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Sample records for carpometacarpal joint dislocation

  1. Divergent dislocation of the ring and little finger carpometacarpal joints--a rare injury pattern.

    LENUS (Irish Health Repository)

    Dillon, John

    2012-02-03

    Hand injuries due to longitudinal forces in the line of the metacarpals demonstrate unusual dislocation patterns. We describe a case of volar intra-articular fracture dislocation of the ring finger carpometacarpal joint in association with a pure dorsal dislocation of the little finger carpometacarpal joint. Open reduction supplemented with Kirschner wire fixation restored normal carpometacarpal joint anatomical relations and achieved an excellent clinical result.

  2. Volar dislocation of the index carpometacarpal joint in association with a Bennett's fracture of the thumb: a rare injury pattern.

    LENUS (Irish Health Repository)

    Dillon, J P

    2012-02-03

    We describe a case of volar dislocation of the index carpometacarpal (CMC) joint in association with a Bennett\\'s fracture of the thumb following a motorcycle accident. Volar dislocation of the index carpometacarpal joint is an exceedingly rare but easily missed injury, with only a few reported cases in the literature. This report highlights the importance of a true lateral radiograph and close scrutiny of the film to detect this injury. Closed reduction supplemented with Kirschner wire fixation restored normal anatomical relations and achieved an excellent clinical result.

  3. Multiple Volar Carpometacarpal Dislocations with Associated Carpal Tunnel Syndrome: A Case Report

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    C Fletcher

    2015-09-01

    Full Text Available We report a rare injury involving volar fracture dislocations of the second to fifth carpometacarpal dislocations. Carpometacarpal dislocations are usually dorsally displaced and most commonly only involve the fourth and fifth joints. An associated carpal tunnel syndrome adds another dimension to the complexity and rarity of the injury in this index case. A high index of clinical suspicion and subsequent emergent management is of utmost importance to treat this unusual combination of injuries in order to avoid significant morbidity.

  4. Failed total carpometacarpal joint prosthesis of the thumb

    DEFF Research Database (Denmark)

    Hansen, Torben Bæk; Homilius, Morten

    2010-01-01

    Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis. T...... in eight of 10 patients, but the mean Disabilities of the arm, shoulder, and hand (DASH) scores, self-reported pinch-grip-related function, and pain were comparable with our earlier published results with the Elektra carpometacarpal total joint prosthesis.......Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis....... The male:female ratio was 1:4 and the mean duration of observation 32 months (range 6-52). In three patients the revised implant was a MOJE uncemented carpometacarpal joint prosthesis and in seven patients an Elektra uncemented one. At follow-up grip strength was reduced to less than 90% of the other hand...

  5. Synovial Osteochondromatosis at the Carpometacarpal Joint of the Thumb

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    Satoru Yonekura

    2017-01-01

    Full Text Available Synovial osteochondromatosis (SOC is a benign tumor characterized by synovial connective tissue metaplasia. SOC commonly affects major joints including the knee followed by the hip, elbow, and wrist. SOC cases in the hand are not reported as often as SOC of major joints. Particularly SOC of the carpometacarpal joint of the thumb is rare. We report on a 57-year-old female with primary SOC of the carpometacarpal joint of her left thumb. Surgical excision was performed and the patient had no symptoms with full range of motion of her left thumb. At 3 years of follow-up, there was no recurrence.

  6. Autologous Fat Transfer for Thumb Carpometacarpal Joint Osteoarthritis: A Prospective Study.

    Science.gov (United States)

    Herold, Christian; Rennekampff, Hans-Oliver; Groddeck, Robert; Allert, Sixtus

    2017-08-01

    Most operations for carpometacarpal joint osteoarthritis of the thumb irreversibly alter or destroy the anatomy. There is a high demand for minimally invasive alternatives. The authors report the results of autologous fat transfer for treatment of thumb carpometacarpal joint osteoarthritis. In a prospective study, 50 patients with thumb carpometacarpal joint osteoarthritis were observed for 1 year after autologous fat transfer. Manual liposuction and centrifugation were performed. Pain rating according to visual analogue pain scale; objective force of pinch grip and fist closure; and Disabilities of the Arm, Shoulder, and Hand questionnaire scores before and after treatment were analyzed. The average pain in stage 2 patients preoperatively was 7.7 ± 1.3; it was 1.8 ± 1.9 after 6 months and 2.4 ± 3.1 after 12 months. Patients with stage 2 osteoarthritis demonstrated a superior benefit from this treatment compared with patients with either stage 3 or stage 4 thumb carpometacarpal joint osteoarthritis. There were similar improvements for the parameters strength and Disabilities of the Arm, Shoulder, and Hand questionnaire score. No serious adverse events were observed. Autologous fat transplantation is an appealing alternative, especially in early-stage basal joint osteoarthritis of the thumb. The low invasiveness of the procedure and early recovery of patients compared with classical procedures such as trapeziectomy, and the superior long-term results compared with classical injection therapy, make this approach feasible as a first-line therapy in early-stage basal joint osteoarthritis of the thumb. Therapeutic, IV.

  7. [Classification and Treatment of Sacroiliac Joint Dislocation].

    Science.gov (United States)

    Tan, Zhen; Huang, Zhong; Li, Liang; Meng, Wei-Kun; Liu, Lei; Zhang, Hui; Wang, Guang-Lin; Huang, Fu-Guo

    2017-09-01

    To develop a renewed classification and treatment regimen for sacroiliac joint dislocation. According to the direction of dislocation of sacroiliac joint,combined iliac,sacral fractures,and fracture morphology,sacroiliac joint dislocation was classified into 4 types. Type Ⅰ (sacroiliac anterior dislocation): main fracture fragments of posterior iliac wing dislocated in front of sacroiliac joint. Type Ⅱ (sacroiliac posterior dislocation): main fracture fragments of posterior iliac wing dislocated in posterior of sacroiliac joint. Type Ⅲ (Crescent fracturedislocation of the sacroiliac joint): upward dislocation of posterior iliac wing with oblique fracture through posterior iliac wing. Type ⅢA: a large crescent fragment and dislocation comprises no more than onethird of sacroiliac joint,which is typically inferior. Type ⅢB: intermediatesize crescent fragment and dislocation comprises between one and twothirds of joint. Type ⅢC: a small crescent fragment where dislocation comprises most,but not the entire joint. Different treatment regimens were selected for different types of fractures. Treatment for type Ⅰ sacroiliac joint dislocation: anterior iliac fossa approach pry stripping reset; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅱ sacroiliac joint dislocation: posterior sacroiliac joint posterior approach; sacroiliac joint fixed with sacroiliac screw under computer guidance. Treatment for type ⅢA and ⅢB sacroiliac joint dislocation: posterior sacroiliac joint approach; sacroiliac joint fixed with reconstruction plate. Treatment for type ⅢC sacroiliac joint dislocation: sacroiliac joint closed reduction; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅳ sacroiliac joint dislocation: posterior approach; sacroiliac joint fixed with spinal pelvic fixation. Results of 24 to 72 months patient follow-up (mean 34.5 months): 100% survival,100% wound healing,and 100

  8. Thumb carpometacarpal joint congruence during functional tasks and thumb range-of-motion activities

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    Halilaj, Eni; Moore, Douglas C; Patel, Tarpit K; Laidlaw, David H; Ladd, Amy L; Weiss, Arnold-Peter C; Crisco, Joseph J

    2017-01-01

    Joint incongruity is often cited as a possible etiological factor for the high incidence of thumb carpometacarpal (CMC) joint osteoarthritis (OA) in older women. There is evidence suggesting that biomechanics plays a role in CMC OA progression, but little is known about how CMC joint congruence, specifically, differs among different cohorts. The purpose of this in vivo study was to determine if CMC joint congruence differs with sex, age, and early stage OA for different thumb positions. Using CT data from 155 subjects and a congruence metric that is based on both articular morphology and joint posture, we did not find any differences in CMC joint congruence with sex or age group, but found that patients in the early stages of OA exhibit lower congruence than healthy subjects of the same age group. PMID:25570956

  9. Thumb carpometacarpal joint congruence during functional tasks and thumb range-of-motion activities.

    Science.gov (United States)

    Halilaj, Eni; Moore, Douglas C; Patel, Tarpit K; Laidlaw, David H; Ladd, Amy L; Weiss, Arnold-Peter C; Crisco, Joseph J

    2014-01-01

    Joint incongruity is often cited as a possible etiological factor for the high incidence of thumb carpometacarpal (CMC) joint osteoarthritis (OA) in older women. There is evidence suggesting that biomechanics plays a role in CMC OA progression, but little is known about how CMC joint congruence, specifically, differs among different cohorts. The purpose of this in vivo study was to determine if CMC joint congruence differs with sex, age, and early stage OA for different thumb positions. Using CT data from 155 subjects and a congruence metric that is based on both articular morphology and joint posture, we did not find any differences in CMC joint congruence with sex or age group, but found that patients in the early stages of OA exhibit lower congruence than healthy subjects of the same age group.

  10. [Staple fixation for the treatment of hamate metacarpal joint injury].

    Science.gov (United States)

    Tang, Yang-Hua; Zeng, Lin-Ru; Huang, Zhong-Ming; Yue, Zhen-Shuang; Xin, Da-Wei; Xu, Can-Da

    2014-03-01

    To investigate the effcacy of the staple fixation for the treatment of hamate metacarpal joint injury. From May 2009 to November 2012,16 patients with hamate metacarpal joint injury were treated with staple fixation including 10 males and 6 females with an average age of 33.6 years old ranging from 21 to 57 years. Among them, 11 cases were on the fourth or fifth metacarpal base dislocation without fractures, 5 cases were the fourth or fifth metacarpal base dislocation with avulsion fractures of the back of hamatum. Regular X-ray review was used to observe the fracture healing, joint replacement and position of staple fixation. The function of carpometacarpal joint and metacarpophalangeal joint were evaluated according to ASIA (TAM) system evaluation method. All incision were healed well with no infection. All patients were followed up from 16 to 24 months with an average of (10.0 +/- 2.7) months. No dislocation recurred, the position of internal fixator was good,no broken nail and screw withdrawal were occurred. Five patients with avulsion fracture of the back of hamatum achieved bone healing. The function of carpometacarpal joint and metacarpophalangeal was excellent in 10 cases,good in 5 cases, moderate in 1 case. The application of the staple for the treatment of hamatometacarpal joint injury has the advantages of simple operation, small trauma, reliable fixation, early postoperative function exercise and other advantages, which is the ideal operation mode for hamatometacarpal joint injury.

  11. Atraumatic Anterior Dislocation of the Hip Joint

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    Tadahiko Ohtsuru

    2015-01-01

    Full Text Available Dislocation of the hip joint in adults is usually caused by high-energy trauma such as road traffic accidents or falls from heights. Posterior dislocation is observed in most cases. However, atraumatic anterior dislocation of the hip joint is extremely rare. We present a case of atraumatic anterior dislocation of the hip joint that was induced by an activity of daily living. The possible causes of this dislocation were anterior capsule insufficiency due to developmental dysplasia of the hip, posterior pelvic tilt following thoracolumbar kyphosis due to vertebral fracture, and acetabular anterior coverage changes by postural factor. Acetabular anterior coverage changes in the sagittal plane were measured using a tomosynthesis imaging system. This system was useful for elucidation of the dislocation mechanism in the present case.

  12. Work-related bilateral osteoarthritis of the first carpometacarpal joints

    DEFF Research Database (Denmark)

    Jensen, Jens Christian; Sherson, David

    2007-01-01

    conditions, with photos and videos. The literature concerning first carpometacarpal OA was reviewed using PubMed. RESULTS: The observation of work conditions demonstrated unusual forceful and repetitive ulnar flexion of both first fingers. No competing causes of OA could be identified. CONCLUSION...

  13. Treatment of thumb carpometacarpal osteoarthritis; quo vadis?

    NARCIS (Netherlands)

    Spaans, Anne

    2016-01-01

    The unique prehensile ability of the human hand is largely due to the biomechanical function of its complex first carpometacarpal (CMC1) joint. This makes the thumb the most important digit of the hand. The unique demands placed on the thumb regarding mobility, stability and transmission of force

  14. Second carpal bone slab fracture and subluxation of the middle carpal joint in a horse subsequent to arthrodesis of the carpometacarpal joint.

    Science.gov (United States)

    MacKay, Angela V; Panizzi, Luca; Sparks, Holly D; Barber, Spencer M

    2015-02-01

    To report complications of arthrodesis of the carpometacarpal (CMC) joint using a drilling technique in an adult horse. Case report. Horse (n = 1). A 12-year-old Quarter Horse mare with CMC osteoarthritis (CMC-OA) had arthrodesis under general anesthesia in right lateral recumbency. Under fluoroscopic guidance, a 4.5 mm drill bit was inserted at 3 drilling sites 5-6 cm into the CMC joint and was fanned 30-45° in the plane of the joint and 5-10° in the long axis of the limb to destroy articular cartilage and expose the subchondral bone. The horse presented 2 weeks after surgery for severe lameness of the operated limb. A slab fracture of the 2nd carpal bone (C2) and subluxation of the middle carpal (MC) joint was diagnosed. The horse was humanely euthanatized due to poor prognosis. The fanning technique of arthrodesis of the CMC joint may lead to fracture of carpal bones, joint instability, and MC joint subluxation. A balance between articular surface destruction and maintenance of joint stability should be achieved when using this technique. © Copyright 2014 by The American College of Veterinary Surgeons.

  15. Temporomandibular joint dislocation due to acute propranolol intoxication

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    Abbas Aghabiklooei

    2010-07-01

    Full Text Available Abbas Aghabiklooei1, Homan Elahi2, Babak Mostafazadeh31Department of Medical Toxicology and Forensic Medicine, Iran University of Medical Sciences, Tehran, Iran; 2Firouzgar Hospital, Department of ENT, Tehran, Iran; 3Department of Medical Toxicology and Forensic Medicine, Shaheed Beheshty University of Medical Sciences, Tehran, IranAbstract: Temporomandibular joint (TMJ dislocation has not previously been reported as a complication of beta-blocker toxicity. We are reporting two cases of TMJ dislocation resulted from acute severe intoxication with pure propranolol (PPL for the first time. Bilateral TMJ dislocation happened in two patients who were admitted to intensive care unit with diagnosis of severe acute PPL toxicity. Clinical diagnosis of TMJ dislocation was obtained by physical examination. Successful reduction was performed for both patients without subsequent recurrence in two weeks following hospital discharge. Both of our subjects had no previous history of lower jaw dislocation. There was not any risk factor for dislocation such as convulsion during admission period, recent face trauma, or oral manipulation by the medical team. This study showed that TMJ dislocation may occur after severe acute PPL toxicity probably due to spastic contraction of the lateral pterygoid muscle. This is against previously mentioned hypothesis that stated masseteric muscles contraction as the main cause of a bilateral dislocated TMJ.Keywords: propranolol, toxicity, temporomandibular joint dislocation

  16. Macroscopic and microscopic analysis of the thumb carpometacarpal ligaments: a cadaveric study of ligament anatomy and histology.

    Science.gov (United States)

    Ladd, Amy L; Lee, Julia; Hagert, Elisabet

    2012-08-15

    Stability and mobility represent the paradoxical demands of the human thumb carpometacarpal joint, yet the structural origin of each functional demand is poorly defined. As many as sixteen and as few as four ligaments have been described as primary stabilizers, but controversy exists as to which ligaments are most important. We hypothesized that a comparative macroscopic and microscopic analysis of the ligaments of the thumb carpometacarpal joint would further define their role in joint stability. Thirty cadaveric hands (ten fresh-frozen and twenty embalmed) from nineteen cadavers (eight female and eleven male; average age at the time of death, seventy-six years) were dissected, and the supporting ligaments of the thumb carpometacarpal joint were identified. Ligament width, length, and thickness were recorded for morphometric analysis and were compared with use of the Student t test. The dorsal and volar ligaments were excised from the fresh-frozen specimens and were stained with use of a triple-staining immunofluorescent technique and underwent semiquantitative analysis of sensory innervation; half of these specimens were additionally analyzed for histomorphometric data. Mixed-effects linear regression was used to estimate differences between ligaments. Seven principal ligaments of the thumb carpometacarpal joint were identified: three dorsal deltoid-shaped ligaments (dorsal radial, dorsal central, posterior oblique), two volar ligaments (anterior oblique and ulnar collateral), and two ulnar ligaments (dorsal trapeziometacarpal and intermetacarpal). The dorsal ligaments were significantly thicker (p histologic appearance of capsular tissue with low cellularity. The dorsal deltoid ligament complex is uniformly stout and robust; this ligament complex is the thickest morphometrically, has the highest cellularity histologically, and shows the greatest degree of sensory nerve endings. The hypocellular anterior oblique ligament is thin, is variable in its location, and

  17. Epidemiology of Isolated Acromioclavicular Joint Dislocation

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    Claudio Chillemi

    2013-01-01

    Full Text Available Background. Acromioclavicular (AC joint dislocation is a common shoulder problem. However, information about the basic epidemiological features of this condition is scarce. The aim of this study is to analyze the epidemiology of isolated AC dislocation in an urban population. Materials and Methods. A retrospective database search was performed to identify all patients with an AC dislocation over a 5-year period. Gender, age, affected side and traumatic mechanism were taken into account. X-rays were reviewed by two of the authors and dislocations were classified according to the Rockwood’s criteria. Results. A total of 108 patients, with a mean age of 37.5 years were diagnosed with AC dislocation. 105 (97.2% had an isolated AC dislocation, and 3 (2.8% were associated with a clavicle fracture. The estimated incidence was 1.8 per 10000 inhabitants per year and the male-female ratio was 8.5 : 1. 50.5% of all dislocations occurred in individuals between the ages of 20 and 39 years. The most common traumatic mechanism was sport injury and the most common type of dislocation was Rockwood type III. Conclusions. Age between 20 and 39 years and male sex represent significant demographic risk factors for AC dislocation.

  18. [Trigeminal motor paralysis and dislocation of the temporo-mandibular joints].

    Science.gov (United States)

    Ohkawa, S; Yoshida, T; Ohsumi, Y; Tabuchi, M

    1996-07-01

    A 64-year-old woman with diabetes mellitus was admitted to our hospital with left hemiparesis of sudden onset. A brain MRI demonstrated a cerebral infarction in the ventral part of the right lower pons. When left hemiparesis worsened, she had dislocation of the temporo-mandibular joints repeatedly. Then, her lower jaw deviated to the right when she opened her mouth. Also, there was decreased contraction of the right masseter when she clenched her teeth. These findings suggest that there was trigeminal motor paralysis on the right side resulting from involvement of the intrapontine trigeminal motor nerve. She has no history of dislocation of the temporo-mandibular joints. An X-ray film showed that the temporo-mandibular joints were intact. Thus, it is possible that deviation of the lower jaw was the cause of this dislocation. We suspect that dislocation of the temporo-mandibular joints may occur as a complication of unilateral trigeminal motor paralysis. This has not been reported to our knowledge.

  19. Endobutton technique for the treatment of acute acromioclavicular joint dislocations

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    Raif Özden

    2014-06-01

    Full Text Available Objective: Acromioclavicular (AC joint dislocation is a common injury frequently affecting young athletes. The aim of this study is to evaluate postoperative functional results in cases diagnosed with acute AC joint dislocation stabilized with endobutton system. Methods: This fixation procedure has been applied on 10 patients. Indications of the technique included: a grade V AC joint dislocation (7 patients, and grade III AC joint dislocation (3 patient according to Rockwood classification. The coracoclavicular (CC interval and AC joint were reduced using two endobuttons. One endobutton was fitted on the clavicle and the second was placed at the undersurface of the coracoid. Outcomes were assessed with the Constant shoulder score and visual analog pain scale. Results: All the patients had powerful intraoperative fixation. Immediately after surgery, and 6 weeks, and 1 year postoperative radiographs showed adequate reduction of the CC distance and the AC joint. The mean Constant shoulder score was 89 (88–92 in the injured shoulder and 90 (88–93 in the uninjured shoulder. There was no statically significant difference between the injured and normal shoulder in terms of Constant shoulder score and there was no complication during the process. Conclusion: This technique is a safe and effective method for providing fixation for the AC joint.

  20. Clinical outcomes of the Cadenat procedure in the treatment of acromioclavicular joint dislocations.

    Science.gov (United States)

    Moriyama, Hiroaki; Gotoh, Masafumi; Mitsui, Yasuhiro; Yoshikawa, Eiichirou; Uryu, Takuya; Okawa, Takahiro; Higuchi, Fujio; Shirahama, Masahiro; Shiba, Naoto

    2014-01-01

    We report our clinical experience using the modified Cadenat method to treat acromioclavicular joint dislocation, and discuss the usefulness of this method. This study examined 6 shoulders in 6 patients (5 males, 1 female) who were diagnosed with acromioclavicular joint dislocation and treated with the modified Cadenat method at our hospital. Average age at onset was 49.3 years (26-78 years), average time interval from injury until surgery was 263.8 days (10 to 1100 days), and the average follow-up period was 21.7 months (12 to 42 months). Post-operative assessment was performed using plain radiographs to determine shoulder joint dislocation rate and Japanese Orthopaedic Association (JOA) score. The average post-operative JOA score was 94.1 points (91 to 100 points). The acromioclavicular joint dislocation rate improved from 148.7% (72 to 236%) before surgery to 28.6% (0 to 60%) after surgery. Conservative treatment has been reported to achieve good outcomes in acromioclavicular joint dislocations. However, many patients also experience chronic pain or a sensation of fatigue upon putting the extremity in an elevated posture, and therefore ensuring the stability of the acromioclavicular joint is crucial for highly active patients. In this study, we treated acromioclavicular joint dislocations by the modified Cadenat method, and were able to achieve favorable outcomes.

  1. Uncovertebral joint injury in cervical facet dislocation: the headphones sign

    Energy Technology Data Exchange (ETDEWEB)

    Palmieri, Francesco; Cassar-Pullicino, Victor N.; Dell' Atti, Claudia; Lalam, Radhesh K.; Tins, Bernhard J.; Tyrrell, Prudencia N.M.; McCall, Iain W. [Robert Jones and Agnes Hunt Orthopaedic and District Hospital, Department of Radiology, Oswestry, England (United Kingdom)

    2006-06-15

    The purpose of our study is to demonstrate the uncovertebral mal-alignment as a reliable indirect sign of cervical facet joint dislocation. We examined the uncovertebral axial plane alignment of 12 patients with unilateral and bilateral cervical facet joint dislocation (UCFJD and BCFJD, respectively), comparing its frequency to the reverse hamburger bun sign on CT and MR axial images. Of the seven cases with BCFJD, five clearly demonstrated the diagnostic reverse facet joint hamburger bun sign on CT and MR images, but in two cases this sign was not detectable. In the five cases with UCFJD, four demonstrated the reverse hamburger bun sign on both CT and MRI. In one case the reverse hamburger bun sign was not seen adequately with either image modality, but the facet dislocation was identified on sagittal imaging. The uncovertebral mal-alignment was detected in all 12 cases. Normally, the two components of the uncovertebral joint enjoy a concentric relationship that in the axial plane is reminiscent of the relationship of headphones with the wearer's head. We name this appearance the 'headphones' sign. Radiologists should be aware of the headphones sign as a reliable indicator of facet joint dislocation on axial imaging used in the assessment of cervical spine injuries. (orig.)

  2. In vivo recruitment patterns in the anterior oblique and dorsoradial ligaments of the first carpometacarpal joint

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    Halilaj, Eni; Rainbow, Michael J.; Moore, Douglas C.; Laidlaw, David H.; Weiss, Arnold-Peter C.; Ladd, Amy L.; Crisco, Joseph J.

    2015-01-01

    The anterior oblique ligament (AOL) and the dorsoradial ligament (DRL) are both regarded as mechanical stabilizers of the thumb carpometacarpal (CMC) joint, which in older women is often affected by osteoarthritis. Inferences on the potential relationship of these ligaments to joint pathomechanics are based on clinical experience and studies of cadaveric tissue, but their function has been studied sparsely in vivo. The purpose of this study was to gain insight into the functions of the AOL and DRL using in vivo joint kinematic data. The thumbs of 44 healthy subjects were imaged with a clinical computed tomography scanner in functional-task and thumb range-of-motion positions. The origins and insertion sites of the AOL and the DRL were identified on the 3D bone models and each ligament was modeled as a set of three fibers whose lengths were the minimum distances between insertion sites. Ligament recruitment, which represented ligament length as a percentage of the maximum length across the scanned positions, was computed for each position and related to joint posture. Mean AOL recruitment was lower than 91% across the CMC range of motion, whereas mean DRL recruitment was generally higher than 91% in abduction and flexion. Under the assumption that ligaments do not strain by more than 10% physiologically, our findings of mean ligament recruitments across the CMC range of motion indicate that the AOL is likely slack during most physiological positions, whereas the DRL may be taut and therefore support the joint in positions of CMC joint abduction and flexion. PMID:25964211

  3. Three-dimensional anatomical analysis of ligamentous attachments of the second through fifth carpometacarpal joints

    International Nuclear Information System (INIS)

    Nanno, Mitsuhiko; Sawaizumi, Takuya; Horiguchi, Gen; Ito, Hiromoto

    2007-01-01

    The purpose of this study is to identify, measure, and show the anatomic locations and areas of specific ligamentous attachments and paths of the second through fifth carpometacarpal (CMC) joints on a three-dimensional (3-D) surface model. Ten fresh-frozen cadaver wrists were used to dissect and identify the second through fifth CMC ligaments. The ligamentous attachments and whole bone surfaces were digitized three-dimensionally, and their areas were calculated. The attachments of each ligament were represented in a model in which their surfaces, as seen on computed tomography (CT), were overlaid with a digitized 3-D surface, and they were also visually demonstrated with a specific color on 3-D images of the bones. A total of 9 dorsal and 9 volar CMC ligaments and 1 CMC interosseous ligament were identified in the second through fifth CMC joints. An intra-articular ligament between the third and fourth metacarpals (MCs) and the capitate and hamate was also identified. In addition, 5 dorsal and 5 volar intermetacarpal ligaments and 3 intermetacarpal interosseous ligaments were also identified in the second through fifth intermetacarpal joints. A previously undescribed volar intermetacarpal ligament was found located between the third, fourth, and fifth MC bases. The anatomic 3-D attachment sites of the second through fifth CMC ligaments were visually depicted qualitatively, and their areas were quantified. This study has improved the knowledge and understanding of the normal anatomy and its impact on the mechanics of the second through fifth CMC joints. This 3-D information should facilitate the accurate assessment of radiographic images and the treatment of various injuries seen in the second through fifth CMC joints when performing ligament reconstruction, repair, osteochondral grafting, and arthroscopy. (author)

  4. Anterior fracture dislocation of the sacroiliac joint: A case report and literature review.

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    Xiao, Jianlin; Wang, Yang; Zhang, Minglei; Jiang, Rui; Zhu, Tongtong; Liu, Guangyao; Zuo, Jianlin

    2017-08-09

    Publications describing the diagnosis and treatment of anterior dislocation of the sacroiliac joint are scarce. We report the case a 19-year-old female at 8 weeks' gestation who presented with anterior fracture dislocation of the right sacroiliac joint, posterior fracture dislocation of the left sacroiliac joint (crescent fracture), and incomplete abortion resulting from high energy trauma. Orthopedic surgery involved standard anterior sacroiliac joint plating using an ilioinguinal approach combined with a modified Stoppa approach. Three attempts at complete abortion failed. Complete abortion was eventually achieved by dilatation and curettage two weeks after orthopedic surgery. Our findings reveal a need to improve techniques for diagnosis and treatment of anterior fracture dislocation of the sacroiliac joint, so greater attention can be paid to the rapid and effective management of associated comorbidities, and those resulting from the initial trauma.

  5. [Dislocation of the PIP-Joint - Treatment of a common (ball)sports injury].

    Science.gov (United States)

    Müller-Seubert, Wibke; Bührer, Gregor; Horch, Raymund E

    2017-09-01

    Background  Fractures or fracture dislocations of the proximal interphalangeal joint often occur during sports or accidents. Dislocations of the PIP-joint are the most common ligamentary injuries of the hand. As this kind of injury is so frequent, hand surgeons and other physicians should be aware of the correct treatment. Objectives  This paper summarises the most common injury patterns and the correct treatment of PIP-joint dislocations. Materials and Methods  This paper reviews the current literature and describes the standardised treatment of PIP-joint dislocations. Results  What is most important is that reposition is anatomically correct, and this should be controlled by X-ray examination. Depending on the instability and possible combination with other injuries (e. g. injury to the palmar plate), early functional physiotherapy of the joint or a short immobilisation period is indicated. Conclusions  Early functional treatment of the injured PIP-joint, initially using buddy taping, is important to restore PIP-joint movement and function. Depending on the injury, joint immobilisation using a K-wire may be indicated. Detailed informed consent is necessary to explain to the patient the severity of the injury and possible complications, such as chronic functional disorders or development of arthrosis. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Dislocation of the temporomandibular joint meniscus: contrast arthrography vs. computed tomography

    International Nuclear Information System (INIS)

    Thompson, J.R.; Christiansen, E.; Sauser, D.; Hasso, A.N.; Hinshaw, D.B. Jr.

    1985-01-01

    A prospective study to determine the accuracy of computed tomography (CT) for the diagnosis of dislocation of the temporomandibular joint (TMJ) meniscus was made by performing both CT and contrast arthrography on 18 joints suspected of meniscus dislocation. Arthography rather than surgery was chosen as the quality standard for comparing CT findings, as not all patients undergoing the studies underwent surgery. The results of each test were reported independently by the radiologist who obtained either all of the arthograms or all of the CT scans. For dislocation of the meniscus, there were excellent agreement between the two methods. CT seems to be nearly as accurate as arthrography for showing meniscus dislocation, is performed with lower x-ray exposure, and is noninvasive. Arthrograpy discloses more detailed information about the joint meniscus, such as perforation and maceration, and should continue to be used when this kind of information is clinically important

  7. Radiographic Shape of Foot With Second Metatarsophalangeal Joint Dislocation Associated With Hallux Valgus.

    Science.gov (United States)

    Kokubo, Tetsuro; Hashimoto, Takeshi; Suda, Yasunori; Waseda, Akeo; Ikezawa, Hiroko

    2017-12-01

    Second metatarsophalangeal (MTP) joint dislocation is associated with hallux valgus, and the treatment of complete dislocation can be difficult. The purpose of this study was to radiographically clarify the characteristic foot shape in the presence of second MTP joint dislocation. Weight-bearing foot radiographs of the 268 patients (358 feet) with hallux valgus were examined. They were divided into 2 groups: those with second MTP joint dislocation (study group = 179 feet) and those without dislocation (control group = 179 feet). Parameters measured included the hallux valgus angle (HVA), first-second intermetatarsal angle (IMA), second MTP joint angle, hallux interphalangeal angle (IPA), second metatarsal protrusion distance (MPD), metatarsus adductus angle (MAA), and the second metatarsal declination angle (2MDA). Furthermore, the dislocation group was divided into 3 subgroups according to second toe deviation direction: group M (medial type), group N (neutral type), and group L (lateral type). The IPA and the 2MDA were significantly greater in the study group than in the control group. By multiple comparison analysis, the IMA was greatest in group M and smallest in group L. The IPA was smaller and 2MDA greater in group N than in group L. The HVA and MAA in group L were greatest, and MPD in group L was smallest. The patients with second MTP joint dislocation associated with hallux valgus had greater hallux interphalangeal joint varus and a second metatarsal more inclined than with hallux valgus alone. The second toe deviated in a different direction according to the foot shape. Level III, retrospective comparative study.

  8. Osteoarthritis of the thumb carpometacarpal joint: Correlation of ultrasound appearances to disability and treatment response

    International Nuclear Information System (INIS)

    Mallinson, P.I.; Tun, J.K.; Farnell, R.D.; Campbell, D.A.; Robinson, P.

    2013-01-01

    Aim: To evaluate grading of thumb carpometacarpal joint (CMCJ) osteoarthritis (OA) using ultrasound, correlating findings with disability and treatment response. Materials and methods: Patients with symptomatic thumb OA attending for ultrasound-guided CMCJ steroid injection and a group of asymptomatic controls were recruited prospectively. Thumb CMCJ ultrasound was graded (osteophytes, joint-space narrowing, capsule size, and measured capsule size), and a Disabilities of the Arm Shoulder and Hand (DASH) questionnaire was completed for each patient. Symptomatic patients then underwent injection with DASH repeated 6 weeks post-treatment. Ultrasound features were correlated with the initial DASH disability score and response as defined by change in DASH 6 weeks after treatment. Results: Thirty-one patients with symptomatic OA and 37 asymptomatic controls were recruited. With the exception of osteophytes (p = 0.017), no statistically significant correlation was demonstrated between severity of ultrasound features and patient disability. However, all features demonstrated statistically significant higher grades in the symptomatic group compared to controls. Ultrasound grading did not have statistical correlation with treatment response. Conclusion: No correlation was found between the majority of ultrasound features and the clinical severity of OA or likely response to treatment. However, these features are significantly more common in the symptomatic population

  9. K-wire and tension band wire fixation in treating sternoclavicular joint dislocation

    Directory of Open Access Journals (Sweden)

    CHEN Qing-yu

    2011-02-01

    Full Text Available 【Abstract】Objective: To evaluate the feasibility and therapeutic effect of treating sternoclavicular joint dislocation by K-wire and tension band wire fixation, and to improve the safety and stability of this technique. Methods: This study consisted of 9 cases, 6 males and 3 females with the mean age of 25 years (range, 9-62 years. The causes were traffic accident in 7 cases, falling in 1 case and fight in 1 case. The duration from injury to operation was 2 hours to 7 days. There were 5 left dislocations and 4 right dislocations; 8 anterior dislocations and 1 posterior dislocation, including one combined with left scapular fracture and one with left olecranon fracture. Open reduction and internal fixation using K-wires and tension band wires were performed to treat dislocations. Results: All patients were followed up for 6 to 24 months, 10 months on average. According to Rockwood’s rating scale on postoperative sternoclavicular joint, 8 cases achieved excellent outcomes with an average score of 13.88, and the rest case achieved a good outcome with the score of 12. Anatomical reduction was obtained in all cases. There were no such postoperative complications as severe infection, injury to blood vessel and nerve, failure of fixation, etc. Patients were all satisfied with the anatomical reduction and functional recovery. Conclusions: The technique of K-wire and tension band wire fixation is safe, simple, effective, less invasive and has been successfully used in orthopedic surgery. It is effective in treating sternoclavicular joint dislocation though it has some disadvantages. Key words: Sternoclavicular joint; Dislocations; Bone wires; Fracture fixation, internal

  10. Long-standing temporomandibular joint dislocation: A rare experience

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    Kapil Malik

    2017-01-01

    Full Text Available Long-standing temporomandibular joint (TMJ dislocations persist for more than a month are most challenging to treat. The management of such condition varies widely, from closed reduction to complicated surgical procedures. The choice of an appropriate methodology is questionable. At present, there are no standard rules or conventions for the ideal strategy in different circumstances. This paper attempts to present the experience of managing two cases of long-standing TMJ dislocations.

  11. Dislocation of temporo-mandibular joint - an uncommon circumstance of occurrence: vaginal delivery.

    Science.gov (United States)

    El Bouazzaoui, Abderrahim; Labib, Smael; Derkaoui, Ali; Adnane Berdai, Mohammed; Bendadi, Azzeddine; Harandou, Mustapha

    2010-06-25

    Dislocation of temporo-mandibular joint (TMJ) is an infrequent disease but still spectacular. This disease consists of a permanent, to some extent complete disruption of the temporo-mandibular joint. These dislocations often occur in a context of yawning, and less frequently after a burst of laughing or relatively mild facial trauma (slap, punch on the chin). We report a case of TMJ occurring in an uncommon circumstance: vaginal delivery. A woman aged 24-years with no special past medical history; primipara was admitted in the Department of Maternity of the University Hospital Hassan II of Fez for an imminent delivery of a twin pregnancy. Ten minutes after admission, the patient delivered vaginally with episiotomy. She gave birth to twins weighing 2800 g and 2400 g. During labour, and due to efforts of crying, the patient developed a sudden and immediate loss of function of the temporo-mandibular joint, with difficulty of speaking, the mouth permanently opened and with the chin lowered and thrown forward. The examination found an empty glenoid fossa of the temporo-mandibular joint in both sides. The diagnosis of dislocation of the TMJ was established. A CT scan of facial bones was done, objectifying a bilateral dislocation of TMJ. The reduction of this dislocation was performed in the operating room under sedation.

  12. ASCOT: Autologous Bone Marrow Stem Cell Use for Osteoarthritis of the Thumb—First Carpometacarpal Joint

    Science.gov (United States)

    Buckley, Christina; Sugrue, Conor; Carr, Emma; O’Reilly, Aine; O’Neill, Shane; Carroll, Sean M.

