshold condition in the tearing mode stability analysis is found to reveal some bifurcation points and thus domains of intrinsic stability in the island dynamics operational space. (author). 19 refs.

  10. Predictive MRI correlates of lesser metatarsophalangeal joint plantar plate tear

    Energy Technology Data Exchange (ETDEWEB)

    Umans, Rachel L. [Cornell University Medical College, New York, NY (United States); Umans, Benjamin D. [Harvard University, Cambridge, MA (United States); Umans, Hilary [Albert Einstein College of Medicine, Bronx, NY (United States); Lenox Hill Radiology and Imaging Associates, New York, NY (United States); Elsinger, Elisabeth [Albert Einstein College of Medicine, Bronx, NY (United States); Montefiore Medical Center, Bronx, NY (United States)

    2016-07-15

    To identify correlated signs on non-enhanced MRI that might improve diagnostic detection of plantar plate (PP) tear. We performed an IRB-approved, HIPAA-compliant retrospective analysis of 100 non-contrast MRI (50 PP tear, 50 controls). All were anonymized, randomized, and reviewed; 20 were duplicated to assess consistency. One musculoskeletal radiologist evaluated qualitative variables. A trained non-physician performed measurements. Consistency and concordance were assessed. Pearson's Chi-square test was used to test the correlation between qualitative findings and PP tear status. Correlation between measurements and PP status was assessed using t tests and Wilcoxon's rank-sum test (p values < 0.05 considered significant). Classification and regression trees were utilized to identify attributes that, taken together, would consistently distinguish PP tear from controls. Quantitative measurements were highly reproducible (concordance 0.88-0.99). Elevated 2nd MT protrusion, lesser MT supination and rotational divergence of >45 between the 1st-2nd MT axis correlated with PP tear. Pericapsular soft tissue thickening correlated most strongly with PP tear, correctly classifying 95 % of cases and controls. Excluding pericapsular soft tissue thickening, sequential assessment of 2nd toe enthesitis, 2nd flexor tendon subluxation, and splaying of the second and third toes accurately classified PP status in 92 %. Pericapsular soft tissue thickening most strongly correlated with PP tear. For cases in which it might be difficult to distinguish pericapsular fibrosis from neuroma, sequential assessment of 2nd toe enthesitis, flexor tendon subluxation and splaying of the 2nd and 3rd toe is most helpful for optimizing accurate diagnosis of PP tear. (orig.)

  11. Review of tearing mode stabilization by RF power in tokamaks

    International Nuclear Information System (INIS)

    Giruzzi, G.; Zabiego, M.; Zohm, H.

    1999-01-01

    Control of tearing modes by means of heating and current drive inside the magnetic islands is one of the most important applications of RF power in tokamak reactors. The theoretical basis of this concept is reviewed, focusing on aspects related to RF-plasma interaction. Applications to the stabilization of neoclassical tearing modes in ITER by Electron Cyclotron Current Drive are presented to illustrate the basic physical dependences. The most significant experimental results and prospects for future applications are also discussed

  12. Saturated tearing modes in tokamaks. Renewal proposal, progress report

    International Nuclear Information System (INIS)

    Bateman, G.

    1984-01-01

    We have completed a computer code (GTOR) implementing our quasilinear method for determining saturated tearing mode magnetic island widths in axisymmetric toroidal plasmas. With this code we have surveyed the effect of current profile, aspect ratio and plasma elongation on saturated tearing modes. Current peaking within the islands is found to have a particularly large effect. In support of this research, we have developed a direct method for computing Hamada coordinates from harmonics of the inverse Grad-Shafranov equation

  13. Threshold condition for nonlinear tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Zabiego, M.F.; Callen, J.D.

    1996-04-01

    Low-mode-number tearing mode nonlinear evolution is analyzed emphasizing the need for a threshold condition, to account for observations in tokamaks. The discussion is illustrated by two models recently introduced in the literature. Introducing a threshold condition in the tearing mode stability analysis is found to reveal some bifurcation points and thus domains of intrinsic stability in the island dynamics operational space. (author)

  14. 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.

  15. Medialized repair for retracted rotator cuff tears.

    Science.gov (United States)

    Kim, Young-Kyu; Jung, Kyu-Hak; Won, Jun-Sung; Cho, Seung-Hyun

    2017-08-01

    The purpose of this study was to evaluate the functional outcomes of medialized rotator cuff repair and the continuity of repaired tendon in chronic retracted rotator cuff tears. Thirty-five consecutive patients were selected from 153 cases that underwent arthroscopic rotator cuff repair for more than medium-sized posterosuperior rotator cuff tears between July 2009 and July 2012 performed with the medialized repair. All cases were available for at least 2 years of postoperative follow-up. The visual analog scale of pain, muscle strength, Constant score, American Shoulder and Elbow Surgeons (ASES) score, and University of California-Los Angeles score were evaluated. At the final follow-up, all clinical outcomes were significantly improved. The visual analog scale score for pain improved from 6 ± 1 preoperatively to 2 ± 1 postoperatively. The range of motion increased from preoperatively to postoperatively: active forward elevation, from 134° ± 49° to 150° ± 16°; active external rotation at the side, from 47° ± 15° to 55° ± 10°; and active internal rotation, from L3 to L1. The shoulder score also improved: Constant score, from 53.5 ± 16.7 to 79 ± 10; American Shoulder and Elbow Surgeons score, from 51 ± 15 to 82 ± 8; and University of California-Los Angeles score, from 14 ± 4 to 28 ± 4. The retear cases at the final follow-up were 6 (17%). Medialized repair may be useful in cases in which anatomic bone-to-tendon repair would be difficult because of the excessive tension of the repaired tendon and a torn tendon that does not reach the anatomic insertion. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  16. 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)

  17. 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.

  18. [Evaluation of chemokines in tears of patients with infectious keratitis].

    Science.gov (United States)

    Hori, Shinsuke; Shoji, Jun; Inada, Noriko; Sawa, Mitsuru

    2013-02-01

    To investigate the chemokine profile in tears of patients with infectious keratitis. Subjects were 32 eyes of 16 patients with infectious keratitis and 5 eyes of 5 healthy volunteers as a control. The patients with infectious keratitis were classified into two groups of eyes: 10 with bacterial keratitis and 6 with Acanthamoeba keratitis. Tear fluid was obtained from both eyes of the patients with infectious keratitis and from the right eyes of the control subjects using filter paper. Chemokine concentration (unit: Odu/mm2) and its profile in tears was analyzed using an antibody-array. In terms of chemokine profile in the bacterial keratitis group, the expression volume of interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) in the diseased eyes was significantly higher than in the healthy eyes (p tears of the Acanthamoeba keratitis group. Regarding the chemokine ratio, the IL-8/MEC ratio in the diseased eyes of the Pseudomonas keratitis group and the MCP-1/IL-8 in the diseased eyes of the Acanthamoeba keratitis group showed a significantly high level (p tears of infectious keratitis patients is useful as a clinical tear laboratory test to interpret the pathologic condition of infectious keratitis

  19. Artificially modified collagen fibril orientation affects leather tear strength.

    Science.gov (United States)

    Kelly, Susyn J; Wells, Hannah C; Sizeland, Katie H; Kirby, Nigel; Edmonds, Richard L; Ryan, Tim; Hawley, Adrian; Mudie, Stephen; Haverkamp, Richard G

    2018-07-01

    Ovine leather has around half the tear strength of bovine leather and is therefore not suitable for high-value applications such as shoes. Tear strength has been correlated with the natural collagen fibril alignment (orientation index, OI). It is hypothesized that it could be possible to artificially increase the OI of the collagen fibrils and that an artificial increase in OI could increase tear strength. Ovine skins, after pickling and bating, were strained biaxially during chrome tanning. The strain ranged from 2 to 15% of the initial sample length, either uniformly in both directions by 10% or with 3% in one direction and 15% in the other. Once tanned, the leather tear strengths were measured and the collagen fibril orientation was measured using synchrotron-based small-angle X-ray scattering. The OI increased as a result of strain during tanning from 0.48 to 0.79 (P = 0.001) measured edge-on and the thickness-normalized tear strength increased from 27 to 43 N mm -1 (P leather was strained 10% in two orthogonal directions. This is evidence to support a causal relationship between high OI (measured edge-on), highly influenced by thickness, and tear strength. It also provides a method to produce stronger leather. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  20. On tear film breakup (TBU): dynamics and imaging.

    Science.gov (United States)

    Braun, Richard J; Driscoll, Tobin A; Begley, Carolyn G; King-Smith, P Ewen; Siddique, Javed I

    2018-06-13

    We report the results of some recent experiments to visualize tear film dynamics. We then study a mathematical model for tear film thinning and tear film breakup (TBU), a term from the ocular surface literature. The thinning is driven by an imposed tear film thinning rate which is input from in vivo measurements. Solutes representing osmolarity and fluorescein are included in the model. Osmolarity causes osmosis from the model ocular surface, and the fluorescein is used to compute the intensity corresponding closely to in vivo observations. The imposed thinning can be either one-dimensional or axisymmetric, leading to streaks or spots of TBU, respectively. For a spatially-uniform (flat) film, osmosis would cease thinning and balance mass lost due to evaporation; for these space-dependent evaporation profiles TBU does occur because osmolarity diffuses out of the TBU into the surrounding tear film, in agreement with previous results. The intensity pattern predicted based on the fluorescein concentration is compared with the computed thickness profiles; this comparison is important for interpreting in vivo observations. The non-dimensionalization introduced leads to insight about the relative importance of the competing processes; it leads to a classification of large vs small TBU regions in which different physical effects are dominant. Many regions of TBU may be considered small, revealing that the flow inside the film has an appreciable influence on fluorescence imaging of the tear film.

  1. Comparison of non-invasive tear film stability measurement techniques.

    Science.gov (United States)

    Wang, Michael Tm; Murphy, Paul J; Blades, Kenneth J; Craig, Jennifer P

    2018-01-01

    Measurement of tear film stability is commonly used to give an indication of tear film quality but a number of non-invasive techniques exists within the clinical setting. This study sought to compare three non-invasive tear film stability measurement techniques: instrument-mounted wide-field white light clinical interferometry, instrument-mounted keratoscopy and hand-held keratoscopy. Twenty-two subjects were recruited in a prospective, randomised, masked, cross-over study. Tear film break-up or thinning time was measured non-invasively by independent experienced examiners, with each of the three devices, in a randomised order, within an hour. Significant correlation was observed between instrument-mounted interferometric and keratoscopic measurements (p 0.05). Tear film stability values obtained from the hand-held device were significantly shorter and demonstrated narrower spread than the other two instruments (all p 0.05). Good clinical agreement exists between the instrument-mounted interferometric and keratoscopic measurements but not between the hand-held device and either of the instrument-mounted techniques. The results highlight the importance of specifying the instrument employed to record non-invasive tear film stability. © 2017 Optometry Australia.