    2017-01-01

    Background: The first carpometacarpal joint (CMCJ) in the hand is a commonly affected joint by osteoarthritis. It causes significant thumb base pain, limiting functional capacity. Microfracturing and application of autologous stem cells has been performed on large joints such as the knee but has never been evaluated for use in the smaller joints in the hand. Our aim was to determine the potential benefit of microfracturing and autologous bone marrow stem cells for treatment of osteoarthritis of the first CMCJ in the hand. Methods: All inclusion criteria were satisfied. Preoperative assessment by the surgeon, physiotherapist, and occupational therapist was performed. The first CMCJ was microfractured and the Bone Marrow Stem Cells were applied directly. Postoperatively, the patients were followed up for 1 year. Results: Fifteen patients met inclusion criteria; however, 2 patients were excluded due to postoperative cellulitis and diagnosis of De Quervain's tenosynovitis. The mean scores of the 13-patient preoperative and 1 year follow-up assessments are visual analog score at rest of 3.23–1.69 (P = 0.0292), visual analog score on activity of 7.92–4.23 (P = 0.0019), range of motion 45.77o–55.15o (P = 0.0195), thumb opposition score 7.62–9.23 (P = 0.0154), Disability of the Arm, Shoulder and Hand score of 51.67–23.08 (P = 0.0065). Strength improved insignificantly from 4.7 kg preoperatively to 5.53 kg at 12 months (P = 0.1257). All patients had a positive Grind test preoperatively and a negative test after 12 months. Conclusions: This innovative pilot study is a new approach to osteoarthritis of the thumb. PMID:29062653

  13. Evaluation of the mechanism and principles of management of temporomandibular joint dislocation. Systematic review of literature and a proposed new classification of temporomandibular joint dislocation.

    Science.gov (United States)

    Akinbami, Babatunde O

    2011-06-15

    Virtually all the articles in literature addressed only a specific type of dislocation. The aim of this review was to project a comprehensive understanding of the pathologic processes and management of all types of dislodgement of the head of the mandibular condyle from its normal position in the glenoid fossa. In addition, a new classification of temporomandibular joint dislocation was also proposed. A thorough computer literature search was done using the Medline, Cochrane library and Embase database. Key words like temporo-mandibular joint dislocation were used for the search. Additional manual search was done by going through published home-based and foreign articles. Case reports/series, and original articles that documented the type of dislocation, number of cases treated in the series and original articles. Treatment done and outcome of treatment were included in the study. A total of 128 articles were reviewed out which 79 were found relevant. Of these, 26 were case reports, 17 were case series and 36 were original articles. 79 cases were acute dislocations, 35 cases were chronic protracted TMJ dislocations and 311 cases were chronic recurrent TMJ dislocations. Etiology was predominantly trauma in 60% of cases and other causes contributed about 40%. Of all the cases reviewed, only 4 were unilateral dislocation. Various treatment modalities are outlined in this report as indicated for each type of dislocation. The more complex and invasive method of treatment may not necessarily offer the best option and outcome of treatment, therefore conservative approaches should be exhausted and utilized appropriately before adopting the more invasive surgical techniques.

  14. Double-button Fixation System for Management of Acute Acromioclavicular Joint Dislocation

    Science.gov (United States)

    Torkaman, Ali; Bagherifard, Abolfazl; Mokhatri, Tahmineh; Haghighi, Mohammad Hossein Shabanpour; Monshizadeh, Siamak; Taraz, Hamid; Hasanvand, Amin

    2016-01-01

    Background: Surgical treatments for acromioclavicular (AC) joint dislocation present with some complications. The present study was designed to evaluate the double-button fixation system in the management of acute acromioclavicular joint dislocation. Methods: This cross sectional study, done between February 2011 to June 2014, consisted of 28 patients who underwent surgical management by the double-button fixation system for acute AC joint dislocation. Age, sex, injury mechanism, dominant hand, side with injury, length of follow up, time before surgery, shoulder and hand (DASH), constant and visual analogue scale (VAS) scores, and all complications of the cases during the follow up were recorded. Results: The mean age of patients was 33.23±6.7 years. Twenty four patients (85.71%) were male and four (14.28%) were female. The significant differences were observed between pre-operation VAS, constant shoulder scores and post-operation measurements. There were not any significant differences between right and left coracoclavicular, but two cases of heterotrophic ossifications were recorded. The mean follow-up time was 16.17±4.38 months. Conclusion: According to the results, the double-button fixation system for management of acute acromioclavicular joint dislocation has suitable results and minimal damage to the soft tissues surrounding the coracoclavicular ligaments. PMID:26894217

  15. Artrodese do punho com fixação mínima preservando as articulações carpometacarpianas Wrist arthrodesis with minimal internal fixation preserving the carpometacarpal joints

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    Arlindo Gomes Pardini Júnior

    2010-01-01

    structures. In general, the results are very satisfactory, particularly for pain relief, and in the majority of cases, there is considerable functional improvement. Various techniques are described, with different methods of internal fixation, most of which include the carpometacarpal joints (CMJ in the fusion. The objective of this study is to evaluate the results of wrist arthrodesis through a technique which is simpler, more biological, more inexpensive, and does not involve the carpometacarpal joints. METHODS: 15 patients with wrist arthrodesis were evaluated (6 with sequelae of trauma, 4 Rheumatoid Arthritis, 3 Kienbock's grade IV, 1 Preiser and 1 panarthrosis. The technique consisted of the use of an iliac bone plate and internal fixation with Kirschner wires, avoiding the carpometacarpal joints. RESULTS: The evaluation was based on consolidation time (93% in 7 weeks; movements of the fingers and pronosupination; pinch and grasp strength; functional evaluation through the DASH questionnaire, pain and patient satisfaction. In general, the results were similar to those of other, more aggressive techniques, and the non-inclusion of the carpometacarpal joints did not affect the final result. CONCLUSION: wrist arthrodesis with fixation using Kirschner wires and the use of an iliac bone plate, preserving the carpometacarpal joints, gives good or excellent results which are similar to those of other techniques described. However it presents major advantages over other methods: it is less aggressive, less expensive, and does not have the inconvenience and complications associated the use of plates and screws.

  16. Posteromedial impingement (POMI) of the ankle: MR imaging features

    International Nuclear Information System (INIS)

    Koulouris, G.; Connell, D.

    2002-01-01

    Full text: The purpose of this study is to describe the normal MR Imaging appearance of the supporting ligaments of the first carpometacarpal joint in asymptomatic volunteers and the ligamentous injury in patients following dislocation. Three healthy volunteers underwent MR Imaging of the first carpometacarpal joint in order to describe the normal ligaments and optimise the scanning technique for assessment of this joint. Six patients underwent MR Imaging after injury to the ligament. All patients were injured after a fall in which the thumb was subluxed during hyperextension.The Anterior Oblique Ligament (AOL) was evaluated for abnormal morphology and signal intensity, including the site of the injury and the degree of tearing. Joint alignment was assessed for instability. The four ligaments felt to contribute to the stability of the first joint were reliably identified. The normal ligament is a continuous band of low signal running from one bone attachment to another. With injury, there is disruption of the ligament, hyperintensity and perforated stripping. The AOL was shown to be consistently injured after dislocation close to the metacarpal side. MR Imaging allows accurate evaluation of injuries of the AOL of the first carpometacarpal joint and identifies patients who would benefit from surgical reconstruction. Copyright (2002) Blackwell Science Pty Ltd

  17. Evaluation of the mechanism and principles of management of temporomandibular joint dislocation. Systematic review of literature and a proposed new classification of temporomandibular joint dislocation

    Directory of Open Access Journals (Sweden)

    Akinbami Babatunde O

    2011-06-01

    Full Text Available Abstract Background Virtually all the articles in literature addressed only a specific type of dislocation. The aim of this review was to project a comprehensive understanding of the pathologic processes and management of all types of dislodgement of the head of the mandibular condyle from its normal position in the glenoid fossa. In addition, a new classification of temporomandibular joint dislocation was also proposed. Method and materials A thorough computer literature search was done using the Medline, Cochrane library and Embase database. Key words like temporo-mandibular joint dislocation were used for the search. Additional manual search was done by going through published home-based and foreign articles. Case reports/series, and original articles that documented the type of dislocation, number of cases treated in the series and original articles. Treatment done and outcome of treatment were included in the study. Result A total of 128 articles were reviewed out which 79 were found relevant. Of these, 26 were case reports, 17 were case series and 36 were original articles. 79 cases were acute dislocations, 35 cases were chronic protracted TMJ dislocations and 311 cases were chronic recurrent TMJ dislocations. Etiology was predominantly trauma in 60% of cases and other causes contributed about 40%. Of all the cases reviewed, only 4 were unilateral dislocation. Various treatment modalities are outlined in this report as indicated for each type of dislocation. Conclusion The more complex and invasive method of treatment may not necessarily offer the best option and outcome of treatment, therefore conservative approaches should be exhausted and utilized appropriately before adopting the more invasive surgical techniques.

  18. Simultaneous Middle Third Clavicle Fracture and Type 3 Acromioclavicular Joint Dislocation; A Case Report

    Science.gov (United States)

    Solooki, Saeed; Azad, Ali

    2014-01-01

    Simultaneous middle third clavicle fracture and acromioclavicular joint dislocation is a rare combination injury, as a result of high-energy trauma. We report a patient with a middle third clavicle fracture and ipsilateral grade three-acromioclavicular joint dislocation, which is a rare combination. The patient wanted to get back to work as soon as possible, so the fracture was fixed with reconstruction plate after open reduction and plate contouring; and acromioclavicular joint dislocation was reduced and fixed with two full threaded cancellous screws. One screw was inserted through the plate to the coracoid process. Clinical and radiographic finding revealed complete union of clavicle fracture and anatomical reduction of acromioclavicular joint with pain free full joint range of motion one year after operation. PMID:25207318

  19. A modified surgical technique for reconstruction of an acute acromioclavicular joint dislocation

    OpenAIRE

    Marchie, Anthony; Kumar, Arun; Catre, Melanio

    2009-01-01

    We report a modified surgical technique for reconstruction of coracoclavicular and acromioclavicular ligaments after acute dislocation of acromioclavicular joint using suture anchors. We have repaired 3 consecutive type III acromioclavicular dislocations with good results. This technique is simple and safe and allows anatomical reconstruction of the ligaments in acute dislocations.

  20. Posterior treatment of delayed traumatic atlantoaxial joint dislocation with apofix internal fixation

    International Nuclear Information System (INIS)

    Qing Wei; Jiang Weimin; Shi Jinhui; Li Xuefeng; Yang Huilin; Tang Tiansi

    2010-01-01

    Objective: To assess the effect of posterior fixation and fusion with Apofix device for the treatment of delayed traumatic atlantoaxial joint dislocation. Methods: Eighteen patients with delayed traumatic atlantoaxial joint dislocation were included. Posterior fixation and fusion with Apofix device were performed. First step was one or two week skull traction. After the atlantoaxial joint dislocation had been reduced, the posterior fixation and fusion with Apofix was performed. Using local anaesthesia, atlantoaxial interval and posterior structure of atlas and dentata were exposed by midline operative approach. Apofix interlaminar clamps were placed at posterior arch of atlas and odontoid vertebral laminae, autologous iliac bone graft was placed for fusion. Then the device to proper position was pressurized and items locked. Results: All of the patients were followed up, the mean follow-up period was 38 months (13 ∼ 84 months). Fifteen patients obtained complete reduction, the others were partial reduction. Seventeen patients had successful fusion after 3 or 4 months, only 1 patient who had partial reduction had internal fixation loose and nonfusion, leading to recurrence of atlantoaxial joint dislocation. An occipitocervical fusion surgery was performed on this patient. As to neurological assessment, 16 patients had neurological deficit before operation, while 6 of them recovered completely after operation, another 10 patients' neurological status improved significantly. JOA score was improved from 9.5 pre-operative to 15.8 post-operative. Conclusion: Apofix internal fixation and fusion seems to be feasible in treatment of delayed traumatic atlantoaxial joint dislocation. Successful reduction before operation and proper treatment after operation is also important. (authors)

  1. A Case of Acromioclavicular Joint Dislocation Associated with Coracoid Process Fracture.

    Science.gov (United States)

    Nakamura, Yosuke; Gotoh, Masafumi; Mitsui, Yasuhiro; Shirachi, Isao; Yoshikawa, Eiichiro; Uryu, Takuya; Murakami, Hidetaka; Okawa, Takahiro; Higuchi, Fujio; Shiba, Naoto

    2015-01-01

    Rupture of any two or more parts of the superior shoulder suspensory complex (SSSC) including the distal clavicle, acromion, coracoid process, glenoid cavity of the scapula, acromioclavicular ligament, and coracoclavicular ligament is associated with shoulder girdle instability and is an indication for surgery. Here we report a case of acromioclavicular joint dislocation associated with coracoid process fracture. A 48-year-old man sustained a hard blow to the left shoulder from a fall, and simple radiography detected a coracoid process fracture and acromioclavicular joint dislocation. The injury consisted of a rupture of two parts of the SSSC. For the coracoid process fracture, osteosynthesis was performed using hollow cancellous bone screws. For the acromioclavicular joint dislocation, hook plate fixation and the modified Neviaser's procedure were performed. The bone healed well 5 months after surgery, at which time the screws were removed. At 18 months after initial surgery, the coracoid process fracture had healed with a 10% rate of dislocation on radiography, and the patient currently has no problem performing daily activities, no range of motion limitations, and a Japanese Orthopaedic Association scale score of 93.

  2. Double-button Fixation System for Management of Acute Acromioclavicular Joint Dislocation

    Directory of Open Access Journals (Sweden)

    Ali Torkaman

    2016-01-01

    Full Text Available Background: Surgical treatments for acromioclavicular (AC joint dislocation present with some complications. The present study was designed to evaluate the double-button fixation system in the management of acute acromioclavicular joint dislocation. Methods: This cross sectional study, done between February 2011 to June 2014, consisted of 28 patients who underwent surgical management by the double-button fixation system for acute AC joint dislocation. Age, sex, injury mechanism, dominant hand, side with injury, length of follow up, time before surgery, shoulder and hand (DASH, constant and visual analogue scale (VAS scores, and all complications of the cases during the follow up were recorded. Results: The mean age of patients was 33.23±6.7 years. Twenty four patients (85.71% were male and four (14.28% were female. The significant differences were observed between pre-operation VAS, constant shoulder scores and post-operation measurements (P=0.001, P=0.0001, P=0.0001, respectively. There were not any significant differences between right and left coracoclavicular (P=0.238, but two cases of heterotrophic ossifications were recorded. The mean follow-up time was 16.17±4.38 months. Conclusion: According to the results, the double-button fixation system for management of acute acromioclavicular joint dislocation has suitable results and minimal damage to the soft tissues surrounding the coracoclavicular ligaments.

  3. Temporo-mandibular joint dislocation: an unusual complication of transoesophageal echocardiography.

    Science.gov (United States)

    Anantharam, Brijesh; Chahal, Navtej; Stephens, Nigel; Senior, Roxy

    2010-03-01

    Temporo-mandibular joint (TMJ) dislocation is an unusual complication of transoesophageal echocardiography (TEE). We report a rare case of bilateral TMJ dislocation in an 84-year-old man prior to DC cardioversion (DCCV) for atrial flutter. Shortly after TEE and DCCV, the patient complained of bilateral facial pain. An orthopantomogram revealed bilateral TMJ dislocation. A closed reduction was performed by maxillo-facial surgeons under intravenous anaesthesia. Although very uncommon, the physician should be aware of the complication and its management.

  4. A modified surgical technique for reconstruction of an acute acromioclavicular joint dislocation

    Science.gov (United States)

    Marchie, Anthony; Kumar, Arun; Catre, Melanio

    2009-01-01

    We report a modified surgical technique for reconstruction of coracoclavicular and acromioclavicular ligaments after acute dislocation of acromioclavicular joint using suture anchors. We have repaired 3 consecutive type III acromioclavicular dislocations with good results. This technique is simple and safe and allows anatomical reconstruction of the ligaments in acute dislocations. PMID:20671868

  5. Effects of hook plate on shoulder function after treatment of acromioclavicular joint dislocation.

    Science.gov (United States)

    Chen, Chang-Hong; Dong, Qi-Rong; Zhou, Rong-Kui; Zhen, Hua-Qing; Jiao, Ya-Jun

    2014-01-01

    Internal fixation with hook plate has been used to treat acromioclavicular joint dislocation. This study aims to evaluate the effect of its use on shoulder function, to further analyze the contributing factors, and provide a basis for selection and design of improved internal fixation treatment of the acromioclavicular joint dislocation in the future. A retrospective analysis was performed on patients treated with a hook plate for acromioclavicular joint dislocation in our hospital from January 2010 to February 2013. There were 33 cases in total, including 25 males and 8 females, with mean age of 48.27 ± 8.7 years. There were 29 cases of Rockwood type III acromioclavicular dislocation, 4 cases of type V. The Constant-Murley shoulder function scoring system was used to evaluate the shoulder function recovery status after surgery. Anteroposterior shoulder X-ray was used to assess the position of the hook plate, status of acromioclavicular joint reduction and the occurrence of postoperative complications. According to the Constant-Murley shoulder function scoring system, the average scores were 78 ± 6 points 8 to 12 months after the surgery and before the removal of the hook plate, the average scores were 89 ± 5 minutes two months after the removal of hook plate. Postoperative X-ray imaging showed osteolysis in 10 cases (30.3%), osteoarthritis in six cases (18.1%), osteolysis associated with osteoarthritis in four cases(12.1%), and steel hook broken in one case (3%). The use of hook plate on open reduction and internal fixation of the acromioclavicular joint dislocation had little adverse effect on shoulder function and is an effective method for the treatment of acromioclavicular joint dislocation. Osteoarthritis and osteolysis are the two common complications after hook plate use, which are associated with the impairment of shoulder function. Shoulder function will be improved after removal of the hook plate.

  6. Operative treatment of acromioclavicular joint dislocation: a new technique with suture anchors

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    Zhang Jingwei

    2014-07-01

    Full Text Available 【Abstract】Objective: To evaluate clinical outcome of suture anchors in strengthening both acromioclavicular and coracoclavicular ligaments in the surgical treatment of acromioclavicular joint dislocation. Methods: Twenty-eight patients with acute traumatic Rockwood III, IV and V dislocations of the acromioclavicular joint surgically treated at our institute between October 2010 and January 2012 were recruited. All patients underwent open reduction combined with suture anchors. Function was evaluated using the ConstantMurley shoulder score. Clinical and radiographic shoulder ratings were evaluated using Taft criteria at 3, 6 and 12 months. Results:Two cases with fixation loosening were not included in final statistical analysis. Other patients obtained full joint reposition on immediate postoperative radiographs. Follow-up was performed with an average of 15.6 months (range, 12-19. After early range of motion exercises, 96.2% of the patients (25/26 could abduct and elevate their shoulders more than 90 degrees within postoperative 3 months. There was no infection. Average Constant-Murley score was 96.3 points (range, 94-100 and mean Taft shoulder rating was 10.7 points (range, 8-12 at 12 months. Conclusion: The suture anchor is a relatively simple technique and can avoid screw removal which is helpful in reconstructing both acromioclavicular and coracoclavicular ligaments in acute traumatic acromioclavicular joint dislocation. Key words: Acromioclavicular joint; Dislocations; Surgery; Suture anchors

  7. K-wire and tension band wire fixation in treating sternoclavicular joint dislocation.

    Science.gov (United States)

    Chen, Qing-yu; Cheng, Shao-wen; Wang, Wei; Lin, Zhong-qin; Zhang, Wei; Kou, Dong-quan; Shen, Yue; Ying, Xiao-zhou; Cheng, Xiao-jie; Lv, Chuan-zhu; Peng, Lei

    2011-02-01

    To evaluate the feasibility and therapeutic effect of treating sternoclavicular joint dislocation by K-wire and tension band wire fixation, and to improve the safety and stability of this technique. This study consisted of 9 cases, 6 males and 3 females with the mean age of 25 years (range, 9-62 years). The causes were traffic accident in 7 cases, falling in 1 case and fight in 1 case. The duration from injury to operation was 2 hours to 7 days. There were 5 left dislocations and 4 right dislocations; 8 anterior dislocations and 1 posterior dislocation, including one combined with left scapular fracture and one with left olecranon fracture. Open reduction and internal fixation using K-wires and tension band wires were performed to treat dislocations. All patients were followed up for 6 to 24 months, 10 months on average. According to Rockwood's rating scale on postoperative sternoclavicular joint, 8 cases achieved excellent outcomes with an average score of 13.88, and the rest case achieved a good outcome with the score of 12. Anatomical reduction was obtained in all cases. There were no such postoperative complications as severe infection, injury to blood vessel and nerve, failure of fixation, etc. Patients were all satisfied with the anatomical reduction and functional recovery. The technique of K-wire and tension band wire fixation is safe, simple, effective, less invasive and has been successfully used in orthopedic surgery. It is effective in treating sternoclavicular joint dislocation though it has some disadvantages.

  8. A new technique for repair of a dislocated sternoclavicular joint using a sternal tension cable system.

    Science.gov (United States)

    Janson, Jacques T; Rossouw, Gawie J

    2013-02-01

    An unstable anterior or posterior sternoclavicular joint dislocation can cause severe morbidity with poor shoulder movement and strength. These dislocations need to be repaired, which can be challenging. Many different procedures have been described to obtain a stable joint fixation with varying results. We report a new technique for repairing a sternoclavicular joint dislocation by using a figure-of-eight sternal cable system. This procedure is relatively simple and reproducible to create a stable and functional sternoclavicular joint. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  9. Simultaneous of Mid Third Clavicle Fracture and Type 3 Acromioclavicular Joint Dislocation; A Case Report

    Directory of Open Access Journals (Sweden)

    Saeed Solooki

    2014-03-01

    Full Text Available Simultaneous mid third clavicle fracture and acromioclavicular joint dislocation is a rare combination injury, as a result of high-energy trauma. We report a patient with a middle third clavicle fracture and ipsilateral grade three-acromioclavicular joint dislocation, which is a rare combination. The patient wanted to get back to work as soon as possible, so the fracture was fixed with reconstruction plate after open reduction and plate contouring; and acromioclavicular joint dislocation was reduced and fixed with two full threaded cancellous screws. One screw was inserted through the plate to the coracoid process. Clinical and radiographic finding revealed complete union of clavicle fracture and anatomical reduction of acromioclavicular joint with pain free full joint range of motion one year after operation.

  10. Simultaneous of Mid Third Clavicle Fracture and Type 3 Acromioclavicular Joint Dislocation; A Case Report

    Directory of Open Access Journals (Sweden)

    Saeed Solooki

    2014-03-01

    Full Text Available   Simultaneous mid third clavicle fracture and acromioclavicular joint dislocation is a rare combination injury, as a result of high-energy trauma. We report a patient with a middle third clavicle fracture and ipsilateral grade three-acromioclavicular joint dislocation, which is a rare combination. The patient wanted to get back to work as soon as possible, so the fracture was fixed with reconstruction plate after open reduction and plate contouring; and acromioclavicular joint dislocation was reduced and fixed with two full threaded cancellous screws. One screw was inserted through the plate to the coracoid process. Clinical and radiographic finding revealed complete union of clavicle fracture and anatomical reduction of acromioclavicular joint with pain free full joint range of motion one year after operation.

  11. Dislocation of temporo-mandibular joint - an uncommon circumstance of occurrence: vaginal delivery

    Directory of Open Access Journals (Sweden)

    Abderrahim El Bouazzaoui

    2010-06-01

    Full Text Available Dislocation of temporo-mandibular joint (TMJ is an infrequent disease but still almost spectacular. This disease consists of a permanent, to some extent complete disruption of the temporo-mandibular joint. These dislocations often occurs in a context of yawning, and less frequently after a burst of laughing or relatively mild facial trauma (slap, punch on the chin.We report a case of TMJ occurring in an uncommon circumstance : vaginal delivery. A young woman aged 24-years with no special past medical history; primipara was admitted in the Department of Maternity of the University Hospital Hassan II of Fez for an imminent delivery of a twin pregnancy. Obstetrical analgesia was not possible so the parturient cried in a strong manner during labour. Ten minutes after admission, the patient delivered vaginally with episiotomy. She gave birth to twins weighing 2800g and 2400g. During labour, and effort of crying, the patient presented a sudden and immediate loss of function of the temporo-mandibular joint, with difficulty of speaking, the mouth permanently opened, with the chin lowered and thrown forward. The examination found an emptiness of the glenoid fossa of the temporo-mandibular joint in both sides. The diagnosis of dislocation of the TMJ has established. Performance of special radiologic screening to study the TM was technically not possible. A CT scan of facial bones has been achieved so objectifying a bilateral dislocation of TMJ. The reduction of this dislocation was performed in the operating room under sedation

  12. Occult external iliac vein injury after anterior dislocation of the sacroiliac joint in adult patient

    Directory of Open Access Journals (Sweden)

    Yueju Liu

    2017-03-01

    Full Text Available Anterior dislocation of the sacroiliac joint, characterized by dislocation of the ilium anterior to the sacrum, is a subtype of complete posterior pelvic ring disruption. This injury occurs mostly in children. We present an adult patient with anterior dislocation of the sacroiliac joint. It was associated with numerous complications. To the best of our knowledge, it is only the second case reported in the literature.

  13. [Bilateral chronic dislocation of the temporomandibular joints and Meige syndrome].

    Science.gov (United States)

    Arzul, L; Henoux, M; Marion, F; Corre, P

    2015-04-01

    Chronic dislocation of the temporo-mandibular joint (TMJ) is rare. It occurs when an acute dislocation is left untreated, in certain situations, including severe illness, neurologic or psychiatric diseases or prolonged oral intubation. A 79 years old woman, with Meige syndrome, suffered from bilateral dislocation of the TMJ for over 1 year. Surgical repositioning of the mandibular condyles and temporal bone eminectomy were performed. At the 18 postoperative months control, no recurrence has been noted. Treatment of chronic TMJ dislocations often requires a surgical procedure. Manual reduction, even under general anaesthesia, often fails because of severe muscular spasm and periarticular fibrotic changes. The management of this disorder is still controversial. We review available surgical procedures. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  14. Ligamentous and capsular restraints to experimental posterior elbow joint dislocation

    DEFF Research Database (Denmark)

    Deutch, S.R.; Olsen, B.S.; Jensen, S.L.

    2003-01-01

    the anterior capsule and the lateral collateral ligament complex (LCLC), whereas in the flexed elbow the anterior capsule did not have a stabilizing effect. In flexed joint positions, the LCLC seems to be the only immediate stabilizer against PEFR, and thereby against posterolateral instability and possibly...... against posterior dislocation. The medial collateral ligament did not have any immediate stabilizing effect, but it prevented the final step of the posterior dislocation....

  15. Differences Regarding Branded HA in Italy, Part 2: Data from Clinical Studies on Knee, Hip, Shoulder, Ankle, Temporomandibular Joint, Vertebral Facets, and Carpometacarpal Joint

    Science.gov (United States)

    Migliore, A.; Bizzi, E.; De Lucia, O.; Delle Sedie, A.; Tropea, S.; Bentivegna, M.; Mahmoud, A.; Foti, C.

    2016-01-01

    OBJECTIVES The aim of the current study is to collect scientific data on all branded hyaluronic acid (HA) products in Italy that are in use for intra-articular (IA) injection in osteoarthritis (OA) compared with that reported in the leaflet. METHODS An extensive literature research was performed for all articles reporting data on the IA use of HA in OA. Selected studies were taken into consideration only if they are related to products based on HAs that are currently marketed in Italy with the specific joint indication for IA use in patients affected by OA. RESULTS Sixty-two HA products are marketed in Italy: 30 products are indicated for the knee but only 8 were proved with some efficacy; 9 products were effective for the hip but only 6 had hip indication; 7 products proved to be effective for the shoulder but only 3 had the indication; 5 products proved effective for the ankle but only one had the indication; 6 products were effective for the temporomandibular joint but only 2 had the indication; only 2 proved effective for vertebral facet joints but only 1 had the indication; and 5 products proved effective for the carpometacarpal joint but only 2 had the indication. CONCLUSIONS There are only a few products with some evidences, while the majority of products remain without proof. Clinicians and regulators should request postmarketing studies from pharmaceuticals to corroborate with that reported in the leaflet and to gather more data, allowing the clinicians to choose the adequate product for the patient. PMID:27279754

  16. Management of acute dislocation of the temporomandibular joint in dental practice.

    LENUS (Irish Health Repository)

    McGoldrick, David M

    2010-12-01

    Acute dislocation of the temporomandibular joint is a situation that, although rare, may present to the dentist in practice at any time. A number of activities, such as removal of a tooth, may cause dislocation. The event is painful and distressing for the patient, their family and the dental team. Prompt management minimises discomfort, distress and long-term morbidity to the patient. We describe the aetiology of acute dislocation and outline a number of techniques that will aid the clinican in dealing with this event.

  17. Changes of the hip joints associated with chronic subluxation and dislocation: CT and plain radiography analysis

    International Nuclear Information System (INIS)

    Yang, Ik; Ryu, Kyung Nam; Lee, Sun Wha; Choi, Woo Suk; Lee, Eil Seong

    1993-01-01

    Secondary osteoarthritis of the hip joint is a common disease and is frequently followed by chronic subluxation and dislocation. Twenty four cases of the secondary osteoarthritis associated with chronic subluxation and dislocation of the hip joints were evaluated with plain radiography and computed tomography. We retrospectively analyzed 1) the osteoarthritis and calcification of the acetabular labrum, 2) the thickness of the quadrilateral plate of the ilium, and 3) anteroposterior diameter of the acetabulum. The changes of the hip joints in subluxation (n=14) revealed ossification of the acetabular labrum in 12 cases (86%), thickening of the quadrilateral plate of the ilium in 11 cases (78%) but anteroposterior diameter of the acetabulum was not changed. The changes of the hip joints in dislocation (n=10) revealed no evidence of the ossification of the acetabular labrum, thickening of the quadrilateral plate of the ilium in 10 cases (100%) and decreased anteroposterior diameter of the acetabulum. We conclude that CT findings of subluxation and dislocation of the hip joints can be helpful in the evaluation of the secondary osteoarthritis of the hip joints

  18. Combined acromioclavicular joint dislocation and coracoid avulsion in an adult.

    Science.gov (United States)

    Naik, Monappa; Tripathy, Sujit Kumar; Goyal, Saumitra; Rao, Sarath K

    2015-05-20

    Avulsion fracture of coracoid process with acromioclavicular joint dislocation is extremely rare. We report a case of coracoid avulsion with acromioclavicular disruption in a 24-year-old man who sustained injuries in a road traffic accident. Although acromioclavicular (AC) dislocation was obvious from an initial radiograph, coracoid avulsion was picked up in a CT scan. Open reduction and internal fixations of the coracoid with a 4 mm cannulated screw, an AC joint with two K-wires and an anchor suture, resulted in rapid recovery. The patient had complete range of shoulder movements at the end of 3 months and he resumed his professional activities. After 1 year, he had normal shoulder movement without any functional limitations. 2015 BMJ Publishing Group Ltd.

  19. Changes in surgical procedures for acromioclavicular joint dislocation over the past 30 years.

    Science.gov (United States)

    Takase, Katsumi; Yamamoto, Kengo

    2013-10-01

    Generally, surgical treatment is recommended for Rockwood type 5 traumatic acromioclavicular joint dislocations. Since 1980, the authors have performed the modified Dewar procedure, the modified Cadenat procedure, and anatomical reconstruction of the coracoclavicular ligaments for this injury. The goal of this study was to determine the ideal surgical procedure for acromioclavicular joint dislocations by comparing these 3 procedures. The modified Dewar procedure was performed on 55 patients (Dewar group), the modified Cadenat procedure was performed on 73 patients (Cadenat group), and anatomical reconstruction of the coracoclavicular ligaments was performed on 11 patients (reconstruction group). According to the UCLA scoring system, therapeutic results averaged 27.3 points in the Dewar group, 28.2 in the Cadenat group, and 28.4 in the reconstruction group. The incidence of residual subluxation or dislocation in the acromioclavicular joint was evaluated at final radiographic follow-up. Subluxation occurred in 21 patients in the Dewar group, 18 in the Cadenat group, and 3 in the reconstruction group. Dislocation occurred in 3 patients in the Dewar group. Osteoarthritic changes in the acromioclavicular joint occurred in 20 patients in the Dewar group, 9 in the Cadenat group, and 1 in the reconstruction group. The modified Cadenat procedure can provide satisfactory therapeutic results and avoid postoperative failure or loss of reduction compared with the modified Dewar procedure. However, the modified Cadenat procedure does not anatomically restore the coracoclavicular ligaments. Anatomic restoration of both coracoclavicular ligaments can best restore acromioclavicular joint function. Copyright 2013, SLACK Incorporated.

  20. A Rare Case of Morel-Lavallee Syndrome Complicating an Anterior Dislocation of Hip Joint.

    Science.gov (United States)

    Nekkanti, Supreeth; Vijay, C; Theja, Sujana; Shankar, R Ravi; Verma, Anubhav

    2016-01-01

    Hip dislocations are serious injuries as hip joint is an extremely stable joint. It requires a significant amount of force to produce such an injury. Anterior dislocations are uncommon. Potential complications of anterior hip dislocations are a neurovascular injury to femoral vessels or acetabular fractures. We report a rare late complication of Morel-Lavallee syndrome occurring 3 weeks after an anterior dislocation of the hip in a 43-year-old male. The patient presented to us with history. Morel-Lavallee syndrome is a rare complication. However if diagnosed early can be successfully treated with minimal burden to the patient. The authors recommend surgeons to have a high index of suspicion for this syndrome and a stringent follow-up examination of the patient.

  1. The thumb carpometacarpal joint: curvature morphology of the articulating surfaces, mathematical description and mechanical functioning.

    Science.gov (United States)

    Dathe, Henning; Dumont, Clemens; Perplies, Rainer; Fanghänel, Jochen; Kubein-Meesenburg, Dietmar; Nägerl, Hans; Wachowski, Martin M

    2016-01-01

    The purpose is to present a mathematical model of the function of the thumb carpometacarpal joint (TCMCJ) based on measurements of human joints. In the TCMCJ both articulating surfaces are saddle-shaped. The aim was to geometrically survey the shapes of the articulating surfaces using precise replicas of 28 TCMCJs. None of these 56 articulating surfaces did mathematically extend the differential geometrical neighbourhood around the main saddle point so that each surface could be characterised by three main parameters: the two extreme radii of curvature in the main saddle point and the angle between the saddles' asymptotics (straight lines). The articulating surfaces, when contacting at the respective main saddle points, are incongruent. Hence, the TCMCJ has functionally five kinematical degrees of freedom (DOF); two DOF belong to flexion/extension, two to ab-/adduction. These four DOF are controlled by the muscular apparatus. The fifth DOF, axial rotation, cannot be adjusted but stabilized by the muscular apparatus so that physiologically under compressive load axial rotation does not exceed an angle of approximately ±3°. The TCMCJ can be stimulated by the muscular apparatus to circumduct. The mechanisms are traced back to the curvature incongruity of the saddle surfaces. Hence we mathematically proved that none of the individual saddle surfaces can be described by a quadratic saddle surface as is often assumed in literature. We derived an algebraic formula with which the articulating surfaces in the TCMCJ can be quantitatively described. This formula can be used to shape the articulating surfaces in physiologically equivalent TCMCJ-prostheses.

  2. Semi-quantitative SPECT for anterior dislocation of the disc in the temporo-mandibular joint

    Energy Technology Data Exchange (ETDEWEB)

    Oesterreich, F.U.; Jend-Rossmann, I.; Jend, H.H.; Triebel, H.J.

    1987-01-01

    SPECT-examination of the TMJ using 99m-Tc-MDP was performed in 43 patients with arthrographically proven anterior dislocation of the disc and in 30 normals. The results were evaluated visually and also in a semi-quantitative manner that took account of relative 99m Tc activity in the TMJ and of the age of the patient. In the presence of arthrographically proven anterior, but reversible, disc dislocation, the semi-quantitative method proved positive in 75% of cases (28 cases). In joints with fixed anterior dislocation (29 cases), bone changes were demonstrated in 26%. Visual evaluation was positive in 50% of reversible, and in 72% of non-reversible dislocations. Semi-quantitative SPECT of the TMJ is excellent for demonstrating bone reaction resulting from TMJ dysfunction and for indicating the severity of the joint abnormality.

  3. Simultaneous Dorsal Dislocation of the Proximal and Distal Interphalangeal Joints in the Middle Finger: A Case Report

    Directory of Open Access Journals (Sweden)

    Mohamed Ali Sbai

    2017-07-01

    Full Text Available Introduction Dorsal dislocation of a proximal or distal interphalangeal joint is a common clinical problem. However, simultaneous dislocation of both joints in the same digit is rare. Case Presentation A 32-year-old male injured his left hand third finger while biking. Examination revealed a stepladder deformity. Neurovascular examination was normal. Radiographs revealed dorsal dislocation of both the proximal and distal interphalangeal joints. The finger was reduced easily by longitudinal manual traction under the digital block. The finger was splinted in the intrinsic plus position for 3 weeks accompanied with active range of motion. After 6 months, the patient returned to normal sporting activity without limitation of motion. Conclusions In case of simultaneous dorsal dislocation of a proximal and distal interphalangeal joint, closed reduction is the treatment of choice and it could result in good and normal range of motion.