  2. 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

  3. Effects of amino acids enriched tears substitutes on the cornea of patients with dysfunctional tear syndrome.

    Science.gov (United States)

    Aragona, Pasquale; Rania, Laura; Roszkowska, Anna M; Spinella, Rosaria; Postorino, Elisa; Puzzolo, Domenico; Micali, Antonio

    2013-09-01

    To evaluate the effect of aminoacid enriched artificial tears on the ocular surface of patients with dysfunctional tear syndrome (DTS). Forty patients were divided into two groups: group 1 treated for 90 days with sodium hyaluronate (SH) 0.15% 1 drop × 5 times/day; group 2 treated for 90 days with SH 0.15% + aminoacids mixture 1 drop × 5 times/day. Symptom score questionnaire, tear break-up time (TBUT), corneal fluorescein stain, Shirmer's I test and confocal microscopy were performed at baseline and after 30 and 90 days. Confocal images underwent morphometric analysis. Both treatments improved symptoms after 1 month. Group 2 patients showed at 1 month an improvement of TBUT and corneal stain, maintained throughout the study. Also Shirmer's I test improved after 3 months. In group 1, an improvement of TBUT and corneal stain was observed after 3 months. The morphometric analysis of confocal images demonstrated at month 1 an improvement of nerve tortuosity in group 2; after 3 months both groups showed a significant improvement versus baseline. The epithelium showed, in both groups, a reduction in hyperreflective large cells starting from 1 month; the area of the cells was significantly reduced after 3 months, with a significant higher reduction in group 2. The perineural stromal opacity was significantly increased after 3 months, particularly in group 2. This is the first study addressing corneal changes after amino acids administration in a DTS population. The treatment with amino acids enriched SH can be considered a useful tool in the treatment of DTS. © 2013 The Authors Acta Ophthalmologica © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by Blackwell Publishing Ltd.

  4. 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.)

  5. 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.)

  6. Linear neoclassical tearing mode in tokamaks

    International Nuclear Information System (INIS)

    Shaing, K. C.

    2007-01-01

    The growth rate of linear tearing modes in tokamaks is calculated including the neoclassical dissipation mechanism. It is found that when the growth rate is much smaller than the ion-ion collision frequency, the growth rate is reduced approximately by a factor of (B p /B) 2/5 from its standard value, and when the growth rate is much larger than the ion-ion collision frequency, the growth rate is reduced by a factor [√(ε)/(1.6q 2 )] 1/5 . Here, B p is the poloidal magnetic field strength, B is the magnetic field strength, ε is the inverse aspect ratio, and q is the safety factor. The width of the resistive layer is broadened when compared to that of the standard theory. In both limits, the growth rate and the resistive layer width only depend on B p and are independent of B. The growth rates in the plateau regime and for the inertia dominant modes are also presented

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. The 'bridging sign', a MR finding for combined full-thickness tears of the subscapularis tendon and the supraspinatus tendon

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jin Young [Dept. of Radiology, Saint Paul' s Hospital, The Catholic Univ. of Korea, Seoul (Korea, Republic of); Yoon, Young Cheol; Cha, Dong Ik [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan Univ, School of Medicine, Seoul (Korea, Republic of)], e-mail: ycyoon@skku.edu; Yoo, Jae-Chul [Dept. of Orthopedic Surgery, Samsung Medical Center, Sungkyunkwan Univ. School of Medicine, Seoul (Korea, Republic of); Jung, Jee Young [Dept. of Radiology, School of Medicine, Chung-Ang Univ., Seoul (Korea, Republic of)

    2013-02-15

    Background: In daily practice, we discovered one of the secondary magnetic resonance (MR) findings of the subscapularis (SSC) tendon tear, the 'bridging sign', which has not been previously described. Purpose: To describe the 'bridging sign' on shoulder MR imaging and its radiological and clinical significance in patients with SSC tendon tear. Material and Methods: Twenty-nine patients who had undergone shoulder arthroscopy and had full-thickness tear of the subscapularis tendon were enrolled. The medical records of the 29 patients were retrospectively reviewed for the duration of shoulder pain, rotator cuff tears, and associated arthroscopic findings: biceps tendon abnormality and superior glenoid labral tear. Then, preoperative shoulder MR images were retrospectively reviewed for the presence or absence of the 'bridging sign' and associated MR findings: periarticular fluid and fatty atrophy of the supraspinatus and subscapularis muscles. The type of rotator cuff tear associated with the 'bridging sign' was assessed and the sensitivity, specificity, and accuracy of the 'bridging sign' for the diagnosis of a certain type of rotator cuff tear were calculated. Associated arthroscopic and MR findings and mean duration of the shoulder pain between the patients with and without the 'bridging sign' were compared. Results: The 'bridging sign' was seen in 17 of 29 patients and corresponded to a complex of the torn and superomedially retracted subscapularis tendon, coracohumeral ligament, and superior glenohumeral ligament, adhered to the anterior margin of the torn supraspinatus (SSP) tendon on arthroscopy. All patients with the 'bridging sign' had combined full-thickness tear (FTT) of the cranial 1/2 portion of the subscapularis tendon and anterior 1/2 portion of the SSP tendon. The sensitivity, specificity, and accuracy of the 'bridging sign' for the diagnosis of combined FTTs of

  13. Determination of water-soluble and fat-soluble vitamins in tears and blood serum of infants and parents by liquid chromatography/mass spectrometry.

    Science.gov (United States)

    Khaksari, Maryam; Mazzoleni, Lynn R; Ruan, Chunhai; Kennedy, Robert T; Minerick, Adrienne R

    2017-02-01

    Tears serve as a viable diagnostic fluid with advantages including less invasive sample to collect and less complex to prepare for analysis. Several water-soluble and fat-soluble vitamins were detected and quantified in human tears and compared with blood serum levels. Samples from 15 family pairs, each pair consisting of a four-month-old infant and one parent were analyzed; vitamin concentrations were compared between tears and blood serum for individual subjects, between infants and parents, and against self-reported dietary intakes. Water-soluble vitamins B 1 , B 2 , B 3 (nicotinamide), B 5 , B 9 and fat-soluble vitamin E (α-tocopherol) were routinely detected in tears and blood serum while fat-soluble vitamin A (retinol) was detected only in blood serum. Water-soluble vitamin concentrations measured in tears and blood serum of single subjects were comparable, while higher concentrations were measured in infants compared to their parents. Fat-soluble vitamin E concentrations were lower in tears than blood serum with no significant difference between infants and parents. Serum vitamin A concentrations were higher in parents than infants. Population trends were compiled and quantified using a cross correlation factor. Strong positive correlations were found between tear and blood serum concentrations of vitamin E from infants and parents and vitamin B 3 concentrations from parents, while slight positive correlations were detected for infants B 3 and parents B 1 and B 2 concentrations. Correlations between infants and parents were found for the concentrations of B 1 , B 2 , B 3 , and E in tears, and the concentrations of B 2, A, and E in blood serum. Stronger vitamin concentration correlations were found between infants and parents for the breast-fed infants, while no significant difference was observed between breast-fed and bottle-fed infants. This work is the first to demonstrate simultaneous vitamin A, B, and E detection and to quantify correlations between

  14. Glycan involvement in the adhesion of Pseudomonas aeruginosa to tears.

    Science.gov (United States)

    Kautto, Liisa; Nguyen-Khuong, Terry; Everest-Dass, Arun; Leong, Andrea; Zhao, Zhenjun; Willcox, Mark D P; Packer, Nicolle H; Peterson, Robyn

    2016-04-01

    The human eye is constantly bathed by tears, which protect the ocular surface via a variety of mechanisms. The O-linked glycans of tear mucins have long been considered to play a role in binding to pathogens and facilitating their removal in the tear flow. Other conjugated glycans in tears could similarly contribute to pathogen binding and removal but have received less attention. In the work presented here we assessed the contribution of glycan moieties, in particular the protein attached N-glycans, presented by the broad complement of tear proteins to the adhesion of the opportunistic pathogen Pseudomonas aeruginosa, a leading cause of microbial keratitis and ulceration of the cornea. Our adhesion assay involved immobilising the macromolecular components of tears into the wells of a polyvinyl difluoride (PVDF) microtitre filter plate and probing the binding of fluorescently labelled bacteria. Three P. aeruginosa strains were studied: a cytotoxic strain (6206) and an invasive strain (6294) from eye infections, and an invasive strain (320) from a urinary tract infection (UTI). The ocular isolates adhered two to three times more to human tears than to human saliva or porcine gastric mucin, suggesting ocular niche-specific adaptation. Support for the role of the N-glycans carried by human tear proteins in the binding and removal of P. aeruginosa from the eye was shown by: 1) pre-incubation of the bacteria with free component sugars, galactose, mannose, fucose and sialyl lactose (or combination thereof) inhibiting adhesion of all the P. aeruginosa strains to the immobilised tear proteins, with the greatest inhibition of binding of the ocular cytotoxic 6206 and least for the invasive 6294 strain; 2) pre-incubation of the bacteria with N-glycans released from the commercially available human milk lactoferrin, an abundant protein that carries N-linked glycans in tears, inhibiting the adhesion to tears of the ocular bacteria by up to 70%, which was significantly more

  15. Supraspinatus tendon tears: comparison of 3D US and MR arthrography with surgical correlation

    International Nuclear Information System (INIS)

    Kang, Chang Ho; Kim, Sam Soo; Kim, Jung Hyuk; Chung, Kyoo Byung; Kim, Yun Hwan; Oh, Yu-Whan; Jeong, Woong-Kyo; Kim, Baek Hyun

    2009-01-01

    The objective of the study was to compare the diagnostic reliability of 3D US with MR arthrography in diagnosing supraspinatus tendon tears, with arthroscopic findings used as the standard. In a prospective study 50 patients who later underwent arthroscopic surgery of the rotator cuff were examined pre-operatively by 3D US with MR arthrography. The presence or absence of a full- or partial-thickness supraspinatus tendon tear and the tear size as demonstrated by each imaging and arthroscopy was recorded. The tear size was divided into three grades: small ( 3 cm). The arthroscopic diagnosis was a full-thickness tear in 40 patients, partial-thickness tears in 5, and intact supraspinatus tendon in 5. 3D US correctly diagnosed 35 out of 40 full-thickness tears and MR arthrography 39 out of 40 full-thickness tears. Regarding partial-thickness tears, 3D US underestimated 2 cases as no tear and overestimated 1 case as a full-thickness tear. MR arthrography underestimated 1 case as a partial-thickness tear and overestimated 2 cases as full-thickness and partial-thickness tears respectively. 3D US and MR arthrography yield a sensitivity for full-thickness tears of 87.5% and 97.5% with specificity of 90.0% and 90.0%. Based on the grading system, 3D US measurements correctly predicted the tear size of 23 (65.7%) of the 35 full-thickness tears and MR arthrography 30 (75.0%) of the 39 full-thickness tears. Three-dimensional ultrasound seems to be a promising imaging modality comparable to MR arthrography for the assessment of the supraspinatus tendon tears. (orig.)