  4. Clinical and Plain Radiograph Pattern of Joint Dislocations and ...

    African Journals Online (AJOL)

    Plain radiograph is an integral part of early assessment of patients' evaluation, though newer imaging modalities such as magnetic resonance imaging (MRI), ... Conclusion: The shoulder joint is the most frequently dislocated and a conventional plain radiograph is still valuable as a first line investigative modality in ...

  5. Surgical treatment of a concurrent type 5 acromioclavicular joint dislocation and a failed anterior glenohumeral joint stabilization

    OpenAIRE

    Rashid, Abbas; Lawrence, Christopher; Tytherleigh-Strong, Graham

    2016-01-01

    Traumatic glenohumeral joint dislocation and acromioclavicular joint subluxations tend to occur in young active males. Use of the coracoid process either as a transfer in recurrent instability or in suspensory reconstructions of the coracoclavicular ligaments have gained popularity. However this requires careful consideration in the event of concomitant injuries if they both require surgery.

  6. Avascular necrosis of the trapezoid bone following carpometacarpal arthroplasty.

    Science.gov (United States)

    Kane, Patrick; Waryasz, Greg; Katarincic, Julie

    2014-03-03

    A 58-year-old female developed avascular necrosis of her trapezoid approximately 3 months after undergoing carpometacarpal arthroplasty. The patient was treated conservatively with immobilization and had complete resolution of her clinical symptoms during her year of follow-up. Additionally, radiographic examination showed complete restoration of the height of her trapezoid approximately 1 year after the index procedure. Avascular necrosis of the trapezoid is extremely rare with very few cases described in the literature. This is the first description of avascular necrosis following carpometacarpal arthroplasty.

  7. Osteoarthritis of the carpometacarpal joint of the thumb: a new MR imaging technique for the standardized detection of relevant ligamental lesions

    Energy Technology Data Exchange (ETDEWEB)

    Dumont, Clemens [University Medical Center Goettingen, Department of Trauma Surgery, Plastic and Reconstructive Surgery, Goettingen (Germany); Georg-August-Universitaet, Department of Trauma Surgery, Plastic and Reconstructive Surgery, Goettingen (Germany); Lerzer, Sebastian; Tezval, Mohammad; Stuermer, Klaus Michael [University Medical Center Goettingen, Department of Trauma Surgery, Plastic and Reconstructive Surgery, Goettingen (Germany); Vafa, Morad Ali; Lotz, Joachim [University Medical Center Goettingen, Department of Diagnostic Radiology and Interventional Radiology, Goettingen (Germany); Dechent, Peter [University Medical Center Goettingen, MR-Research in Neurology and Psychiatry, Department of Cognitive Neurology, Goettingen (Germany)

    2014-10-15

    To assess ligament lesions and subluxations of the carpometacarpal joints of the thumbs (CMC I) of asymptomatic volunteers and of patients with CMC I osteoarthritis using advanced magnetic resonance imaging (MRI). A total of 20 CMC I joints of 14 asymptomatic volunteers (6 x both sides) and 28 CMC I joints of 22 patients (6 x both sides) with symptomatic and X-ray-diagnosed osteoarthritis of CMC I joints were studied. During extension, flexion, abduction and adduction of the thumb, the anterior oblique (AOL), intermetacarpal (IML), posterior oblique (POL) and dorsal radial (DRL) ligaments were evaluated using 3-T MRI on two standard planes, and translation of metacarpal I (MC I) was assessed. The MRI demonstrated that ligament lesions of the AOL and IML are frequent. Isolated rupture of the AOL was found in 6 of 28 (21 %), combined rupture of the AOL + IML in 5 of 28 (18 %) and isolated IML rupture in 4 of 28 (14 %) joints. The patients had a significantly increased dorsal translation of MC I during extension with a median of 6.4 mm vs. 5.4 mm in asymptomatic volunteers (p < 0.05). MRIs of CMC I in two standardized planes frequently show combined ligament ruptures. The dorsal subluxation of MC I, which is increased in patients, correlates with OA severity based on X-ray and can be quantified by MRI. For joint-preserving surgical procedures and for prosthesis implantation of the CMC I, we recommend performing an MRI in two planes of the thumb - extension and abduction - to evaluate the ligaments and dorsal subluxation of MC I. (orig.)

  8. Operative Versus Non-operative Treatment of Grade III Acromioclavicular Joint Dislocations and the Use of SurgiLig: a Retrospective Review.

    Science.gov (United States)

    Younis, Fizan; Ajwani, Sanil; Bibi, Asia; Riley, Eleanor; Hughes, Peter J

    2017-12-30

    Acromioclavicular joint dislocations are common shoulder girdle injuries. The treatment of grade III acromioclavicular joint dislocations is controversial. Furthermore, the literature on the use of the Sur-giligTM synthetic ligament for reconstruction of dislocations is sparse. This retrospective review aimed to establish whether operative treatment was superior to non-operative treatment in grade III acromioclavicular joint dislocations treated at our institute over a 5-year period. We also reviewed the effectiveness of reconstruction with SurgiligTM after acute and chronic dislocations across all grades of acromioclavicular joint dislocations. Twenty-five patients completed full follow-up with grade III dislocations. The mean follow-up in the operated group was 3.56 years and in the non-operated group this was 3.29 years. The mean Oxford Shoul-der Score (OSS) in the operated group was 39.8, whereas the mean OSS in the non-operated group was 45.9 (p=0.01). The mean pain score in the operated group was 2.2, and in the non-operated group this was 1.6. The mean satisfaction score in the operated group was 8.2 and that in the non-operated group was 7.8. There was no statistically significant difference in pain or satisfaction scores. In respect to the cohort treated with Surg-iligTM synthetic ligament, 22 patients across all grades of dislocations had this procedure performed. The mean post-operative Oxford Shoulder Score (OSS) was 40. 1. Non-operative treatment is not inferior to operative treatment for grade III acromioclavicular joint dislocations. The data from this study demonstrat-ed that the non-operated group had superior Ox-ford Shoul-der Scores that were statistically significant. 2. Additionally, the use of the SurgiligTM ligament appears to be effective in treating both chronic and acute acromioclavicular joint dislocations.

  9. [Arthroscopic therapy of ankle joint impingement syndrome after operation of ankle joint fracture dislocation].

    Science.gov (United States)

    Feng, Zhibin; Mi, Kun; Wei, Renzhi; Liu, Wu; Wang, Bin

    2011-07-01

    To study the operative procedure and the effectiveness of arthroscopic therapy for ankle joint impingement syndrome after operation of ankle joint fracture dislocation. Between March 2008 and April 2010, 38 patients with ankle joint impingement syndrome after operation of ankle joint fracture dislocation were treated. Among them, there were 28 males and 10 females with an average age of 28 years (range, 18 to 42 years). The time from internal fixation to admission was 12-16 months (mean, 13.8 months). There were pressing pain in anterolateral and anterior ankle. The dorsal extension ranged from -20 to -5 degrees (mean, -10.6 degrees), and the palmar flexion was 30-40 degrees (mean, 35.5 degrees). The total score was 48.32 +/- 9.24 and the pain score was 7.26 +/- 1.22 before operation according to American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score system. The X-ray films showed osteophyte formation in anterior tibia and talus; MRI showed cartilage injury in 22 cases. Arthroscopic intervention included removing osteophytes, debriding fabric scars and synovial membrane tissues, and removing osteochondral fragments. Arthroscopic microfracture technique was used in 22 patients with cartilage injury. All incisions healed primarily. Thirty-eight cases were followed up 10-26 months (mean, 16 months). At last follow-up, 26 patients had normal range of motion (ROM); the dorsal extension was 15-25 degrees (mean, 19.6 degrees) and the palmar flexion was 35-45 degrees (mean, 40.7 degrees). Eight patients had mild limited ROM; the dorsal extension was 5-15 degrees (mean, 7.2 degrees) and the palmar flexion was 35-45 degrees (mean, 39.5 degrees). Four patients had mild limited ROM and pain in posterior portion of the ankle after a long walking (3-4 hours); the dorsal extension was 0-5 degrees (mean, 2.6 degrees) and the palmar flexion was 35-40 degrees (mean, 37.5 degrees). The total score was 89.45 +/- 9.55 and the pain score was 1.42 +/- 1.26 after

  10. Interobserver and intraobserver reliability of radiographic classification of acromioclavicular joint dislocations.

    Science.gov (United States)

    Ringenberg, Jonathan D; Foughty, Zachary; Hall, Adam D; Aldridge, J Mack; Wilson, Joseph B; Kuremsky, Marshall A

    2018-03-01

    The classification and treatment of acromioclavicular (AC) joint dislocations remain controversial. The purpose of this study was to determine the interobserver and intraobserver reliability of the Rockwood classification system. We hypothesized poor interobserver and intraobserver reliability, limiting the role of the Rockwood classification system in determining severity of AC joint dislocations and accurately guiding treatment decisions. We identified 200 patients with AC joint injuries using the International Classification of Diseases, Ninth Revision code 831.04. Fifty patients met inclusion criteria. Deidentified radiographs were compiled and presented to 6 fellowship-trained upper extremity orthopedic surgeons. The surgeons classified each patient into 1 of the 6 classification types described by Rockwood. A second review was performed several months later by 2 surgeons. A κ value was calculated to determine the interobserver and intraobserver reliability. The interobserver and intraobserver κ values were fair (κ = 0.278) and moderate (κ = 0.468), respectively. Interobserver results showed that 4 of the 50 radiographic images had a unanimous classification. Intraobserver results for the 2 surgeons showed that 18 of the 50 images were rated the same on second review by the first surgeon and 38 of the 50 images were rated the same on second review by the second surgeon. We found that the Rockwood classification system has limited interobserver and intraobserver reliability. We believe that unreliable classification may account for some of the inconsistent treatment outcomes among patients with similarly classified injuries. We suggest that a better classification system is needed to use radiographic imaging for diagnosis and treatment of AC joint dislocations. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  11. Botulinum Neurotoxin Injection for the Treatment of Recurrent Temporomandibular Joint Dislocation with and without Neurogenic Muscular Hyperactivity

    Directory of Open Access Journals (Sweden)

    Kazuya Yoshida

    2018-04-01

    Full Text Available The aim of this study was to compare treatment outcomes following intramuscular injection of botulinum neurotoxin (BoNT in patients with recurrent temporomandibular joint dislocation, with and without muscle hyperactivity due to neurological diseases. Thirty-two patients (19 women and 13 men, mean age: 62.3 years with recurrent temporomandibular joint dislocation were divided into two groups: neurogenic (8 women and 12 men and habitual (11 women and 1 man. The neurogenic group included patients having neurological disorders, such as Parkinson’s disease or oromandibular dystonia, that are accompanied by muscle hyperactivity. BoNT was administered via intraoral injection to the inferior head of the lateral pterygoid muscle. In total, BoNT injection was administered 102 times (mean 3.2 times/patient. The mean follow-up duration was 29.5 months. The neurogenic group was significantly (p < 0.001 younger (47.3 years than the habitual group (84.8 years and required significantly (p < 0.01 more injections (4.1 versus 1.7 times to achieve a positive outcome. No significant immediate or delayed complications occurred. Thus, intramuscular injection of BoNT into the lateral pterygoid muscle is an effective and safe treatment for habitual temporomandibular joint dislocation. More injections are required in cases of neurogenic temporomandibular joint dislocation than in those of habitual dislocation without muscle hyperactivity.

  12. Controversies relating to the management of acromioclavicular joint dislocations.

    Science.gov (United States)

    Modi, C S; Beazley, J; Zywiel, M G; Lawrence, T M; Veillette, C J H

    2013-12-01

    The aim of this review is to address controversies in the management of dislocations of the acromioclavicular joint. Current evidence suggests that operative rather than non-operative treatment of Rockwood grade III dislocations results in better cosmetic and radiological results, similar functional outcomes and longer time off work. Early surgery results in better functional and radiological outcomes with a reduced risk of infection and loss of reduction compared with delayed surgery. Surgical options include acromioclavicular fixation, coracoclavicular fixation and coracoclavicular ligament reconstruction. Although non-controlled studies report promising results for arthroscopic coracoclavicular fixation, there are no comparative studies with open techniques to draw conclusions about the best surgical approach. Non-rigid coracoclavicular fixation with tendon graft or synthetic materials, or rigid acromioclavicular fixation with a hook plate, is preferable to fixation with coracoclavicular screws owing to significant risks of loosening and breakage. The evidence, although limited, also suggests that anatomical ligament reconstruction with autograft or certain synthetic grafts may have better outcomes than non-anatomical transfer of the coracoacromial ligament. It has been suggested that this is due to better restoration horizontal and vertical stability of the joint. Despite the large number of recently published studies, there remains a lack of high-quality evidence, making it difficult to draw firm conclusions regarding these controversial issues.

  13. Acromioclavicular Joint Dislocation with Ipsilateral Mid Third Clavicle, Mid Shaft Humerus and Coracoid Process Fracture - A Case Report.

    Science.gov (United States)

    Sharma, Naveen; Mandloi, Avinash; Agrawal, Ashish; Singh, Shailendra

    2016-01-01

    The clavicle, humerus and acromioclavicular (AC) joint separately are very commonly involved in traumatic injuries around the shoulder. Acromioclavicular joint dislocation with distal clavicle fracture is a well recognized entity in clinical practice. AC joint dislocation with mid shaft clavicle fracture is uncommon and only few cases have been reported in literature. However, to the best of our knowledge, this is the first case report to describe an acromioclavicular dislocation with ipsilateral mid shaft clavicle, mid shaft humerus and coracoid process fracture. Fractures of the humerus and clavicle along with the acromioclavicular joint dislocation were fixed at the same setting. A 65-year-old male met with a high velocity road traffic accident. Plain radiographs showed displaced mid third clavicle fracture with acromioclavicular joint dislocation with mid shaft humerus fracture. Surgical fixation was planned for humerus with interlocking nail, clavicle with locking plate and acromioclavicular joint with reconstruction of coracoclavicular ligaments. Intraoperatively, coracoid process was found to have a comminuted fracture. The operative plan had to be changed on table as coracoclavicular fixation was not possible. So acromioclavicular joint fixation was done using tension band wiring and the coracoclavicular ligament was repaired using a 2-0 ethibond. The comminuted coracoid fracture was managed conservatively. K wires were removed at 6 weeks. Early mobilization was started. In acromioclavicular joint injuries, clavicle must be evaluated for any injury. Although it is more commonly associated with distal clavicle fractures, it can be associated with middle third clavicle fractures. As plain radiographs, AP view are most of the times insufficient for viewing integrity of coracoid process, either special views like Stryker notch or CT scan may help in diagnosing such concealed injuries. When associated with fractures of the humerus and clavicle, anatomical

  14. Prosthesis of the wrist-joint

    Energy Technology Data Exchange (ETDEWEB)

    Feldmeier, C.

    1983-02-25

    Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated.

  15. Psychogenic Equinovarus Caused by Dislocation of the Chopart Joint Complex

    Directory of Open Access Journals (Sweden)

    Ichiro Tonogai

    2018-01-01

    Full Text Available Patients with conversion disorder (CD present with weakness or unexplained movement disorder that may evolve from inciting psychological events, but presentation with rigid deformity is rare. Only one case of CD presenting as foot deformity with atraumatic rigid psychogenic equinovarus has been reported previously. Here we describe a rare case of psychogenic equinovarus in a physically healthy 10-year-old boy. He had noticed left equinovarus deformity upon waking abruptly but had no history of preceding trauma and no relevant medical history. Computed tomography (CT images revealed dislocation of the left Chopart joint complex, but clinical examination did not suggest an organic neurologic disorder. On further history taking, he reported that he was under psychological stress because of being required to play baseball against his will. When he was given permission to withdraw from this stressful situation, the equinovarus improved without the need for surgical invention. This report highlights the importance of early and accurate diagnosis of psychogenic equinovarus, so that unnecessary surgery can be avoided. This is the first report of psychogenic equinovarus caused by dislocation of the Chopart joint complex that was confirmed with CT.

  16. Prosthesis of the wrist-joint

    International Nuclear Information System (INIS)

    Feldmeier, C.

    1983-01-01

    Function of the hand-joint and the well-being of patients can be severely affected by arthrosis of the wrist-joint. Therapeutically, arthrodesis usually results in a painfree status of stiffness. A painless and well functioning joint can be achieved by alloplastic joint replacement or resurfacing. The possibilities and clinical results in cases of arthrosis of the carpo-metacarpal joint of the thumb, pseudarthrosis of the scaphoid, aseptic necrosis of the Lunate and severe arthrosis of the radio-carpal joint are demonstrated. (orig.) [de

  17. [Case control study of fractures-dislocations of ankle joint with conservative and operative treatment].

    Science.gov (United States)

    Zhang, Song-Tu; Lin, Yi-Rong; Chen, Lian-Yuan

    2010-10-01

    To compare the clinical efficacy of grade III, IV supination-eversion fractures-dislocations of ankle joint between manipulative treatment and operative treatment. From September 2007 to December 2008, the clinical data of 60 patients with grade III, IV supination-eversion fractures-dislocations of ankle joint were retrospectively analyzed. There were 32 males and 28 females, ranging in age from 18 to 70 years with an average age of 38.17 years. All patients were respectively treated with manipulative treatment (conservative group, 30 cases) and operative treatment (operative group, 30 cases). The joint function was compared with Mazur standard; the reduction and shifting of fractures were observed with X-ray; the hospitalization day and the therapeutic cost were compared between two groups. All patients were followed up with an average of 15.27 months (ranged, 6 to 25 months). In conservative group, 16 cases got excellent result in joint function, 10 good, 3 fair, 1 poor; in operative group, 20 cases got excellent result, 8 good, 2 fair, 0 poor. In conservative group in the X-ray showed 25 cases obtained excellent and good reduction, 4 fair, 1 poor; and in operative group in the X-ray showed 28 cases obtained excellent and good reduction, 2 fair, 0 poor. There was no significant difference at the joint function and X-ray film after treatment between two groups (P > 0.05). The hospital day was respectively (7.87 +/- 3.34), (17.37 +/- 4.64) d in conservative group and operative group; and the therapeutic cost was respectively (2 506.67 +/- 649.10), (11 473.33 +/- 1 564.90) yuan. There was significant difference at hospital day and therapeutic cost between two groups (P fractures and dislocations of ankle joint. However, conservative treatment has advantage of high safety factor, low therapeutic cost, can reduce medical costs for patients.

  18. Closed reduction with CT-guided screw fixation for unstable sacroiliac joint fracture-dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Baskin, Kevin M.; Cahill, Ann Marie; Kaye, Robin D. [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Born, Christopher T. [Temple University Hospital/Temple Children' s Hospital, Temple Sports Medicine, Marlton, NJ (United States); Grudziak, Jan S. [Children' s Hospital of Pittsburgh, Department of Orthopedic Surgery, Pittsburgh, PA (United States); Towbin, Richard B.

    2004-12-01

    Unstable posterior pelvic ring fractures and dislocations are uncommon but potentially life-threatening injuries in children. Early definitive management reduces risk of immediate complications as well as chronic pain and gait dysfunction. Conventional operative therapy carries substantial risk of extensive blood loss and iatrogenic neurological and vascular injury. Minimally invasive image-guided intervention may further reduce immediate risk and improve long-term outcome. To describe CT-guided closed reduction and internal fixation (CRIF) and review outcomes of unstable fracture-dislocation of the sacroiliac (SI) joint in children. Between 2000 and 2003, three children (two girls, one boy) age 8-14 years were referred to interventional radiology for treatment of unstable SI joint fracture-dislocation not adequately treated with anterior external fixation alone. The three affected SI joints (two left, one right) were treated in a combined approach by pediatric interventional radiologists and orthopedic surgeons, using a percutaneous approach under CT guidance. Over a threaded guiding pin, 7.3 mm cannulated screws were used to achieve stable reduction of the affected SI joints. One screw was removed after slight (2 mm) migration. No neurovascular or other complications occurred. All patients had satisfactory healing with near-anatomic reduction, although recovery of the youngest was delayed by associated spinal injury. Compared to open surgical alternatives, CRIF under CT guidance reduces operating time, decreases blood loss, and allows early definitive fixation and immediate non-weight-bearing mobilization with a low rate of complication for unstable posterior pelvic ring fractures. In addition, CT-guided placement of the guide pin may allow safer screw positioning and may minimize the total number of screws needed to achieve pelvic stability. (orig.)

  19. Closed reduction with CT-guided screw fixation for unstable sacroiliac joint fracture-dislocation

    International Nuclear Information System (INIS)

    Baskin, Kevin M.; Cahill, Ann Marie; Kaye, Robin D.; Born, Christopher T.; Grudziak, Jan S.; Towbin, Richard B.

    2004-01-01

    Unstable posterior pelvic ring fractures and dislocations are uncommon but potentially life-threatening injuries in children. Early definitive management reduces risk of immediate complications as well as chronic pain and gait dysfunction. Conventional operative therapy carries substantial risk of extensive blood loss and iatrogenic neurological and vascular injury. Minimally invasive image-guided intervention may further reduce immediate risk and improve long-term outcome. To describe CT-guided closed reduction and internal fixation (CRIF) and review outcomes of unstable fracture-dislocation of the sacroiliac (SI) joint in children. Between 2000 and 2003, three children (two girls, one boy) age 8-14 years were referred to interventional radiology for treatment of unstable SI joint fracture-dislocation not adequately treated with anterior external fixation alone. The three affected SI joints (two left, one right) were treated in a combined approach by pediatric interventional radiologists and orthopedic surgeons, using a percutaneous approach under CT guidance. Over a threaded guiding pin, 7.3 mm cannulated screws were used to achieve stable reduction of the affected SI joints. One screw was removed after slight (2 mm) migration. No neurovascular or other complications occurred. All patients had satisfactory healing with near-anatomic reduction, although recovery of the youngest was delayed by associated spinal injury. Compared to open surgical alternatives, CRIF under CT guidance reduces operating time, decreases blood loss, and allows early definitive fixation and immediate non-weight-bearing mobilization with a low rate of complication for unstable posterior pelvic ring fractures. In addition, CT-guided placement of the guide pin may allow safer screw positioning and may minimize the total number of screws needed to achieve pelvic stability. (orig.)

  20. The patellofemoral joint: from dysplasia to dislocation

    Science.gov (United States)

    Zaffagnini, Stefano; Grassi, Alberto; Zocco, Gianluca; Rosa, Michele Attilo; Signorelli, Cecilia; Muccioli, Giulio Maria Marcheggiani

    2017-01-01

    Patellofemoral dysplasia is a major predisposing factor for instability of the patellofemoral joint. However, there is no consensus as to whether patellofemoral dysplasia is genetic in origin, caused by imbalanced forces producing maltracking and remodelling of the trochlea during infancy and growth, or due to other unknown and unexplored factors. The biomechanical effects of patellofemoral dysplasia on patellar stability and on surgical procedures have not been fully investigated. Also, different anatomical and demographic risk factors have been suggested, in an attempt to identify the recurrent dislocators. Therefore, a comprehensive evaluation of all the radiographic, MRI and CT parameters can help the clinician to assess patients with primary and recurrent patellar dislocation and guide management. Patellofemoral dysplasia still represents an extremely challenging condition to manage. Its controversial aetiology and its complex biomechanical behaviour continue to pose more questions than answers to the research community, which reflects the lack of universally accepted guidelines for the correct treatment. However, due to the complexity of this condition, an extremely personalised approach should be reserved for each patient, in considering and addressing the anatomical abnormalities responsible for the symptoms. Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160081. Originally published online at www.efortopenreviews.org PMID:28630757

  1. The field size matters: low dose external beam radiotherapy for thumb carpometacarpal osteoarthritis : Importance of field size.

    Science.gov (United States)

    Kaltenborn, Alexander; Bulling, Elke; Nitsche, Mirko; Carl, Ulrich Martin; Hermann, Robert Michael

    2016-08-01

    The purpose of this work was to evaluate the efficacy of low-dose radiotherapy (RT) for thumb carpometacarpal osteoarthritis (rhizarthrosis). The responses of 84 patients (n = 101 joints) were analyzed 3 months after therapy (n = 65) and at 12 months (n = 27). Patients were treated with 6 fractions of 1 Gy, two times a week, with a linear accelerator. At the end of therapy, about 70 % of patients reported a response (partial remission or complete remission), 3 months later about 60 %, and 1 year after treatment 70 %. In univariate regression analysis, higher patient age and field size greater than 6 × 4 cm were associated with response to treatment, while initial increase of pain under treatment was predictive for treatment failure. Duration of RT series (more than 18 days), gender, time of symptoms before RT, stress pain or rest pain, or prior ortheses use, injections, or surgery of the joint were not associated with treatment efficacy. In multivariate regression analysis, only field size and initial pain increase were highly correlated with treatment outcome. In conclusion, RT represents a useful treatment option for patients suffering from carpometacarpal osteoarthritis. In contrast to other benign indications, a larger field size (>6 × 4 cm) seems to be more effective than smaller fields and should be evaluated in further prospective studies.

  2. A closed dorsolateral dislocation of PIP joint of the fourth toe-a case report and review of literature

    Directory of Open Access Journals (Sweden)

    Prof. Giris Kumar Singh

    2009-01-01

    Full Text Available Interphalangeal (IP joint dislocations of the toes are uncommon lesions. We present here a case of closed dorsolateral dislocation of proximal interphalangeal (PIP joint of the fourth toe. Closed reduction and buddy strapping have been done with middle toe for two weeks under digital block. There was painless full range of movement after 2 weeks. We propose that attempt of closed reduction must be given adequately under anesthesia before proceeding for open reduction.

  3. Biomechanical analysis of acromioclavicular joint dislocation treated with clavicle hook plates in different lengths.

    Science.gov (United States)

    Shih, Cheng-Min; Huang, Kui-Chou; Pan, Chien-Chou; Lee, Cheng-Hung; Su, Kuo-Chih

    2015-11-01

    Clavicle hook plates are frequently used in clinical orthopaedics to treat acromioclavicular joint dislocation. However, patients often exhibit acromion osteolysis and per-implant fracture after undergoing hook plate fixation. With the intent of avoiding future complications or fixation failure after clavicle hook plate fixation, we used finite element analysis (FEA) to investigate the biomechanics of clavicle hook plates of different materials and sizes when used in treating acromioclavicular joint dislocation. Using finite element analysis, this study constructed a model comprising four parts: clavicle, acromion, clavicle hook plate and screws, and used the model to simulate implanting different types of clavicle hook plates in patients with acromioclavicular joint dislocation. Then, the biomechanics of stainless steel and titanium alloy clavicle hook plates containing either six or eight screw holes were investigated. The results indicated that using a longer clavicle hook plate decreased the stress value in the clavicle, and mitigated the force that clavicle hook plates exert on the acromion. Using a clavicle hook plate material characterized by a smaller Young's modulus caused a slight increase in the stress on the clavicle. However, the external force the material imposed on the acromion was less than the force exerted on the clavicle. The findings of this study can serve as a reference to help orthopaedic surgeons select clavicle hook plates.

  4. [Repair and reconstruction for severe fracture and dislocation of ankle joint].

    Science.gov (United States)

    Yin, Qingwei; Jiang, Yi; Xiao, Lianping; Li, Xiaodong; Fu, Jiaxin; Tian, Yonggang; Han, Liqiang; Liu, Zhi

    2008-06-01

    To summarize the technique and effect of the therapy for severe fracture and dislocation of ankle joint by operation. From March 2003 to February 2006, 76 cases were treated with primary open restoration and internal fixation for dislocated ankle joint fracture, with 47 males and 29 females, with the average age of 36.4 years (ranging from 18 years to 65 years). According to AO criterion, these fresh fractures were classified into 13 cases for type C3-1, 45 cases for type C3-2 and 18 cases for type C3-3. Based on the Gustilo-Anderson standard, 23 open fractures were classified into 17 cases for type II and 6 cases for type III A. The operation was delayed from 1 hours to 24 hours after the injury. All incisions healed at the first stage except 4 cases which delayed union because of simple infection by revision with ointment. A total of 72 cases were followed up, with the average time of 18.5 months (from 12 months to 35 months). The time of bone union was from 12 weeks to 24 weeks. The screws of fixation for lower tibia-fibula joint were found to be ruptured in 2 cases when further consultation was performed in the 16th and 20th week after the operation, respectively, and were broken within 1 year after the operation. These screws were taken out 12 weeks postoperative in 28 cases, while the whole internal fixations of the rest cases were taken out 1 year after the operation. The postoperative function of malleolus extended from 21.7 degrees to 26.8 degrees and flection from 38.5 degrees to 44.7 degrees. Assessed by the American Orthopaedic Foot and Ankle Society Clinical Rating Scales, 23 cases were excellent, 36 good, 13 fair, and the choiceness rate reached 81.94%. These procedures, together with reduction by twist after hospital, open and internal fixation in time, and parenchyma managed with internal fixation, are important to attain satisfactory effect for the treatment of severe fracture and dislocation of ankle joint.

  5. Treatment of peroneal tendon dislocation and coexisting medial and lateral ligamentous laxity in the ankle joint.

    Science.gov (United States)

    Ziai, Pejman; Sabeti-Aschraf, Manuel; Fehske, Kai; Dlaska, Constantin E; Funovics, Philipp; Wenzel, Florian; Graf, Alexandra; Buchhorn, Tomas

    2011-06-01

    Acute dislocation of the peroneal tendon is caused by massive combined flexion-torsion trauma supported by preexisting ligamentous laxity of the ankle joint. This study aimed to investigate the clinical outcome of combined treatment of peroneal tendon dislocation and lateral and medial ligamentous laxity. Between 2005 and 2007, forty-two patients with peroneal tendon dislocation and coexisting ligamentous laxity were treated. The superior extensor retinaculum was reconstructed using anchor technique and periosteal flap repair, whereas the preexisting ligamentous laxity with regard to the extensor inferior retinaculum was addressed using anchor reconstruction. All patients underwent arthroscopy prior to surgery. Thirty-eight of a total of 42 patients (aged 17-31) completed the 24-month follow-up. Clinical and arthroscopic examination was accomplished consistently by always the same two surgeons. Postoperative follow-up comprised clinical evaluation after 3, 6, 12 and 24 months. Clinical results showed a significant (Pankle joint following arthroscopy results in good clinical outcome and high patient satisfaction. Case series, Level IV.

  6. Condylar Joint Fusion and Stabilization (by Screws and Plates) in Nontraumatic Atlanto-Occipital Dislocation: Technical Report of 2 Cases.

    Science.gov (United States)

    Chowdhury, Forhad H; Haque, Mohammod Raziul; Alam, Sarwar Murshed; Khaled Chowdhury, S M Noman; Khan, Shamsul Islam; Goel, Atul

    2017-11-01

    Nontraumatic spontaneous atlanto-occipital dislocation (AOD) is rare. In this report, we discuss the technical steps of condylar joint fusion and stabilization (by screws and plates) in nontraumatic AOD. To the best of our knowledge, it is the first report of such techniques. A young girl and a young man with progressive quadriparesis due to nontraumatic spontaneous atlanto-occipital dislocation were managed by microsurgical reduction, fusion, and stabilization of the joint by occipital condylar and C1 lateral mass screw and plate fixation after mobilization of vertebral artery. In both cases, condylar joints fixation and fusion were done successfully. Condylar joint stabilization and fusion may be a good or alternative option for AOD. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Modified technique of the treatment for proximal tibiofibular joint dislocation

    Directory of Open Access Journals (Sweden)

    Gvozdenović Nemanja

    2017-01-01

    Full Text Available Introduction. Dislocation of the proximal tibiofibular joint (PTFJ is a rare injury. The diagnosis requires an accurate history of the mechanism and symptoms of the injury, and adequate clinical and radiographic evaluation of both knees. In the literature there is no larger series, only several cases of PTFJ dislocation treated by different methods have been published so far. The aim of the study was to present a modified technique for the treatment of the unstable PTFJ that results in faster recovery of the patient. Case report. A 24-year-old football player was injured at the beginning of training; when tackling the ball he felt a sharp pain in his right knee. He was immediately brought to the Emergency Center of Vojvodina and diagnosed with anterolateral dislocation of the PTFJ. Close reduction in general anesthesia was tried but we failed and then open reduction and internal fixation (ORIF were performed with a single three cortical screw. We preferred not to immobilise the knee after the procedure and immediately employed passive and active exercises in the knee, without bearing weight to the injured leg. After 6 weeks we removed the screw and gave full weight support to the leg and continued physical treatment. Conclusion. In case of acute PTFJ dislocation, the first method of choice is closed reduction in sedation or general anesthesia. If closed reduction fails, ORIF must be performed. ORIF without immobilization and early start of physical therapy lead to the rapid return to sports activities

  8. Total carpometacarpal joint dislocation combined with trapezium fracture, trapezoid dislocation and hamate fracture

    DEFF Research Database (Denmark)

    Gvozdenovic, R; Vadstrup, Lars Soelberg

    2015-01-01

    and resulted from rupture of both transverse and longitudinal carpal columns. According to the Garcia-Elias classification of axial carpal disruptions, this particular injury mechanism was a combined axial-radial-ulnar type injury. These injuries are extremely rare and are only sporadically described...

  9. Arthroscopic procedures and therapeutic results of anatomical reconstruction of the coracoclavicular ligaments for acromioclavicular Joint dislocation.

    Science.gov (United States)

    Takase, K; Yamamoto, K

    2016-09-01

    Surgical treatment is recommended for type 5 acromioclavicular joint dislocation on Rockwood's classification. We believe that anatomic repair of the coracoclavicular ligaments best restores the function of the acromioclavicular joint. We attempted to correctly reconstruct the anatomy of the coracoclavicular ligaments under arthroscopy, and describe the minimally invasive arthroscopic procedure. There were 22 patients; mean age at surgery, 38.1 years. Mean time to surgery was 13.2 days. Mean follow-up was 3 years 2 months. The palmaris longus tendon was excised from the ipsilateral side to replace the conoid ligament, while artificial ligament was used for reconstructing the trapezoid ligament. Both ligament reconstructions were performed arthroscopically. No temporary fixation of the acromioclavicular joint was performed. On postoperative radiographic evaluation, 4 patients showed subluxation and 2 showed dislocation of the acromioclavicular joint; the other 16 patients had maintained reduction at the final consultation. MR images 1year after surgery clearly revealed the reconstructed ligaments in 19 patients. Only 1 patient showed osteoarthritis of the acromioclavicular joint. Although it requires resection of the ipsilateral palmaris longus for grafting, we believe that anatomic reconstruction of both coracoclavicular ligaments best restores the function of the acromioclavicular joint. 4. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. [Complications of treatment of acromioclavicular joint dislocation and unstable distal clavicular fracture with clavicular hook plate].

    Science.gov (United States)

    Zhu, Yi-Yong; Cui, Heng-Yan; Jiang, Pan-Qiang; Wang, Jian-Liang

    2013-11-01

    To investigate the causes and prevention of the complications about treatment of acromioclavicular joint dislocation (Tossy III) and unstable distal clavicular fracture (Neer II) with clavicular hook plate. From January 2001 to December 2011, 246 patients with acromioclavicular joint dislocation (Tossy III) and 222 patients with unstable distal clavicular fracture (Neer II) were treated with acromioclvicular hook plate fixation,including 348 males and 120 females with an average age of 45.4 years old ranging from 21 to 80 years old. The mean time from injury to operation was 30.8 hours (ranged from 1 h to 15 d). All patients had normal shoulder function before injury. According to Karlsson evaluation standard, the cases with excellent and good function of the shoulder joint were regarded as the normal group, and the cases with poor function of shoulder joint as the abnormal group. The comparison of the range of forward flexion,backward stretch, adduction, abduction and elevation of shoulder joints between two groups was performed. The data of impingement, subacromial osteolysis, acromioclavicular arthritis, clavicular stress fracture, downward acromioclavicular joint subluxation, hook cut-out and hook break were summarized. All patients were followed up from 8 to 48 months with an average of 12.5 months. The results were excellent in 308 cases,good in 76,and poor in 84 according to Karlsson evaluation. The excellent and good rate was 82.1%. The difference of the range of forward flexion, backward stretch, adduction, abduction and elevation of shoulder joints between two groups had a statistically significant difference (P acromioclavicular arthritis or painful shoulder caused by delayed dirigation,7 (1.50%) with clavicular stress fracture or interal plate upward, 6 (1.28%) with downward acromioclavicular joint subluxation, 5 (1.07%) with hook cut -out and 3 (0.64%) in hook break. The clavicular hook plate is useful for the treatment of acromioclavicular joint

  11. Palliative surgery for acetabular metastasis with pathological central dislocation of the hip joint after radiation therapy. A case report

    International Nuclear Information System (INIS)

    Hoshi, Manabu; Takada, Jun; Oebisu, Naoto; Nakamura, Hiroaki; Taguchi, Susumu; Takami, Masatsugu

    2012-01-01

    Orthopedic surgery for bone metastases is mainly a palliative treatment. Pathological central dislocation of the hip joint secondary to osteonecrosis of acetabular metastasis after radiation therapy brings severe suffering to cancer patients. We performed minimally invasive palliative surgery for an elderly woman, and excellent pain relief was achieved. An 80-year-old female suffering from right hip pain was referred to our hospital. She had undergone surgery for lung cancer 5 years previously and her right acetabulum was subsequently affected by metastasis. With the aim of controlling the metastasis, radiation therapy was performed. Two years later, pathological central dislocation of the hip joint occurred with sudden onset of severe pain, and she was unable to maintain a sitting position and became bedridden. After she was referred to our hospital, we created an intentional pseudarthrosis in the femoral neck for palliation. After the surgery, excellent pain relief and remarkably improved mobility were achieved during her limited remaining lifetime. In this report, we introduce a novel method of producing a pseudarthrosis in the femoral neck for pathological dislocation. This procedure is a minimally invasive treatment and an alternative option for palliative surgery for pathological dislocation of the hip joint due to osteonecrosis after radiation therapy. (author)

  12. [Operative treatment of sacroiliac joint fracture and dislocation in Tile C pelvic fracture with Colorado 2 system].

    Science.gov (United States)

    Liu, Shuping; Zhou, Qing; Liu, Yuehong; Chen, Xi; Zhou, Yu; Zhang, Desheng; Fang, Zhi; Xu, Wei

    2011-12-01

    To explore the effectiveness of Colorado 2 system in the stability reconstruction of sacroiliac joint fracture and dislocation in Tile C pelvic fracture. Between February 2009 and January 2011, 8 cases of Tile C pelvic fracture were treated with Colorado 2 system. There were 3 males and 5 females with an average age of 34.4 years (range, 22-52 years). Fractures were caused by traffic accident in 3 cases, by falling from height in 3 cases, and by crash of heavy object in 2 cases. According to Tile classification, 5 cases were classified as C1-2, 2 cases as C1-3, and 1 case as C2. The time between injury and operation was 5-10 days (mean, 7 days). After skeletal traction reduction, Colorado 2 system was used to fix sacroiliac joint, and reconstruction plate or external fixation was selectively adopted. The postoperative X-ray films showed that the reduction of vertical and rotatory dislocation was satisfactory, posterior pelvic ring achieved effective stability. All the incisions healed by first intention, and no blood vessel or nerve injury occurred. Eight patients were followed up 6-24 months (mean, 12 months). No loosening or breakage of internal fixation was observed and no re-dislocation of sacroiliac joint occurred. The bone healing time was 6-12 months (mean, 9 months). According to Majeed's functional criterion, the results were excellent in 5 cases, good in 2 cases, and fair in 1 case at last follow-up. Colorado 2 system could provide immediate stability of pelvic posterior ring and good maintenance of reduction effect, which is an effective method in the therapy of sacroiliac joint fracture and dislocation in Tile C pelvic fracture.

  13. Coracoid Process Avulsion Fracture at the Coracoclavicular Ligament Attachment Site in an Osteoporotic Patient with Acromioclavicular Joint Dislocation

    Directory of Open Access Journals (Sweden)

    Yoshihiro Onada

    2016-01-01

    Full Text Available Coracoid fractures are uncommon, mostly occur at the base or neck of the coracoid process (CP, and typically present with ipsilateral acromioclavicular joint (ACJ dislocation. However, CP avulsion fractures at the coracoclavicular ligament (CCL attachment with ACJ dislocation have not been previously reported. A 59-year-old woman receiving glucocorticoid treatment fell from bed and complained of pain in her shoulder. Radiographs revealed an ACJ dislocation with a distal clavicle fracture. Three-dimensional computed tomography (3D-CT reconstruction showed a small bone fragment at the medial apex of the CP. She was treated conservatively and achieved a satisfactory outcome. CP avulsion fractures at the CCL attachment can occur in osteoporotic patients with ACJ dislocations. Three-dimensional computed tomography is useful for identifying this fracture type. CP avulsion fractures should be suspected in patients with ACJ dislocations and risk factors for osteoporosis or osteopenia.

  14. Temporomandibular joint dislocation in an epileptic and mentally ...

    African Journals Online (AJOL)

    Theories regarding the pathogenesis of TMJ dislocation propose laxity of TMJ ligaments or capsule, excessive activity of the lateral pterygoid muscle (LPM)and erosion of the eminence'. TMJ dislocation can occur in an anterior, posterior, lateral and superior direction'. Clinical presentation of dislocated TMJ includes inability ...

  15. Clinical Effect of Acute Complete Acromioclavicular Joint Dislocation Treated with Micro-Movable and Anatomical Acromioclavicular Plate

    Science.gov (United States)

    Liu, Qingjun; Miao, Jianyun; Lin, Bin; Guo, Zhimin

    2012-01-01

    Objectives: We evaluated the long-term clinical results of acute complete acromioclavicular dislocations treated with micro-movable and anatomical acromioclavicular plate. Methods: Open reduction and internal fixation was performed using the MAAP in 16 patients (10 males, 6 females; mean age 36 years; range16 to 63 years) with acute complete acromioclavicular joint dislocation. Radiographic evaluations were routinely conducted every 3 weeks until 3 months postoperatively. The MAAP were removed under local anesthesia after 3 months postoperatively. We evaluated the functional results by using the constant scoring system and radiological results in the last follow-up time. The mean follow up was 26 months (range 16 to 38 months). Results: The mean Constant score was 94 (range, 78 to 100). The results were excellent in 12 patients (75.0%), good in 3 patients (18.8%) and satisfactory in 1patient (6.2%). Three patients with scores of 80 to 90 had mild pain during activity, but have not affected the shoulder range of motion. One patient has both some pain and limited range of motion of shoulder joint. All patients but one have returned to their preoperative work without any limitations. Compared to the contralateral side, radiography showed anatomical reposition in the vertical plane in 14 cases, slight loss of reduction in 2 older patients. Conclusion: We recommend the MAAP fixation for surgical treatment of acute complete acromioclavicular joint dislocation as it could provide satisfactory shoulder functions and clinical results, with lower complication rate. However, it is necessary to continue to observe the clinical effects of this fixation technique. PMID:23091410

  16. BILATERAL PATHOLOGICAL HIP DISLOCATION IN CHILDREN

    Directory of Open Access Journals (Sweden)

    Yuriy E. Garkavenko

    2017-03-01

    Full Text Available Introduction. Pathological dislocation of the hip is one of the most severe complications of acute hematogenous osteomyelitis. The program of treatment for children with pathological hip dislocation is complex, but it has been sufficiently developed and implemented very successfully. At the same time, the available literature provides no cases of treating children with bilateral pathological hip dislocations after hematogenous osteomyelitis. There is no information on the incidence of such cases or in regards to remote functional results. Materials and methods. The results of the treatment of 18 children with bilateral pathological dislocation of the hip after hematogenous osteomyelitis are presented, which constituted 23.1% of the total number of patients (78 who underwent surgery in 2000–2016 for the diagnosis of pathological hip dislocation. Both hip joints were surgically operated on in 12 patients, while one hip joint was operated on in 6 patients. To assess the anatomical and functional state of hip joints, the clinical and roentgenological diagnostic techniques were used. Results and discussion. To stabilize and restore the function of the hip joints, 18 children underwent 30 surgical interventions: simple open hip reduction (19 and open hip reduction with hip arthroplasty with one (6 or two (5 demineralized osteochondral allogeneic grafts. The decision regarding the possibility of performing surgical intervention on the second hip joint was made only after a child's check-up examination was complete and after positive information about the anatomical and functional state of the operated hip joint was obtained. According to these criteria, 14 (77.8% children underwent surgical treatment of the second hip joint 1–1.5 years after the course of conservative measures to restore the range of motion in the previously operated hip joint. Over a period of 1–12 years, 17 patients were examined, 10 of which underwent an operation on both

  17. Posterior dislocation of the sternoclavicular joint leading to mediastinal compression.

    Science.gov (United States)

    Jougon, J B; Lepront, D J; Dromer, C E

    1996-02-01

    Dislocations of the sternoclavicular joint are uncommon, and the posterior variety have a potential for considerable morbidity. We report a case with compression of the vital structures within the superior mediastinum. It was a rugby player getting run over by the scrum. The mechanism was an indirect force exerted forward and laterally against the shoulder. The patient complained of pain and dysphagia. A systolic right cervical murmur was heard. Angiography was normal and esophagography showed extrinsic esophageal compression. Surgical reduction was performed because there was a slight pneumomediastinum on the computed tomography. This case report demonstrates the mechanism, complications, and treatment of such a lesion.

  18. Locomotor adaptations reflected in the wrist joints of early tertiary primates (adapiformes).

    Science.gov (United States)

    Hamrick, M W

    1996-08-01

    The positional behaviors inferred for early Tertiary adapiform primates have been the subject of considerable debate. Adapiform wrist morphology is analyzed here within the context of extant morphoclines in carpal joint shape in order to reconstruct adapiform positional behavior. Extant vertical clingers, slow climbers, and arboreal quadrupeds differ significantly from one another in length of the m flexor carpi ulnaris lever arm, shape of the midcarpal joint articular surface, and size and divergence of the pollical carpometacarpal articulation. These morphological differences are functionally related to differential requirements for wrist flexion, midcarpal mobility and stability, and pollical grasping, respectively. Adapis, Notharctus, and Smilodectes share with living arboreal quadrupeds a tall pisiform body, a mediolaterally flat midcarpal joint surface, and a relatively unexpanded thumb joint. Functionally, these features are related to flexing the wrist from extended positions during palmigrade, quadrupedal locomotion, increasing midcarpal joint stability during quadrupedal, weight-bearing postures, and grasping arboreal supports of predominantly horizontal and oblique orientation. The Messel adapiform (genus indet.) shares certain features of the midcarpal and pollical carpometacarpal articulations with extant vertical clingers, suggesting that this taxon used vertical substrates more frequently than other adapiforms.

  19. A 5-year Evaluation and Results of Treatment of Chronic Llocked Dislocations of the Shoulder Joint

    Directory of Open Access Journals (Sweden)

    Syawash Mirsaid Ghazi

    2008-11-01

    Full Text Available Background:Chronic neglected dislocation of the shoulder joint can be defined as a neglected dislocation for more than a 3 week period.However, it has been shown that the negligence could range from a 24 hour period to 6 months1. Depending on age,signs, symptoms,etiology and types of dislocation, conservative treatment or surgical intervention could be considered.Methods: In this study, 16 patients (13 were male and 3 were female were treated with chronic shoulder dislocations, 3 of which had bilateral dislocations. The age of this group ranged from 13-65 years with a mean age of 34 years. These patients were treated by closed or open reduction, either anterior, posterior or both approaches. Of 19 dislocations, 6 were anterior unilateral, 7 posterior unilateral, 1 anterior bilateral and 2 posterior bilateral dislocations. The mean period between dislocations and treatments was 3 months (from 4 weeks to 11 months,And the mean follow up period was 40 months (from 21 months to 5 years.Results: This study has shown that treatment varies according to pathology. In  this study the mean size of head defects was 35% and the extent of severity determined the approach. Findings at the last follow up were assessed according to Rowe and Zarins score and of the 19 shoulders assessed, 9 showed good and 10 showed excellent results. There was no recurrence of the dislocation in any patient.Conclusion:In some selected instances, open reduction of a chronic locked neglected shoulder dislocation of a 6 months period or more in young patients is recommended.This method is, however, contraindicated in elderly patients; in such cases a shoulder prosthesis is indicated.  

  20. A case study of an axillary artery pseudoaneurysm following anterior dislocation of the glenohumeral joint: A rare presentation on plain film radiographs

    International Nuclear Information System (INIS)

    Whittam, Katie; Hardy, Maryann

    2007-01-01

    Axillary pseudoaneurysm is a rare but important complication of anterior glenohumeral joint dislocation. Diagnosis of axillary pseudoaneurysm is predominantly undertaken following clinical examination but where diagnosis is uncertain, Doppler ultrasound is the imaging examination of choice to confirm diagnosis. In this case study, the initial clinical signs of axillary pseudoaneurysm were masked by the presenting trauma and, although findings indicative of pseudoaneurysm were present on late plain film images, they were not immediately recognised. Misdiagnosis or delayed diagnosis of axillary pseudoaneurysm may result in upper limb morbidity or patient mortality. Consequently, the prompt and accurate identification of an axillary pseudoaneurysm on plain film radiographs, although rare, is essential. Yet for inexperienced film readers, correctly identifying an axillary pseudoaneurysm can be difficult due to its apparent similarity to other pathologies. This article will highlight the differences in radiological appearances between a pseudoaneurysm and a gleno-humeral joint effusion to raise radiographer awareness of the risks and clinical signs of an axillary pseudoaneurysm post gleno-humeral joint dislocation and discuss the difficulties encountered in its diagnosis. Finally, this review will evaluate current diagnostic practices in comparison with best practice, as identified in the literature [Fitzgerald JF, Keates J. False aneurysm as a late complication of anterior shoulder dislocation. Ann Surg 1975;6:785-6; Drury JK, Scullion JE. Vascular complications of anterior dislocation of the shoulder. Br J Surg 1980;67(8):579-81. Waxman DL, France MP, Douglas T, Harryman I. Late lateral displacement of the humeral head after closed reduction of dislocation: a sign of vascular injury. J Bone Joint Surg 1996;78(6):907-10

  1. Secondary infection of haematoma following closed acromioclavicular joint dislocation

    Science.gov (United States)

    Dupley, Leanne; Berg, Andrew James; Mohil, Randeep

    2016-01-01

    An unusual case of a patient presenting with a large infected haematoma following a traumatic grade II acromioclavicular joint dislocation is reported. Diagnosis of this rare complication, of an otherwise common self-limiting injury, was delayed until 19 days postinjury despite several presentations during this time with worsening swelling and pain. The patient was found to have significant tissue destruction by the time washout was performed and required multiple procedures to treat the infection. This case highlights the need for a high index of suspicion for complications, even following common self-limiting injuries, when patients represent with symptoms that do not fit the usual natural history of the condition, particularly if they have risk factors for bleeding and infection. PMID:26786526

  2. Management of Chronic Recurrent Dislocation of Temporomandibular Joint Using 'U' Shaped Graft: A New Restrictive Technique.

    Science.gov (United States)

    Gadre, Kiran; Singh, Divya; Gadre, Pushkar; Halli, Rajshekhar

    2017-06-01

    Numerous procedures have been described for the treatment of chronic recurrent dislocation of the temporo-mandibular joint (TMJ), either in the form of enhancement or restriction of the condylar movement, with their obvious merits and demerits. We present a new technique of using U shaped iliac bone graft to restrict the condylar movement and its advantages over the conventional techniques.We have used this technique successfully in 8 cases where Dautrey's procedure had failed with follow up period of 2 years. No patient complained of recurrent dislocation postoperatively. This a very simple and effective technique where other procedures have failed.

  3. [Development and clinical application of a new type of anatomical locking plate for sternoclavicular joint fracture and dislocation].

    Science.gov (United States)

    Sun, Yuanlin; Yang, Yunkang; Ge, Jianhua; Yang, Kun; Xiang, Feifan; Zhou, Ju; Liang, Jie

    2018-03-01

    To report a new type of anatomical locking plate for sternocalvicular joint, and investigate its effectiveness in treatment of sternoclavicular joint fracture and dislocation. A new type of anatomical locking plate for sternoclavicular joint was developed, which accorded with the anatomical features and biomechanical characteristics of Chinese sternoclavicular joint. By adopting the method of clinical randomized controlled study, 32 patients with the sternoclavicular joint fracture and dislocation who met the selection criteria between June 2008 and May 2015 were randomly divided into groups A and B ( n =16), and the patients were treated with new anatomic locking plate and distal radial T locking plate internal fixation, respectively. There was no significant difference between 2 groups in gender, age, injured side, body mass index, cause of injury, type of injury, the time from injury to operation, and preoperative Rockwood grading score ( P >0.05). The operation time, intraoperative blood loss, incision length, hospitalization time, and postoperative complications in 2 groups were recorded, and the effectiveness was evaluated by Rockwood grading score. The operations of 2 groups completed successfully. The operation time, intraoperative blood loss, and hospitalization time in group A were significantly less than those in group B ( P case of sternoclavicular joint pain and 2 cases of wound infection; in group B, there were 1 case of sternoclavicular joint pain, 1 case of internal fixation loosening, and 1 case of sternoclavicular joint re-dislocation; there was no significant difference in complication incidence between 2 groups ( P =1.000). The Rockwood grading scores at each time point after operation in 2 groups were significantly higher than those before operation. At 1 month after operation, the Rockwood grading score in group A was significantly higher than that in group B ( t= 2.270, P =0.031); but there was no significant difference in the Rockwood

  4. 3-D sonography for diagnosis of disk dislocation of the temporomandibular joint compared with MRI.

    Science.gov (United States)

    Landes, Constantin A; Goral, Wojciech A; Sader, Robert; Mack, Martin G

    2006-05-01

    This study determines the value of three-dimensional (3-D) sonography for the assessment of disk dislocation of the temporomandibular joint (TMJ). Sixty-eight patients (i.e.,136 TMJ) with clinical dysfunction were examined by 272 sonographic 3-D scans. An 8- to 12.5-MHz transducer, angulated by step-motor, was used after picking a volume box on 2-D scan; magnetic resonance imaging followed immediately. Every TMJ was scrutinized in closed- and open-mouth position for normal or dislocated disk position. Fifty-three patients had complete data sets, i.e., 106 TMJ, 212 examinations. Sonographic examination took 5 min, with 74% specificity (62% closed-mouth; 85% open-mouth); sensitivity 53% (62/43%); accuracy 70% (62/77%); positive predictive value 49% (57/41%); and negative predictive value 77% (67/86%). This study encourages more research on the diagnostic capacity of 3-D TMJ sonography, with the advantage of multidimensional joint visualization. Although fair in specificity and negative predictive value, sensitivity and accuracy may ameliorate with future higher-sound frequency, real-time 3-D viewing and automated image analysis.

  5. Bipolar dislocation of the clavicle

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2012-01-01

    Full Text Available Bipolar dislocation of the clavicle at acromioclavicular and sternoclavicular joint is an uncommon traumatic injury. The conservative treatments adopted in the past is associated with redislocation dysfunction and deformity. A 41 years old lady with bipolar dislocation of right shoulder is treated surgically by open reduction and internal fixation by oblique T-plate at sternoclavicular joint and Kirschner wire stabilization at acromioclavicular joint. The patient showed satisfactory recovery with full range of motion of the right shoulder and normal muscular strength. The case reported in view of rarity and at 2 years followup.

  6. Surgical treatment of acute type V acromioclavicular joint dislocations in professional athletes: an anatomic ligament reconstruction with synthetic implant augmentation.

    Science.gov (United States)

    Triantafyllopoulos, Ioannis K; Lampropoulou-Adamidou, Kalliopi; Schizas, Nikitas P; Karadimas, Eleftherios V

    2017-12-01

    Most acromioclavicular (AC) joint injuries occur in men in their third decade of life during high-speed or high-impact body contact sports. The management of acute complete AC joint dislocation is surgical. Current surgical techniques include anatomic reconstruction of the main restraints of the AC joint and aim to improve functional outcomes and to reduce the complication rate. We present 10 cases of acute type V AC joint dislocation in professional athletes treated surgically with anatomic reconstruction of the coracoclavicular and AC ligaments and augmentation with the use of a synthetic polyester tape. The minimum follow-up of the patients was 2 years (mean, 48 months; range, 24-86 months). The postoperative functional outcome was assessed at 1 year and 2 years using the Constant-Murley, American Shoulder and Elbow Surgeons, and modified University of California-Los Angeles scoring systems. In all cases, the postoperative scores were significantly improved (P < .005 in all comparisons with the preoperative scores), and all patients returned to their preinjury high level of activity 6 months postoperatively. Radiographs at 1 month and 6 months revealed the maintenance of reduction. There were no complications. According to the results of our series of patients, demanding cases of acute AC joint dislocation Rockwood type V, in professional athletes, require anatomic fixation of both coracoclavicular and AC ligaments for return to sports as soon as possible and at the preinjury level of performance. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  7. Open capsular and ligament reconstruction with semitendinosus hamstring autograft successfully controls superior and posterior translation for type V acromioclavicular joint dislocation.

    Science.gov (United States)

    Garofalo, Raffaele; Ceccarelli, Enrico; Castagna, Alessandro; Calvisi, Vittorio; Flanagin, Brody; Conti, Marco; Krishnan, Sumant G

    2017-07-01

    Appropriate surgical management for type V complete acromioclavicular (AC) joint dislocation remains controversial. The purpose of this paper is to retrospectively report the clinical and radiographic outcomes of an open surgical technique consisting for AC joint ligamentous and capsular reconstruction using autologous hamstring tendon grafts and semi-permanent sutures. Between January 2005 and December 2011, 32 consecutive patients with symptomatic type V complete AC joint dislocation underwent surgical treatment using the same technique. The median time from injury to surgery was 45 days (range 24-90). The average median postoperative clinical and radiographic follow-up time was 30 months (range 24-33). Clinical outcomes measures included the ASES score, the visual analog score (VAS), and subjective patient satisfaction score. Minimum follow-up was 2 years. ASES score increased from a median of 38.2 ± 6.2 preoperative to 92.1 ± 4.7 postoperatively (p ≤ 0.05). The median VAS score improved from 62 mm (range 45-100 mm) preoperatively to 8 mm (range 0-20 mm) at final follow-up (p ≤ 0.05). No patient experienced pain or discomfort with either direct palpation of the AC joint or with cross-body adduction. Final radiographs demonstrated symmetric AC joint contour in 25/32 (78%) patients. Seven patients (22%) radiographically demonstrated superior translation of the distal clavicle relative to the superior margin of the acromion but less than 50% of the clavicular width. 30/32 patients (93%) were able to return to their pre-injury level of work and sports activities. This novel surgical technique using a free graft and braided suture for simultaneous coracoclavicular ligament and AC joint capsular reconstruction successfully controls superior and posterior translations after type V AC joint dislocation and minimizes the incidence of persistent postoperative AC joint subluxation. Retrospective case series, Level IV.

  8. Bilateral Dislocation of Temporomandibular Joint Induced by Haloperidol Following Suicide Attempt: A Case Report

    Directory of Open Access Journals (Sweden)

    Mosa Arghand Dargahi

    2012-03-01

    Full Text Available Drug induced dystonic reactions are among common presentations of patients in emergency departments, and typically occur with antidopaminergic agents as their extra-pyramidal side effects. Dystonic reactions usually occur within the first few hours or days after commencing a drug or dose increase. Unlike other extra-pyramidal side effects, a patient may experience acute dystonic reactions (ADRs with the administration of just a single dose. Oromandibular dystonia is a subtype of dystonia which can present with perioral manifestations. In extreme cases, it can lead to temporomandibular dislocation. Haloperidol, as a high potent typical antipsychotic drug, can induce dystonia with blocking D2 dopamine receptors. The present paper reports a case of bilateral dislocation of temporomandibular joint following ingestion of haloperidol in a suicidal attempt in a 17 years old girl.

  9. Intra-articular Entrapment of Medial Epicondyle Fracture Fragment in Elbow Joint Dislocation Causing Ulnar Neuropraxia: A Case Report

    Directory of Open Access Journals (Sweden)

    Syed J

    2017-03-01

    Full Text Available Traumatic elbow dislocations in children are rare but most of them are complex dislocations, and in such dislocations, medial humerus epicondyle fractureis the most common associated injury. Fracture incarceration in the elbow joint occurs in 5-18% of medial humerus epicondyle fractures but ulnar neuropraxia is very rare. Open reduction internal fixation is indicated in medial humerus epicondyle fracture with fracture incarceration, ulnar neuropraxia, marked instability or open fracture. Operative treatment options include fragment excision and sutures, closed or open reduction and Kirschner wire fixation, open reduction and suture fixation, open reduction and smooth pin fixation, and open reduction and screw fixation. However, ulnar nerve transposition is debatable as good outcome had been reported with and without nerve transposition. We report a case of a 13-year old boy, who presented with right elbow dislocation and intra-articular entrapment of medial humerus epicondyle fracture fragment, complicated with sensory ulnar neuropraxia, following a fall onto his right outstretched hand in a motor vehicle accident. The elbow joint was reduced using close manipulative reduction but the fracture fragment remained entrapped post-reduction. The patient then underwent open reduction and screw fixation of the medial humerus epicondyle fracture without ulnar nerve transposition. He had good functional outcome six weeks after surgical intervention, with complete recovery of ulnar neuropraxia six months later. Currently, he is doing well at school and is active with his sporting activity.

  10. Ligament Augmentation and Reconstruction System Failures in Repair of Grade V Acromioclavicular Joint Dislocation

    Directory of Open Access Journals (Sweden)

    Martin K.-H. Li

    2017-01-01

    Full Text Available The Ligament Augmentation and Reconstruction System® (LARS® represents a popular synthetic anatomical reduction method for acromioclavicular joint dislocation by means of coracoclavicular ligament reconstruction. To our knowledge, no early failure has been documented in the literature. We present two unusual cases of LARS failure, one at four months after implant and the other at three weeks, without obvious causes, requiring re-do reconstruction, and discuss potential contributory factors.

  11. Dislocation of the fibular head in an unusual sports injury: a case report

    Directory of Open Access Journals (Sweden)

    Ahmad Riaz

    2008-05-01

    Full Text Available Abstract Introduction One of the primary functions of the proximal tibiofibular joint is slight rotation to accommodate rotational stress at the ankle. Proximal tibiofibular joint dislocation is a rare injury and accounts for less than 1% of all knee injuries. This dislocation has been reported in patients who had been engaged in football, ballet dancing, equestrian jumping, parachuting and snowboarding. Case presentation A 20-year-old man was injured whilst playing football. He felt a pop in the right knee and was subsequently unable to bear weight on it. The range of movement in his knee joint was limited. Anterior-posterior and lateral X-rays of the knee revealed anterolateral dislocation of the proximal tibiofibular joint. Comparison views confirmed the anterolateral dislocation. He had a failed manipulation under anaesthesia and the joint needed an open reduction in which the fibular head was levered back into place. Operative findings revealed a horizontal type of joint. Conclusion An exceedingly rare dislocation of a horizontal type of proximal tibiofibular joint was presented following a football injury. This dislocation was irreducible by a closed method.

  12. A variant neglected Type IIIA dorsal dislocation of first metatarsophalangeal joint. A case report.

    Science.gov (United States)

    Ainhoa, Toro-Ibarguen; Moreno-Beamud, Jose Alberto; Martínez-Leocadio, Miguel-Ángel; Candel-García, Luciano; Díaz-Martín, Andrés; Delgado-Díaz, Emilio

    2015-03-01

    We present a rare injury consisting of a neglected, irreducible, dislocation of the first metatarsophalangeal joint that was diagnosed 4 months after the injury. An open reduction was necessary from the beginning. Patient returned to full activity without pain or disability, so a good prognosis despite the delayed diagnosis was achieved. We are unaware of previous reports in the literature describing this unusual variant. Copyright © 2014 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  13. Dislocation: First Aid

    Science.gov (United States)

    ... or a collision during contact or high-speed sports. Dislocation usually involves the body's larger joints. In adults, the most common site of the injury is the shoulder. In children, it's the elbow. ...

  14. [EFFECTIVENESS COMPARISON OF CORACOCLAVICULAR LIGAMENT RECONSTRUCTION BETWEEN BY AUTOLOGOUS AND ALLOGENEIC TENDON GRAFTS COMBINED WITH HOOK PLATE FIXATION FOR TREATING ACROMIOCLAVICULAR JOINT DISLOCATION].

    Science.gov (United States)

    Yin, Fei; Sun, Zhenzhong; Wei, Xuming; Liu, Xueguang; Zhou, Ming; Zhuang, Yin; Song, Sheng

    2016-05-08

    To compare the effectiveness of coracoclavicular ligament reconstruction between by using autologous plantaris tendon graft combined with hook plate fixation and allogeneic tendon graft combined with hook plate fixation for treating acromiocavicular joint dislocation. Thirty-three patients with acromioclavicular joint dislocation who accorded with the inclusion criteria between January 2013 and June 2014 were assigned into 2 groups. The patients were treated with autologous plantaris tendon graft combined with hook plate fixation in group A ( n =17), and with allogeneic tendon graft combined with hook plate fixation in group B ( n =16). Thirteen-one patients was followed up more than 12 months (15 in group A and 16 in group B). There was no significant difference in gender, age, cause of injury, sides, time between injury and surgery, and type of dislocation ( P >0.05). The assessments included operation time, hospitalization time, hospitalization expenses, shoulder range of motion, gap of acromioclavicular, Constant-Murley scores, and visual analogue scale (VAS) for pain. The operation time of group A was significantly longer than that of group B, and the hospitalization expense was significantly lower than that of group B ( P 0.05). No redislocation of acromioclavicular joint and rejection reaction occurred during follow-up. At last follow-up, there was no significant difference in shoulder range of motion, Constant-Murley score, and VAS score between 2 groups ( P >0.05). Coracoclavicular ligament reconstruction by autologous plantaris tendon or allogeneic tendon graft combined with hook plate fixation for the treatment of acromioclavicular joint dislocation can achieve good effectiveness. The appropriate treatment should be chosen according to the patient's economic situation.

  15. [Treatment of complete acromioclavicular joint dislocation with transfer of the medial half of the coracoacromial ligament to reconstruct the coracoclavicular ligament].

    Science.gov (United States)

    Dong, Wen-Wei; Shi, Zeng-Yuan; Liu, Zheng-Xin; Mao, Hai-Jiao

    2015-04-01

    To explore the operation methods and clinical effects of transfer of the medial half of the coracoacromial ligament to reconstruct the coracoclavicular ligament in treating complete acromioclavicular joint dislocation. From January 2006 to June 2012,26 patients with acute complete acromioclavicular joint dislocation underwent surgery. Transfer of the medial half of the coracoacromial ligament to reconstruct the coracoclavicular ligament, additional clavical hoot plate and Kirschner wires fixation, were performed in all the patients. Among the patients, 18 patients were male and 8 patients were female, with an average age of 36.7 years old (ranged from 25 to 51 years). The duration from injury to operation was from 3 to 12 days with an average of 5 days. According to the Rockwood classification, 4 cases were grade III and 22 cases were grade V . Clinical manifestation included local swelling, tenderness with snapping, limitation of shoulder joint motion. In preoperative bilateral shoulder joint X-rays, the injured coracoclavicular distance was (16.2 ± 5.0) mm which was significantly wider than that of uninjured sides (7.6 ± 1.0) mm. Clinical results were evaluated according to X-rays and Constant-Murley score. All incisions obtained primary healing after operation without complication of infection, internal fixation breakage, redislocation. All the patients were followed up from 12 to 30 months with an average of 18 months. Kirschner wires and internal fixation plate were removed at 1 month and 8-10 months after operation, respectively. At final follow-up, the motion of shoulder joint recovered to normal and a no pain joint was obtained. According to Constant-Murley score, 24 cases got excellent results and 2 cases good. There was no significant difference after operation between the injured coracoclavicular distance and the uninjured contralateral side [(7.7 ± 1.2) mm vs (7.6 ± 1.0) mm), P > 0.05]. Transfer of the medial half of the coracoacromial ligament to

  16. Proximal tibiofibular dislocation: a case report and review of literature

    NARCIS (Netherlands)

    Nieuwe Weme, R. A.; Somford, M. P.; Schepers, T.

    2014-01-01

    An isolated dislocation of the proximal tibiofibular joint is uncommon. The mechanism of this injury is usually sports related. We present a case where initial X-rays did not show the tibiofibular joint dislocation conclusively. It was diagnosed after comparative bilateral AP X-rays of the knees

  17. Comparison of the Tight Rope Technique and Clavicular Hook Plate for the Treatment of Rockwood Type III Acromioclavicular Joint Dislocation.

    Science.gov (United States)

    Cai, Leyi; Wang, Te; Lu, Di; Hu, Wei; Hong, Jianjun; Chen, Hua

    2018-06-01

    Acromioclavicular joint dislocation is one of the most common shoulder problems and may lead to instability or degenerative changes. The aim of this study was to compare the clinical outcomes of the Tight Rope system and clavicular hook plate for Rockwood type III acromioclavicular joint dislocation in adults. This was a prospective, randomized study in a hospital setting. From January 2012 to December 2014, 69 patients with type III injury were reviewed. Patients were randomly divided into two groups: Group A was treated using the TightRope system and Group B with the clavicular hook plate. All participants were followed up for 12 months. Clinical outcomes, radiological results and postoperative complications were recorded. The length of incision was significantly shorter in Goup A than that in Group B. The blood loss of surgery was significantly less in the Group A. Significant difference could be found between the two groups regarding the Visual Analogue Scale scores one day after surgery, at the 3 and 12 months follow-up. There were no differences according to the improvement of the Constant-Murley score and the coracoclavicular distance between the groups. The two groups have similar clinical and radiological outcomes. Both treatments could relieve the pain of dislocation, improve the function of Acromioclavicular joint and rectify the coracoclavicular distance measured in plain films. However, the TightRope system exhibited some advantages in terms of length of incision, blood loss of surgery, the pain postoperatively and no need for a second surgery.

  18. Treatment of Rockwood type III acromioclavicular joint dislocation using autogenous semitendinosus tendon graft and endobutton technique

    Directory of Open Access Journals (Sweden)

    Ye G

    2016-01-01

    Full Text Available Gang Ye, Chao-An Peng, Hua-Bin Sun, Jing Xiao, Kang Zhu Department of Orthopedics, the People’s Hospital of Huangpi District, Wuhan City, People’s Republic of China Background: The aim of this study was to evaluate the therapeutic effect of autogenous semitendinosus graft and endobutton technique, and compare with hook plate in treatment of Rockwood type III acromioclavicular (AC joint dislocation.Methods: From April 2012 to April 2013, we treated 46 patients with Rockwood type III AC joint dislocation. Patients were randomly divided into two groups: Group A was treated using a hook plate and Group B with autogenous semitendinosus graft and endobutton technique. All participants were followed up for 12 months. Radiographic examinations were performed every 2 months postoperatively, and clinical evaluation was performed using the Constant–Murley score at the last follow-up.Results: Results indicated that patients in Group B showed higher mean scores (90.3±5.4 than Group A (80.4±11.5 in terms of Constant–Murley score (P=0.001. Group B patients scored higher in terms of pain (P=0.002, activities (P=0.02, range of motion (P<0.001, and strength (P=0.004. In Group A, moderate pain was reported by 2 (8.7% and mild pain by 8 (34.8% patients. Mild pain was reported by 1 (4.3% patient in Group B. All patients in Group B maintained complete reduction, while 2 (8.7% patients in Group A experienced partial reduction loss. Two patients (8.7% encountered acromial osteolysis on latest radiographs, with moderate shoulder pain and limited range of motion.Conclusion: Autogenous semitendinosus graft and endobutton technique showed better results compared with the hook plate method and exhibited advantages of fewer complications such as permanent pain and acromial osteolysis. Keywords: Rockwood type III acromioclavicular joint dislocation, autogenous semitendinosus graft, endobutton, hook plate

  19. Spinopelvic Fixation of Sacroiliac Joint Fractures and Fracture-Dislocations: A Clinical 8 Years Follow-Up Study.

    Science.gov (United States)

    Sobhan, Mohammad R; Abrisham, Seyed Mohammad J; Vakili, Mahmood; Shirdel, Saeed

    2016-10-01

    Pelvic ring injuries and sacroiliac dislocations have significant impacts on patient's quality of life. Several techniques have been described for posterior pelvic fixation. The current study has been designed to evaluate the spinopelvic method of fixation for sacroiliac fractures and fracture-dislocations. Between January 2006 and December 2014, 14 patients with sacroiliac joint fractures, dislocation and fracture-dislocation were treated by Spinopelvic fixation at Shahid Sadoughi Training Hospital, Yazd, Iran. Patients were seen in follow up, on average, out to 32 months after surgery. Computed tomographic (CT) scans of patients with sacral fractures were reviewed to determine the presence of injuries. A functional assessment of the patients was performed using Majeed's score. Patient demographics, reduction quality, loss of fixation, outcomes and complications, return to activity, and screw hardware characteristics are described. The injury was unilateral in 11 (78.5%) patients and bilateral in 3 (21.5%). Associated injuries were present in all patients, including fractures, dislocation and abdominal injuries. Lower limb length discrepancy was less than 10 mm in all patients except two. Displacement, as a measure of quality of reduction was less than 5 mm in 13 patients. The mean Majeed score was 78/100. Wound infection and hardware failure were observed in 3 (21.4%) and 1 (7.1%) cases, respectively. In this study most patients (85%) return to work postoperatively. According to the findings, spinopelvic fixation is a safe and effective technique for treatment of sacroiliac injuries. This method can obtain early partial to full weight bearing and possibly reduce the complications.

  20. OK-432 (Picibanil) sclerotherapy for recurrent dislocation of the temporomandibular joint in elderly edentulous patients: Case reports.

    Science.gov (United States)

    Matsushita, Kazuhiro; Abe, Takae; Fujiwara, Toshikatsu

    2007-09-01

    Dislocation of the temporomandibular joint (TMJ) is a thorny problem not only for a patient but also a doctor. Especially for the elderly edentulous patients, it is very hard to treat the condition although there are many surgical and non-surgical procedures. We successfully treated it in two elderly edentulous patients by injection of OK-432 as a sclerosing agent.