  16. Supraspinatus tendon tears: comparison of 3D US and MR arthrography with surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Chang Ho [Kangwon National University Hospital, Department of Radiology, Kangwon-do (Korea); Korea University Anam Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea); Kim, Sam Soo [Kangwon National University Hospital, Department of Radiology, Kangwon-do (Korea); Kim, Jung Hyuk; Chung, Kyoo Byung; Kim, Yun Hwan; Oh, Yu-Whan [Korea University Anam Hospital, Korea University College of Medicine, Department of Radiology, Seoul (Korea); Jeong, Woong-Kyo [Korea University Anam Hospital, Korea University College of Medicine, Orthopaedic Surgery, Seoul (Korea); Kim, Baek Hyun [Korea University Ansan Hospital, Korea University College of Medicine, Department of Radiology, Ansan City (Korea)

    2009-11-15

    The objective of the study was to compare the diagnostic reliability of 3D US with MR arthrography in diagnosing supraspinatus tendon tears, with arthroscopic findings used as the standard. In a prospective study 50 patients who later underwent arthroscopic surgery of the rotator cuff were examined pre-operatively by 3D US with MR arthrography. The presence or absence of a full- or partial-thickness supraspinatus tendon tear and the tear size as demonstrated by each imaging and arthroscopy was recorded. The tear size was divided into three grades: small (<1 cm), medium (1-3 cm), and large (>3 cm). The arthroscopic diagnosis was a full-thickness tear in 40 patients, partial-thickness tears in 5, and intact supraspinatus tendon in 5. 3D US correctly diagnosed 35 out of 40 full-thickness tears and MR arthrography 39 out of 40 full-thickness tears. Regarding partial-thickness tears, 3D US underestimated 2 cases as no tear and overestimated 1 case as a full-thickness tear. MR arthrography underestimated 1 case as a partial-thickness tear and overestimated 2 cases as full-thickness and partial-thickness tears respectively. 3D US and MR arthrography yield a sensitivity for full-thickness tears of 87.5% and 97.5% with specificity of 90.0% and 90.0%. Based on the grading system, 3D US measurements correctly predicted the tear size of 23 (65.7%) of the 35 full-thickness tears and MR arthrography 30 (75.0%) of the 39 full-thickness tears. Three-dimensional ultrasound seems to be a promising imaging modality comparable to MR arthrography for the assessment of the supraspinatus tendon tears. (orig.)

  17. Hot tearing susceptibility of binary Mg–Y alloy castings

    International Nuclear Information System (INIS)

    Wang, Zhi; Huang, Yuanding; Srinivasan, Amirthalingam; Liu, Zheng; Beckmann, Felix; Kainer, Karl Ulrich; Hort, Norbert

    2013-01-01

    Highlights: ► Quantitatively and qualitatively assessing hot tearing susceptibility for different alloys. ► Monitoring the hot tearing propagation process. ► Detecting the hot tearing initiation/onset temperature. ► Recording the stress and strain evolution during the casting solidification and the subsequent cooling. - Abstract: The influence of Y content on the hot tearing susceptibility (HTS) of binary Mg–Y alloys has been predicted using thermodynamic calculations based on Clyne and Davies model. The calculated results are compared with experimental results determined using a constrained rod casting (CRC) apparatus with a load cell and data acquisition system. Both thermodynamic calculations and experimental measurements indicate that the hot tearing susceptibility as a function of Y content follows the “λ” shape. The experimental results show that HTS first increases with increase in Y content, reaches the maximum at about 0.9 wt.%Y and then decreases with further increase the Y content. The maximum susceptibility observed in Mg–0.9 wt.%Y alloy is attributed to its coarsened columnar microstructure, large solidification range and small amount of eutectic at the time of hot tearing. The initiation of hot cracks is monitored during CRC experiments. It corresponds to a drop in load increment on the force curves. The critical solid fractions at which the hot cracks are initiated are in the range from 0.9 to 0.99. It is also found that it decreases with increasing the content of Y. The hot cracks propagate along the dendritic or grain boundaries through the interdendritic separation or tearing of interconnected dendrites. Some of the formed cracks are possible to be healed by the subsequent refilling of the remained liquids

  18. 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.)

  19. 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.)

  20. 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.

  1. 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

  2. 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...

  3. Acetabular labral tears in patients with sports injury.

    Science.gov (United States)

    Kang, Chan; Hwang, Deuk-Soo; Cha, Soo-Min

    2009-12-01

    We wanted to investigate acetabular labral tears and their correlation with femoroacetabular impingement in patients with sports injury. Among 111 patients who were diagnosed with the acetabular labral tears after arthroscopic treatment from January 2004 to December 2007, we selected 41 patients with sports injury. There were 12 cases of Taekwondo injury, 5 of golf injury, 4 of soccer injury, 3 of gymnastics injury, 2 of Hapkido injury, 2 of aerobics injury, 2 of rock-climbing injury, 2 of fitness training injury and 9 of other sports injuries. We checked the subtypes of acetabular labral tears and the accompanying femoroacetabular impingement. For the cases with accompanying femoroacetabular impingement, we investigated the subtypes according to the types of sports, gender and age. At last follow-up, we checked the Harris Hip Score (HHS), the Hip Outcome Score (HOS) sports scale and the percentage of patients who returned to their sports activity. The average age of symptomatic onset was 26 years (range, 12 to 65 years). The ratio of males to females was 29 : 12. An average duration of the hip pain was 17 months (range, 1 to 60 months). The degenerative type of acetabular labral tears was the most prevalent with 32 cases (78%), and there were 9 cases (22%) of the partial tear type. Thirty cases (73%) were accompanied by femoroacetabular impingement. The average age of the 23 cases (56%) of the cam-type was 23 years (range, 12 to 48 years), and it was more likely to occur in men (87%) and for people practicing martial arts such as Taekwondo or Hapkido. An average age of the 5 cases (12%) of the pincer-type was 26 (range, 16 to 43 years), it usually occurred in women (60%) and for non-martial arts such as golf and gymnastics. There were 2 cases of the mixed type (cam + pincer-type). At 27 months follow-up, the HHS was 61 to 92 points, the HOS sports scale increased 43 to 75%, and the rate of returning to sports was 71%. In spite of the early expression of symptoms

  4. Immunoglobulin Concentration in Tears of Contact Lens Wearers

    Science.gov (United States)

    Maurya, Rajendra P.; Bhushan, Prashant; Singh, Virendra P.; Singh, Mahendra K.; Kumar, Prakash; Bhatia, Ravindra P.S.; Singh, Usha

    2014-01-01

    Purpose: To evaluate changes in the concentration of tear immunoglobulins in contact lens wearers. Methods: A total of 45 cases including 23 contact lens wearers (43 eyes) and 22 age and sex matched healthy controls having no ocular pathology were studied for immunoglobulins (IgA, IgG, IgM) in their tears by single radial immunodiffusion method. Results: Most of the cases used soft (56.6%) and semi-soft gas permeable (30.4%) contact lenses. Tear IgM was detected in only 17.4% and tear IgG in 43.6% of contact lens wearers, while in controls IgG was detected in 9.1% but none of the controls had IgM. There was a significant rise in total tear IgA (13.17 ± 4.44 mg/dl) in contact lens wearer as compared to controls (8.93 ± 3.79 mg/dl). Rise of tear IgA was more in symptomatic patients (15.38 ± 5.28 mg/dl) and in those wearing hard (19.73 ± 5.43 mg/dl) and semi-soft contact lenses (13.31 ± 5.43 mg/dl). A significant increase in tear IgA was noticed in subjects wearing lenses for >3 years (15.69 ± 5.39 mg/dl). About 43.4% of lens wearers were symptomatic and 80% of their lenses showed deposits and/or haziness. All cases with IgM in tear were symptomatic. Conclusion: The relation of immunoglobulin concentration with increasing duration of wear and material of contact lens shows that tear immunoglobulin rise accrues due to mechanical stimulation, hence contact lenses should not be used for a long period and lenses of hard nature should be discouraged. The maintenance, cleaning and deproteinization of the lenses are of high importance to avoid immunostimulation. PMID:25667732

  5. Tearing resistance of some co-polyester sheets

    International Nuclear Information System (INIS)

    Kim, Ho Sung; Karger-Kocsis, Jozsef

    2004-01-01

    A three-zone model consisting of initial, evolutionary and stabilised plastic zones for tearing resistance was proposed for polymer sheets. An analysis with the model, based on the essential work of fracture (EWF) approach, was demonstrated to be capable for predicting specific total work of fracture along the tear path across all the plastic zones although accuracy of specific essential work of fracture is subject to improvement. Photo-elastic images were used for identification of plastic deformation sizes and profiles. Fracture mode change during loading was described in relation with the three zones. Tearing fracture behaviour of extruded mono- and bi-layer sheets of different types of amorphous co-polyesters and different thicknesses was investigated. Thick material exhibited higher specific total work of tear fracture than thin mono-layer sheet in the case of amorphous polyethylene terephthalate (PET). This finding was explained in terms of plastic zone size formed along the tear path, i.e., thick material underwent larger plastic deformation than thin material. When PET and polyethylene terephthalate glycol (PETG) were laminated with each other, specific total work of fracture of the bi-layer sheets was not noticeably improved over that of the constituent materials

  6. Contact Lens-Induced Discomfort and Protein Changes in Tears.

    Science.gov (United States)

    Masoudi, Simin; Stapleton, Fiona Jane; Willcox, Mark Duncan Perry

    2016-08-01

    Ocular discomfort is among the main causes of contact lens wear discontinuation. This study investigated the association between subjective ocular comfort ratings and diurnal changes in tear protein concentrations with and without contact lens wear. The study was a prospective, open-label, single-group two-staged investigation. Basal tears were collected from 30 experienced contact lens wearers twice a day (morning and evening) using a noninvasive method without lens wear (stage 1) and during wear of Etafilcon A contact lenses (stage 2) for 7 to 10 days. Subjects rated their ocular comfort on a scale of 1 to 100 (with 100 as extremely comfortable) at each time of tear collection. Tears were analyzed using liquid quadrupole mass spectrometry in conjunction with selected reaction monitoring (SRM) method. End-of-day comfort was reduced when wearing lenses (87.8 ± 14.3 AM vs. 79.2 ± 16.6 PM) compared to no lens wear (88.3 ± 12.6 AM vs. 84.7 ± 13.3 PM) (AM vs. PM, p tears (p < 0.05, r = -0.29). Only the absolute concentration of prolactin-induced protein correlated with subjective comfort ratings. Taking into consideration that prolactin-induced protein can be associated with disruption in water transport in lacrimal glands, our findings may indicate that changes to aqueous secretion are associated with contact lens discomfort.

  7. Postanaesthetic tear production and ocular irritation in cats.

    Science.gov (United States)

    Peche, N; Köstlin, R; Reese, S; Pieper, K

    2015-01-01

    General anaesthesia significantly reduces tear production and normal values are not immediately re-established on ending anaesthesia. Therefore, adequate protection of the cornea has to be assured during the perianaesthetic period. There are various methods available, including taping of the eyelids and the application of eye ointments, gels and drops. In human medicine studies, different formulations were found to induce signs of ocular irritation. The aim of the present study was to determine tear production in cats after general anaesthesia, and to identify possible causes of irritation. Tear production was determined in 41 cats after general anaesthesia and eyes were examined for signs of irritation. Two different anaesthetic protocols were used. To protect the cornea, an ointment and gel were applied to the right and left eyes, respectively. Postoperatively, tear production was significantly reduced for 6 hours and 18 hours in the right and left eyes, respectively. Two hours after anaesthesia, blepharospasm of the right eye was observed in 92.7% (n = 38) of the cats. In contrast, the left eye was always held open. This study demonstrated that tear production in cats is significantly decreased both during and after anaesthesia. The degree of reduction was independent of the anaesthetic protocol. Both the eye ointment and gel proved effective in protecting the corneal surface. However, eye gel use is recommended because the eye ointment consistently caused an irritation comparable to the foreign-body sensation reported in humans.

  8. Local effect of equilibrium current on tearing mode stability

    International Nuclear Information System (INIS)

    Cozzani, F.

    1985-12-01

    The local effect of the equilibrium current on the linear stability of low poloidal number tearing modes in tokamaks is investigated analytically. The plasma response inside the tearing layer is derived from fluid theory and the local equilibrium current is shown to couple to the mode dynamics through its gradient, which is proportional to the local electron temperature gradient under the approximations used in the analysis. The relevant eigenmode equations, expressing Ampere's law and the plasma quasineutrality condition, respectively, are suitably combined in a single integral equation, from which a variational principle is formulated to derive the mode dispersion relations for several cases of interest. The local equilibrium current is treated as a small perturbation of the known results for the m greater than or equal to 2 and the m = 1 tearing modes in the collisional regime, and the m greater than or equal to 2 tearing mode in the semicollisional regime; its effect is found to enhance stabilization for the m greater than or equal to 2 drift-tearing mode in the collisional regime, whereas the m = 1 growth rate is very slightly increased and the stabilizing effect of the parallel thermal conduction on the m greater than or equal to 2 mode in the semicollisional regime is slightly reduced

  9. Preference direction study of Job’s-tears ice cream

    Directory of Open Access Journals (Sweden)

    Wiwat Wangcharoen

    2007-09-01

    Full Text Available Job's-tears (Coix lachryma-jobi L. is a kind of cereal commonly used in Asia as food and medicine, but it is still not widely consumed in Thailand. Four prototype products of Job’s-tears ice cream were developed by varying 2 levels of glucose syrup (16 and 32% of Job's-tears used and coconut milk (50 and 100 % of Job's-tears used. Their sensory attribute profiles were evaluated by 3 groups of 10 selected panelists using Ratio profile test (RPT, and their acceptances, hedonic scores, were evaluated by 100 consumers. Results showed that there were significant effects of coconut milk quantity on several attributes, such as appearance (whiteness, texture (hardness, smoothness, and flavour (coconut milk aroma, sweetness, saltiness, but the effect of glucose syrup quantity was significant on hardness only. Acceptance data were analyzed by cluster analysis to find out the difference of preference directions and 3 clusters (n1 = 39, n2 = 25, n3 = 36 were found. The first cluster preferred Job's tears ice cream containing high glucose syrup and low coconut milk, whilst the second preferred high level of only one of these two ingredients, and the third preferred high level of both ingredients. External preference maps were created from RPT and acceptance data to express the preference direction of each cluster.

  10. Partial and complete tear of the anterior cruciate ligament. Direct and indirect MR signs

    International Nuclear Information System (INIS)

    Chen, W.T.; Tu, H.Y.; Chen, R.C.; Shih, T.T.F.; Shau, W.Y.

    2002-01-01

    Purpose: To analyze MR direct and indirect signs for knees with anterior cruciate ligament (ACL) partial or complete tear. Material and Methods: According to documented MR direct and indirect signs for ACL tear, we retrospectively reviewed the incidence of those signs in 15 partial ACL tear and 17 complete ACL tear patients. The findings were also compared with duration of injury (less or more than 6 weeks, as acute or chronic stages). Results: A residual straight and tight ACL fiber in at least one pulse sequence was more frequently detected in partial ACL tears. The empty notch sign, a wavy contour of ACL, bone contusion at lateral compartment and lateral meniscus posterior horn tear were significantly more frequently seen in complete tear cases. The posterior cruciate ligament angle in chronic complete ACL tear cases (109 deg ±20 deg) had a tendency to be less than in chronic partial ACL tear cases (119 deg ±18 deg). Conclusion: The empty notch sign, a wavy ACL, bone contusion, and posterior horn of lateral meniscus tears are suggestive of a complete ACL tear. A residual straight and tight ACL fiber seen in at least one image section is a helpful sign to diagnosis of partial ACL tear. In the acute ACL injury stage, a focal increase of the ACL signal intensity is more suggestive of a partial ACL tear

  11. Rotator cuff tears in children and adolescents: experience at a large pediatric hospital

    International Nuclear Information System (INIS)

    Zbojniewicz, Andrew M.; Emery, Kathleen H.; Maeder, Matthew E.; Salisbury, Shelia R.

    2014-01-01

    Prior literature, limited to small case series and case reports, suggests that rotator cuff tears are rare in adolescents. However, we have identified rotator cuff tears in numerous children and adolescents who have undergone shoulder MRI evaluation. The purpose of this study is to describe the prevalence and characteristics of rotator cuff tears in children and adolescents referred for MRI evaluation of the shoulder at a large pediatric hospital and to correlate the presence of rotator cuff tears with concurrent labral pathology, skeletal maturity and patient activity and outcomes. We reviewed reports from 455 consecutive non-contrast MRI and magnetic resonance arthrogram examinations of the shoulder performed during a 2-year period, and following exclusions we yielded 205 examinations in 201 patients (ages 8-18 years; 75 girls, 126 boys). Rotator cuff tears were classified by tendon involved, tear thickness (partial or full), surface and location of tear (when partial) and presence of delamination. We recorded concurrent labral pathology when present. Physeal patency of the proximal humerus was considered open, closing or closed. Statistical analysis was performed to evaluate for a relationship between rotator cuff tears and degree of physeal patency. We obtained patient activity at the time of injury, surgical reports and outcomes from clinical records when available. Twenty-five (12.2%) rotator cuff tears were identified in 17 boys and 7 girls (ages 10-18 years; one patient had bilateral tears). The supraspinatus tendon was most frequently involved (56%). There were 2 full-thickness and 23 partial-thickness tears with articular-side partial-thickness tears most frequent (78%). Insertional partial-thickness tears were more common (78%) than critical zone tears (22%) and 10 (43%) partial-thickness tears were delamination tears. Nine (36%) patients with rotator cuff tears had concurrent labral pathology. There was no statistically significant relationship between

  12. Rotator cuff tears in children and adolescents: experience at a large pediatric hospital

    Energy Technology Data Exchange (ETDEWEB)

    Zbojniewicz, Andrew M.; Emery, Kathleen H. [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); Maeder, Matthew E. [University of Cincinnati College of Medicine, Department of Radiology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States); Lenox Hill Hospital, Department of Radiology, New York, NY (United States); Salisbury, Shelia R. [University of Cincinnati College of Medicine, Division of Biostatistics and Epidemiology, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH (United States)

    2014-06-15

    Prior literature, limited to small case series and case reports, suggests that rotator cuff tears are rare in adolescents. However, we have identified rotator cuff tears in numerous children and adolescents who have undergone shoulder MRI evaluation. The purpose of this study is to describe the prevalence and characteristics of rotator cuff tears in children and adolescents referred for MRI evaluation of the shoulder at a large pediatric hospital and to correlate the presence of rotator cuff tears with concurrent labral pathology, skeletal maturity and patient activity and outcomes. We reviewed reports from 455 consecutive non-contrast MRI and magnetic resonance arthrogram examinations of the shoulder performed during a 2-year period, and following exclusions we yielded 205 examinations in 201 patients (ages 8-18 years; 75 girls, 126 boys). Rotator cuff tears were classified by tendon involved, tear thickness (partial or full), surface and location of tear (when partial) and presence of delamination. We recorded concurrent labral pathology when present. Physeal patency of the proximal humerus was considered open, closing or closed. Statistical analysis was performed to evaluate for a relationship between rotator cuff tears and degree of physeal patency. We obtained patient activity at the time of injury, surgical reports and outcomes from clinical records when available. Twenty-five (12.2%) rotator cuff tears were identified in 17 boys and 7 girls (ages 10-18 years; one patient had bilateral tears). The supraspinatus tendon was most frequently involved (56%). There were 2 full-thickness and 23 partial-thickness tears with articular-side partial-thickness tears most frequent (78%). Insertional partial-thickness tears were more common (78%) than critical zone tears (22%) and 10 (43%) partial-thickness tears were delamination tears. Nine (36%) patients with rotator cuff tears had concurrent labral pathology. There was no statistically significant relationship between

  13. Comparisons of the Various Partial-Thickness Rotator Cuff Tears on MR Arthrography and Arthroscopic Correlation

    International Nuclear Information System (INIS)

    Chun, Kyung Ah; Kim, Min Sung; Kim, Young Joo

    2010-01-01

    To assess the diagnostic performance of MR arthrography in the diagnosis of the various types of partial-thickness rotator cuff tears by comparing the MR imaging findings with the arthroscopic findings. The series of MR arthrography studies included 202 patients consisting of 100 patients with partial-thickness rotator cuff tears proved by arthroscopy and a control group of 102 patients with arthroscopically intact rotator cuffs, which were reviewed in random order. At arthroscopy, 54 articularsided, 26 bursal-sided, 20 both articular- and bursal-sided partial-thickness tears were diagnosed. The MR arthrographies were analyzed by two radiologists for articular-sided tears, bursal-sided tears, and both articular- and bursal-sided tears of the rotator cuff. The sensitivity and specificity of each type of partial-thickness tears were determined. Kappa statistics was calculated to determine the interand intra-observer agreement of the diagnosis of partial-thickness rotator cuff tears. The sensitivity and specificity of the various types of rotator cuff tears were 85% and 90%, respectively for articular-sided tears, 62% and 95% for bursal- sided tears, as well as 45% and 99% for both articular- and bursal-sided tears. False-negative assessments were primarily observed in the diagnosis of bursal-sided tears. Conversely, both articular- and bursal-sided tears were overestimated as full-thickness tears. Inter-observer agreement was excellent for the diagnosis of articular-sided tears (k = 0.70), moderate (k = 0.59) for bursal-sided tears, and fair (k = 0.34) for both articular- and bursal-sided tears, respectively. Intra-observer agreement for the interpretation of articular- and bursal-sided tears was excellent and good, respectively, whereas intra-observer agreement for both articular- and bursal-sided tears was moderate. MR arthrography is a useful diagnostic tool for partial-thickness rotator cuff tears, but has limitations in that it has low sensitivity in bursal- and