  1. Superior shoulder suspensory complex fracture dislocation case report

    International Nuclear Information System (INIS)

    Lidgett, T.; Bate, E.; Pittock, L.

    2017-01-01

    Background: Acromioclavicular joint dislocation can be more complex than it first appears. The presented case had an unusual combination of injuries to the superior shoulder suspensory complex, which yielded some interesting learning points. Case summary: The injuries were sustained after a fall from a push bike and included acromioclavicular dislocation with coracoid process, clavicle and acromion process fractures. These were identified on the initial X-ray examination, which was followed by computed tomography for surgical planning. The injuries were successfully treated by internal fixation. Conclusion: The unexpected complexity of the injuries could have led to subtle but important findings being overlooked. This case highlights the importance of a thorough search strategy, consideration of injury biomechanics and knowledge of associated injuries. - Highlights: • Search for associated fractures in acromioclavicular joint dislocation. • Assess the clavicle, acromion process and coracoid process in particular. • Do not end the shoulder X-ray examination after seeing one injury. • Both axial and cranially angulated anteroposterior projections are beneficial. • Acromioclavicular joint fracture dislocation treatment may require further research.

  2. [COMPARISON OF EFFECTIVENESS BETWEEN TWO OPERATIVE TECHNIQUES OF CORACOCLAVICULAR LIGAMENT RECONSTRUCTION FOR TREATMENT OF Tossy TYPE III ACROMIOCLAVICULAR JOINT DISLOCATION].

    Science.gov (United States)

    Tang, Hongwei; Gao, Sheng; Yin, Yong; Li, Yunfei; Han, Qingtian; Li, Huizhang

    2015-11-01

    To evaluate and compare the effectiveness of double Endobutton technique and suture anchor combined Endobutton plate in the treatment of Tossy type III acromioclavicular joint dislocation. Between May 2010 and March 2014, a retrospective study was preformed on 56 patients with Tossy type III acromioclavicular joint dislocation. The coracoclavicular ligament was reconstructed with double Endobutton technique in 31 cases (Endobutton group), and with suture anchor combined Endobutton plate in 25 cases (Anchor group). There was no significant difference in age, gender, injury causes, injury side, associated injury, medical comorbidities, and disease duration between 2 groups (P>0.05). The operation time, medical device expenses, postoperative complications, preoperative and postoperative Constant-Murley scores, and postoperative Karlsson grading of the injured shoulder were compared between 2 groups. The average operation time in Endobutton group was significantly greater than that in Anchor group (t = 4.285, P = 0.000); there was no significant difference in the medical device expenses between 2 groups (t = 1.555, P = 0.126). Primary healing of incision was obtained in all patients of 2 groups; no early complications of infection and skin necrosis occurred. All patients were followed up 15.6 months on average (range, 11-35 months). During follow-up, some loss of reduction and ectopic ossification in the coracoclavicular gap were observed in 1 case and 6 cases of Endobutton group, respectively. No recurrence of acromioclavicular joint dislocation, implant fixation loosening and broken, and secondary fractures occurred in the other patients. There was significant difference in the incidence of postoperative complications between 2 groups (P = 0.013). Constant-Murley scores of the injured shoulder significantly increased at 9 months after operation when compared with preoperative values in 2 groups (P 0.05). At last follow-up, there was no significant difference in

  3. Clinical factors that affect perceived quality of life in arthroscopic reconstruction for acromioclavicular joint dislocation.

    Science.gov (United States)

    Abat, F; Gich, I; Natera, L; Besalduch, M; Sarasquete, J

    To analyse the results of arthroscopic repair of acromioclavicular dislocation in terms of health-related quality of life. Prospective study of patients with acromioclavicular dislocation Rockwood grade iii-v, treated arthroscopically with a mean follow up of 25.4 months. The demographics of the series were recorded and evaluations were performed preoperatively, at 3 months and 2 years with validated questionnaires as Short Form-36 Health Survey (SF-36), visual analogue scale (VAS), The Disabilities of the Arm, Shoulder and Hand (DASH), Constant-Murley Shoulder Outcome Score (Constant) and Walch-Duplay Score (WD). Twenty patients, 17 men and 3 women with a mean age of 36.1 years, were analysed. According to the classification of Rockwood, 3 patients were grade iii, 3 grade iv and 14 grade v. Functional and clinical improvement was detected in all clinical tests (SF-36, VAS and DASH) at 3 months and 2 years follow up (Pacromioclavicular joint dislocation grades iii-v was not influenced by gender, age, grade, displacement, handedness, evolution of the VAS, scoring of the Constant or by the WD. However, it is correlated with the evolution in the DASH score. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Spinopelvic Fixation of Sacroiliac Joint Fractures and Fracture-Dislocations: A Clinical 8 Years Follow-Up Study

    Directory of Open Access Journals (Sweden)

    Mohammad R. Sobhan

    2016-10-01

    Full Text Available Background: Pelvic ring injuries and sacroiliac dislocations have significant impacts on patient’s quality of life. Several techniques have been described for posterior pelvic fixation. The current study has been designed to evaluate the spinopelvic method of fixation for sacroiliac fractures and fracture-dislocations.   Methods: Between January 2006 and December 2014, 14 patients with sacroiliac joint fractures, dislocation and fracture-dislocation were treated by Spinopelvic fixation at Shahid Sadoughi Training Hospital, Yazd, Iran. Patients were seen in follow up, on average, out to 32 months after surgery. Computed tomographic (CT scans of patients with sacral fractures were reviewed to determine the presence of injuries. A functional assessment of the patients was performed using Majeed’s score. Patient demographics, reduction quality, loss of fixation, outcomes and complications, return to activity, and screw hardware characteristics are described Results: The injury was unilateral in 11 (78.5% patients and bilateral in 3 (21.5%. Associated injuries were present in all patients, including fractures, dislocation and abdominal injuries. Lower limb length discrepancy was less than 10 mm in all patients except two. Displacement, as a measure of quality of reduction was less than 5 mm in 13 patients. The mean Majeed score was 78/100. Wound infection and hardware failure were observed in 3 (21.4% and 1 (7.1% cases, respectively. In this study most patients (85% return to work postoperatively. Conclusion: According to the findings, spinopelvic fixation is a safe and effective technique for treatment of sacroiliac injuries. This method can obtain early partial to full weight bearing and possibly reduce the complications.

  5. [Case-control study on measurement of coracoclavicular and acromioclavicular ligament injuries during internal fixation operation for the treatment of fresh acromioclavicular joint dislocation of Tossy type III].

    Science.gov (United States)

    Guan, Ting-Jin; Sun, Peng; Zheng, Liang-Guo; Qi, Xiang-Yang

    2014-01-01

    To study measurement methods of acromioclavicular and coracoclavicular ligament injuries,its therapeutic effects and complications during internal fixation operation for the treatment of fresh acromioclavicular joint dislocations of Tossy type III. From July 2003 to May 2012,127 patients with acromioclavicular joint dislocations of Tossy type III were treated with wire fixation from coracoid process to clavicle or hook-plate fixation. The patients were divided into group A (63 cases) and group B (64 cases) according to whether acromioclavicular ligament and coracoclavicular ligament were repaired or not. In group A (ligaments repaired), there were 39 males and 24 females with an average age of (33.25 +/- 8.46) years old (ranged from 17 to 59 years). And in group B (no ligaments repaired), there were 41 males and 23 females with an average age of (34.10 +/- 7.19) years (ranged from 19 to 57 years). The operation times, intraoperative blood loss, postoperative infections, internal fixation failure, recurrence and other complications, together with therapeutic effects were compared between two groups. The outcome was analyzed according to Karlsson standard. In group A, 54 patients got an excellent result and 9 good according to Karlsson standard;the average operative time was (55.90 +/- 26.56) min; the average intraoperative bleeding amount was (99.80 +/- 50.30) ml; 1 patient had wire broken without re-dislocation at 16 weeks after operation, 3 patients got wound fat liquefaction and recovered after treatment, 1 patient had pain after shoulder joint motion and pain disappeared after implants were taken out. In group B, 52 patients got an excellent result and 12 good according to Karlsson standard; the average operative time was (49.50 +/- 23.14) min; the average intraoperative bleeding amount was (87.30 +/- 46.41) ml; 2 patients got wound fat liquefaction, and 2 patients had pain after shoulder joint motion. All the patients were followed up, and the duration ranged

  6. Traumatic hip dislocation: early MRI findings

    International Nuclear Information System (INIS)

    Laorr, A.; Greenspan, A.; Anderson, M.W.; Moehring, H.D.; McKinley, T.

    1995-01-01

    Objective of this study was to present the spectrum of early magnetic resonance imaging (MRI) findings following traumatic dislocation of the femoral head, and to identify any associated injuries. Prospective MRI of both hips was performed on 18 patients within 5 weeks of a traumatic femoral head dislocation. The interval between the time of injury and the imaging studies ranged from 2 to 35 days. Posterior dislocation was present in 14 patients and anterior dislocation in 4 patients. In the majority of cases, we performed axial T1, coronal T1, and coronal T2 * (MPGR) sequences. MRI can effectively identify and quantify the muscle injury and joint effusion that invariably accompany traumatic hip dislocations. It is also useful for demonstrating trabecular bone contusion (trabecular injury) and iliofemoral ligament injury, which occur commonly with acute hip dislocation. (orig./VHE)

  7. Carpometacarpal subchondral cysts due to repetitive movements in shoemaker: a case report.

    Science.gov (United States)

    Tonini, Stefano; Candura, Stefano M; Lanfranco, Andrea; Mennoia, N Valerio

    2011-12-01

    Subchondral carpometacarpal cysts are classic and almost pathognomonic lesions found in workers using vibrating instruments over prolonged periods of time. We present the case of a 53-year-old woman who worked for 30 years sewing shoe uppers, a task which required grasping firmly a pear-shaped handle awl and pushing it through the leather upper and the sole of the shoe, with combined flexion and supination movement of the wrist. After approximately 20 years of working, the patient noted gradual onset of paresthesias in the dominant (right) hand, with increasing difficulty in grasping the awl. Subsequent diagnosis of carpal tunnel syndrome was confirmed by electrophysiologic testing and its surgical release was performed. Nevertheless, hand pain, paresthesias and weakness persisted. Ultrasound of the snuffbox tendons excluded DeQuervain tenosynovitis. Radiographic imaging of the symptomatic hand showed carpometacarpal subchondral cystic formations. In addition to demonstrating the usefulness of radiographic imaging in patients with persistent hand pain post-carpal release, this case is important in illustrating that repetitive movements with high pressure over the palmar carpal area may cause bone cysts, even if the subjects do not use vibrating tools.

  8. Traumatic anterior hip dislocation in a 12-year-old child

    Directory of Open Access Journals (Sweden)

    Gupta Vinay

    2013-04-01

    Full Text Available 【Abstract】Hip dislocation in children can occur congenitally in isolation or in conjunction with other con-genital abnormalities. Traumatic hip dislocations in children are relatively uncommon and anterior dislocation of hip joint is even rarer. We report such a case following unusual mode of injury in a 12-year-old child. The patient underwent suc-cessful emergent closed reduction of left hip. The clinical course and follow-up assessment of the patient was other-wise uneventful. At 2 years’ follow-up there was no evi-dence of osteoarthritis, coxa magna, heterotrophic calcification, in congruency of the joints or avascular ne-crosis of the head of femur. Key words: Hip; Dislocations; Child

  9. [CT measurement and clinical application of double-row suture anchor reconstruction for the treatment of Tossy type III acromioclavicular joint dislocation].

    Science.gov (United States)

    Zhang, Chuan-Kai; Liu, Chen; Han, Bing; Feng, Hui; Chen, Qi-Zhong; Sunx, Sun Yi-Yan

    2017-04-25

    To study feasibility and reliability of reconstruction of the acromioclavicular ligament with double-row suture anchor for the treatment of acromioclavicular joint dislocation through coracoid coronal CT measurement, and to provide a new operation method for treating acromioclavicular joint dislocation. Total 60 healthy people received CT examination of shoulder joint, including 30 males and 30 females, ranging in age from 18 to 50 years old. The coronal width, thickness and 20 degree camber angle in the medial part of the toot of coronal were measured using CT scan. The results were applied to clinical treatment for 12 patients with acromioclavicular joint dislocation of Tossy III type. The width in the medial part of the root of the coracoid was(17.65±1.82) mm(left side) and (17.67±1.80) mm(right side) in males; (16.55±1.78) mm(left side) and (16.52±1.74) mm (right side) in females. The vertical thickness of the roots of the coracoid: (13.11±2.11) mm(left side) and (13.16±2.09) mm(right side) in males;(12.79±2.21) mm(left side) and (12.76±2.19) mm (right side) in females. The thickness of 20 degrees camber angle of the coracoid roots: (16.32±1.74) mm (left side) and (16.30±1.69) mm(right side) in males; (15.68±1.44) mm(left side) and (15.67±1.43) mm(right side) in females. Total 12 patients were treated with anchor nail with extraversion 20 degrees. The postoperative X-ray films showed bone anchors were located in the coracoid process, no bone splitting. Double-row suture anchor of 5 mm diameter nails can be placed into coracoid with extraversion 20 degrees, which is safety.

  10. [Design and clinical application of the drilling guide in the treatment of acromioclavicular joint dislocation with closed reduction and Kirschner fixation].

    Science.gov (United States)

    Zhou, Song; Hao, Yong-qiang; Shi, Xiao-lin; Zhao, Huan-li; Gao, Kai-tuo; Sun, Jin-xu

    2011-03-01

    To investigate a drilling guide in the treatment of acromioclavicular joint dislocation with closed reduction and Kirschner fixation and explore the therapeutic effect. From June 2008 to December 2009, 36 patients with acromioclavicular joint dislocation (Tossy III) were treated with closed reduction and Kirschner fixation using a self-designed drilling guide as well as percutaneous repair of acromioclavicular joint. Among the patients, 24 patients were male and 12 patients were female,ranging in age from 20 to 61 years, averaged 38.6 years. The duration from injury to operation ranged from 3.5 to 72 h,with a mean of 15.2 h. No clavicle fracture was found in all cases. The operative time, intra-operative bleeding and therapeutic effects were observed. There were no complications including neurovascular problems. The mean operating time were 20 min,mean blood loss were about 10 ml. According to the observation of postoperative X-ray examination, all Kirschners in acromioclavicular joint were in place. All Kirschners were removed in 6 postoperative weeks. All the patients were followed up ranging from 2 to 26 months (averaged 14.3 months). According to the Karlsson standard,22 patients got an excellent result, 13 good and 1 poor. This method has following advantages: easy operation and fixation; minimum injuries to articular surface; and which would be widely used in clinical practice.

  11. Medial subtalar dislocation: Case report

    Directory of Open Access Journals (Sweden)

    Manojlović Radovan

    2010-01-01

    Full Text Available Introduction. Subtalar dislocation (SI is a term that refers to an injury in which there is dislocation of the talonavicular and talocalcanear joint, although the tibiotalar joint is intact. Case Outline. A case of medial subtalar dislocation as a result of basketball injury, so-called 'basketball foot', is presented. Closed reposition in i.v. anaesthesia was performed with the patient in supine position and a knee flexed at 90 degrees. Longitudinal manual traction in line of deformity was carried out in plantar flexion. The reposition continued with abduction and eversion simultaneously increasing dorsiflexion. It was made in the first attempt and completed instantly. Rehabilitation was initiated after 5 weeks of immobilization. One year after the injury, the functional outcome was excellent with full range of motion and the patient was symptom-free. For better interpretation of roentgenogram, bone model of subtalar dislocation was made using the cadaver bone. Conclusion. Although the treatment of such injury is usually successful, diagnosis can be difficult because it is a rare injury, and moreover, X-ray of the injury can be confusing due to superposition of bones. Radiograms revealed superposition of the calcaneus, tarsal and metatarsal bones which was radiographically visualized in the anterior-posterior projection as one osseous block inward from the talus, and on the lateral view as in an osteal block below the tibial bone. Prompt recognition of these injuries followed by proper, delicately closed reduction under anaesthesia is crucial for achieving a good functional result in case of medial subtalar dislocation.

  12. Base of coracoid process fracture with acromioclavicular dislocation in a child

    Science.gov (United States)

    2010-01-01

    Fracture of the coracoid process is a rare injury. It can be easily missed when associated with other injuries to the shoulder girdle, for instance, acromioclavicular joint (ACJ) dislocation. Clinical attention is easily drawn to the more obvious ACJ dislocation, hence, the need for further radiological evaluation. We report an unusual case of fracture of the base of coracoid process associated with a true acromioclavicular joint dislocation in a 12 year old boy, with no separation of the epiphyseal plate, as one might expect. Treatment also remains controversial. Our patient underwent open reduction internal fixation of the acromioclavicular joint and coracoid process. He subsequently made an uneventful progress with pain free full range of shoulder movement at 5 months, and was discharged at 9 months. PMID:20955595

  13. Ligamentous and capsular injuries to the metacarpophalangeal joints of the hand.

    Science.gov (United States)

    Shah, Smiresh Suresh; Techy, Fernando; Mejia, Alfonso; Gonzalez, Mark H

    2012-01-01

    The mechanism of dorsal dislocation of the metacarpophalangeal (MCP) joint is with forced hyperextension of the joint and the main structure injured is the volar plate. A simple dislocation can be reduced by closed means whereas a complex dislocation cannot. Care must be taken not to put traction across the joint, which may cause the volar plate to slip into the joint, converting a simple dislocation into a complex dislocation. Volar dislocations are rare and mainly treated nonoperatively. Sagittal band injuries can be treated with extension splinting or surgical management with direct repair or reconstruction. A locked MCP joint can usually be treated with closed manipulation. This article discusses these injuries and management options.

  14. Arthroscopically assisted reduction of acute acromioclavicular joint dislocation using a single double-button device: Medium-term clinical and radiological outcomes.

    Science.gov (United States)

    Issa, S-P; Payan, C; Le Hanneur, M; Loriaut, P; Boyer, P

    2018-02-01

    Double-button devices for endoscopic management of acute acromioclavicular joint dislocation (ACJD) provide satisfactory short-term functional and radiological results. However, little exists in the literature regarding the long- and medium-term results of these implants, especially regarding the evolution of the acromioclavicular joint (ACJ). Satisfactory and steady long- and medium-term outcomes can be achieved in patients with acute ACJD undergoing endoscopically assisted ACJ repair using a single double-button device. A retrospective single-center study was conducted in patients with acute Rockwood III and IV ACJD treated endoscopically with a single double-button device from October 2008 to October 2010, allowing a minimum 5-year follow-up. Functional evaluation used Constant and Quick-DASH scores. Clinical evidence of dislocation recurrence was combined with bilateral Zanca views to assess coracoclavicular distance. Acromioclavicular osteoarthritis was evaluated on the Paxinos test and Zanca views. Nineteen of the 25 operated patients were seen at a mean 76.9±8.5 months' follow-up. Mean age was 34.4±8.3 years. Mean Constant and Quick-DASH scores were 96.2±5.1 and 0.9±1.6 points, respectively. Four patients had a recurrence of their initial dislocation, 3 of whom had positive Paxinos test, whereas the 15 patients without recurrence had a negative test (p=0.004). Five patients had radiological evidence of ACJ osteoarthritis: all 4 patients with recurrence and 1 without (p=0.001). Long- and medium-term radioclinical outcome of endoscopically assisted management of acute ACJD using a single double-button device seems to be satisfactory and steady over time. Recurrence of the initial dislocation appears to be related to onset of degenerative ACJ arthropathy. Therapeutic type IV-Retrospective case series. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  15. Subluxation and dislocation of the hip in children with spina bifida (review

    Directory of Open Access Journals (Sweden)

    A. G. Baindurashvili

    2013-01-01

    Full Text Available Subluxation or dislocation of the hip joint develops in 30-50% children with spina bifida during the first 2-3 years of life. These problems results from force disbalance between muscle group and other structural changes of the hip and pelvis components of the joint. The goal of treatment subluxation and dislocation of the hip joint in children with spina bifida is to make comfortable daily functions, eliminate the pain, provide the mobility and social independent. Management of subluxation and dislocation in children with spina bifida had changed in the last years because of the analysis long-term results. Indications for surgical treatment were determined more clearly, what made the results of treatment better.

  16. Results of Operative and Nonoperative Treatment of Rockwood Types III and V Acromioclavicular Joint Dislocation

    Science.gov (United States)

    Joukainen, Antti; Kröger, Heikki; Niemitukia, Lea; Mäkelä, E. Antero; Väätäinen, Urho

    2014-01-01

    Background: The optimal treatment of acute, complete dislocation of the acromioclavicular joint (ACJ) is still unresolved. Purpose: To determine the difference between operative and nonoperative treatment in acute Rockwood types III and V ACJ dislocation. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: In the operative treatment group, the ACJ was reduced and fixed with 2 transarticular Kirschner wires and ACJ ligament suturing. The Kirschner wires were extracted after 6 weeks. Nonoperatively treated patients received a reduction splint for 4 weeks. At the 18- to 20-year follow-up, the Constant, University of California at Los Angeles Shoulder Rating Scale (UCLA), Larsen, and Simple Shoulder Test (SST) scores were obtained, and clinical and radiographic examinations of both shoulders were performed. Results: Twenty-five of 35 potential patients were examined at the 18- to 20-year follow-up. There were 11 patients with Rockwood type III and 14 with type V dislocations. Delayed surgical treatment for ACJ was used in 2 patients during follow-up: 1 in the operatively treated group and 1 in the nonoperatively treated group. Clinically, ACJs were statistically significantly less prominent or unstable in the operative group than in the nonoperative group (normal/prominent/unstable: 9/4/3 and 0/6/3, respectively; P = .02) and in the operative type III (P = .03) but not type V dislocation groups. In operatively and nonoperatively treated patients, the mean Constant scores were 83 and 85, UCLA scores 25 and 27, Larsen scores 11 and 11, and SST scores 11 and 12 at follow-up, respectively. There were no statistically significant differences in type III and type V dislocations. In the radiographic analysis, the ACJ was wider in the nonoperative than the operative group (8.3 vs 3.4 mm; P = .004), and in the type V dislocations (nonoperative vs operative: 8.5 vs 2.4 mm; P = .007). There was no statistically significant difference between study groups in

  17. Jaw Dislocation as an Unusual Complication of Upper Endoscopy

    Directory of Open Access Journals (Sweden)

    Evan S. Dellon

    2016-05-01

    Full Text Available This case report presents an unusual complication of upper endoscopy, resulting in jaw dislocation. Temporomandibular joint dislocation is commonly reported in association with anesthesia and intubation, but it is not widely recognized as a complication of gastrointestinal endoscopy. This report also reviews the current literature regarding this complication and discusses the potential causes of dislocation, differential diagnoses for jaw pain following endoscopy, and recommendations for prevention.

  18. Migration of a Broken Kirschner Wire after Surgical Treatment of Acromioclavicular Joint Dislocation

    Directory of Open Access Journals (Sweden)

    Sabri Batın

    2016-01-01

    Full Text Available Kirschner wire (K-wire is one of the commonly used implants in orthopaedics practice. Migration of the wire is one of the most frequently reported complications after fixation by the K-wire. In particular, it has been reported that a greater range of motion in the shoulder, negative intrathoracic pressure associated with respiration, gravitational force, and muscular activities may cause migration from the upper extremities. In general, thin and long foreign bodies with smooth surfaces that are localized within the tendon sheath and at an upper extremity can migrate more readily and can reach longer distances. Here, we present a patient with long-term migration of a broken K-wire who underwent fixation for acromioclavicular joint dislocation 5 years ago.

  19. Complete acromioclavicular joint dislocation treated with reconstructed ligament by trapezius muscle fascia and observation of fascial metaplasia.

    Science.gov (United States)

    Wang, Chaoliang; Huang, Sufang; Wang, Yingzhen; Sun, Xuesheng; Zhu, Tao; Li, Qiang; Lin, Chu

    2015-01-01

    We evaluated the long-term clinical results of acute complete acromioclavicular dislocations treated by reconstruction of the acromioclavicular and coracoclavicular ligament using trapezius muscle fascia. Open reduction and internal fixation was performed using the clavicular hook plate in 12 patients with acute complete acromioclavicular joint dislocation, and the acromioclavicular and coracoclavicular ligaments were reconstructed using trapezius muscle fascia. Radiographic evaluations were conducted postoperatively. We evaluated the functional results with constant scoring system and radiological results at the final follow-up visit. The mean Constant score at the final follow-up visit was 91.67 (range, 81 to 100). The results were excellent in eight patients (66.7%) and good in four patients (33.3%). Three patients with scores from 80 to 90 had mild pain during activity, but this did not affect the range of motion of the shoulder. All patients have returned to their preoperative work without any limitations. Compared with the contralateral side, radiography showed anatomical reposition in the vertical plane in all cases. The hook-plate fixation with ligament reconstruction was successful in treating AC dislocations. The acromioclavicular and coracoclavicular ligament were reconstructed by trapezius muscle fascia that keep the distal clavicle stable both vertically and horizontally after type III injuries.

  20. Complete acromioclavicular joint dislocation treated with reconstructed ligament by trapezius muscle fascia and observation of fascial metaplasia

    Directory of Open Access Journals (Sweden)

    Wang Chaoliang

    2015-01-01

    Full Text Available We evaluated the long-term clinical results of acute complete acromioclavicular dislocations treated by reconstruction of the acromioclavicular and coracoclavicular ligament using trapezius muscle fascia. Open reduction and internal fixation was performed using the clavicular hook plate in 12 patients with acute complete acromioclavicular joint dislocation, and the acromioclavicular and coracoclavicular ligaments were reconstructed using trapezius muscle fascia. Radiographic evaluations were conducted postoperatively. We evaluated the functional results with constant scoring system and radiological results at the final follow-up visit. The mean Constant score at the final follow-up visit was 91.67 (range, 81 to 100. The results were excellent in eight patients (66.7% and good in four patients (33.3%. Three patients with scores from 80 to 90 had mild pain during activity, but this did not affect the range of motion of the shoulder. All patients have returned to their preoperative work without any limitations. Compared with the contralateral side, radiography showed anatomical reposition in the vertical plane in all cases. The hook-plate fixation with ligament reconstruction was successful in treating AC dislocations. The acromioclavicular and coracoclavicular ligament were reconstructed by trapezius muscle fascia that keep the distal clavicle stable both vertically and horizontally after type III injuries.

  1. Bipolar Dislocation of the Clavicle: A Report of Two Cases with Different Injury Patterns and a Literature Review

    Directory of Open Access Journals (Sweden)

    Ichiro Okano

    2017-01-01

    Full Text Available Bipolar dislocation of the clavicle is a rare injury that is defined as a concomitant dislocation of the ipsilateral acromioclavicular joint and sternoclavicular joint. This injury is also described as a floating clavicle. Although this injury has been known for nearly two centuries, knowledge about it is limited and the treatment strategy remains controversial. Bipolar dislocation includes several combinations of both joints’ injury types. We reported two patients with bipolar dislocation of the clavicle: one with an anterior dislocation and the other with a posterior dislocation of the sternoclavicular joint. After reviewing the currently available literature, we discussed these cases to highlight the necessity of a specific treatment approach that is modified based on the pattern of each joint’s lesion.

  2. A retrospective comparative study of arthroscopic fixation in acute Rockwood type IV acromioclavicular joint dislocation: single versus double paired Endobutton technique.

    Science.gov (United States)

    Xu, Jian; Liu, Haifeng; Lu, Wei; Li, Dingfu; Zhu, Weimin; Ouyang, Kan; Wu, Bing; Peng, Liangquan; Wang, Daping

    2018-05-24

    Rockwood type IV acromioclavicular joint (ACJ) dislocation is a trauma usually needs surgical treatment. Paired EndoButton technique (PET) is used in treating such condition. However, the effect of using different types of PET (single versus double PET) for fixation remains controversial. This study aims to evaluate and compare the efficacy of single and double PET and to provide a suitable option for the surgeons. We retrospectively reviewed the charts of patients with acute Rockwood type IV ACJ dislocation who had undergone arthroscopic fixation using single or double PET fixation between March 2009 and March 2015. Seventy-eight consecutive patients identified from chart review were picked and were divided into the single and double PET group with 39 cases in each group. The indexes of visual analog scale score (VAS) for pain, the radiographs of the affected shoulder at different time points of the follow-up, the time of return to activities and sports, the constant functional score, and the Karlsson acromioclavicular joint (ACJ) score, were assessed in a minimum of 2 years postoperation. The average coracoclavicular (CC) and acromioclavicular (AC) distances of the affected joints in the double PET group were significantly smaller than those of the single PET group 2 years postoperation (P  0.05). The mean VAS pain score was not significantly different, while significant difference was found for the number and times of cases return to activities and sports, constant functional score, and Karlsson ACJ score (P < 0.05) between the two groups. Therefore, the double PET group has better outcome than the single PET group. Complications including redislocation, button slippage, erosion, or AC joint instability occurred in the single PET group, while the complication in the double PET group was rare. Compared with the single PET, the double PET group achieved better outcome with less complications in arthroscopically treating acute Rockwood type IV ACJ

  3. Lateral subtalar dislocation : Case report and review of the literature

    NARCIS (Netherlands)

    Veltman, Ewout S; Steller, Ernst Ja; Wittich, Philippe; Keizer, Jort

    2016-01-01

    A case of complicated lateral subtalar dislocation is presented and the literature concerning this injury is reviewed. Subtalar joint dislocations are rare and often the result of a high-energy trauma. Complications include avascular necrosis of the talus, infection, posttraumatic osteoarthritis

  4. Reconstruction of displaced acromio-clavicular joint dislocations using a triple suture-cerclage: description of a safe and efficient surgical technique

    Directory of Open Access Journals (Sweden)

    Sandmann Gunther H

    2012-10-01

    Full Text Available Abstract Purpose In this retrospective study we investigated the clinical and radiological outcome after operative treatment of acute Rockwood III-V injuries of the AC-joint using two acromioclavicular (AC cerclages and one coracoclavicular (CC cerclage with resorbable sutures. Methods Between 2007 and 2009 a total of 39 patients fit the inclusion criteria after operative treatment of acute AC joint dislocation. All patients underwent open reduction and anatomic reconstruction of the AC and CC-ligaments using PDS® sutures (Polydioxane, Ethicon, Norderstedt, Germany. Thirty-three patients could be investigated at a mean follow up of 32±9 months (range 24–56 months. Results The mean Constant score was 94.3±7.1 (range 73–100 with an age and gender correlated score of 104.2%±6.9 (88-123%. The DASH score (mean 3.46±6.6 points, the ASES score (94.6±9.7points and the Visual Analogue Scale (mean 0.5±0,6 revealed a good to excellent clinical outcome. The difference in the coracoclavicular distance compared to the contralateral side was Conclusion Open AC joint reconstruction using AC and CC PDS cerclages provides good to excellent clinical results in the majority of cases. However, radiographically, the CC distance increased significantly at final follow up, but neither the amount of re-dislocation nor calcifications of the CC ligaments or osteoarthritis of the AC joint had significant influence on the outcome. Level of evidence Case series, Level IV

  5. Open dislocation of the proximal interphalangeal joint of the little finger subsequent to chronic radial collateral ligament injury: a case report of primary ligament reconstruction with a half-slip of the flexor digitorum superficialis: Case Report.

    Science.gov (United States)

    Wada, Kazuma; Hibino, Naohito; Kondo, Kenji; Yoshioka, Shinji; Terai, Tomoya; Henmi, Tatsuhiko; Sairyo, Koichi

    2015-01-01

    Open dislocation of the proximal interphalangeal (PIP) joint is relatively rare. We report a case of a 32-year-old man who had open dislocation of the PIP joint of the little finger while playing American football. He had a history of chronic radial collateral ligament injury. We reconstructed the radial collateral ligament with a half-slip of the flexor digitorum superficialis tendon.

  6. recurrent traumatic posterior hip dislocation in labral avulsion

    African Journals Online (AJOL)

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

  7. Surgical treatment of dislocated acromioclavicular syndesmolysis remains controversial

    Directory of Open Access Journals (Sweden)

    Slaviša Mihaljevič

    2007-12-01

    Full Text Available Background: Operative treatment of acromioclavicular (AC joint dislocations Allman-Tossy III type is controversial. There are more than 30 types of operative treatments described. At the Department of Traumatology of Celje General and Teaching Hospital (CGTH we operate the AC joint dislocation by the AC joint opened reduction and fixation using two Kirschner wires and additional figure of eight wire loop over the AC joint. The purpose of the analysis is to evaluate the results of acromioclavicular joint complete dislocation Allman-Tossy III type operative treatment.Patients and methods: In the 2-year period from July 1st 1997, to June 31st, 1999, at the Department of Traumatology of CGTH we operatively treated 59 injured persons with the AC joint dislocation. There were 55 men (93 % and 4 women (7 %. The average age was 40 years (from 20 to 72 years. 56 (95 % injured persons had the AC joint injury of Allman-Tossy III type. In first three weeks (early reconstruction we operated 45 injured persons (76.3 %. The applied material was removed after 8 weeks. 47 (79.7 % injured persons were re-examined at least one year after the injury (27 months in average; 14–39 months. The results were evaluated according to University of California at Los Angeles (UCLA scale for the shoulder function evaluation. The impact of factors on a good treatment result was presented by the odds ratio and uni-variant analysis calculation.Results: Out of 47 injured persons re-examined according to the UCLA scale at least one year after the injury there were 17 injured persons (36.2 % rated with an excellent result (UCLA 34– 35, 22 good (46.8 % (UCLA 28–33, 5 satisfactory (10.6 % (UCLA 21–27 and 3 bad (6.4 % (UCLA 0–20. In total we achieved 83 % of excellent and good results. The injured persons age did not significantly affect the treatment result. Complications occurred in 14 (29.8 % injured patients. If no complications were occurred the odds ratio for good

  8. CT findings of traumatic posterior hip dislocation after reduction

    International Nuclear Information System (INIS)

    Moon, Sung Kyoung; Park, Ji Seon; Ryu, Kyung Nam; Jin, Wook; Jin Wook

    2008-01-01

    To evaluate the CT images of reduced hips after posterior hip dislocation and to propose specific diagnostic criteria based on the CT results. We retrospectively reviewed the CT findings on 18 reduced hips from 17 patients with radiographs and clinical histories of traumatic posterior hip dislocations by evaluating 18 corresponding CT scans for joint space asymmetry, intra-articular abnormalities (intra-articular fat obliteration, loose bodies, and joint effusion), changes in posterior soft tissue (capsule, muscles, and adjacent fat), the presence, and location of fractures (acetabulum and femoral head). All 18 hips (100%) showed posterior soft tissue changes. In total, 17 hips (94.4%) had intra-articular abnormalities and 15 hips (83.3%) had joint space asymmetries. In addition, 17 hips (94.4%) had fractures involving the acetabula (15 cases, 88.2%) the femoral head (13 cases, 76.5%), or on both sides (11 cases, 64.7%). The most frequent fracture location was in he posterior wall (13/15, 86.7%) of the acetabulum and in the anterior aspect (10/13, 76.9%) of the femoral head. Patients with a prior history of posterior hip dislocation showed specific CT findings after reduction, suggesting the possibility of previous posterior hip dislocations in patients

  9. [Analysis on the long-term effects of modified double endobutton technique in the treatment of Tossy type III acromioclavicular joint dislocations].

    Science.gov (United States)

    Yan, Rui-Jian; Lu, Jian-Wei; Zhang, Chun

    2014-01-01

    To investigate the long-term clinical effects of modified double Endobutton technique for the treatment of acromioclavicular joint dislocations of Tossy type III. A retrospective study was done in 42 patients with acromioclavicular joint dislocations of Tossy type III treated with modified double Endobutton technique from December 2008 to December 2010. There were 24 males and 18 females, ranging in age from 21 to 56 years old (averaged, 32.5 years old). All the patients were treated with open reduction, coracoclavicular ligament reconstruction using double Endobutton technique, and repair of acromioclavicular ligament. The Karlsson system was used to evaluate therapeutic effects. The distance from coracoid to clavicle was measured to evaluate reduction loss. All the patients were followed up, and the duration ranged from 2.0 to 3.2 years (averaged,2.4 years). According to Karlsson system, 32 patients got an A degree and 10 patients got a B degree at three months post-operatively; 26 patients got an A degree and 16 patients got a B degree at the latest follow-up; 6 patients got an A degree at 3 months after operation lowered to B degree at the latest follow-up. The coracoid-clavicle distance increased from (26.91 +/- 0.91) mm at 3 months after operation to (27.41 +/- 1.10) mm at the latest follow-up. Te patients treated with over-reduction during operation or with heavy physical labour work after operation had obvious widened coracoid-clavicle distance. Bone absorption was found around the plate in most cases, mainly in the clavicular side. Treatment for acromioclavicular joint dislocations of Tossy type III with modified double Endobutton technique has satisfactory early clinical results. But with time passing, loss of reduction and bone absorption around the plate could be observed, and clinical outcomes of some cases downgrade during the long-term follow-up.