  14. Comparisons of the Various Partial-Thickness Rotator Cuff Tears on MR Arthrography and Arthroscopic Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kyung Ah; Kim, Min Sung; Kim, Young Joo [Catholic University of Korea Uijeongbu St.Mary' s Hospital, Uijeongbu (Korea, Republic of)

    2010-10-15

    To assess the diagnostic performance of MR arthrography in the diagnosis of the various types of partial-thickness rotator cuff tears by comparing the MR imaging findings with the arthroscopic findings. The series of MR arthrography studies included 202 patients consisting of 100 patients with partial-thickness rotator cuff tears proved by arthroscopy and a control group of 102 patients with arthroscopically intact rotator cuffs, which were reviewed in random order. At arthroscopy, 54 articularsided, 26 bursal-sided, 20 both articular- and bursal-sided partial-thickness tears were diagnosed. The MR arthrographies were analyzed by two radiologists for articular-sided tears, bursal-sided tears, and both articular- and bursal-sided tears of the rotator cuff. The sensitivity and specificity of each type of partial-thickness tears were determined. Kappa statistics was calculated to determine the interand intra-observer agreement of the diagnosis of partial-thickness rotator cuff tears. The sensitivity and specificity of the various types of rotator cuff tears were 85% and 90%, respectively for articular-sided tears, 62% and 95% for bursal- sided tears, as well as 45% and 99% for both articular- and bursal-sided tears. False-negative assessments were primarily observed in the diagnosis of bursal-sided tears. Conversely, both articular- and bursal-sided tears were overestimated as full-thickness tears. Inter-observer agreement was excellent for the diagnosis of articular-sided tears (k = 0.70), moderate (k = 0.59) for bursal-sided tears, and fair (k = 0.34) for both articular- and bursal-sided tears, respectively. Intra-observer agreement for the interpretation of articular- and bursal-sided tears was excellent and good, respectively, whereas intra-observer agreement for both articular- and bursal-sided tears was moderate. MR arthrography is a useful diagnostic tool for partial-thickness rotator cuff tears, but has limitations in that it has low sensitivity in bursal- and

  15. Anterior versus posterior, and rim-rent rotator cuff tears: prevalence and MR sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Tuite, M J; Turnbull, J R; Orwin, J F [Wisconsin Univ., Madison, WI (United States). Dept. of Radiology

    1998-05-01

    Purpose. To determine the relative distribution of the locations of rotator cuff tears, and the sensitivity of anterior versus posterior tears on MR images. Patients and methods. We identified 110 consecutive patients who had a shoulder MR and either a partial-thickness or a small full-thickness rotator cuff tear diagnosed at arthroscopy. From the arthroscopy videotapes, we classified the tears as centered in the anterior or posterior half of the cuff, and as either in the critical zone or adjacent to the bony insertion. The original MR interpretation was compared with the arthroscopic findings. MR sensitivity and patient age were compared between patients with tears in the anterior and posterior halves of the cuff. In addition, in patients with partial tears less than 2 cm in diameter, an age comparison between those with tears in the critical zone and those with articular surface tears adjacent to the bony insertion (rim-rent tear) was performed. Results. The tear was centered in the anterior half of the rotator cuff in 79% of the patients younger than 36 years old, and in 89% of the patients 36 years old and over. The average age of the patients with tears in the anterior half (44 years) was not significantly different from the average age of those with posterior tears (40 years)(P=0.23). The sensitivity of MR for anterior tears was 0.69, and for posterior tears it was 0.56 (P=0.17). The average age of the 9 patients with rim-rent tears was 31 years, while that of the 28 patients with similarly-sized partial tears not involving the insertion was 40 years old (P=0.048). Five of the nine rim-rent tears (0.56) were interpreted correctly on the original MR report; two of the other tears were misinterpreted as intratendinous fluid but were diagnosable in retrospect. Conclusion. Even in patients less than 36 years old, most partial and small full-thickness rotator cuff tears are centered in the anterior half of the supraspinatus. Although our figure for MR sensitivity

  16. Pele's tears and spheres: Examples from Kilauea Iki

    Science.gov (United States)

    Porritt, L. A.; Russell, J. K.; Quane, S. L.

    2012-06-01

    Pele's tears are a well known curiosity commonly associated with low viscosity basaltic explosive eruptions. However, detailed studies of these pyroclasts are rare and, thus, there is no full explanation for their formation. These intriguing pyroclasts have smooth glassy surfaces, vesiculated interiors (∼30%), and fluidal morphologies trending towards teardrops and then spheres as they decrease in size to Pele's tears from the 1959 fire-fountaining eruption of Kilauea Iki has led to a reassessment of the mechanisms of magma disruption and fragmentation, timescales of relaxation, and cooling rates that are responsible for their formation. We conclude that the particle size distributions and vesicularities of Pele's tears are representative of the magma properties at the moment of explosive disruption. However, the morphology of these unique pyroclasts results from reshaping through viscous relaxation, driven by surface tension forces, on a time scale fast enough to compete with cooling times.

  17. Risk Factors, Pathobiomechanics and Physical Examination of Rotator Cuff Tears

    Science.gov (United States)

    Moulton, Samuel G.; Greenspoon, Joshua A.; Millett, Peter J.; Petri, Maximilian

    2016-01-01

    Background: It is important to appreciate the risk factors for the development of rotator cuff tears and specific physical examination maneuvers. Methods: A selective literature search was performed. Results: Numerous well-designed studies have demonstrated that common risk factors include age, occupation, and anatomic considerations such as the critical shoulder angle. Recently, research has also reported a genetic component as well. The rotator cuff axially compresses the humeral head in the glenohumeral joint and provides rotational motion and abduction. Forces are grouped into coronal and axial force couples. Rotator cuff tears are thought to occur when the force couples become imbalanced. Conclusion: Physical examination is essential to determining whether a patient has an anterosuperior or posterosuperior tear. Diagnostic accuracy increases when combining a series of examination maneuvers. PMID:27708731

  18. Cytokine and chemokine levels in tears from healthy subjects.

    Science.gov (United States)

    Carreño, Ester; Enríquez-de-Salamanca, Amalia; Tesón, Marisa; García-Vázquez, Carmen; Stern, Michael E; Whitcup, Scott M; Calonge, Margarita

    2010-11-01

    There is growing evidence for the existence of an 'immune tone' in normal tears. The aim of this study was to determine the levels of a large panel of cytokines and chemokines in tears obtained from healthy subjects. These levels can then serve as baseline values for comparison with patients suffering from ocular surface diseases. Nine healthy subjects participated in this study, and normal ocular surface health was documented by the results of a dry eye questionnaire, Schirmer strip wetting, and vital staining of the cornea. Four microliters of tears were collected from each eye and analysed separately with multiplex bead-based assays for the concentration of 30 cytokines and chemokines. Twenty-five cytokines/chemokines were detected. CCL11/Eotaxin1, GM-CSF, G-CSF, IFN-γ, IL-2, IL-3, IL-4, IL-5, IL-10, IL-13, IL-12p70, IL-15, CX3CL1/Fractalkine, TNF-α, epidermal growth factor, and CCL4/MIP-1β were present at 5-100 pg/ml. IL-1β, IL-6, IL-7A, CXCL8/IL-8, and CCL2/MCP-1 were present at 100-400 pg/ml. IL-1Ra, CXCL10/IP-10 and vascular endothelial growth factor were present at more than 1000 pg/ml. Multiplex bead-based assays are convenient for cytokine/chemokine detection in tears. Fracktalkine has been detected in human healthy tears for the first time. The knowledge of cytokine/chemokine concentrations in tears from normal subjects is an important reference for further comparison with patients suffering from ocular surface diseases. Variability in their levels can reflect a phenomenon of potential importance for the understanding of the ocular surface cytokine pattern. © 2010 The Authors. Journal compilation © 2010 Acta Ophthalmol.

  19. Rotator cuff tears noncontrast MRI compared to MR arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Hyun; Yoon, Young Cheol [Sungkyunkwan University, School of Medicine, Department of Radiology, Samsung Medical Center, Gangnam-gu, Seoul (Korea, Republic of); Jung, Jee Young [Chungang University School of Medicine, Department of Radiology, Chungang University Hospital, Seoul (Korea, Republic of); Yoo, Jae Chul [Sungkyunkwan University, School of Medicine, Department of Orthopedic Surgery, Samsung Medical Center, Seoul (Korea, Republic of)

    2015-12-15

    To compare the accuracy of indirect magnetic resonance arthrography and noncontrast magnetic resonance imaging for diagnosing rotator cuff tears. In total, 333 patients who underwent noncontrast magnetic resonance imaging or indirect magnetic resonance arthrography were included retrospectively. Two musculoskeletal radiologists evaluated the images for the presence of supraspinatus-infraspinatus and subscapularis tendon tears. The overall diagnostic performance was calculated using the arthroscopic findings as the reference standard. Statistical differences between the diagnostic performances of the two methods were analyzed. Ninety-six and 237 patients who underwent noncontrast magnetic resonance imaging and indirect magnetic resonance arthrography were assigned into groups A and B, respectively. Sensitivity for diagnosing articular-surface partial-thickness supraspinatus-infraspinatus tendon tear was slightly higher in group B than in group A. Statistical significance was confirmed by multivariate analysis using the generalized estimating equation (p = 0.046). The specificity for diagnosing subscapularis tendon tear (85 % vs. 68 %, p = 0.012) and grading accuracy (57 % vs. 40 %, p = 0.005) was higher in group B than in group A; the differences were statistically significant for one out of two readers. Univariate analysis using the generalized estimating equation showed that the accuracy for diagnosing subscapularis tendon tear in group B was higher than in group A (p = 0.042). There were no statistically significant differences between the diagnostic performances of both methods for any other parameters. Indirect magnetic resonance arthrography may facilitate more accurate diagnosis and grading of subscapularis tendon tears compared with noncontrast magnetic resonance imaging. (orig.)

  20. Is nonoperative management of partial distal biceps tears really successful?

    Science.gov (United States)

    Bauer, Tyler M; Wong, Justin C; Lazarus, Mark D

    2018-04-01

    The current treatment of partial distal biceps tears is a period of nonoperative management, followed by surgery, if symptoms persist. Little is known about the success rate and outcomes of nonoperative management of this illness. We identified 132 patients with partial distal biceps tears through an International Classification of Diseases, Ninth Revision code query of our institution's database. Patient records were reviewed to abstract demographic information and confirm partial tears of the distal biceps tendon based on clinical examination findings and confirmatory magnetic resonance imaging (MRI). Seventy-four patients completed an outcome survey. In our study, 55.7% of the contacted patients who tried a nonoperative course (34 of 61 patients) ultimately underwent surgery, and 13 patients underwent immediate surgery. High-need patients, as defined by occupation, were more likely to report that they recovered ideally if they underwent surgery, as compared with those who did not undergo surgery (odds ratio, 11.58; P = .0138). For low-need patients, the same analysis was not statistically significant (P = .139). There was no difference in satisfaction scores between patients who tried a nonoperative course before surgery and those who underwent immediate surgery (P = .854). An MRI-diagnosed tear of greater than 50% was a predictor of needing surgery (odds ratio, 3.0; P = .006). This study has identified clinically relevant information for the treatment of partial distal biceps tears, including the following: the failure rate of nonoperative treatment, the establishment of MRI percent tear as a predictor of failing nonoperative management, the benefit of surgery for the high-need occupational group, and the finding that nonoperative management does not negatively affect outcome if subsequent surgery is necessary. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  1. Tear film proteome in age-related macular degeneration.