  10. Isolated Proximal Tibiofibular Dislocation during Soccer

    Directory of Open Access Journals (Sweden)

    Casey Chiu

    2015-01-01

    Full Text Available Proximal tibiofibular dislocations are rarely encountered in the Emergency Department (ED. We present a case involving a man presenting to the ED with left knee pain after making a sharp left turn on the soccer field. His physical exam was only remarkable for tenderness over the lateral fibular head. His X-rays showed subtle abnormalities of the tibiofibular joint. The dislocation was reduced and the patient was discharged from the ED with orthopedic follow-up.

  11. Bilateral recurrent anterior fracture dislocation of shoulder joint due to grand mal epileptic convulsions

    Directory of Open Access Journals (Sweden)

    Chandrashekara Chowdipalya Maliyappa

    2013-01-01

    Full Text Available Bilateral shoulder dislocation is very much common with convulsions of different etiology. Often, these dislocations are associated with fractures due to violent muscle contractions. The typical lesion is bilateral posterior dislocation or fracture dislocations. The recurrent shoulder dislocations are common with traumatic etiology. The lack of asymmetry of the shoulders is stressed as a potential pitfall in the clinical evaluation of patients with this condition. We present a rare case of bilateral recurrent anterior fracture dislocation of the shoulder sustained due to repetitive episodes of convulsive seizures. Patient was treated by close reductions and immobilization on each episode. In epilepsy although posterior dislocations are common, the rare possibility of bilateral anterior fracture dislocation should be kept in mind. Often these patients are vulnerable for recurrence, similar to traumatic cases.

  12. Unilateral Congenital Knee and Hip Dislocation with Bilateral Clubfoot – A rare Packaging disorder

    Directory of Open Access Journals (Sweden)

    Mukesh Tiwari

    2013-04-01

    Full Text Available ntroduction: Reduced intrauterine space gives rise to ‘packaging disorder’ which may involve joint dislocations or contractures. We present an unique case where mutiple joints were dislocated involving left congenital knee dislocation (CDK, bilateral congenital hip dislocation (CDH and congenital talipes equino varus (CTEVdeformities. Case Report: A preterm baby boy born to mother with diagnosed oligohydramios presented with left CDK bilateral DDH and CTEV. The knee dislocation was treated first with gradual streaching and weekly above knee cast. At 7th week good flexion was achieved at both knees and abduction splint for DDH (using double diaper with ponseti cast for CTEV was done. At one year follow up all joints were reduced and maintained well with baby able to stand with support. Conclusion: Packaging disorders may present with multiple dislocations and deformities. Early intervention with serial casting and manipulation minimises disability and prevents ambulatory problems. In our case there was a good response to manipulation and serial casting. This differs from cases with inherent pathology like arthrogryposis where response to treatment is not so good. Keywords: Congenital genu recurvatum, Develpmental dysplasia hip, CTEV, Clubfoot, serial manipulation, packaging disorders

  13. SURGICAL MANAGEMENT OF TRAUMATIC MANUBRIO-STERNAL DISLOCATION WITH LOCKING COMPRESSION PLATE; A CASE REPORT AND REVIEW OF LITERATURE

    Directory of Open Access Journals (Sweden)

    FAREED AHMED SHAIKH

    2017-05-01

    Full Text Available Background: Manubriosternal joint dislocation as a result of trauma is rare with only few case reports published in literature. Materials that have been used for fixation of displaced manubriosternal joint are steel wires, polydioxanone ropes, and plates with screws. Case: We present a case of manubriosternal dislocation in which fixation was done with locking compression plate. This is a case of 32 years old lady with history of road traffic accident, car ran over her chest. She had bilateral lung contusions with multiple rib fractures on right side and manubriosternal joint dislocation of type-I. Patient was initially stabilized in high dependency unit, and once her contusions got better, she underwent fixation of her manubriosternal dislocation with locking compression plate. Post-operatively she remained pain free and was discharged home. Conclusion: This case is an important addition to literature regarding options that can be used for fixation of manubriosternal joint dislocation.

  14. The epidemiology of shoulder dislocations in Oslo.

    Science.gov (United States)

    Liavaag, S; Svenningsen, S; Reikerås, O; Enger, M; Fjalestad, T; Pripp, A H; Brox, J I

    2011-12-01

    There are few previous studies on the incidence of shoulder dislocation in the general population. The aim of the study was to report the incidence of acute shoulder dislocations in the capital of Norway (Oslo) in 2009. Patients of all ages living in Oslo, sustaining a dislocation of the glenohumeral joint, were identified using electronic diagnosis registers, patient protocols, radiological registers of the hospitals, and the Norwegian Patient Register (NPR). The overall incidence rate was 56.3 [95% confidence interval (CI) 50.2-62.4] per 100,000 person-years, with rates of 82.2 (95% CI 71.7-92.8) and 30.9 (95% CI 24.5-37.3) in men and women, respectively. The incidence of primary dislocations was 26.2 (95% CI 22.1-30.4). The overall incidence of shoulder dislocations in Oslo was higher than previously reported incidences. The incidence of primary dislocations was also higher than that in previously reported studies for the general population but it was close to the incidence reported in Malmø, Sweden. © 2011 John Wiley & Sons A/S.

  15. [New varieties of lateral metatarsophalangeal dislocations of the great toe].

    Science.gov (United States)

    Bousselmame, N; Rachid, K; Lazrak, K; Galuia, F; Taobane, H; Moulay, I

    2001-04-01

    We report seven cases of traumatic dislocation of the great toe, detailing the anatomy, the mechanism of injury and the radiographic diagnosis. We propose an additional classification based on three hereto unreported cases. Between october 1994 and october 1997, we treated seven patients with traumatic dislocation of the first metatarso-phalangeal joint of the great toe. There were six men and one woman, mean age 35 years (range 24 - 44 years). Dislocation was caused by motor vehicle accidents in four cases and by falls in three. Diagnosis was made on anteroposterior, lateral and medial oblique radiographs. According to Jahss' classification, there was one type I and three type IIB dislocations. There was also one open lateral dislocation and two dorsomedial dislocations. Only these dorsomedial dislocations required open reduction, done via a dorsal approach. Mean follow-up was 17.5 months (range 9 - 24 months) in six cases. One patient was lost to follow-up. The outcome was good in six cases and poor in one (dorsomedial dislocation). Dislocation of the first metatarso-phalangeal joint of the great toe is an uncommon injury. In 1980, Jahss reported two cases and reviewed three others described in the literature. He proposed three types of dislocation based on the feasibility of closed reduction (type I, II and IIB). In 1991, Copeland and Kanat reported a unique case in which there was an association of IIA and IIB lesions. They proposed an addition to the classification (type IIC). In 1994, Garcia Mata et al. reported another case which had not been described by Jahss and proposed another addition. All dislocations reported to date have been sagittal dislocations. Pathological alteration of the collateral ligaments has not been previously reported. In our experience, we have seen one case of open lateral dislocation due, at surgical exploration, to medial ligament rupture and two cases of dorsomedial dislocation due, at surgical exploration, to lateral ligament

  16. Atlanto-Occipital Rotatory Dislocation: A Case Report and Systematic Review.

    Science.gov (United States)

    Robles, Luis A; Mundis, Greg M; Cuevas-Solórzano, Abel

    2018-02-01

    Atlanto-occipital rotatory dislocation (AORD) has rarely been reported in the literature; for this reason, the clinicoradiologic characteristics of this injury are not well described. We describe the case of a 67-year-old man who sustained a cervical spine trauma. He reported only neck pain and was neurologically intact. A computed tomography scan showed a rotatory displacement of the atlanto-occipital joints associated with a widened condylar-C1 interval; in addition, magnetic resonance imaging showed injuries to the stabilizing ligaments of this area. A systematic literature review was also performed to identify previous cases of patients with AORD. The patient was treated with craniocervical fixation from occipital to C1, achieving a good outcome. The literature review yielded 9 cases of patients with AORD. Compared with patients with atlanto-occipital dislocation, patients with rotatory dislocations have a less severe degree of displacement of the atlanto-occipital joints and better clinical outcome. Compared with previously classified atlanto-occipital dislocations, AORD is an independent and unique variation. AORD presents with different biomechanical, clinicoradiologic, and prognostic characteristics and represents an important addition to the spectrum of atlanto-occipital dislocation injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Subluxation of the Carpus in Thirteen Horses

    OpenAIRE

    Bailey, J.V.; Barber, S.M.; Fretz, P.B.; Jacobs, K.A.

    1984-01-01

    The records of 13 horses of various breeds with subluxation of the radiocarpal, intercarpal or carpometacarpal joint, or combinations of these were reviewed. Subluxation was most common at the carpometacarpal joint (n = 10) and concomitant fractures of individual carpal bones or metacarpus II and IV were seen (n = 12).

  18. Posterior sternoclavicular dislocation: an American football injury

    DEFF Research Database (Denmark)

    Marker, L B; Klareskov, B

    1996-01-01

    Posterior dislocation of the sternoclavicular joint is uncommon, accounting for less than 0.1% of all dislocations. Since 1824 a little more than 100 cases have been reported, and the majority in the past 20 years. A review of published reports suggests that this injury is seen particularly in co...... in connection with American football. A typical case is described. The importance of this injury is that there is often a delay in diagnosis with potentially serious complications....

  19. MRI after patellar dislocation. Assessment of risk factors and injury to the joint

    International Nuclear Information System (INIS)

    Diederichs, G.

    2013-01-01

    Patellar dislocation is the lateral displacement of the patella from the femoral trochlea. Affected individuals typically have underlying anatomic risk factors of variable magnitude, which, in conjunction with leg rotation, cause the event. Magnetic resonance imaging (MRI) permits straightforward diagnosis of the typical features of recent patellar dislocation: contusion edema of the inferomedial patella and the lateral femoral condyle as well as rupture of the medial patellofemoral ligament. In case of concomitant osteochondral injury, early surgical refixation may be indicated, depending on the size. After a first dislocation, which can damage the capsuloligamentous stabilizers, subjects may sustain further dislocations or even develop chronic patellofemoral instability, depending on the presence and severity of anatomic variants. A wide range of conservative and surgical treatments are available. While a first patellar dislocation is often treated conservatively, surgical strategies after a second dislocation depend on the pattern of injury and the severity of underlying anatomic risk factors. The most relevant predisposing variants are trochlear dysplasia, patella alta, and an abnormal tibial tubercle to trochlear groove distance (TT-TG). The radiologist's report should give a quantitative estimate of both the injuries resulting from dislocation and the underlying anatomic risk factors. An accurate characterization of the individual pathomechanism is crucial for tailoring treatment. (orig.)

  20. Computed tomography of the patellofemoral alignment after arthroscopic reconstruction following patella dislocation

    International Nuclear Information System (INIS)

    Schroeder, R.J.; Hidajat, N.; Maeurer, J.; Felix, R.; Weiler, A.; Hoeher, J.

    2003-01-01

    Purpose: To evaluate the diagnostic impact of different CT-based measurements to analyze the patellofemoral alignment after arthroscopic reconstruction in patients with patella dislocation. Materials and Methods: In 18 patients with dislocation of the patella, CT of the patellofemoral joint was performed after arthroscopic reconstruction. Various methods recommended in the literature were used to analyze the structure and the alignment of the patellofemoral joint with a relaxed quadriceps muscle. Axial CT scans were taken in four different knee flexion angles (15 , 30 , 45 , 60 ). Results: After arthroscopic stabilization in patients with patella dislocation, only the lateral patellofemoral angle (15 and 30 knee flexion) and the congruence angle (15 knee flexion) showed significant differences between the CT-measurements in the normal and the operated group. The differences of the remaining mean values were not significant due to a high standard deviation. With increasing flexion of the knee, the differences between the normal and the dislocation group almost disappeared. Only the lateral patellofemoral angle, the patella tilt and the lateral patella shift revealed differences between the normal and the group with recurrent dislocation in every degree of knee flexion. With increasing knee flexion above 30 and especially at 60 , the majority of the measured values returned to the normal range. Conclusions: For CT-measurements of the patellofemoral joint after arthroscopic stabilization, the patellofemoral angle and the congruence angle seemed to be most useful. The measurements of the patellofemoral joint should be taken in various degrees of knee flexion. (orig.) [de

  1. Surgical treatment of chronic mandibular dislocation--report of a case.

    Science.gov (United States)

    Bakardjiev, Angel G; Atanasov, Dimitar T

    2002-01-01

    Chronic dislocation of the temporomandibular jaw (TMJ) can result from lax joint ligaments and parafunctioning joints; it can also be a consequence of a systemic connective tissue disorder. The authors report a case of hypermobile joint syndrome in combination with mitral valve prolapse. The case was managed by osteosynthesis using modified titanium plate.

  2. [Case-control study on shoulder pain caused by hook palte for the treatment of acromioclavicular joint dislocation].

    Science.gov (United States)

    Yang, Ying-guo; Cai, Xiao-bing; Wang, Xiao-min; Zhu, Yong-gan; Pan, He-yong

    2015-06-01

    To explore causes of shoulder pain and propose prevention measures in treating acromioclavicular joint dislocation. From January 2005 to January 2013, 86 patients with acromioclavicular joint dislocation (Tossy III) were treated with hook plate fixation, and were divided into two groups. Bsaed on recovery of shoulder function mostly, the patients who suffered from rest pain, motion pain were named as shoulder pain group, while the patients without pain were named as painless group. In shoulder pain group, there were 21 cases including 15 males and and 6 females ranging the age from 22 to 62 years old with an average of (40.6±11.2) years old. There were 8 cases were on the left side and 13 cases were on the right side. In painless group, there were 65 cases including 36 males and and 29 females ranging the age from 19 to 65 years old with an average of (40.0±11.3) years old. There were 33 cases were on the left side and 32 cases were on the right side. The time from injury to operation ranged from 3 h to 8 d with an average of 34.6 h. Shoulder function of all patients were normal before injuried. Postoperative pain, activity of daily living (ADL), range of motion, deltoid muscle strength were compared. Anteflexion,rear protraction, abduction and upthrow of shoulder joint were also compared. Postoperative complications between two groups were observed and compared. All patients were followed up from 12 to 48 months with an average of 18.5 months. Constant-Murley score were used to evaluate clinical efficacy at the least following up, and 13 cases got an excellent results, 5 moderate, 2 good and 1 poor in shoulder pain group ; while 61 cases were obtained excellent results, 3 moderate and 1 good in painless group. There were significantly differences between two groups in Constant-Murley score and activity of shoulder joint (Pacromioclavicular arthritis. Chosing individual clavicular hook plate, fulfilling anatomic reset, paying attention to the repair of articular

  3. Irreducible Traumatic Posterior Shoulder Dislocation

    Directory of Open Access Journals (Sweden)

    Blake Collier

    2017-01-01

    Full Text Available History of present illness: A 22-year-old male presented to the Emergency Department complaining of right shoulder pain after a motocross accident. He was traveling at approximately 10 mph around a turn when he lost control and was thrown over the handlebars, landing directly on his right shoulder. On arrival, he was holding his arm in adduction and internal rotation. An area of swelling was noted over his anterior shoulder. He was unable to abduct his shoulder. No humeral gapping was noted. He had normal neuro-vascular status distal to the injury. Significant findings: Radiographs demonstrated posterior displacement of the humeral head on the “Y” view (see white arrow and widening of the glenohumeral joint space on anterior-posterior view (see red arrow. The findings were consistent with posterior dislocation and a Hill-Sachs type deformity. Sedation was performed and reduction was attempted using external rotation, traction counter-traction. An immediate “pop” was felt during the procedure. Post-procedure radiographs revealed a persistent posterior subluxation with interlocking at posterior glenoid. CT revealed posterior dislocation with acute depressed impaction deformity medial to the biceps groove with the humeral head perched on the posterior glenoid, interlocked at reverse Hill-Sachs deformity (see blue arrow. Discussion: Posterior shoulder dislocations are rare and represent only 2% of all shoulder dislocations. Posterior shoulder dislocations are missed on initial diagnosis in more than 60% of cases.1 Posterior shoulder dislocations result from axial loading of the adducted and internally rotated shoulder, violent muscle contractions (resulting from seizures or electrocution, a direct posterior force applied to the anterior shoulder.1 Physical findings include decreased anterior prominence of the humeral head, increased palpable posterior prominence of the humeral head below the acromion, increased palpable prominence of the

  4. Transarticular fixation by hook plate versus coracoclavicular stabilization by single multistrand titanium cable for acute Rockwood grade-V acromioclavicular joint dislocation: a case-control study.

    Science.gov (United States)

    Gao, You-Shui; Zhang, Yue-Lei; Ai, Zi-Sheng; Sun, Yu-Qiang; Zhang, Chang-Qing; Zhang, Wei

    2015-11-19

    Hook plate (HP) is popularly used for acute and severely displaced acromioclavicular (AC) dislocations. However, subacromial impingement and acromion osteolysis induced by transarticular fixation are notorious. The current case-control study was to compare transarticular fixation by HP to coracoclavicular (CC) stabilization by single multistrand titanium cable (MSTC). Between January 2006 and August 2009, 24 patients with acute AC dislocations were surgically treated by open reduction and transarticular fixation with HP. These patients were matched to a series of 24 patients, who were managed by CC stabilization with MSTC in the same period. All AC dislocations were graded as Rockwood type V. Implant was removed 8-12 months after the primary operation in all patients, and 12 months at least were needed to assess the maintenance of AC joint. Functional results were evaluated before implant removal as well as in the last follow-up based on Constant-Murley criteria. There were no differences of demographic data including age, dominant gender and side, injury-to-surgery interval, operation time and follow-up period. In terms of functionality, Constant score was 95.8 ± 4.1 in MSTC group, while 76.7 ± 8.0 in HP group before implant removal (P acromioclavicular joint presented in 16 patients (66.7%) in patients treated by HP, while it was found in only 3 patients (12.5%) treated by MSTC (P acromioclavicular dislocation both before and after removal of the implant. Hardware removal is of great benefits for functional improvement in patients treated by HP.

  5. Imageological measurement of the sternoclavicular joint and its clinical application.

    Science.gov (United States)

    Li, Ming; Wang, Bo; Zhang, Qi; Chen, Wei; Li, Zhi-Yong; Qin, Shi-Ji; Zhang, Ying-Ze

    2012-01-01

    Dislocation of the sternoclavicular joint is rare. However, posterior dislocation compressing important structures in the mediastinum may be fatal. Early diagnosis and prompt therapy of sternoclavicular joint dislocation are important. Computed tomography (CT) is an optimal means to investigate sternoclavicular joint anatomy; however, there are few reports on the imageological anatomical features of the sternoclavicular joint. The study investigated imageological anatomical features, and a new plate was devised according to these data to treat sternoclavicular joint dislocation. Fifty-three healthy Chinese volunteers examined with chest CT were included in the study. The coronal, sagittal, and axial images of the sternoclavicular region were reconstructed. The sternal head diameter in the inferolateral-to-superomedial direction, length of the clavicular notch, and angle between the clavicular notch and sternum were measured on coronal images. The angle between the presternum and trunk was measured on sagittal images. The following dimensions were measured on axial images: anteroposterior dimensions of the sternal head, clavicular notch, and presternum; width of the sternoclavicular joint; distance between bilateral clavicles; and minimal distance from the presternum to the underlying structures in the thoracic cavity. A new plate was designed according to the above data and was used to repair six sternoclavicular joint dislocations. All cases were followed up with a range of 9 to 12 months. The proximal clavicle is higher than the presternum in a horizontal position. On axial images, the anteroposterior dimension of the sternal head was longer than the presternum, and the center region of the presternum was thinner than the edges. The left sternoclavicular joint space was (0.82 ± 0.21) cm, and the right was (0.87 ± 0.22) cm. Among the structures behind the sternum, the left bilateral innominate vein ran nearest to the presternum. The distance from the anterior

  6. Interferometric SAR and land deformation. Analysis using the dislocation model; Interferometric SAR to chikaku hendo. Dislocation model wo mochiita kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Matsushima, J; Otaki, T; Tanaka, A; Miyazaki, Y [Geological Survey of Japan, Tsukuba (Japan)

    1996-05-01

    The diastrophism by the earthquake-induced dislocation is investigated by interferometry (INSAR) which represents the diastrophism by the interference fringes of equiphase difference lines. A joint research group at Geographical Survey Institute and National Space Development Agency showed the diastrophism in the vicinity of the ground surfaces before and after the Hyogoken Nanbu Earthquake by the INSAR interference images in 1995. This paper discusses the effects of observation in the vision line direction from the satellite and dislocation parameters on the interference images. The dislocation model uses a slanted rectangular model in a semi-infinite medium, to calculate static displacements and strain distributions at the ground surface, when dislocation changes. It is found that the INSAR interference images, detecting displacements in the vision line direction from the satellite, significantly change as the vision line direction changes, and that the actual displacement cannot be given by the images alone. This paper also shows sensitivity of the interference images to the dislocation parameters. 3 refs., 9 figs., 1 tab.

  7. Plain film diagnostic of the acromio-clavicular dislocation

    International Nuclear Information System (INIS)

    Vogel, H.; Thomae, J.; Jungbluth, K.H.; Hamburg Univ.

    1980-01-01

    The distance between the clavicula and the acromion, between the clavicula and the processus coracoideus and the step height between the acromion and the clavicula arch were measured on roentgen films. Evaluated were plain films of the shoulder and of the chest. 64 patients with dislocation of the acromio-clavicular joint were compared to patients without shoulder lesion. The comparance of both groups showed that measures exceeding the upper limits of the group without lesions are highly suggestive for acromio-clavicular dislocation. If one defines an acromio-clavicular dislocation as proved when two of the measured three distances exceed the upper limit, then an acromio-clavicular dislocation could be seen in 36% of the analysed cases on plain films of the shoulder and in 56% on plain chest films. (orig.) [de

  8. Axillary artery injury secondary to inferior shoulder dislocation.

    Science.gov (United States)

    Plaga, Brad R; Looby, Peter; Feldhaus, Steven J; Kreutzmann, Karl; Babb, Aaron

    2010-11-01

    Dislocation injuries of the glenohumeral joint are common in the general public and generally are corrected without complication. One serious complication with shoulder dislocations, or the subsequent reduction, is a lesion to the axillary artery. This specific complication is most frequently seen in the elderly population, where vascular structures have become less flexible. Also, these injuries are most common in association with anterior dislocations of the shoulder. To bring awareness to the possibility of axillary artery injury with inferior dislocation of the shoulder, the treatment options, and a review. We report a 15-year-old male athlete who inferiorly dislocated his shoulder during wrestling practice. The injury was reduced at the scene with manual traction and the patient was transferred to our clinic for evaluation. The patient was determined to have a pseudoaneurysm of the axillary artery, and the history and treatment of the illness are presented. Axillary artery injuries secondary to shoulder dislocations are rare, especially in the young athlete, and proper recognition and treatment offer patients a full recovery. Copyright © 2010. Published by Elsevier Inc.

  9. Irreducible Fifth Metatarsophalangeal Joint after Car Crush Injury

    Science.gov (United States)

    Turkmensoy, Fatih; Erinc, Samet; Ergin, Omer Naci; Ozkan, Korhan; Kemah, Bahattin

    2015-01-01

    Metatarsophalangeal joint dislocations are uncommon injuries. Herein, an irreducible dislocation of fifth metatarsophalangeal joint with fractures on the second, third, and fourth metatarsal head was reported. Joint reduction could not be achieved which necessitated open reduction. Six months after surgery the patient was walking and doing his daily activities without any complaints. He had returned to his pretrauma functional level. PMID:25861501

  10. Irreducible Fifth Metatarsophalangeal Joint after Car Crush Injury

    Directory of Open Access Journals (Sweden)

    Fatih Turkmensoy

    2015-01-01

    Full Text Available Metatarsophalangeal joint dislocations are uncommon injuries. Herein, an irreducible dislocation of fifth metatarsophalangeal joint with fractures on the second, third, and fourth metatarsal head was reported. Joint reduction could not be achieved which necessitated open reduction. Six months after surgery the patient was walking and doing his daily activities without any complaints. He had returned to his pretrauma functional level.

  11. Complications after arthroscopic coracoclavicular reconstruction using a single adjustable-loop-length suspensory fixation device in acute acromioclavicular joint dislocation.

    Science.gov (United States)

    Shin, Sang-Jin; Kim, Nam-Ki

    2015-05-01

    The purpose of this study was to evaluate clinical and radiological outcomes after arthroscopically assisted coracoclavicular (CC) fixation using a single adjustable-loop-length suspensory fixation device for acute acromioclavicular dislocation and to report intraoperative and postoperative complications. Eighteen consecutive patients with acute acromioclavicular dislocation underwent arthroscopically assisted CC fixation using a single TightRope (Arthrex, Naples, FL). Using the Rockwood classification, 3 patients had grade III dislocations, one patient had a grade IV dislocation, and 14 patients had grade V dislocations. The preoperative CC distance of the injured shoulder was 16.1 ± 2.7 mm (range, 11.2 to 21.0 mm), and it increased by 99% ± 36% (range, 17% to 153%) on average compared with the contralateral shoulder. The average CC distance was 10.5 ± 2.5 mm (range, 7.7 to 15.5 mm), and it increased by 30% ± 30% (range, -9.4% to 90%) at the final follow-up. Compared with immediate postoperative radiographs, the CC distance was maintained in 12 patients, increased between 50% and 100% in 4 patients, and increased more than 100% in 2 patients at final follow-up. However, there was no statistical difference in Constant scores between 6 patients with reduction loss (95.6 ± 4.5) and 12 patients with reduction maintenance (98.4 ± 2.5; P = .17). Perioperative complications occurred in 8 patients, including one case of acromioclavicular arthritis, one case of delayed distal clavicular fracture at the clavicular hole of the device, 3 cases of clavicular or coracoid button failures, and 3 cases of clavicular bony erosion. Satisfactory clinical outcomes were obtained after CC fixation using the single adjustable-loop-length suspensory fixation device for acute acromioclavicular joint dislocation. However, CC fixation failure of greater than 50% of the unaffected side in radiological examinations occurred in 33% of the patients within 3 months after the operation

  12. Spinal kirschner wire migration after surgical treatment of clavicular fracture or acromioclavicular joint dislocation: Report of a case and meta-analysis

    Directory of Open Access Journals (Sweden)

    Hermann Adonis N'da

    2018-06-01

    Full Text Available Kirschner wire is the most used device for clavicular and acromioclavicular joint dislocation fixation. Although wire migrations have been extensively reported, spinal migrations remain rare. Moreover, the mechanism of migration is still elusive. The aim of the present paper is to describe a single case of cervical spine migration of a K-wire followed by meta-analysis. Twelve cases of spinal K-wire have been reported in the last 20years, with less than 2 cases per year. Clavicular fixation was the main initial procedure with 66.67% of cases. The average time between surgery and migration was 25.5months. C7-T1 and T2-T3 were the prominent level of migration with each 33.33% of cases, where the migration was transversal in 72.73% of cases. The neural foramen was the most penetrating site of the K-wire in the spine (75% of cases. In all cases the wire was removed via direct access surgery by gentle pulling out along its axis under view control. The greater range of motion in the shoulder seems to be the main mechanism of all kinds of migrations. Keywords: Acromioclavicular joint dislocation, Clavicular fracture, Kirschner wire migration

  13. Elbow joint stability in relation to forced external rotation

    DEFF Research Database (Denmark)

    Deutch, S.R.; Jensen, S.L.; Olsen, B.S.

    2003-01-01

    The objective of this study was to evaluate the osseous constraint related to forced forearm external rotation as the initial stage in a posterior elbow dislocation. Six joint specimens without soft tissues were examined in a joint analysis system developed for simulation of dislocation. The osse......The objective of this study was to evaluate the osseous constraint related to forced forearm external rotation as the initial stage in a posterior elbow dislocation. Six joint specimens without soft tissues were examined in a joint analysis system developed for simulation of dislocation...... external forearm rotation until the point of maximal torque decreased from a maximum in full extension to a minimum at 30 degrees of elbow flexion (P =.03). The elbow in a slightly flexed position, varus stress, and forearm external rotation trauma might be the important biomechanical factors...

  14. Dislocation structure evolution in 304L stainless steel and weld joint during cyclic plastic deformation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hao; Jing, Hongyang; Zhao, Lei; Han, Yongdian; Lv, Xiaoqing [School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300072 (China); Xu, Lianyong, E-mail: xulianyong@tju.edu.cn [School of Materials Science and Engineering, Tianjin University, Tianjin 300072 (China); Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300072 (China)

    2017-04-06

    Dislocation structures and their evolution of 304L stainless steel and weld metal made with ER308L stainless steel welding wire subjected to uniaxial symmetric strain-controlled loading and stress-controlled ratcheting loading were observed by transmission electron microscopy (TEM). The correlation between the cyclic response and the dislocation structure has been studied. The experiment results show that the cyclic behaviour of base metal and weld metal are different. The cyclic behaviour of the base metal consists of primary hardening, slight softening and secondary hardening, while the weld metal shows a short hardening within several cycles followed by the cyclic softening behaviour. The microscopic observations indicate that in base metal, the dislocation structures evolve from low density patterns to those with higher dislocation density during both strain cycling and ratcheting deformation. However, the dislocation structures of weld metal change oppositely form initial complicated structures to simple patterns and the dislocation density gradually decrease. The dislocation evolution presented during the strain cycling and ratcheting deformation is summarized, which can qualitatively explain the cyclic behaviour and the uniaxial ratcheting behaviour of two materials. Moreover, the dislocation evolution in the two types of tests is compared, which shows that the mean stress has an effect on the rate of dislocation evolution during the cyclic loading.

  15. Unreduced elbow dislocation treated by Ilizarov method: A case report

    Directory of Open Access Journals (Sweden)

    Jovanović Vesna

    2010-01-01

    Full Text Available Introduction. Unreduced elbow dislocation is every elbow dislocation older than one week. It may be treated non-operatively (with prereduction traction or surgically. The treatment goals are: to reduce pain, to establish joint stability and movements. There are a lot of techniques described in literature, series are relatively small, mostly case reports. Multicentric studies have not been done. That is why there are no precisely defined therapeutic protocols. Every contribution in the field is valuable. Case Outline. A 43-year-old patient was admitted for the treatment of a three-month old unreduced elbow dislocation. Treatment has been done by Ilizarov method, using the reduction mechanism. The reduction process lasted two weeks. The Ilizarov device was removed two months after the operation, then physical therapy was started. Normal anatomical and functional findings were established five months following the operation. Conclusion. The presented method of treatment has been found as very useful, having in mind that it may solve two problems: difficult reduction and redislocation. Reduction may be done without the joint opening, step by step; retention of the reduced joint may be easily done. Physical therapy may be started without Ilizarov device removal, movements of flexion and extension may be improved without any lateral instability. There is no iatrogenic intraarticular damage, so there are no secondary joint degeneration, pains and invalidity.

  16. Congenital dislocation of knee with ipsilateral developmental dysplasia of hip

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    Sameer Kakar

    2017-01-01

    Full Text Available We present a rare case of a newborn having congenital knee dislocation (CDK with ipsilateral developmental dysplasia of hip (DDH. This case report shows how abnormal intrauterine pressure leads to dislocation of various joints in utero. We managed this conservatively with Pavlik Harness for DDH and serial corrective casting with manipulation for CDK with a satisfactory result after follow-up of 6 months.

  17. The relationship between chronic type III acromioclavicular joint dislocation and cervical spine pain

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    Vestri Anna R

    2009-12-01

    Full Text Available Abstract Background This study was aimed at evaluating whether or not patients with chronic type III acromioclavicular dislocation develop cervical spine pain and degenerative changes more frequently than normal subjects. Methods The cervical spine of 34 patients with chronic type III AC dislocation was radiographically evaluated. Osteophytosis presence was registered and the narrowing of the intervertebral disc and cervical lordosis were evaluated. Subjective cervical symptoms were investigated using the Northwick Park Neck Pain Questionnaire (NPQ. One-hundred healthy volunteers were recruited as a control group. Results The rate and distribution of osteophytosis and narrowed intervertebral disc were similar in both of the groups. Patients with chronic AC dislocation had a lower value of cervical lordosis. NPQ score was 17.3% in patients with AC separation (100% = the worst result and 2.2% in the control group (p Conclusions Our study shows that chronic type III AC dislocation does not interfere with osteophytes formation or intervertebral disc narrowing, but that it may predispose cervical hypolordosis. The higher average NPQ values were observed in patients with chronic AC dislocation, especially in those that developed cervical hypolordosis.

  18. ARTHROSCOPIC TREATMENT OF ACROMIOCLAVICULAR JOINT DISLOCATION BY TIGHT ROPE TECHNIQUE (ARTHREX®)

    Science.gov (United States)

    GÓmez Vieira, Luis Alfredo; Visco, Adalberto; Daneu Fernandes, Luis Filipe; GÓmez Cordero, Nicolas Gerardo

    2015-01-01

    Presenting the arthroscopic treatment by Tight Rope - Arthrex® system for acute acromioclavicular dislocation and to evaluate results obtained with this procedure. Methods: Between August 2006 and May 2007, 10 shoulders of 10 patients with acute acromioclavicular dislocation were submitted to arthroscopic repair using the Tight Rope - Arthrex® system. Minimum follow-up was 12 months, with a mean of 15 months. Age ranged from 26 to 42, mean 34 years. All patients were male. Radiology evaluation was made by trauma series x-ray. The patients were assisted in the first month weekly and after three months after the procedure. Clinical evaluation was based on the University of California at Los Angeles (UCLA) criteria. Results: All patients were satisfied after the arthroscopic procedure and the mean UCLA score was 32,5. Conclusion: The arthroscopic treatment by Tight Rope – Arthrex® system for acute acromioclavicular dislocation showed to be an efficient technique. PMID:26998453

  19. Functional treatment versus plaster for simple elbow dislocations (FuncSiE: a randomized trial

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    Verleisdonk Egbert JMM

    2010-11-01

    Full Text Available Abstract Background Elbow dislocations can be classified as simple or complex. Simple dislocations are characterized by the absence of fractures, while complex dislocations are associated with fractures. After reduction of a simple dislocation, treatment options include immobilization in a static plaster for different periods of time or so-called functional treatment. Functional treatment is characterized by early active motion within the limits of pain with or without the use of a sling or hinged brace. Theoretically, functional treatment should prevent stiffness without introducing increased joint instability. The primary aim of this randomized controlled trial is to compare early functional treatment versus plaster immobilization following simple dislocations of the elbow. Methods/Design The design of the study will be a multicenter randomized controlled trial of 100 patients who have sustained a simple elbow dislocation. After reduction of the dislocation, patients are randomized between a pressure bandage for 5-7 days and early functional treatment or a plaster in 90 degrees flexion, neutral position for pro-supination for a period of three weeks. In the functional group, treatment is started with early active motion within the limits of pain. Function, pain, and radiographic recovery will be evaluated at regular intervals over the subsequent 12 months. The primary outcome measure is the Quick Disabilities of the Arm, Shoulder, and Hand score. The secondary outcome measures are the Mayo Elbow Performance Index, Oxford elbow score, pain level at both sides, range of motion of the elbow joint at both sides, rate of secondary interventions and complication rates in both groups (secondary dislocation, instability, relaxation, health-related quality of life (Short-Form 36 and EuroQol-5D, radiographic appearance of the elbow joint (degenerative changes and heterotopic ossifications, costs, and cost-effectiveness. Discussion The successful

  20. Managing dislocations of the hip, knee, and ankle in the emergency department

    Science.gov (United States)

    Arnold, Caylyne; Fayos, Zane; Bruner, David; Arnold, Dylan

    2017-12-01

    Dislocation of the major joints of the lower extremities--hip, knee, and ankle--can occur due to motor-vehicle crashes, falls, and sports injuries. Hip dislocations are the most common, and they require emergent management to prevent avascular necrosis of the femoral head. Knee dislocations are uncommon but potentially dangerous injuries that can result in amputation due to the potential for missed secondary injury, especially if they are reduced spontaneously. Isolated ankle dislocations are relatively rare, as most ankle dislocations involve an associated fracture. This review presents an algorithmic approach to management that ensures that pain relief, imaging, reduction, vascular monitoring, and emergent orthopedic consultation are carried out in a timely fashion. Copyright © 2017 EB Medicine. All rights reserved.

  1. Case report

    African Journals Online (AJOL)

    abp

    successful closed reduction: review of the literature and anatomic reevaluation. J Hand Surg. 1986;11(4):521-525. PubMed | Google Scholar. 2. Buzby BF .Palmar carpometacarpal dislocation of the fifth metacarpal. Ann Surg. 1934;100:555-557.

  2. Benign joint hypermobility syndrome in soldiers; what is the effect of military training courses on associated joint instabilities?

    Directory of Open Access Journals (Sweden)

    Kamran Azma

    2014-01-01

    Full Text Available Background: Hypermobile joints are joints with beyond normal range of motion and may be associated with joint derangements. This study aimed to evaluate the prevalence of benign joint hypermobility syndrome (BJHS among soldiers and effect of training courses on related joint instabilities. Materials and Methods: In a prospective cohort study on 721 soldiers of Iran Army in Isfahan in 2013 the prevalence of joint hypermobility was obtained by using Beighton criteria. Soldiers divided in two groups of healthy and suffered based on their scores. The prevalence of ankle sprain, shoulder and temporomandibular joint (TMJ dislocations identified before beginning service by history-taking and reviewing paraclinical documents. After 3 months of military training, a recent occurrence of mentioned diseases was revaluated in two groups. The collected data were analyzed using SPSS-20 software using Independent-T and Chi-square tests. Results: The frequency of BJHS before military training was 29.4%. After passing military training period, the incidence of ankle sprain was significantly higher in suffered group achieving the minimum Beighton score (BS of 4 (4.3%, P = 0.03, 5 (5.5%, P = 0.005 and also 6 out of 9 (6.5%, P = 0.01. The incidence of TMJ dislocation was not significantly different based on a minimum score of 4, while it was higher in suffered group when considering the score of 5 (2.1% and 6 (2.6% for discrimination of two groups (P = 0.03. There was no significant difference between two groups in case of shoulder dislocation anyway. Conclusion: Military training can increase the incidence of ankle sprains and TMJ dislocations in hypermobility persons with higher BS in comparison with healthy people. Therefore, screening of joint hypermobility may be useful in identifying individuals at increased risk for joint instabilities.

  3. Primary ankle arthrodesis for neglected open weber B ankle fracture dislocation.

    LENUS (Irish Health Repository)

    Thomason, Katherine

    2014-07-01

    Primary ankle arthrodesis used to treat a neglected open ankle fracture dislocation is a unique decision. A 63-year-old man presented to the emergency department with a 5-day-old open fracture dislocation of his right ankle. After thorough soft tissue debridement, primary arthrodesis of the tibiotalar joint was performed using initial Kirschner wire fixation and an external fixator. Definitive soft tissue coverage was later achieved using a latissimus dorsi free flap. The fusion was consolidated to salvage the limb from amputation. The use of primary arthrodesis to treat a compound ankle fracture dislocation has not been previously described.

  4. Diagnosis of Ehlers-Danlos syndrome after a first shoulder dislocation.

    Science.gov (United States)

    Nourissat, Geoffroy; Vigan, Marie; Hamonet, Claude; Doursounian, Levon; Deranlot, Julien

    2018-01-01

    Shoulder dislocation is often the first symptom of Ehlers-Danlos syndrome (EDS). Whether it occurs in early-onset EDS is unknown. In most cases, surgical failure leads to the diagnosis. We aimed to determine whether clinical symptoms can signal the presence of EDS at a first dislocation. In this retrospective study, we analyzed clinical and radiologic data for 27 patients with EDS and shoulder instability and a control population of 40 consecutive non-EDS patients undergoing surgery for an unstable shoulder. Data were collected on gender, age, single or bilateral disease, general hyperlaxity, shoulder hyperlaxity, number of dislocations or subluxations, nontraumatic onset, and pain specificity. Nerve and vascular injuries, joint disorders, and family history were recorded, and radiologic data were reported. Age 85°) did not differ between the groups. After a first dislocation in a young girl with global hyperlaxity but not necessarily shoulder hyperlaxity, painless atraumatic dislocation with pain after reduction can suggest EDS. Copyright © 2018. Published by Elsevier Inc.

  5. Biomechanical evaluation of the impact of various facet joint lesions on the primary stability of anterior plate fixation in cervical dislocation injuries: a cadaver study: Laboratory investigation.

    Science.gov (United States)

    Oberkircher, Ludwig; Born, Sebastian; Struewer, Johannes; Bliemel, Christopher; Buecking, Benjamin; Wack, Christina; Bergmann, Martin; Ruchholtz, Steffen; Krüger, Antonio

    2014-10-01

    Injuries of the subaxial cervical spine including facet joints and posterior ligaments are common. Potential surgical treatments consist of anterior, posterior, or anterior-posterior fixation. Because each approach has its advantages and disadvantages, the best treatment is debated. This biomechanical cadaver study compared the effect of different facet joint injuries on primary stability following anterior plate fixation. Fractures and plate fixation were performed on 15 fresh-frozen intact cervical spines (C3-T1). To simulate a translation-rotation injury in all groups, complete ligament rupture and facet dislocation were simulated by dissecting the entire posterior and anterior ligament complex between C-4 and C-5. In the first group, the facet joints were left intact. In the second group, one facet joint between C-4 and C-5 was removed and the other side was left intact. In the third group, both facet joints between C-4 and C-5 were removed. The authors next performed single-level anterior discectomy and interbody grafting using bone material from the respective thoracic vertebral bodies. An anterior cervical locking plate was used for fixation. Continuous loading was performed using a servohydraulic test bench at 2 N/sec. The mean load failure was measured when the implant failed. In the group in which both facet joints were intact, the mean load failure was 174.6 ± 46.93 N. The mean load failure in the second group where only one facet joint was removed was 127.8 ± 22.83 N. In the group in which both facet joints were removed, the mean load failure was 73.42 ± 32.51 N. There was a significant difference between the first group (both facet joints intact) and the third group (both facet joints removed) (p cadaver study, primary stability of anterior plate fixation for dislocation injuries of the subaxial cervical spine was dependent on the presence of the facet joints. If the bone in one or both facet joints is damaged in the clinical setting, anterior plate

  6. [Resection of a carpal bone row in a Pustertaler Sprinze cow with chronic purulent arthritis of the carpal joint and osteomyelitis].

    Science.gov (United States)

    Kofler, J; Peterbauer, C

    2014-01-01

    This case report describes the clinical and radiographic findings and the surgical treatment of a serofibrinous arthritis of the antebrachiocarpal joint and of a chronic purulent arthritis of the intercarpal and carpometacarpal joints with osteomyelitis of the distal carpal bones and subchondral osteomyelitis of the proximal metacarpal bones in a cow of the breed "Pustertaler Sprinze". The therapy comprised an arthrotomy of both joint spaces and the resection of the distal row of the carpal bones. The right forelimb had been immobilised for 70 days by a full limb cast. After this period, radiographs revealed an ob- vious ankylosis of the carpal joint, and the cow showed only a slight lameness. Six years postoperatively this cow was still in the herd and had produced six calves.

  7. Managing dislocations of the hip, knee, and ankle in the emergency department [digest].

    Science.gov (United States)

    Arnold, Caylyne; Fayos, Zane; Bruner, David; Arnold, Dylan; Gupta, Nachi; Nusbaum, Jeffrey

    2017-12-20

    Dislocation of the major joints of the lower extremities--hip, knee, and ankle--can occur due to motor-vehicle crashes, falls, and sports injuries. Hip dislocations are the most common, and they require emergent management to prevent avascular necrosis of the femoral head. Knee dislocations are uncommon but potentially dangerous injuries that can result in amputation due to the potential for missed secondary injury, especially if they are reduced spontaneously. Isolated ankle dislocations are relatively rare, as most ankle dislocations involve an associated fracture. This review presents an algorithmic approach to management that ensures that pain relief, imaging, reduction, vascular monitoring, and emergent orthopedic consultation are carried out in a timely fashion. [Points & Pearls is a digest of Emergency Medicine Practice.].

  8. Dubious space for Artelon joint resurfacing for basal thumb (trapeziometacarpal joint) osteoarthritis. A systematic review.

    Science.gov (United States)

    Smeraglia, Francesco; Mariconda, Massimo; Balato, Giovanni; Di Donato, Sigismondo Luca; Criscuolo, Giovanni; Maffulli, Nicola

    2018-04-06

    Trapeziometacarpal arthritis is a common and disabling condition. There is no evidence in the literature of superiority of one surgical procedure over others. Several prosthetic implants have been introduced to preserve joint mobility. We searched the on Medline (PubMed), Web of Science and Scopus databases using the combined keywords 'artelon', 'thumb', 'carpometacarpal', 'trapeziometacarpal' and 'rhizoarthrosis'; 11 studies were identified. The use of Artelon implant is not recommended because of its high revision rate and worse outcomes compared to conventional techniques. Inert materials subjected to compressive and shearing forces could produce debris and subsequent inflammatory response. There is debate in the published scientific literature regarding the role of preoperative antibiotic profilaxis and post-surgery inflammatory response. Standard techniques such as trapeziectomy alone or combined with interposition or suspensionplasty offer effective treatment for thumb basal joint arthritis. Several prosthetic implants show promising results in terms of pain relief and functional request, but there is a need of long-term randomized controlled trials to demonstrate their equivalence, and eventually superiority, compared to standard techniques.

  9. Radial head button holing: a cause of irreducible anterior radial head dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Su-Mi; Chai, Jee Won; You, Ja Yeon; Park, Jina [Seoul National University Seoul Metropolitan Government Boramae Medical Center, Department of Radiology, Seoul (Korea, Republic of); Bae, Kee Jeong [Seoul National University Seoul Metropolitan Government Boramae Medical Center, Department of Orthopedic Surgery, Seoul (Korea, Republic of)

    2016-10-15

    ''Buttonholing'' of the radial head through the anterior joint capsule is a known cause of irreducible anterior radial head dislocation associated with Monteggia injuries in pediatric patients. To the best of our knowledge, no report has described an injury consisting of buttonholing of the radial head through the annular ligament and a simultaneous radial head fracture in an adolescent. In the present case, the radiographic findings were a radial head fracture with anterior dislocation and lack of the anterior fat pad sign. Magnetic resonance imaging (MRI) clearly demonstrated anterior dislocation of the fractured radial head through the torn annular ligament. The anterior joint capsule and proximal portion of the annular ligament were interposed between the radial head and capitellum, preventing closed reduction of the radial head. Familiarity with this condition and imaging findings will aid clinicians to make a proper diagnosis and fast decision to perform an open reduction. (orig.)

  10. Superolateral dislocation of an intact mandibular condyle into the temporal fossa: case report and literature review.

    Science.gov (United States)

    Sharma, Divashree; Khasgiwala, Ankit; Maheshwari, Bharat; Singh, Charanpreet; Shakya, Neelam

    2017-02-01

    Temporomandibular joint dislocation refers to the dislodgement of mandibular condyle from the glenoid fossa. Anterior and anteromedial dislocations of the mandibular condyle are frequently reported in the literature, but superolateral dislocation is a rare presentation. This report outlines a case of superolateral dislocation of an intact mandibular condyle that occurred in conjunction with an ipsilateral mandibular parasymphysis fracture. A review of the clinical features of superolateral dislocation of the mandibular condyle and the possible techniques of its reduction ranging from the most conservative means to extensive surgical interventions is presented. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Biomechanical analysis of acromioclavicular joint dislocation repair using coracoclavicular suspension devices in two different configurations.

    Science.gov (United States)

    Abat, Ferran; Sarasquete, Juan; Natera, Luis Gerardo; Calvo, Ángel; Pérez-España, Manuel; Zurita, Néstor; Ferrer, Jesús; del Real, Juan Carlos; Paz-Jimenez, Eva; Forriol, Francisco

    2015-09-01

    The best treatment option for some acromioclavicular (AC) joint dislocations is controversial. For this reason, the aim of this study was to evaluate the vertical biomechanical behavior of two techniques for the anatomic repair of coracoclavicular (CC) ligaments after an AC injury. Eighteen human cadaveric shoulders in which repair using a coracoclavicular suspension device was initiated after injury to the acromioclavicular joint were included in the study. Three groups were formed; group I (n = 6): control; group II (n = 6): repair with a double tunnel in the clavicle and in the coracoid (with two CC suspension devices); group III (n = 6): repair in a "V" configuration with two tunnels in the clavicle and one in the coracoid (with one CC suspension device). The biomechanical study was performed with a universal testing machine (Electro Puls 3000, Instron, Boulder, MA, USA), with the clamping jaws set in a vertical position. The force required for acromioclavicular reconstruction system failure was analyzed for each cadaveric piece. Group I reached a maximum force to failure of 635.59 N (mean 444.0 N). The corresponding force was 939.37 N (mean 495.6 N) for group II and 533.11 N (mean 343.9 N) for group III. A comparison of the three groups did not find any significant difference despite the loss of resistance presented by group III. Anatomic repair of coracoclavicular ligaments with a double system (double tunnel in the clavicle and in the coracoid) permits vertical translation that is more like that of the acromioclavicular joint. Acromioclavicular repair in a "V" configuration does not seem to be biomechanically sufficient.

  12. Non-operative treatment of a fracture to the coracoid process with acromioclavicular dislocation in an adolescent

    Directory of Open Access Journals (Sweden)

    Vera Pedersen

    2014-08-01

    Full Text Available Coracoid process fractures are rare and often associated with dislocations of the acromioclavicular (AC joint. There is little evidence about the treatment of these injuries in adolescents, but the few case reports published recommend surgery. We report a case of a dislocated epiphyseal fracture to the base of the coracoid process with AC joint dislocation in a 14-year-old ice-hockey player following direct impact to his left shoulder. Since magnetic resonance tomography revealed intact AC and coracoclavicular ligaments, we initiated non-operative treatment with immobilization and unloading of the shoulder by an abduction brace allowing limited rotation for 6 weeks. This treatment resulted in complete recovery after 8 weeks and return to full sports on first league level after 3 month. In conclusion, non-operative treatment of coracoid base fractures with concomitant AC-joint injury in the adolescent can result in excellent functional results and early recovery.

  13. Irreducible lateral dislocation of the elbow.

    Directory of Open Access Journals (Sweden)

    Chhaparwal M

    1997-01-01

    Full Text Available A rare case of an irreducible post-traumatic lateral dislocation of elbow is presented. The mechanism of injury was fall on a flexed elbow with trauma on its medial aspect resulting in pronation of the forearm. At open reduction, the brachialis muscle was in the form of a tight band which prevented reduction. The ulnar nerve was entrapped in the joint.

  14. Management of primary anterior shoulder dislocations using immobilization.

    Science.gov (United States)

    Smith, Brent I; Bliven, Kellie C Huxel; Morway, Genoveffa R; Hurbanek, Jason G

    2015-05-01

    Reference/Citation : Paterson WH, Throckmorton TW, Koester M, Azar FM, Kuhn JE. Position and duration of immobilization after primary anterior shoulder dislocation: a systemic review and meta-analysis of the literature. J Bone Joint Surg Am. 2010;92(18):2924-2933. Does an optimum duration and position of immobilization after primary anterior shoulder dislocation exist for reducing recurrence rates? MEDLINE/PubMed, EMBASE, and Cochrane databases were searched up to December 2009 without limitations. The search terms for all databases used were shoulder AND dislocation and shoulder AND immobilization. Criteria used to include articles were (1) English language, (2) prospective level I or level II studies (according to Journal of Bone & Joint Surgery guidelines), (3) nonoperative management of initial anterior shoulder dislocation, (4) minimum follow-up of 1 year, and (5) rate of recurrent dislocation as a reported outcome. A standardized evaluation method was used to extract data to allow assessment of methods issues and statistical analysis to determine sources of bias. The primary outcome was the recurrence rate after nonoperative management of anterior shoulder dislocation. Additional data extracted and used in subanalyses included duration and position of immobilization and age at the time of initial dislocation. Data were analyzed to determine associations among groups using 2-tailed Fisher exact tests. For pooled categorical data, relative risk of recurrent dislocation, 95% confidence intervals, and heterogeneity using the I(2) statistic and χ(2) tests were calculated for individual studies. The Mantel-Haenszel method was used to combine studies and estimate overall relative risk of recurrent dislocation and 95% confidence intervals. The statistical difference between duration of immobilization and position was determined using z tests for overall effect. Pooled results were presented as forest plots. In the initial search of the databases, the authors

  15. Bipolar fracture dislocation of clavicle: A report of osteosynthesis and early soft tissue reconstruction

    Directory of Open Access Journals (Sweden)

    Renaldi Prasetia

    Full Text Available Introduction: Bipolar dislocation of the clavicle, also called bifocal or pan-articular dislocation or floating clavicle, is an uncommon traumatic injury. The injury of this case is also concomitant with distal third clavicle and coracoid fracture. This article aimed to report the experience of performing osteosynthesis and early soft tissue reconstruction on these injuries. Case report: We reported a case of bipolar clavicle fracture-dislocation in concomitant with coracoid fracture in a man, aged 32 years old, successfully treated 24 days after accident by fixation of both fractures and early simultaneous reconstruction of sternoclavicular- acromioclavicular-coracoclavicular joints. Discussion: These injuries are rare and capable of causing many complications if they are treated improperly. It is compulsory to carefully assess any fractured clavicle along its whole length, both clinically and radiologically. Various options, from non-operative to operative, have been reported to manage such of these cases. Early bony fixation and soft tissue reconstruction can correct the alignment of clavicle and recover the function of sterno-clavicular and acromio-clavicular- joints promptly. Conclusion: Fracture osteosynthesis and early soft tissue reconstruction can be regarded as an option treatment for bipolar fracture-dislocation of the clavicle to facilitate prompt treatment and early rehabilitation. Keywords: Bipolar dislocation, Floating clavicle, Early reconstruction, Soft tissue reconstruction

  16. Proximal tibiofibular joint: Rendezvous with a forgotten articulation

    Directory of Open Access Journals (Sweden)

    Amitav Sarma

    2015-01-01

    Full Text Available The proximal tibiofibular joint (PTFJ is a plane type synovial joint. The primary function of the PTFJ is dissipation of torsional stresses applied at the ankle and the lateral tibial bending moments besides a very significant tensile, rather than compressive weight bearing. Though rare, early diagnosis and treatment of the PTFJ dislocation are essential to prevent chronic joint instability and extensive surgical intervention to restore normal PTFJ biomechanics, ankle and knee function, especially in athletes prone to such injuries. PTFJ dislocations often remain undiagnosed in polytrauma scenario with ipsilateral tibial fracture due to the absence of specific signs and symptoms of PTFJ injury. Standard orthopedic textbooks generally describe no specific tests or radiological signs for assessment of the integrity of this joint. The aim of this paper was to review the relevant clinical anatomy, biomechanics and traumatic pathology of PTFJ with its effect on the knee emphasizing the importance of early diagnosis through a high index of suspicion. Dislocation of the joint may have serious implications for the knee joint stability since fibular collateral ligament and posterolateral ligament complex is attached to the upper end of the fibula. Any high energy knee injury with peroneal nerve palsy should immediately raise the suspicion of PTFJ dislocation especially if the mechanism of injury involved knee twisting in flexion beyond 80° and in such cases a comparative radiograph of the contralateral side should be performed. Wider clinical awareness can avoid both embarrassingly extensive surgeries due to diagnostic delays or unnecessary overtreatment due to misinformation on the part of the treating surgeon.

  17. Educational Quality of YouTube Videos in Thumb Exercises for Carpometacarpal Osteoarthritis: A Search on Current Practice.

    Science.gov (United States)

    Villafañe, Jorge Hugo; Cantero-Tellez, Raquel; Valdes, Kristin; Usuelli, Federico Giuseppe; Berjano, Pedro

    2017-09-01

    Conservative treatments are commonly performed therapeutic interventions for the management of carpometacarpal (CMC) joint osteoarthritis (OA). Physical and occupational therapies are starting to use video-based online content as both a patient teaching tool and a source for treatment techniques. YouTube is a popular video-sharing website that can be accessed easily. The purpose of this study was to analyze the quality of content and potential sources of bias in videos available on YouTube pertaining to thumb exercises for CMC OA. The YouTube video database was systematically searched using the search term thumb osteoarthritis and exercises from its inception to March 10, 2017. Authors independently selected videos, conducted quality assessment, and extracted results. A total of 832 videos were found using the keywords. Of these, 10 videos clearly demonstrated therapeutic exercise for the management of CMC OA. In addition, the top-ranked video found by performing a search of "views" was a video with more than 121 863 views uploaded in 2015 that lasted 12.33 minutes and scored only 2 points on the Global Score for Educational Value rating scale. Most of the videos viewed that described conservative interventions for CMC OA management have a low level of evidence to support their use. Although patients and novice hand therapists are using YouTube and other online resources, videos that are produced by expert hand therapists are scarce.

  18. Dyspnea in a case of shoulder dislocation – to beware of this rare life-threatening symptom

    Directory of Open Access Journals (Sweden)

    Joshi Satyen Praful

    2016-01-01

    Full Text Available Shoulder dislocation is a common injury in orthopedic practice. In an acute presentation, closed reduction of the shoulder joint leads to an uneventful recovery. However, in the developing world neglected shoulder dislocation and treatments from quacks are not uncommon. Improper treatment and neglect can rarely become life threatening. We present one such case, emphasizing the need to investigate the symptom of dyspnea in a patient with history of shoulder dislocation.

  19. Acute acromioclavicular dislocation: a cheaper, easier and all-arthroscopic system. Is it effective in nowadays economical crisis?

    Science.gov (United States)

    Sastre, Sergi; Dada, Michelle; Santos, Simon; Lozano, Lluis; Alemany, Xavier; Peidro, Lluis

    2015-03-01

    The objective of this manuscript is to show an effective, easier and cheaper way to reduce acute acromioclavicular (AC) dislocation type III and V (Rockwood classification). Numerous procedures have been described for surgical management of acromioclavicular joint disruption. Newest devices involve an arthroscopic technique that allows nonrigid anatomic fixation of the acromioclavicular joint. Arthroscopically assisted treatment of acute AC joint dislocation is advantageous because it provides good clinical results and few complications. It also allows reviewing glenohumeral associated lesions. This surgical technique requires no specific implants to achieve a correct AC reduction. Actually, economical advantages are very important factors to decide the use of determinate surgical techniques.

  20. An unusual case of posterior elbow dislocation with proximal radioulnar translocation.

    Science.gov (United States)

    Gómez Robledo, J; Díez Lizuaín, M L

    2018-03-07

    We present a 9-year-old girl who suffered a posterior dislocation of the right elbow with a proximal translocation between the ulna and the radius. It is a type of exceptional dislocation which in our case was not accompanied by lesions of the joint surfaces of the elbow unlike most cases already published. This article stresses the importance of making an early diagnosis of this variety of dislocation; this is the best way to prevent it from going unnoticed. The use of Computed Tomography (CT) helped this early diagnosis, enabling an immediate closed orthopaedic reduction and achieving a cure without sequelae. Copyright © 2018 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  1. Primary ankle arthrodesis for neglected open Weber B ankle fracture dislocation.

    Science.gov (United States)

    Thomason, Katherine; Ramesh, Ashwanth; McGoldrick, Niall; Cove, Richard; Walsh, James C; Stephens, Michael M

    2014-01-01

    Primary ankle arthrodesis used to treat a neglected open ankle fracture dislocation is a unique decision. A 63-year-old man presented to the emergency department with a 5-day-old open fracture dislocation of his right ankle. After thorough soft tissue debridement, primary arthrodesis of the tibiotalar joint was performed using initial Kirschner wire fixation and an external fixator. Definitive soft tissue coverage was later achieved using a latissimus dorsi free flap. The fusion was consolidated to salvage the limb from amputation. The use of primary arthrodesis to treat a compound ankle fracture dislocation has not been previously described. Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  2. A Rare Case of Neglected Traumatic Anterior Dislocation of Hip in a Child.

    Science.gov (United States)

    Mootha, Aditya Krishna; Mogali, Kasi Viswanadam

    2016-01-01

    Post traumatic hip dislocations are very rare in children. Neglected anterior hip dislocations in children are not described in literature so far. Here, we present a case of 6 weeks old anterior hip dislocation successfully managed by open reduction. A 9-year-old male child presented with neglected anterior hip dislocation on left side. Open reduction carried out through direct anterior approach to hip. Congruent reduction is achieved. At final follow up of 1 year, the child had unrestricted activities of daily living and no radiological signs of osteonecrosis or any joint space reduction. There is paucity of literature over neglected post traumatic anterior hip dislocations in children. The treatment options vary from closed reduction after heavy traction to sub trochanteric osteotomy. However, we feel that open reduction through direct anterior approach is the preferred mode of management whenever considered possible.

  3. Unusual inferior dislocation of shoulder: reduction by two-step maneuver: a case report

    Directory of Open Access Journals (Sweden)

    Patro Dilip K

    2009-11-01

    Full Text Available Abstract Dislocation of the shoulder is the commonest of all large joint dislocations. Inferior dislocation constitutes 0.5% of all shoulder dislocations. It characteristically presents with overhead abduction of the arm, the humerus being parallel to the spine of scapula. We present an unusual case of recurrent luxatio erecta in which the arm transformed later into an adducted position resembling the more common anterior shoulder dislocation. Such a case has not been described before in English literature. Closed reduction by the two-step maneuver was successful with a single attempt. MRI revealed posterior labral tear and a Hill-Sachs variant lesion on the superolateral aspect of humeral head. Immobilisation in a chest-arm bandage followed by physiotherapy yielded excellent results. The case is first of its kind; the unusual mechanism, unique radiological findings and alternate method of treatment are discussed.

  4. Intra-Articular Entrapment of the Medial Epicondyle following a Traumatic Fracture Dislocation of the Elbow in an Adult

    Science.gov (United States)

    Hassan, Youssef G.; Joukhadar, Nabih I.

    2018-01-01

    Medial epicondyle entrapment after an acute fracture dislocation of the elbow is a common finding in the pediatric population, but a rare finding in adults. We present a case of an adult patient diagnosed with a traumatic fracture dislocation of the elbow joint with intra-articular entrapment of the medial epicondyle. After initial evaluation, closed reduction was done. Stability testing after reduction showed an unstable joint; thus, open reduction and internal fixation was decided. PMID:29666736

  5. Rehabilitation of neglected Monteggia fracture: Dislocations in children.

    Science.gov (United States)

    Yıldırım, Azad; Nas, Kemal

    2017-11-06

    There are limited studies related to the rehabilitation of neglected Monteggia fracture-dislocations. This study reports the results of the rehabilitation of neglected Monteggia fractures and dislocations and the best treatment options available. Thirteen children were rehabilitated between 2009 and 2012. A retrospective chart review was conducted to record the following: age, gender, anatomic region of fractures, time delay from symptom onset to fracture, Bado classification, Mayo Elbow Performance Index (MEPI) which includes pain, range of motion and daily life comfort, surgeries, length of hospitalization, location and pattern of fracture, length of follow-up and complications. The study group included thirteen children and adolescents; eleven males and two females with a mean age of 8.5 (range 2-15) years. According to the Bado classification, 11 patients had type 1, one had type 3 and one had type 4 fracture-dislocations. For Mayo Elbow Performance Index (MEPI) scales, patients that were less than ten years old had greater mean scores. Two patients had superficial infection, one had subluxation, one had osteoarthritis, one had delayed bone union and two had rigidity at the elbow. The goals of elbow rehabilitation following Neglected Monteggia cases include restoring function by restoring motion and muscle performance; influencing scar remodeling and preventing joint contracture; and restoring or maintaining joint stability. Patients aged younger than 10 years and intervals of less than one-year, between trauma and diagnosis, as well as early and effective rehabilitation were found as important parameters regarding favorable outcomes.

  6. Treatment of neglected elbow dislocations with the help of hinged external fixator: Report of two cases

    Directory of Open Access Journals (Sweden)

    Özgür Karakoyun

    2014-06-01

    Full Text Available Elbow dislocations are cases that have to be treated in emergency conditions. Neglected elbow dislocations are seen very rarely and the treatment of such cases are more complicated than acute cases. We present two cases of neglected elbow dislocations treated with open reduction and hinged external fixators. Case 1: 23 year old female patient had a neglected posterior dislocation of left elbow with ipsilateral humeral shaft fracture caused by car accident. The patient was treated after 3 months of initial trauma. We have performed open reduction for the joint. After that we fixed the joint whit a hinged external fixator. The humeral shaft fracture was also fixed with the components of the external fixator. Case 2: 33 year male patient had a large bone and soft tissue defect around the left elbow accompanying with neglected medial elbow dislocation. He presented to our clinic with a delay of 2 months. The patient was treated with open reduction and hinged external fixator after reconstruction of bone defect of distal humerus. Conclusion: The treatment of neglected cases is quite challenging. Open reduction and external fixation has satisfactory results in treatment of late cases of elbow dislocation with the possibility of early rehabilitation. This method can be considered as an option for such cases. J Clin Exp Invest 2014; 5 (2: 443-446

  7. Congenital Deficiency of Distal Ulna and Dislocation of the Radial Head Treated by Single Bone Forearm Procedure

    Directory of Open Access Journals (Sweden)

    Paragjyoti Gogoi

    2014-01-01

    Full Text Available Congenital deficiency of part of distal ulna affecting the distal radio-ulnar joint is a rare disorder. It is even rarer to find the association of proximal radio-ulnar joint dislocation along with distal ulnar deficiency. This type of congenital forearm anomaly is difficult to treat. Conversion to a single bone forearm in the expense of pronation-supination movement is a viable option. By doing so the elbow and wrist can be stabilized; however movement is possible in only one plane. We are describing here a girl of 8 years having proximal radio-ulnar joint dislocation along with deficiency of distal ulna treated by converting into a single bone forearm.

  8. Dislocation following total knee arthroplasty: A report of six cases

    Directory of Open Access Journals (Sweden)

    Villanueva Manuel

    2010-01-01

    Full Text Available Background: Dislocation following total knee arthroplasty (TKA is the worst form of instability. The incidence is from 0.15 to 0.5%. We report six cases of TKA dislocation and analyze the patterns of dislocation and the factors related to each of them. Materials and Methods: Six patients with dislocation of knee following TKA are reported. The causes for the dislocations were an imbalance of the flexion gap (n=4, an inadequate selection of implants (n=1, malrotation of components (n=1 leading to incompetence of the extensor mechanism, or rupture of the medial collateral ligament (MCC. The patients presented complained of pain, giving way episodes, joint effusion and difficulty in climbing stairs. Five patients suffered posterior dislocation while one anterior dislocation. An urgent closed reduction of dislocation was performed under general anaesthesia in all patients. All patients were operated for residual instability by revision arthroplasty after a period of conservative treatment. Results: One patient had deep infection and knee was arthrodesed. Two patients have a minimal residual lag for active extension, including a patient with a previous patellectomy. Result was considered excellent or good in four cases and fair in one, without residual instability. Five out of six patients in our series had a cruciate retaining (CR TKA designs: four were revised to a posterior stabilized (PS TKA and one to a rotating hinge design because of the presence of a ruptured MCL. Conclusion: Further episodes of dislocation or instability will be prevented by identifying and treating major causes of instability. The increase in the level of constraint and correction of previous technical mistakes is mandatory.

  9. Special examinations in neuroradiology diagnostic of the neurological complications in atlanto axial dislocations

    International Nuclear Information System (INIS)

    Mihale, J.

    1998-01-01

    We report about contribution myelography, CT myelography, vertebral angiography and angio-cinematography, CT and MRI in diagnostic of the neurological complications of the ventral atlanto axial dislocation in 126 patients with progressive polyarthritis and ankylosing spondylarthritis. On the myelogram, and CT myelogram we visualized narrowing of the spinal channel in ventral atlanto axial dislocation. In patients with unreponibile dislocation up to the stop contrast medium between C1 and C2 vertebrae. With vertebral angiography and angio-cinematography we visualized changes in course of the arteries until with stop of the contrast medium in ante-flexion of the head in patients with unreponibile atlanto axial dislocation. On the MRI studies we visualized pathological changes in the front and back of the atlanto odontoidal joints and compression of the spinal cord. (author)

  10. To the question of the immobilization after the reduction of primary traumatic shoulder dislocation (review

    Directory of Open Access Journals (Sweden)

    V. A. Aslanov

    2014-01-01

    Full Text Available The article presented the evolution of views on the conservative treatment of primary traumatic shoulder dislocation. The shortcomings of common method of conservative treatment for shoulder dislocation are listed, as well as the ways to eliminate them. The trends for further investigations for this problem are marked.The authors conclude that the standard treatment for primary traumatic shoulder dislocation is the immobilization of the damaged shoulder joint immediately after atraumatic traction reposition in the position of external rotation for a period of 3 to 7 weeks.

  11. Osteoarthritis of the first carpometacarpal joint: a study of radiology and clinical epidemiology:

    DEFF Research Database (Denmark)

    Sonne-Holm, Stig; Jacobsen, J

    2006-01-01

    Epidemiological studies show an increased prevalence of osteoarthritis of the knee and hand with increased body mass index [BMI]. Osteoarthritis of the hip joint is not related to BMI. The connection between obesity and osteoarthritis cannot exclusively be explained by genetic factors or by the a...

  12. Is early osteoarthritis associated with differences in joint congruence?

    Science.gov (United States)

    Conconi, Michele; Halilaj, Eni; Parenti Castelli, Vincenzo; Crisco, Joseph J

    2014-12-18

    Previous studies suggest that osteoarthritis (OA) is related to abnormal or excessive articular contact stress. The peak pressure resulting from an applied load is determined by many factors, among which is shape and relative position and orientation of the articulating surfaces or, referring to a more common nomenclature, joint congruence. It has been hypothesized that anatomical differences may be among the causes of OA. Individuals with less congruent joints would likely develop higher peak pressure and thus would be more exposed to the risk of OA onset. The aim of this work was to determine if the congruence of the first carpometacarpal (CMC) joint differs with the early onset of OA or with sex, as the female population has a higher incidence of OA. 59 without and 38 with early OA were CT-scanned with their dominant or arthritic hand in a neutral configuration. The proposed measure of joint congruence is both shape and size dependent. The correlation of joint congruence with pathology and sex was analyzed both before and after normalization for joint size. We found a significant correlation between joint congruence and sex due to the sex-related differences in size. The observed correlation disappeared after normalization. Although joint congruence increased with size, it did not correlate significantly with the onset of early OA. Differences in joint congruence in this population may not be a primary cause of OA onset or predisposition, at least for the CMC joint. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Congenital dislocation of the knee in Ibadan, Nigeria | Omololu ...

    African Journals Online (AJOL)

    Between January 1996 and December 2001, 41 congenital dislocations of the knee joints (30 patients) were reduced with closed methods by immediate reduction without anaesthesia and serial casting in plaster of Paris immobilization for a period of six to eight weeks. The patients' age ranged from the age of one week to ...

  14. Three-dimensional versus two-dimensional sonography of the temporomandibular joint in comparison to MRI

    Energy Technology Data Exchange (ETDEWEB)

    Landes, Constantin A. [Oral, Maxillofacial and Plastic Facial Surgery, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: c.landes@lycos.com; Goral, Wojciech A. [Oral, Maxillofacial and Plastic Facial Surgery, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: w.goral@gmx.de; Sader, Robert [Oral, Maxillofacial and Plastic Facial Surgery, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: r.sader@em.uni-frankfurt.de; Mack, Martin G. [Department of Diagnostic and Interventional Radiology, Frankfurt University Medical Centre, Theodor-Stern-Kai 7, 60596 Frankfurt (Germany)]. E-mail: martinmack@arcor.de

    2007-02-15

    Aim: To compare clinical feasibility of static two-dimensional (2D) to three-dimensional (3D) sonography of the temporomandibular joint (TMJ) in assessment of disk dislocation and joint degeneration compared to magnetic resonance imaging (MRI). Method: Thirty-three patients, 66 TMJ were prospectively sonographed 2D and 3D (8-12.5 MHz step motor scan), in occlusion and maximum opening with a probe position parallel inferior to the zygomatic arch. Axial 2D images were judged independent from the 3D scans; 3D volumes were cut axial, sagittal, frontal and rotated in real-time. Disk position and joint degeneration were assessed and compared to a subsequent MRI examination. Results: The specific appearance of the disk was hypoechogenic overlying a hyperechogenic condyle in axial (2D) or sagittal and frontal (3D) viewing. Specificity of 2D sonography for disk dislocation was 63%, sensitivity 58%, accuracy 64%, positive predictive value 46%, negative predictive value 73%; for joint degeneration synonymously 59/68/61/38/83%. 3D sonography for disk displacement reached synonymously 68/60/69/51/76%, for joint degeneration 75/65/73/48/86%. 2D sonographic diagnoses of disk dislocation in the closed mouth position and of joint degeneration showed significantly different results from the expected values (MRI) in {chi} {sup 2} testing; 3D diagnoses of disk dislocation in closed mouth position, of joint degeneration, 2D and 3D diagnoses in open mouth position were nonsignificant. Conclusions: Acceptable was the overall negative predictive value, as specificity and accuracy for joint degeneration in 3D. 3D appears superior diagnosing disk dislocation in closed mouth position as for overall joint degeneration. Sensitivity, accuracy and positive predictive value will have to ameliorate with future equipment of higher resolution in real-time 2D and 3D, if sonographic screening shall be clinically applied prior to MRI.