    Science.gov (United States)

    Winiarczyk, Mateusz; Kaarniranta, Kai; Winiarczyk, Stanisław; Adaszek, Łukasz; Winiarczyk, Dagmara; Mackiewicz, Jerzy

    2018-06-01

    Age-related macular degeneration (AMD) is the main reason for blindness in elderly people in the developed countries. Current screening protocols have limitations in detecting the early signs of retinal degeneration. Therefore, it would be desirable to find novel biomarkers for early detection of AMD. Development of novel biomarkers would help in the prevention, diagnostics, and treatment of AMD. Proteomic analysis of tear film has shown promise in this research area. If an optimal set of biomarkers could be obtained from accessible body fluids, it would represent a reliable way to monitor disease progression and response to novel therapies. Tear films were collected on Schirmer strips from a total of 22 patients (8 with wet AMD, 6 with dry AMD, and 8 control individuals). 2D electrophoresis was used to separate tear film proteins prior to their identification with matrix-assisted laser desorption/ionization time of flight spectrometer (MALDI-TOF/TOF) and matching with functional databases. A total of 342 proteins were identified. Most of them were previously described in various proteomic studies concerning AMD. Shootin-1, histatin-3, fidgetin-like protein 1, SRC kinase signaling inhibitor, Graves disease carrier protein, actin cytoplasmic 1, prolactin-inducible protein 1, and protein S100-A7A were upregulated in the tear film samples isolated from AMD patients and were not previously linked with this disease in any proteomic analysis. The upregulated proteins supplement our current knowledge of AMD pathogenesis, providing evidence that certain specific proteins are expressed into the tear film in AMD. As far we are aware, this is the first study to have undertaken a comprehensive in-depth analysis of the human tear film proteome in AMD patients.

  2. Rotator cuff tears noncontrast MRI compared to MR arthrography

    International Nuclear Information System (INIS)

    Lee, Ji Hyun; Yoon, Young Cheol; Jung, Jee Young; Yoo, Jae Chul

    2015-01-01

    To compare the accuracy of indirect magnetic resonance arthrography and noncontrast magnetic resonance imaging for diagnosing rotator cuff tears. In total, 333 patients who underwent noncontrast magnetic resonance imaging or indirect magnetic resonance arthrography were included retrospectively. Two musculoskeletal radiologists evaluated the images for the presence of supraspinatus-infraspinatus and subscapularis tendon tears. The overall diagnostic performance was calculated using the arthroscopic findings as the reference standard. Statistical differences between the diagnostic performances of the two methods were analyzed. Ninety-six and 237 patients who underwent noncontrast magnetic resonance imaging and indirect magnetic resonance arthrography were assigned into groups A and B, respectively. Sensitivity for diagnosing articular-surface partial-thickness supraspinatus-infraspinatus tendon tear was slightly higher in group B than in group A. Statistical significance was confirmed by multivariate analysis using the generalized estimating equation (p = 0.046). The specificity for diagnosing subscapularis tendon tear (85 % vs. 68 %, p = 0.012) and grading accuracy (57 % vs. 40 %, p = 0.005) was higher in group B than in group A; the differences were statistically significant for one out of two readers. Univariate analysis using the generalized estimating equation showed that the accuracy for diagnosing subscapularis tendon tear in group B was higher than in group A (p = 0.042). There were no statistically significant differences between the diagnostic performances of both methods for any other parameters. Indirect magnetic resonance arthrography may facilitate more accurate diagnosis and grading of subscapularis tendon tears compared with noncontrast magnetic resonance imaging. (orig.)

  3. Muscle architectural changes after massive human rotator cuff tear.

    Science.gov (United States)

    Gibbons, Michael C; Sato, Eugene J; Bachasson, Damien; Cheng, Timothy; Azimi, Hassan; Schenk, Simon; Engler, Adam J; Singh, Anshuman; Ward, Samuel R

    2016-12-01

    Rotator cuff (RC) tendon tears lead to negative structural and functional changes in the associated musculature. The structural features of muscle that predict function are termed "muscle architecture." Although the architectural features of "normal" rotator cuff muscles are known, they are poorly understood in the context of cuff pathology. The purpose of this study was to investigate the effects of tear and repair on RC muscle architecture. To this end thirty cadaveric shoulders were grouped into one of four categories based on tear magnitude: Intact, Full-thickness tear (FTT), Massive tear (MT), or Intervention if sutures or hardware were present, and key parameters of muscle architecture were measured. We found that muscle mass and fiber length decreased proportionally with tear size, with significant differences between all groups. Conversely, sarcomere number was reduced in both FTT and MT with no significant difference between these two groups, in large part because sarcomere length was significantly reduced in MT but not FTT. The loss of muscle mass in FTT is due, in part, to subtraction of serial sarcomeres, which may help preserve sarcomere length. This indicates that function in FTT may be impaired, but there is some remaining mechanical loading to maintain "normal" sarcomere length-tension relationships. However, the changes resulting from MT suggest more severe limitations in force-generating capacity because sarcomere length-tension relationships are no longer normal. The architectural deficits observed in MT muscles may indicate deeper deficiencies in muscle adaptability to length change, which could negatively impact RC function despite successful anatomical repair. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2089-2095, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  4. Supraspinatus tendon tears: comparison of US and MR arthrography with surgical correlation

    International Nuclear Information System (INIS)

    Ferrari, Francesco S.; Governi, Simone; Burresi, Francesca; Vigni, Francesco; Stefani, Paolo

    2002-01-01

    The aim of this study was to compare the diagnostic reliability of US with MR arthrography in diagnosing supraspinatus tendon tears. Surgical findings were used as the gold standard in detecting tears. A total of 44 patients were assessed with transverse and longitudinal US scans with respect to the long axis of the rotator cuff tendons and then examined with MR arthrography. This technique involved free-hand injection of contrast medium into the shoulder joint. At surgery 20 incomplete and 24 complete tears were observed. Ultrasound offered good results for the large tears, but its sensitivity decreased proportionally with the size of the tears. Magnetic resonance arthrography correctly diagnosed 43 tears, whereas only one false-negative diagnosis of tendinosis was made for a partial tear on the bursal side. Since it improves the diagnosis of small tears, MR arthrography must be performed on all patients for whom surgical repair is necessary in order to restore normal functions. (orig.)

  5. Supraspinatus tendon tears: comparison of US and MR arthrography with surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, Francesco S.; Governi, Simone; Burresi, Francesca; Vigni, Francesco; Stefani, Paolo [Department of Radiologic and Orthopaedic-Rehabilitative Sciences, University Hospital Siena (Italy)

    2002-05-01

    The aim of this study was to compare the diagnostic reliability of US with MR arthrography in diagnosing supraspinatus tendon tears. Surgical findings were used as the gold standard in detecting tears. A total of 44 patients were assessed with transverse and longitudinal US scans with respect to the long axis of the rotator cuff tendons and then examined with MR arthrography. This technique involved free-hand injection of contrast medium into the shoulder joint. At surgery 20 incomplete and 24 complete tears were observed. Ultrasound offered good results for the large tears, but its sensitivity decreased proportionally with the size of the tears. Magnetic resonance arthrography correctly diagnosed 43 tears, whereas only one false-negative diagnosis of tendinosis was made for a partial tear on the bursal side. Since it improves the diagnosis of small tears, MR arthrography must be performed on all patients for whom surgical repair is necessary in order to restore normal functions. (orig.)

  6. 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

  7. Tear osmolarity and dry eye symptoms in diabetics

    Directory of Open Access Journals (Sweden)

    Fuerst N

    2014-03-01

    Full Text Available Nicole Fuerst,1 Nicole Langelier,1 Mina Massaro-Giordano,1 Maxwell Pistilli,1 Kalliopi Stasi,1 Carrie Burns,2 Serena Cardillo,2 Vatinee Y Bunya1 1Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA; 2Division of Endocrinology, Diabetes, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA Purpose: To assess the relationship between tear osmolarity and dry eye symptoms in patients with diabetes. Patients and methods: Fifty patients with diabetes were enrolled. Demographic information and past medical history were recorded. Symptoms were assessed using the ocular surface disease index (OSDI. Tear osmolarity of each eye was measured with the TearLab® Osmolarity System. Results: The majority of the subjects were female (76%, African American (56%, and/or had a diagnosis of type 2 diabetes (82%. The mean ± standard deviation (SD for age was 54.6±13.4, and maximum tear osmolarity was 304.6±12.7 mOsm/L. Men had higher osmolarity than women (mean ± standard error (SE 311.8±4.0 mOsm/L versus 302.3±1.9 mOsm/L, P=0.02. Age, race, use of artificial tears, years of diabetes, and hemoglobin A1c did not have a statistically significant association with tear osmolarity. Longer duration of diabetes was associated with lower (less severe OSDI scores (r=-0.35, P=0.01. Higher tear osmolarity was associated with lower (less severe OSDI scores (r=-0.29, P=0.04. Conclusion: Approximately half of the diabetic subjects in our study had elevated tear osmolarity, and half of our population also reported symptoms consistent with dry eye disease. However, the two were slightly inversely related in that those with higher osmolarity reported fewer symptoms. Subjects with a longer duration of diabetes also reported fewer dry eye symptoms. Therefore, health care providers should be aware that patients who are most likely to have ocular surface disease, including those with

  8. Daytime Variations of Tear Osmolarity Measurement in Dry Eye Patients

    Directory of Open Access Journals (Sweden)

    Ulviye Yiğit

    2013-12-01

    Full Text Available Purpose: We have targeted primarily to show the variations of tear osmolarity during the daytime period in subjects with dry eyes and non-dry eyes and, secondarily, to evaluate the relationship of these variations with Schirmer’s test and break-up time (BUT. Material and Method: Twenty newly diagnosed dry eye patients and 20 healthy voluntary subjects with similar age and gender were included in this prospective study. In addition to the full ophthalmic examination, Schirmer’s test and BUT test were applied to all participants. Tear osmolarity measurements were done after pre-examination but in different day. The measurements were registered with TearLab Osmolarity System (TearLab Corporation, San Diego, CA, USA every 3 hours within 8:00 AM and 5:00 PM. The results were evaluated statistically. Results: No statistically significant difference was found between the mean age and gender of dry eye syndrome (DES and control groups (p>0.05. The mean measurements of Schirmer’s test and BUT in the DES group were statistically significantly lower than those in the control group (p=0.0001. The mean measurements of tear osmolarity at 8:00 AM, 11:00 AM, 2:00 PM, and 5:00 PM in the DES group were statistically significantly higher than those in the control group (p=0.001, p=0.0001. No statistically significant difference in tear osmolarity at 8:00 AM, 11: 00 AM, 2:00 PM, and 5:00 PM was found between the groups, and within DES and control groups (p>0.05. Discussion: We did not determine significant change in daytime variations of the tear osmolarity in dry eye patients and healthy subjects. As a secondary result, we can conclude that there is no difference among tear osmolarity, Shirmer’s and BUT tests in the diagnosis of DES. (Turk J Ophthalmol 2013; 43: 437-41

  9. Hyper-resistivity produced by tearing mode turbulence

    International Nuclear Information System (INIS)

    Strauss, H.R.

    1986-01-01

    Tearing mode turbulence produces a hyper-resistivity or effective anomalous electron viscosity. The hyper-resistivity is calculated for the mean magnetic field quasilinearly, and for long-wavelength modes using the direct interaction approximation. The hyper-resistivity accounts for current relaxation in reversed-field pinch experiments, and gives a magnetic fluctuation sealing of S -1 /sup // 3 . It causes enhanced tearing mode growth rates in the turbulent phase of tokamak disruptions. In astrophysics, it limits magnetic energy growth due to the dynamo effect, and may explain rapid reconnection phenomena such as solar flares

  10. Mode coupling trigger of neoclassical magnetohydrodynamic tearing modes in tokamaks

    International Nuclear Information System (INIS)

    Gianakon, T.A.; Hegna, C.C.; Callen, J.D.

    1997-05-01

    Numerical studies of the nonlinear evolution of coupled magnetohydrodynamic - type tearing modes in three-dimensional toroidal geometry with neoclassical effects are presented. The inclusion of neoclassical physics introduces an additional free-energy source for the nonlinear formation of magnetic islands through the effects of a bootstrap current in Ohm's law. The neoclassical tearing mode is demonstrated to be destabilized in plasmas which are otherwise Δ' stable, albeit once a threshold island width is exceeded. A possible mechanism for exceeding or eliminating this threshold condition is demonstrated based on mode coupling due to toroidicity with a pre-existing instability at the q = 1 surface

  11. Winging of scapula due to serratus anterior tear

    Directory of Open Access Journals (Sweden)

    Varun Singh Kumar

    2014-10-01

    Full Text Available 【Abstract】Winging of scapula occurs most commonly due to injury to long thoracic nerve supplying serratus anterior muscle. Traumatic injury to serratus anterior muscle itself is very rare. We reported a case of traumatic winging of scapula due to tear of serratus anterior muscle in a 19-year-old male. Winging was present in neutral position and in extension of right shoulder joint but not on "push on wall" test. Patient was managed conservatively and achieved satisfactory result. Key words: Serratus anterior tear; Scapula; Wounds and injuries

  12. Stability of short wavelength tearing and twisting modes

    International Nuclear Information System (INIS)

    Waelbroeck, F.L.

    1998-01-01

    The stability and mutual interaction of tearing and twisting modes in a torus is governed by matrices that generalize the well-known Δ' stability index. The diagonal elements of these matrices determine the intrinsic stability of modes that reconnect the magnetic field at a single resonant surface. The off-diagonal elements indicate the strength of the coupling between the different modes. The author shows how the elements of these matrices can be evaluated, in the limit of short wavelength, from the free energy driving radially extended ballooning modes. The author applies the results by calculating the tearing and twisting Δ' for a model high-beta equilibrium with circular flux surfaces

  13. Electron diamagnetism and toroidal coupling of tearing modes

    International Nuclear Information System (INIS)

    Cowley, S.C.; Hastie, R.J.

    1987-10-01

    Using a simple model for the layer of the tearing mode, we demonstrate that toroidally coupled tearing modes with two rational surfaces are most unstable when the ω*'s of the electrons at the rational surfaces are equal. The onset of instability may then occur because of the tuning of ω* rather than the passage of Δ'-like quantities through zero. This mechanism for the onset of instability is sharp since the resonance is narrow. The effect of toroidal rotation is also discussed. 7 refs., 2 figs

  14. Skin tears: care and management of the older adult at home.

    Science.gov (United States)

    Holmes, Regina F; Davidson, Martha W; Thompson, Bonnie J; Kelechi, Teresa J

    2013-02-01

    Skin tears experienced by older adults require special skills to promote healing. Home healthcare providers are in key positions to manage skin tears and prevent further skin trauma. Several guidelines, risk assessments, classifications, and products exist to manage high-risk patients. Frequent evaluation of the effectiveness of the treatment and prevention strategies in an overall skin care protocol for home care patients is critical to reduce skin tear incidence and promote prompt healing when skin tears are present.

  15. Increasing age and tear size reduce rotator cuff repair healing rate at 1 year.

    Science.gov (United States)

    Rashid, Mustafa S; Cooper, Cushla; Cook, Jonathan; Cooper, David; Dakin, Stephanie G; Snelling, Sarah; Carr, Andrew J

    2017-12-01

    Background and purpose - There is a need to understand the reasons why a high proportion of rotator cuff repairs fail to heal. Using data from a large randomized clinical trial, we evaluated age and tear size as risk factors for failure of rotator cuff repair. Patients and methods - Between 2007 and 2014, 65 surgeons from 47 hospitals in the National Health Service (NHS) recruited 447 patients with atraumatic rotator cuff tendon tears to the United Kingdom Rotator Cuff Trial (UKUFF) and 256 underwent rotator cuff repair. Cuff integrity was assessed by imaging in 217 patients, at 12 months post-operation. Logistic regression analysis was used to determine the influence of age and intra-operative tear size on healing. Hand dominance, sex, and previous steroid injections were controlled for. Results - The overall healing rate was 122/217 (56%) at 12 months. Healing rate decreased with increasing tear size (small tears 66%, medium tears 68%, large tears 47%, and massive tears 27% healed). The mean age of patients with a healed repair was 61 years compared with 64 years for those with a non-healed repair. Mean age increased with larger tear sizes (small tears 59 years, medium tears 62 years, large tears 64 years, and massive tears 66 years). Increasing age was an independent factor that negatively influenced healing, even after controlling for tear size. Only massive tears were an independent predictor of non-healing, after controlling for age. Interpretation - Although increasing age and larger tear size are both risks for failure of rotator cuff repair healing, age is the dominant risk factor.

  16. 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.

  17. 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.

  18. Instability threshold of neoclassical tearing mode, double tearing mode and off-axis sawteeth crash in tokamaks

    International Nuclear Information System (INIS)

    Li, D.

    2001-01-01

    The neoclassical and double tearing modes have been analyzed with related new phenomena in the reversed magnetic shear tokamak plasmas. The instability threshold, and the linear and nonlinear evolution are derived for the neoclassical tearing modes. It is found that the perturbed bootstrap current in the resistive layer has a stabilizing effect while the equilibrium bootstrap current in the outer region can destabilize the modes. The dispersion relation is derived for the double tearing mode. It is found that the onset of ''annular crash'' is due to the fast reconnection of the hot and cold islands, triggered by the interaction of both branches. The onset of ''core crash'' is mainly due to the coalescence between the hot islands, triggered by the explosive growth of the inner branch. (author)

  19. Instability threshold of neoclassical tearing mode, double tearing mode and off-axis sawteeth crash in tokamaks

    International Nuclear Information System (INIS)

    Li Ding

    1999-01-01

    The neoclassical and double tearing modes have been analyzed with related new phenomena in the reversed magnetic shear tokamak plasmas. The instability threshold, and the linear and nonlinear evolution are derived for the neoclassical tearing modes. It is found that the perturbed bootstrap current in the resistive layer has a stabilizing effect while the equilibrium bootstrap current in the outer region can destabilize the modes. The dispersion relation is derived for the double tearing mode. It is found that the onset of 'annular crash' is due to the fast reconnection of the hot and cold islands, triggered by the interaction of both branches. The onset of 'core crash' is mainly due to the coalescence between the hot islands, triggered by the explosive growth of the inner branch. (author)

  20. 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.

  1. Spectral-domain optical coherence tomography study on dynamic changes of human tears after instillation of artificial tears.

    Science.gov (United States)

    Napoli, Pietro Emanuele; Satta, Giovanni Maria; Coronella, Franco; Fossarello, Maurizio

    2014-07-01

    To analyze in vivo the dynamic changes induced by different artificial tears (ATs) in the precorneal tear film (PCTF) and lower tear meniscus (LTM) by using spectral-domain (SD) anterior segment optical coherence tomography (OCT). We prospectively examined 42 normal human eyes by using SD-OCT imaging. On the day before OCT imaging, all enrolled subjects were evaluated for abnormalities of ocular surface. All tear film images were obtained before and after instillation of three different types of ATs (mucomimetic, lipid-based, and saline) in five serial scans: immediately (within 30 seconds), at the first, fifth, 10th, and 20th minute. Subjects received a drop of 35 μL in one randomly selected eye. All examinations were conducted in the same conditions of temperature, brightness, humidity, and time of day. Changes in the morphological pattern of both LTM and PCTF were associated with the type of artificial tear instilled on the ocular surface. Similarly, the radius of curvature (rc), the height (h), and the depth (d) showed dynamic variations depending on treatment. Although by the 20th minute, both h and d returned to baseline values in all groups, a significant difference in rc (compared with baseline) was detected for mucomimetic ATs (P = 0.04) and lipid ATs (P = 0.02). Spectral-domain OCT imaging has preliminarily proved to be a noninvasive tool to evaluate, in real time, the different changes induced by ATs instillation. An important stride in understanding the clinical response to various tear substitutes can be achieved by this objective and quantitative approach. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  2. Evaluation of the tear film stability after laser in situ keratomileusis using the tear film stability analysis system.

    Science.gov (United States)

    Goto, Tomoko; Zheng, Xiaodong; Klyce, Stephen D; Kataoka, Hisashi; Uno, Toshihiko; Yamaguchi, Masahiko; Karon, Mike; Hirano, Sumie; Okamoto, Shigeki; Ohashi, Yuichi

    2004-01-01

    To evaluate the tear film stability of patients before and after laser in situ keratomileusis (LASIK) using the tear film stability analysis system (TSAS). Prospective observational case series. New videokeratography software for a topographic modeling system (TMS-2N) was developed that can automatically capture consecutive corneal surface images every second for 10 seconds. Thirty-four subjects (64 eyes) who underwent myopia LASIK were enrolled in this study. All subjects were examined with the new system before LASIK and at 1 week, 1 month, 3 months, and 6 months after the surgery. Corneal topographs were analyzed for tear breakup time (TMS breakup time) and breakup area (TMS breakup area). Based on pre-LASIK TSAS analysis, subjects were separated into normal and abnormal TSAS value groups. The criteria for the normal group were either TMS breakup time more than 5 seconds or TMS breakup area less than 0.2. The percentage of the occurrence of superficial punctuate keratitis was compared between the two groups with regard to subject's dry eye signs and symptoms. Tear film stability decreased significantly during the early period after LASIK, as indexed by decreased TMS breakup time and increased TMS breakup area. Tear film instability resolved at 6 months after surgery. Before LASIK, 22 subjects (43 eyes) had normal TSAS evaluation and 12 subjects (21 eyes) were abnormal. After LASIK, among normal TSAS value eyes, 8 of 43 (18.6%) eyes developed superficial punctuate keratitis. In sharp contrast, 14 of 21 (66.7%) eyes in the abnormal group displayed superficial punctuate keratitis, correlating well with the patients' dry eye symptoms. The difference in the presence of superficial punctuate keratitis after LASIK between normal and abnormal TSAS value groups was statistically significant (P <.001). Subjects with abnormal TSAS evaluation also displayed resistance to dry eye treatment and had extended period of recovery. Tear film stability analysis can be a useful

  3. Detection of endogenous cortisol in equine tears and blood at rest and after simulated stress.

    Science.gov (United States)

    Monk, Caroline S; Hart, Kelsey A; Berghaus, Roy D; Norton, Natalie A; Moore, Phillip A; Myrna, Kathern E

    2014-07-01

    To determine whether cortisol is present in equine tears at rest and during simulated stress and compare tear cortisol to serum free and total cortisol. Fourteen healthy adult horses were included. Paired tear total cortisol and serum total and free cortisol concentrations were measured with ELISA, chemiluminescent immunoassay, and ultrafiltration methodology, respectively, in 10 horses at rest once daily for five consecutive days. In an additional four horses, paired tear and serum samples were collected for cortisol measurement before and after adrenocorticotropic hormone (ACTH) stimulation (cosyntropin, 1 μg/kg IV). Cortisol was detectable in equine tears at rest. Following ACTH stimulation, tear cortisol increased significantly from baseline at 60-120 min (P ≤ 0.001). Serum total and free cortisol also increased significantly at 30-180 min after ACTH stimulation (P ≤ 0.001). Both serum and tear cortisol returned to baseline concentrations by 360 min. Changes in tear cortisol were similarly associated with changes in serum total and free cortisol, although high tear cortisol concentrations suggest a portion of tear cortisol may be protein-bound. Cortisol is present in equine tears and increases in concert with serum cortisol following ACTH stimulation. Further study is needed to determine whether endogenous cortisol in tears contributes to ocular pathology. © 2013 American College of Veterinary Ophthalmologists.

  4. Association of Strength Measurement with Rotator Cuff Tear in Patients with Shoulder Pain: The ROW Study

    Science.gov (United States)

    Miller, Jennifer Earle; Higgins, Laurence D.; Dong, Yan; Collins, Jamie E.; Bean, Jonathan F.; Seitz, Amee L.; Katz, Jeffrey N.; Jain, Nitin B.

    2016-01-01

    Objective This study examines the association between strength measurements and supraspinatus tear in patients with shoulder pain. This study characterized determinants of abduction strength among patients with tears. Design Two-hundred and eight patients with shoulder pain (69 with and 110 without tear) were recruited. Strength was tested using hand-held dynamometer. Supraspinatus tears were diagnosed by combination of clinical assessment and blinded MRI review. Associations of supraspinatus tear with patient characteristics and strength measurements (abduction, internal rotation and external rotation) were assessed using multivariable logistic regression models. Results Patients with supraspinatus tear had decreased abduction strength (p=0.02) and decreased external rotation strength (ptear laterality, and BMI, decreased abduction strength (OR= 1.18 per kg, 95% C.I.=1.06–1.32) and decreased external rotation strength (OR=1.29 per kg, 95% C.I.=1.14–1.48) were associated with supraspinatus tear. In patients with tear, age ≥60 years, female sex, and VAS pain score were significantly associated with decreased abduction strength but tear size, fatty infiltration, and atrophy were not. Conclusions Decreased abduction and external rotation strength were associated with supraspinatus tear in patients with shoulder pain. In this cohort, the abduction strength of patients with tears, was influenced by demographic factors but not tear characteristics. PMID:26098921

  5. The relation between invasive and non-invasive tear break-up time ...

    African Journals Online (AJOL)

    Tear stability normal to Nigerians with consideration of gender and age has not been reported. Tear stability in young adults was measured using invasive and non-invasive tear break-up time (TBUT and NIBUT). Forty –five subjects aged 20 to 30 years were selected from among the students of University of. Benin, Edo ...

  6. 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

  7. Conversion of the dominantly ideal perturbations into a tearing mode

    NARCIS (Netherlands)

    Igochine, V.; Gude, A.; Günter, S.; Lackner, K.; Yu, Q; Barrera Orte, L.; Bogomolov, A.; Classen, I.G.J.; McDermott, R.M.; Luhmann, N.C.

    2014-01-01

    Forced magnetic reconnection is a topic of common interest in astrophysics, space science, and magnetic fusion research. The tearing mode formation process after sawtooth crashes implies the existence of this type of magnetic reconnection and is investigated in great detail in the ASDEX Upgrade

  8. Equilibrium current-driven tearing mode in the hydrodynamic regime

    International Nuclear Information System (INIS)

    Cozzani, F.; Mahajan, S.

    1984-12-01

    The effect of the parallel equilibrium current on the linear stability of the drift-tearing mode in the collisional regime is investigated analytically. In the appropriate parameter regime, a new unstable mode, driven by equilibrium current, is found and its relevance to tokamak discharges is discussed

  9. Fighting, Anger, Frustration and Tears: Matthew's Story of Hegemonic Masculinity

    Science.gov (United States)

    Keddie, Amanda

    2006-01-01

    This paper draws on Matthew's story to illustrate the conflicting discourses of being a boy and being a student. Matthew is 12 years old and in Grade Six, his final year at Banrock Primary (a K-6 Australian State School). School is far from a happy place for Matthew--his tearful accounts of his combative relationships with his peers and his…

  10. Observations on Mode I ductile tearing in sheet metals

    DEFF Research Database (Denmark)

    El-Naaman, Salim Abdallah; Nielsen, Kim Lau

    2013-01-01

    Cracked ductile sheet metals, subject to Mode I tearing, have been observed to display a variety of fracture surface morphologies depending on the material properties, and a range of studies on the fracture surface appearance have been published in the literature. Whereas classical fractures...

  11. Assisted crack tip flipping under Mode I thin sheet tearing

    DEFF Research Database (Denmark)

    Felter, Christian Lotz; Nielsen, Kim Lau

    2017-01-01

    Crack tip flipping, where the fracture surface alternates from side to side in roughly 45° shear bands, seems to be an overlooked propagation mode in Mode I thin sheet tearing. In fact, observations of crack tip flipping is rarely found in the literature. Unlike the already established modes...

  12. Immunoglobulin Concentration in Tears of Contact Lens Wearers

    Directory of Open Access Journals (Sweden)

    Rajendra P Maurya

    2014-01-01

    Conclusion: The relation of immunoglobulin concentration with increasing duration of wear and material of contact lens shows that tear immunoglobulin rise accrues due to mechanical stimulation, hence contact lenses should not be used for a long period and lenses of hard nature should be discouraged. The maintenance, cleaning and deproteinization of the lenses are of high importance to avoid immunostimulation.

  13. Crack Tip Flipping Under Mode I/III Tearing

    DEFF Research Database (Denmark)

    Felter, Christian Lotz; Specht Jensen, Lasse; Nielsen, Kim Lau

    Crack tip flipping, where the fracture surface alternates from side to side in 45° shear bands, seems to be an overlooked propagation mode in Mode I sheet tearing often disregarded as  “transitional” or tied to randomness in the material. In fact, such observations rarely make it to the literature...

  14. Fracture Surface Morphology Under Ductile Tearing of Metal Plates

    DEFF Research Database (Denmark)

    Kacar, Muhammet F.; Tekoglu, Cihan; Nielsen, Kim Lau

    2017-01-01

    The present work takes as offset the hypothesis that microstructural parameters, related to particle size and distribution, govern the transition between crack surface morphologies observed in experiments. The key question is; why does tearing of a given metal plate leave a specific morphology...

  15. Tear Gas, Expanding Bullets and Plain-Clothed Personnel

    DEFF Research Database (Denmark)

    Wiesener, Cornelius Rust

    2017-01-01

    This article examines the interplay between human rights law and humanitarian law in relation to riot control agents (such as tear gas), expanding bullets and plain-clothed forces. While outlawed under humanitarian law, they are widely used by police in peace time and not subject to similar bans...

  16. A new algebraic growth of nonlinear tearing mode

    International Nuclear Information System (INIS)

    Li, D.

    1995-01-01

    It is found that the quasilinear modification of magnetic field produces a nonlinear Lorentz force opposing the linear driving force and slowing down the vortex flow. A new algebraic growth appears due to this damping mechanism to oppose the linear growth of the tearing mode. This effect was eliminated in Rutherford's model [Phys. Fluids 16, 1903 (1973)] under the flux average operation and the assumption ∂/∂t much-lt η/δ 2 (here η is the resistivity, δ is the resistive layer width). A unified analytical model is developed by using standard perturbation theory for the linear and nonlinear growth of the tearing mode. The inertia effect and quasilinear effects of both the current density and the magnetic field have been included. A nonlinear evolution equation is analytically derived for the tearing mode to describe the linear growth, Rutherford's behavior, and the new behavior. The classical linear result is exactly recovered as the quasilinear effects are negligible. It is shown that a more slowly algebraic growth like Ψ 1 ∝t can become dominant in the nonlinear phase instead of Rutherford behavior like Ψ 1 ∝t 2 , provided the tearing mode in the linear phase is strongly unstable. Here Ψ 1 is the magnetic flux perturbation. copyright 1995 American Institute of Physics

  17. Stop the Tears of Drug and Alcohol Abuse

    Science.gov (United States)

    Shimon, Jane; Gibson, Terry-Ann; Spear, Caile

    2009-01-01

    Objectives: By participating in this Stop the Tears teaching strategy, students will be able to: (1) analyze how alcohol and drug abuse could affect their lives as well as the lives of their friends and family and, (2) create a media message, such as a poster, pamphlet, poem, or song, in which alcohol and drug prevention is advocated specific to…

  18. Compensatory muscle activation in patients with glenohumeral cuff tears

    NARCIS (Netherlands)

    Steenbrink, Franciscus

    2010-01-01

    Patients suffering tendon tears in the glenohumeral cuff muscles show activation of muscles which pull the arm downwards during arm elevation tasks. This so-called co-activation deviates from healthy controls and is triggered by pain. Goal of this thesis was to demonstrate that deviating muscle

  19. THE EFFECT OF LOCAL ANESTHETICS ON TEAR PRODUCTION

    African Journals Online (AJOL)

    that local anesthetics measure only basic secretion thus reducing normal tear production/secretion, which is both reflex and basic.