  15. Bipolar fracture dislocation of clavicle: A report of osteosynthesis and early soft tissue reconstruction.

    Science.gov (United States)

    Prasetia, Renaldi; Rasyid, Hermawan Nagar

    2017-01-01

    Bipolar dislocation of the clavicle, also called bifocal or pan-articular dislocation or floating clavicle, is an uncommon traumatic injury. The injury of this case is also concomitant with distal third clavicle and coracoid fracture. This article aimed to report the experience of performing osteosynthesis and early soft tissue reconstruction on these injuries. We reported a case of bipolar clavicle fracture-dislocation in concomitant with coracoid fracture in a man, aged 32 years old, successfully treated 24days after accident by fixation of both fractures and early simultaneous reconstruction of sternoclavicular- acromioclavicular-coracoclavicular joints. These injuries are rare and capable of causing many complications if they are treated improperly. It is compulsory to carefully assess any fractured clavicle along its whole length, both clinically and radiologically. Various options, from non-operative to operative, have been reported to manage such of these cases. Early bony fixation and soft tissue reconstruction can correct the alignment of clavicle and recover the function of sterno-clavicular and acromio-clavicular- joints promptly. Fracture osteosynthesis and early soft tissue reconstruction can be regarded as an option treatment for bipolar fracture-dislocation of the clavicle to facilitate prompt treatment and early rehabilitation. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  16. Dislocation climb models from atomistic scheme to dislocation dynamics

    OpenAIRE

    Niu, Xiaohua; Luo, Tao; Lu, Jianfeng; Xiang, Yang

    2016-01-01

    We develop a mesoscopic dislocation dynamics model for vacancy-assisted dislocation climb by upscalings from a stochastic model on the atomistic scale. Our models incorporate microscopic mechanisms of (i) bulk diffusion of vacancies, (ii) vacancy exchange dynamics between bulk and dislocation core, (iii) vacancy pipe diffusion along the dislocation core, and (iv) vacancy attachment-detachment kinetics at jogs leading to the motion of jogs. Our mesoscopic model consists of the vacancy bulk dif...

  17. Diffusion along and around dislocations; Diffusion le long et autour des dislocations

    Energy Technology Data Exchange (ETDEWEB)

    Brebec, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-07-01

    We have gathered together in this text some solutions for Fick's equations applicable to diffusion in dislocations. The problems is fairly similar to that of grain boundaries but in this case a further difficulty arises, purely mathematical in fact, due to the supposedly cylindrical shape of the perturbed region around a dislocation. It follows that Fick's equation is used in the form: {partial_derivative}C/{partial_derivative}t=D[{partial_derivative}{sup 2}C/{partial_derivative}r{sup 2}+1/r{partial_derivative}C/{partial_derivative} r + {partial_derivative}{sup 2}C/{partial_derivative}z{sup 2}] in order to express simply the limiting conditions and so that the solution takes into account the symmetry of revolution of the system. This very much complicates the final form of the results. We give here as an illustration a solution obtained using the same hypotheses and making the same approximations as those employed by WHIPPLE for his grain boundary work. Unfortunately the final form is not suitable for a numerical calculation. By making grosser approximations, such a those used by FISHER, it is possible to determine the parameter D/(a{sup 2}D'); the same result as for grain boundary is found i.e that the logarithm of the mean concentration varies linearly with penetration, the slope of this straight line is proportional to {radical}(D/(a{sup 2}D')) Finally we give the exact solution for a platelet of finite thickness assuming that the diffusion in the defect less crystal is negligible and that the surface diffusion is infinitely fast. This is the problem dealt with by HENDRIGKSON and MACHLIN. We arrive at conclusions different to those obtained by these two authors. (author) [French] Nous avons groupe dans ce texte quelques solutions des equations de Fick applicables a la diffusion dans les dislocations. Le probleme est assez analogue a celui des joints de grains mais il s'introduit ici une difficulte supplementaire, d'ailleurs purement mathematique, due au fait de

  18. Distraction, Compression, Extension, and Reduction Combined With Joint Remodeling and Extra-articular Distraction: Description of 2 New Modifications for Its Application in Basilar Invagination and Atlantoaxial Dislocation: Prospective Study in 79 Cases.

    Science.gov (United States)

    Chandra, P Sarat; Prabhu, Manik; Goyal, Nishant; Garg, Ajay; Chauhan, Avnish; Sharma, Bhawani Shankar

    2015-07-01

    Recent strategies for treatment of basilar invagination (BI) and atlantoaxial dislocation (AAD) are based on simultaneous posterior reduction and fixation. To describe new modifications of the procedure distraction, compression, extension, and reduction (DCER), ie, joint remodeling (JRM) and extra-articular distraction (EAD) in patients with "vertical" joints, and to quantify the improvement in joint indices, ie, sagittal inclination (SI), craniocervical tilt (CCT), and coronal inclination. Prospective study (May 2010 to September 2014). Joint indices measured included (normal values): SI (87.15 ± 5.65°), CCT (60.2 ± 9.2°), and coronal inclination (110.3 ± 4.23°). Surgical procedures included DCER alone (performed in SI joints (SI >160°, group III). Seventy-nine patients were selected (mean, 22.5 years of age). All conventional indices improved significantly (P 100°). Joint indices provide useful information for surgical strategy and planning.

  19. Posterior dislocation of a native hip joint associated with ipsilateral per-trochanteric fracture: A rare case report

    Directory of Open Access Journals (Sweden)

    Mazin Fageir

    2018-02-01

    Full Text Available We describe a case of traumatic posterior dislocation of a native hip joint associated with ipsilateral comminuted inter-trochanteric femoral fracture. In our case, closed reduction was attempted but proved unsuccessful. Taking into account the planned subsequent intra-medullary femoral nail, open reduction through a lateral incision was undertaken. Post-operatively, the planned mobility was for a non-weight bearing period of 6 weeks followed by a partial-weight bearing period of 6 weeks before progressing to full-weight bearing. Post-operatively, the patient completed a comprehensive course of physiotherapy. At five months, he was able to walk for five miles over the course of a weekend. At six months, the patient was looking at phased return to work as a fire fighter. Radiographs taken at the time demonstrated evidence of healing to his inter-trochanteric fracture. At ten months, the patient was back to normal duties at work as a fire fighter.

  20. Interaction of 〈1 0 0〉 dislocation loops with dislocations studied by dislocation dynamics in α-iron

    Energy Technology Data Exchange (ETDEWEB)

    Shi, X.J.; Dupuy, L. [CEA, DEN, SRMA, F-91191 Gif-sur-Yvette (France); Devincre, B. [Laboratoire d’Etude des Microstructures, CNRS-ONERA, 29 av. de la Division Leclerc, 92322 Châtillon Cedex (France); Terentyev, D. [SCK–CEN, Nuclear Materials Science Institute, Boeretang 200, B-2400 Mol (Belgium); Vincent, L. [CEA, DEN, SRMA, F-91191 Gif-sur-Yvette (France)

    2015-05-15

    Highlights: • Interactions between edge dislocations and radiation-induced loops were studied by dislocation dynamics. • Dislocation dynamics results are directly compared to molecular dynamics results. • The complex elementary reactions are successfully reproduced. • The critical shear stress to overcome individual loops if reproduced quantitatively. - Abstract: Interstitial dislocation loops with Burgers vector of 〈1 0 0〉 type are formed in α-iron under neutron or heavy ion irradiation. As the density and size of these loops increase with radiation dose and temperature, these defects are thought to play a key role in hardening and subsequent embrittlement of iron-based steels. The aim of the present work is to study the pinning strength of the loops on mobile dislocations. Prior to run massive Dislocation Dynamics (DD) simulations involving experimentally representative array of radiation defects and dislocations, the DD code and its parameterization are validated by comparing the individual loop–dislocation reactions with those obtained from direct atomistic Molecular Dynamics (MD) simulations. Several loop–dislocation reaction mechanisms are successfully reproduced as well as the values of the unpinning stress to detach mobile dislocations from the defects.

  1. Treatment of chronic anterior shoulder dislocation by open reduction and simultaneous Bankart lesion repair

    Directory of Open Access Journals (Sweden)

    Rouhani Alireza

    2010-06-01

    Full Text Available Abstract Background Untreated chronic shoulder dislocation eventually leads to functional disability and pain. Open reduction with different fixation methods have been introduced for most chronic shoulder dislocation. We hypothesized that open reduction and simultaneous Bankart lesion repair in chronic anterior shoulder dislocation obviates the need for joint fixation and leads to better results than previously reported methods. Methods Eight patients with chronic anterior dislocation of shoulder underwent open reduction and capsulolabral complex repair after an average delay of 10 weeks from injury. Early motion was allowed the day after surgery in the safe position and the clinical and radiographic results were analyzed at an average follow-up of one year. Results The average Rowe and Zarin's score was 86 points. Four out of eight shoulders were graded as excellent, three as good and one as fair (Rowe and Zarins system. All patients were able to perform their daily activities and they had either mild or no pain. Anterior active forward flexion loss averaged 18 degrees, external active rotation loss averaged 17.5 degrees and internal active rotation loss averaged 3 vertebral body levels. Mild degenerative joint changes were noted in one patient. Conclusion The results show that the overall prognosis for this method of operation is more favorable than the previously reported methods and we recommend concomitant open reduction and capsulolabral complex repair for the treatment of old anterior shoulder dislocation. Level of Evidence Therapeutic study, Level IV (case series [no, or historical, control group

  2. Timing of Surgical Reduction and Stabilization of Talus Fracture-Dislocations.

    Science.gov (United States)

    Buckwalter V, Joseph A; Westermann, Robert; Mooers, Brian; Karam, Matthew; Wolf, Brian

    Talus fractures with associated dislocations are rare but have high rates of complications, including avascular necrosis (AVN). Management of these injuries involves urgent surgical reduction and fixation, although there are no definitive data defining an operative time frame for preserving the blood supply and preventing complications. To determine the effect of time to surgical reduction of talus fractures and talus fracture-dislocations on rates of AVN and posttraumatic osteoarthritis (PTOA), we retrospectively reviewed talus fractures surgically managed at a level I trauma center during the 10-year period 2003 to 2013. Operative reports were obtained and reviewed, and 3 independent reviewers, using the Hawkins and AO/OTA (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association) systems, classified the injuries on plain radiographs. Analysis of AO/OTA 81 fractures with associated tibiotalar, subtalar, or talonavicular dislocations was performed. Primary outcomes were presence of AVN/PTOA and subsequent arthrodesis of tibiotalar or subtalar joints. We identified 106 surgically managed talus fractures. Rates of AVN/PTOA were 41% for all talus fractures and 50% for talus fracture-dislocations. Mean time to surgical reduction was not significant for development of AVN/PTOA for all talus fractures (P = .45) or talus fracture-dislocations (P = .29). There was no difference in age (P = .20), body mass index (P = .45), or polytrauma (P = .79) between patients who developed AVN and those who did not. Open fractures were significantly correlated with the development of AVN/PTOA (P = .009). Talar fracture-dislocations are devastating injuries with high rates of complications. Our data suggest there is no effect of time from injury to surgical reduction of talus fractures or talus fracture-dislocations on rates of AVN and PTOA.

  3. A modified technique of reconstruction for complete acromioclavicular dislocation: a prospective study.

    Science.gov (United States)

    Tienen, Tony G; Oyen, Jan F C H; Eggen, Peter J G M

    2003-01-01

    Many procedures, both nonoperative and operative, have been described for treatment of complete acromioclavicular dislocations. The best primary treatment, however, still remains unclear. We present a new surgical technique in which the clavicle is reduced to an anatomic position, the coracoacromial ligament is transferred to the clavicle, and acromioclavicular joint fixation is accomplished with the use of absorbable, braided suture cord. Twenty-one patients underwent the modified technique of reconstruction. Patients were included only if they had sustained a Rockwood type V acromioclavicular dislocation and were extremely active in competitive sports before dislocation occurred. Eighteen patients returned to their sports without pain within 2.5 months after operation. The mean follow-up was 35.7 months. The average Constant score at last follow-up was 97. Radiographs taken at this time confirmed anatomic reduction in 18 patients, residual subluxation in 2 patients, and, in 1 patient, redislocation of the joint that occurred because of infection. Six patients had radiographic evidence of coracoclavicular ossifications. All patients developed a wide scar. Considering its operative simplicity, the advantage of absorbable augmentation of the clavicular reduction, and the low rate of recurrence, this technique may be an attractive alternative in this particular group of patients.

  4. A RARE CASE OF IPSILATERAL HIP AND KNEE DISLOCATION

    Directory of Open Access Journals (Sweden)

    Deepak

    2015-06-01

    Full Text Available High velocity road traffic accidents leads to complicated lower limb injuries. Such injuries demand highly experienced surgeon and are associated with high morbidity and mortality. Hip or knee dislocations are two different orthopaedic emergencies. Concomitant fracture dislocation of the hip and knee is rare and very few cases have been reported in the literature. A 45 year old man with history of fall from motorcycle came to the casualty. He had ipsilateral hip and knee dislocation. Immediately patient was shifted to operation theatre and closed reduction was performed under general anaesthesia. Reduction was confirmed under fluoroscopy and post-operative x-rays were taken. The functional results were excellent. After 2 months patient made an uncomplicated recovery and had satisfactory functional outcome with right hip having 110⁰ flexion and right knee flexes to 120⁰.There was no neurological deficit. The urgency, that the treating surgeon shows in managing these injuries, significantly affects the prognosis and outcome finally achieved by these patients (golden period in reducing the hip joint has been described to be 6 hours.

  5. Late dislocation of rotating platform in New Jersey Low-Contact Stress knee prosthesis.

    Science.gov (United States)

    Huang, Chun-Hsiung; Ma, Hon-Ming; Liau, Jiann-Jong; Ho, Fang-Yuan; Cheng, Cheng-Kung

    2002-12-01

    Five patients with late rotational dislocation of the rotating platform bearing in the New Jersey Low-Contact Stress total knee arthroplasty are reported. The prostheses had functioned well for 8 to 12 years before failure. Preoperative radiographs showed asymmetric femorotibial joint spaces. Entrapment of the dislocated bearing in three patients and spontaneous reduction of the dislocated bearing in another two patients were seen at revision. Femorotibial ligamentous instability was found after reduction. The retrieved polyethylene bearings showed advanced wear and cold flow deformities and the thickness was reduced. The revision arthroplasty was accomplished by replacement with a thicker bearing element. Progressive femorotibial ligament laxity and reduction of the thickness of polyethylene with wearing break down the originally well-balanced soft tissue tension of the knee. The rotational degree of the rotating platform bearing is unrestricted, which may result in late dislocation. Polyethylene wear is unavoidable in knee prostheses using metal contact with polyethylene even with a mobile-bearing design. Efforts to reduce polyethylene wear are mandatory.

  6. Traumatic Floating 1st Metacarpal in a 14-Year-Old Boy Managed by Close Reduction and Thumb Spica Immobilization: A Rare Case Report.

    Science.gov (United States)

    Tyagi, Himanshu Ravindra; Kamat, Nandan; Wajekar, Sagar; Mandalia, Saumil H

    2014-01-01

    Double dislocation of thumb metacarpal (MC) is a rare injury which may be secondarily complicated by growth plate injury in children. The management of floating 1st MC is also controversial since the treatment ranges from simple reduction to complex reconstruction surgeries. It is also important to understand the long-term results of different management strategies (close reduction, K-wire fixation, ligament reconstruction) as any residual stiffness or instability of thumb may result in severe disability of the hand. A 14-year-old boy with an alleged history of injury to the thumb due to a fall. The postulated mechanism of injury was forced hyperextension of thumb and axial loading of hand in the prone position. On examination, there was prominent bony swelling over the dorsal aspect of carpometacarpal (CMC) and metacarpophalangeal (MCP) joints which was very tender with diffuse swelling over entire thumb. X-ray showed dorsal dislocation of both MCP and CMC joints, without any fracture (bony avulsion) or volar plate avulsion. Treatment was by way of closed reduction performed by axial traction followed by forced flexion at MCP joint with continuous pressure over the dorsal aspect of the joint. The reduction of CMC joint was done by direct pressure over the dorsal aspect and full abduction of thumb. Following reduction, the thumb was immobilized in a thumb spica. Thus, we conclude it is possible to manage a case of floating 1st MC by closed reduction and immobilization, using proper reduction technique. However, a careful clinical and radiological assessment should be done beforehand for signs of bony injury or ligamentous instability.

  7. Interobserver and intraobserver agreement of ligamentous injuries on conventional MRI after simple elbow dislocation

    Directory of Open Access Journals (Sweden)

    Marc Schnetzke

    2017-02-01

    Full Text Available Abstract Background The primary objective of this study was to assess the interobserver and intraobserver agreement on ligamentous injuries on conventional magnetic resonance imaging (MRI in acute simple elbow dislocation. The secondary objectives were to determine the interobserver agreement on the assessment of joint congruity, joint effusion, loose bodies and chondral lesions on conventional MRI. Methods Conventional MRIs (1.5 Tesla, elbow specific surface coil of 30 patients (40.7 years; range 14–72 with simple elbow dislocations were evaluated by four blinded examiners. An analysis of the interobserver agreement of all raters and for several subgroups (radiologists, orthopaedics, experienced, non-experienced was performed. The examiners assessed the integrity (intact, partial tear, complete tear of the lateral collateral ligament (LCL, medial collateral ligament (MCL, extensor and flexor tendons, as well as the presence of joint congruity, joint effusion, loose bodies and chondral lesions. Agreement strength, correlation and proportion of exact agreement were determined for interobserver agreement, and intraobserver agreement analyses. Results Interobserver agreement of all examiners was fair to moderate for collateral ligaments (LCL: 0.441, MCL: 0.275. Exact agreement of all raters was found in 33.3% for the LCL and in 26.7% for the MCL. The both experienced examiners showed highest agreement strength for the LCL (0.619 and the radiologists showed highest agreement strength for the MCL (0.627, the proportion of exact agreement was 60.0% in both categories. A high proportion of exact agreement regarding joint congruity (90%, joint effusion (100%, loose bodies (96.7% and chondral lesion (80% was found among the radiologists. The evaluation of the intraobserver agreement revealed slight to substantial agreement (0.227 to 0.718 for the collateral ligaments. Conclusions This study shows difficulties in the evaluation of ligaments by

  8. [Elbow dislocation].

    Science.gov (United States)

    de Pablo Márquez, B; Castillón Bernal, P; Bernaus Johnson, M C; Ibañez Aparicio, N M

    Elbow dislocation is the most frequent dislocation in the upper limb after shoulder dislocation. Closed reduction is feasible in outpatient care when there is no associated fracture. A review is presented of the different reduction procedures. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Injury patterns of the acromioclavicular ligament complex in acute acromioclavicular joint dislocations: a cross-sectional, fundamental study.

    Science.gov (United States)

    Maier, Dirk; Jaeger, Martin; Reising, Kilian; Feucht, Matthias J; Südkamp, Norbert P; Izadpanah, Kaywan

    2016-09-06

    Horizontal instability impairs clinical outcome following acute acromioclavicular joint (ACJ) reconstruction and may be caused by insufficient healing of the superior acromioclavicular ligament complex (ACLC). However, characteristics of acute ACLC injuries are poorly understood so far. Purposes of this study were to identify different ACLC tear types, assess type-specific prevalence and determine influencing cofactors. This prospective, cross-sectional study comprised 65 patients with acute-traumatic Rockwood-5 (n = 57) and Rockwood-4 (n = 8) injuries treated operatively by means of mini-open ACJ reduction and hook plate stabilization. Mean age at surgery was 38.2 years (range, 19-57 years). Standardized pre- and intraoperative evaluation included assessment of ACLC tear patterns and cofactors related to the articular disc, the deltoid-trapezoidal (DT) fascia and bony ACJ morphology. Articular disc size was quantified as 0 = absent, 1 = remnant, 2 = meniscoid and 3 = complete. All patients showed complete ruptures of the superior ACLC, which could be assigned to four different tear patterns. Clavicular-sided (AC-1) tears were observed in 46/65 (70.8 %), oblique (AC-2) tears in 12/65 (18.5 %), midportion (AC-3) tears in 3/65 (4.6 %) and acromial-sided (AC-4) tears in 4/65 (6.1 %) of cases. Articular disc size manifestation was significantly (P < .001) more pronounced in patients with AC-1 tears (1.89 ± 0.57) compared to patients with AC-2 tears (0.67 ± 0.89). Other cofactors did not influence ACLC tear patterns. ACLC dislocation with incarceration caused mechanical impediment to anatomical ACJ reduction in 14/65 (21.5 %) of cases including all Rockwood-4 dislocations. Avulsion "in continuity" was a consistent mode of failure of the DT fascia. Type-specific operative strategies enabled anatomical ACLC repair of all observed tear types. Acute ACLC injuries follow distinct tear patterns. There exist clavicular-sided (AC-1

  10. A combined technique for acromioclavicular reconstruction after acute dislocation - technical description and functional outcomes

    Directory of Open Access Journals (Sweden)

    Diogo Lino Moura

    Full Text Available ABSTRACT Objective: This study aims to describe the surgical approach to such injuries and to present the clinical and functional outcomes obtained in a cohort of patients. Methods: This is an observational retrospective study that included 153 patients with acute acromioclavicular joint dislocation, operated between 1999 and 2015. Clinical evaluation included the following outcomes: Constant functional scale, development of complications, time to return to previous work/sport activities, and satisfaction index. The contra-lateral (uninjured shoulder was used as control in subjective outcomes. Radiological evaluation was performed in order to monitor signs of loss of reduction, degenerative joint changes, and coracoclavicular calcifications. Results: The mean age was 29.20 ± 9.53 (16-71, with a large male predominance (91.5%. Follow-up lasted 55.41 ± 24.87 (12-108 months. The mean Constant score attained was 96.45 ± 4.00 (84-100 on operated shoulders and 98.28 ± 1.81 (93-100 on contralateral ones. Almost all patients (98.69% were satisfied with the surgical results. Worse outcomes were observed in acromioclavicular joint dislocations of increasing grade (from type III to V, but worse for type IV, both concerning the Constant score and return to work or sport. The overall incidence of complications was considered low, with the most prevalent being Kirschner wire failure and isolated coracoclavicular ligament calcifications. Conclusion: The surgical technique described is an excellent option in the treatment of acute acromioclavicular joint dislocations of Rockwood grades III to V. This is corroborated by the excellent clinical and functional outcomes and the low rate of complications.

  11. A combined technique for acromioclavicular reconstruction after acute dislocation - technical description and functional outcomes.

    Science.gov (United States)

    Moura, Diogo Lino; Reis E Reis, Augusto; Ferreira, João; Capelão, Manuel; Braz Cardoso, José

    2018-01-01

    This study aims to describe the surgical approach to such injuries and to present the clinical and functional outcomes obtained in a cohort of patients. This is an observational retrospective study that included 153 patients with acute acromioclavicular joint dislocation, operated between 1999 and 2015. Clinical evaluation included the following outcomes: Constant functional scale, development of complications, time to return to previous work/sport activities, and satisfaction index. The contra-lateral (uninjured) shoulder was used as control in subjective outcomes. Radiological evaluation was performed in order to monitor signs of loss of reduction, degenerative joint changes, and coracoclavicular calcifications. The mean age was 29.20 ± 9.53 (16-71), with a large male predominance (91.5%). Follow-up lasted 55.41 ± 24.87 (12-108) months. The mean Constant score attained was 96.45 ± 4.00 (84-100) on operated shoulders and 98.28 ± 1.81 (93-100) on contralateral ones. Almost all patients (98.69%) were satisfied with the surgical results. Worse outcomes were observed in acromioclavicular joint dislocations of increasing grade (from type III to V, but worse for type IV), both concerning the Constant score and return to work or sport. The overall incidence of complications was considered low, with the most prevalent being Kirschner wire failure and isolated coracoclavicular ligament calcifications. The surgical technique described is an excellent option in the treatment of acute acromioclavicular joint dislocations of Rockwood grades III to V. This is corroborated by the excellent clinical and functional outcomes and the low rate of complications.

  12. Subtalar dislocation

    International Nuclear Information System (INIS)

    El-Khoury, G.Y.; Yousefzadeh, D.K.; Mulligan, G.M.; Moore, T.E.

    1982-01-01

    Over a period of three years we have seen nine patients with subtalar dislocation, all of whom sustained violent trauma to the region of the ankle and hind foot. All but one patient were males. Clinically a subtalar dislocation resembles a complicated fracture dislocation of the ankle but a definitive diagnosis can only be made radiographically. The mechanism of injury and radiographic features of this injury are discussed. (orig.)

  13. Estimation of dislocations density and distribution of dislocations during ECAP-Conform process

    Science.gov (United States)

    Derakhshan, Jaber Fakhimi; Parsa, Mohammad Habibi; Ayati, Vahid; Jafarian, Hamidreza

    2018-01-01

    Dislocation density of coarse grain aluminum AA1100 alloy (140 µm) that was severely deformed by Equal Channel Angular Pressing-Conform (ECAP-Conform) are studied at various stages of the process by electron backscattering diffraction (EBSD) method. The geometrically necessary dislocations (GNDs) density and statistically stored dislocations (SSDs) densities were estimate. Then the total dislocations densities are calculated and the dislocation distributions are presented as the contour maps. Estimated average dislocations density for annealed of about 2×1012 m-2 increases to 4×1013 m-2 at the middle of the groove (135° from the entrance), and they reach to 6.4×1013 m-2 at the end of groove just before ECAP region. Calculated average dislocations density for one pass severely deformed Al sample reached to 6.2×1014 m-2. At micrometer scale the behavior of metals especially mechanical properties largely depend on the dislocation density and dislocation distribution. So, yield stresses at different conditions were estimated based on the calculated dislocation densities. Then estimated yield stresses were compared with experimental results and good agreements were found. Although grain size of material did not clearly change, yield stress shown intensive increase due to the development of cell structure. A considerable increase in dislocations density in this process is a good justification for forming subgrains and cell structures during process which it can be reason of increasing in yield stress.

  14. Pneumarthro-CT in diagnosis of recurrent shoulder dislocations and instability

    International Nuclear Information System (INIS)

    Mayr, B.; Siuda, S.; Will, A.; Frenzl, G.; Habermeier, P.; Muenchen Univ.; Muenchen Univ.

    1991-01-01

    32 patients in whom recurrent dislocations or instability of the shoulder had been diagnosed, were examined via CT. Air was used as contrast agent. The results of pneumarthro-CT were re-checked 28 times by surgery and 6 times by arthroscopy. In all cases, Hill-Sachs defects and bony Bankart lesions had been correctly diagnosed. There were no faulty findings. Rate of accuracy of CT in detecting ruptures of the joint capsule from the neck of the scapula was 94%, in detecting lesions of the labrum glenoidale 88%, and in imaging an extended joint capsule 84%. (orig.) [de

  15. Acromioclavicular joint: Normal variation and the diagnosis of dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Keats, T.E.; Pope, T.L. Jr.

    1988-04-01

    Acromioclavicular separation is a common traumatic injury. Diagnosis rests on clinical and radiographic findings. However, normal variation in the alignment of the acromioclavicular joint may make the roentgen diagnosis more difficult. We stress the variations of normal alignment at the acromioclavicular joint and offer suggestions for avoiding pitfalls in this clinical situation.

  16. A morphological study of the hip joint of coxarthrosis by computed tomography

    International Nuclear Information System (INIS)

    Hijikata, Hiromi; Tagawa, Hiroshi; Kashiyama, Masahiro; Yokohata, Yumiko; Kohno, Atsushi; Iida, Keiko

    1983-01-01

    The hip joint in coxarthrosis with severe deformities was studied by CT scan. In this disease, the supero-inferior diameter increased according to the degree of incomplete dislocation, while the antero-posterior diameter remained small. The acetabulum was shallow showing a small distance from the femur axis to the outer plate of the floor, but the floor of the acetabulum was thick with a considerable distance from the axis to the inner plate of the floor. The tangenital angle of the acetabulum was around 20 0 , without remarkable changes depending on the degree of incomplete dislocation. The angle of covering the acetabulum at the center of the capitum was normally around 180 0 , and became smaller in incomplete dislocation, showing poor adaptability. The anterior torsion angle in incomplete dislocation tended to be larger depending upon severity of dislocation. In the cavum medullare of proximal diaphysis of the femur, the antero-posterior diameter was larger than the right-left diameter; and this relation was reversed in the use of artificial joint. Atrophy of the gluteal muscle developed with severeness of coxarthrosis. (Ueda, J.)

  17. Morphological analysis of acromion and hook plate for the fixation of acromioclavicular joint dislocation.

    Science.gov (United States)

    Yoon, Jong Pil; Lee, Yeon Soo; Song, Geun Soo; Oh, Joo Han

    2017-03-01

    Acromioclavicular (AC) joint dislocation is a common sports injury. Hook plate fixation is currently widely used to treat this injury, as it can promote the natural healing of the ligament with good clinical outcomes. However, subacromial erosion and impingement are frequently observed post-operatively. It was hypothesized that the morphology and the contact characteristics between the hook portion and the acromion are the main causes of complications after hook plate fixation with the currently available commercial designs. Three-dimensional reconstructed models of the AC joint obtained from the computed tomographic scans of 23 male and 23 female patients (mean age, 61.1 ± 6.3 years) were evaluated, and multiple anatomical parameters were measured. For the subacromial positioning of the hook plate, an actual hook plate (Synthes Inc., West Chester, PA, USA) was scanned, and the contact between the hook plate and the acromion was estimated. The thicknesses of the acromion and distal clavicle were 9.7 ± 1.5 mm (10.7 mm in men; 8.6 mm in women) and 11.3 ± 1.6 mm (11.6 mm in men; 10.0 mm in women), respectively. The width of the acromion was 28.5 ± 3.6 mm. The mean inclination angle between the hook plate and the acromion was 29.3° ± 9.7° (27.9° in men; 30.6° in women). The hook plate made a point contact with the acromion at 9.2 ± 3.3 mm (31.5 %) from the lateral end of the acromion. The results revealed that the hook made a pinpoint contact with the undersurface of the acromion, and this might explain why complications commonly occur after hook plate fixation. The force concentration phenomenon associated with the hook plate of existing designs results from cases of morphological mismatch, such as excessive inclination and improper occupation of the subacromial space.

  18. Ehler Danlos syndrome with cervical dislocation: An unusual case

    OpenAIRE

    Neeraj Awasthy; Karam Chand

    2008-01-01

    Ehler-Danlos syndrome (EDS) is heritable connective tissue disorders with varied manifestations whose primary clinical features include soft, hyperextensible skin, dystrophic scarring, easy bruising, and joint hypermobility. Os odontoideum describes a condition in which the dens is separated from the axis body. The exact frequency is unknown. Known cases are either incidentally detected or are diagnosed when patients become symptomatic. Cervical dislocation has been described with type VI les...

  19. Missed posterior dislocation of the hip in a head-injured patient with ...

    African Journals Online (AJOL)

    Background: Head injury increases the risk of missed diagnosis by making patient-derived history impossible. The risk of missing a posterior dislocation of the hip in a head-injured patient is aggravated when an ipsilateral femoral shaft fracture co-exists. Adequate radiological evaluation of bone and joints is therefore of ...

  20. Dislocation-dynamics method

    International Nuclear Information System (INIS)

    Van Brutzel, L.

    2015-01-01

    Dislocation-Dynamics (DD) technique is identified as the method able to model the evolution of material plastic properties as a function of the microstructural transformation predicted at the atomic scale. Indeed, it is the only simulation method capable of taking into account the collective behaviour of a large number of dislocations inside a realistic microstructure. DD simulations are based on the elastic dislocation theory following rules inherent to the dislocation core structure often call 'local rules'. All the data necessary to establish the local rules for DD have to come directly from experiment or alternatively from simulations carried out at the atomic scale such as molecular dynamics or ab initio calculations. However, no precise information on the interaction between two dislocations or between dislocations and defects induced by irradiation are available for nuclear fuels. Therefore, in this article the DD technique will be presented and some examples are given of what can be achieved with it. (author)

  1. Simultaneous bilateral elbow dislocation with bilateral medial epicondyle fractures in a 13-year-old female gymnast with hyperlaxity

    Science.gov (United States)

    Bauer, Stefan; Dunne, Ben; Whitewood, Colin

    2012-01-01

    Bilateral simultaneous elbow dislocations are extremely rare and have only been described in 12 cases. In the paediatric population unilateral elbow dislocations are rare with 3–6% of all elbow injuries and there are only few studies describing this injury exclusively in children. There is only one case report of a paediatric patient who sustained a simultaneous bilateral elbow dislocation with medial epicondyle fractures. We present a second paediatric case of simultaneous bilateral elbow dislocation with associated displaced bilateral medial epicondyle fractures in a gymnast with joint hyperlaxity (3 of 5 Wynne-Davies criteria) treated with closed reduction and short-term immobilisation (3 weeks). The patient returned to full trampoline gymnastics between 4 and 5 months postinjury and made an uneventful recovery. PMID:23234820

  2. Modified rerouting procedure for failed peroneal tendon dislocation surgery.

    Science.gov (United States)

    Gaulke, R; Hildebrand, F; Panzica, M; Hüfner, T; Krettek, C

    2010-04-01

    Recurrent dislocation of the peroneal tendons following operative treatment is relatively uncommon, but can be difficult to treat. We asked whether subligamental transposition of the peroneus brevis tendon, fibular grooving, and reattachment of the superior peroneal retinaculum for failed peroneal tendon dislocation surgery would achieve a stable fixation of the peroneal tendons and whether there would be restrictions of ROM or instability of the hindfoot. We reviewed six female patients (mean age, 24.5 years) with general laxity of joints preoperatively and at 6 weeks and 3, 6, and 12 months postoperatively. Within 1 year postoperatively no recurrence was found. In two ankles the extension was restricted 5 degrees to 10 degrees . In another pronation and supination was restricted 5 degrees each. Stability of the ankle increased in four patients and stayed unchanged in two. AOFAS score increased from a mean value of 36 +/- 20.6 preoperatively to 90 +/- 7 postoperatively at 1 year. We conclude transposition of the peroneus brevis tendon is a reasonable treatment for failed peroneal tendon dislocation surgery. Level IV, therapeutic study (prospective case series). See Guidelines for Authors for a complete description of levels of evidence.

  3. Perilunate Dislocation

    Directory of Open Access Journals (Sweden)

    John Jiao

    2016-09-01

    Full Text Available History of present illness: A 25-year-old female presented to the emergency department with left wrist pain following a fall off a skateboard. The patient fell on her outstretched left wrist with the wrist dorsiflexed and reported immediate sharp pain to her left wrist that was worse with movement. She denied other trauma. Significant findings: In the left lateral wrist x-ray, the lunate (outlined in blue is dislocated from the rest of the wrist bones (yellow line but still articulates with the radius (red line. The capitate (yellow line does not sit within the distal articulation of the lunate and is displaced dorsally. Additionally, a line drawn through the radius and lunate (green line fails to intersect with the capitate. This is consistent with a perilunate dislocation. This is compared to a lunate dislocation, where the lunate itself is displaced and turned ventrally (spilled teacup and the proximal aspect does not articulate with the radius. Discussion: A perilunate dislocation is a significant closed wrist injury that is easily missed on standard anterior-posterior imaging. These dislocations are relatively rare, involving only 7% of all carpal injuries and are associated with high-energy trauma onto a hyperextended wrist, such as falls from a height, motor vehicle accidents, and sports injuries.1 An untreated perilunate dislocation is associated with high risk of chronic carpal instability and post-traumatic arthritis. If the mechanism of injury is sufficient to suspect perilunate dislocation, multiple radiographic views of the wrist should be ordered. Patients should receive prompt orthopedic consultation for open reduction and ligamentous repair. Even after successful identification and subsequent surgical repair, median nerve neuropathy and post-traumatic arthritis are frequent.2-3

  4. Dislocation-induced stress in polycrystalline materials: mesoscopic simulations in the dislocation density formalism

    Science.gov (United States)

    Berkov, D. V.; Gorn, N. L.

    2018-06-01

    In this paper we present a simple and effective numerical method which allows a fast Fourier transformation-based evaluation of stress generated by dislocations with arbitrary directions and Burgers vectors if the (site-dependent) dislocation density is known. Our method allows the evaluation of the dislocation stress using a rectangular grid with shape-anisotropic discretization cells without employing higher multipole moments of the dislocation interaction coefficients. Using the proposed method, we first simulate the stress created by relatively simple non-homogeneous distributions of vertical edge and so-called ‘mixed’ dislocations in a disk-shaped sample, which is necessary to understand the dislocation behavior in more complicated systems. The main part of our research is devoted to the stress distribution in polycrystalline layers with the dislocation density rapidly varying with the distance to the layer bottom. Considering GaN as a typical example of such systems, we investigate dislocation-induced stress for edge and mixed dislocations, having random orientations of Burgers vectors among crystal grains. We show that the rapid decay of the dislocation density leads to many highly non-trivial features of the stress distributions in such layers and study in detail the dependence of these features on the average grain size. Finally we develop an analytical approach which allows us to predict the evolution of the stress variance with the grain size and compare analytical predictions with numerical results.

  5. 21 CFR 888.3310 - Hip joint metal/polymer constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint metal/polymer constrained cemented or... Hip joint metal/polymer constrained cemented or uncemented prosthesis. (a) Identification. A hip joint... replace a hip joint. The device prevents dislocation in more than one anatomic plane and has components...

  6. [Treatment of dislocation of shoulder with manipulation of proneposition modified hippocrates method].

    Science.gov (United States)

    Zhao, Hong-Sheng; Jing, Guang-Wu; Zhang, Jian-Jun

    2012-03-01

    To explore the method of reduction of anterior dislocation of shoulder joint, evaluate the clinical effects of proneposition modified Hippocrates methods. From February 1998 to April 2011, 1 028 patients, 689 males and 339 females, with anterior dislocation of shoulder joint were treated with manipulation of proneposition modified Hippocrates methods. The average age was 38.3 years (ranged from 11 to 86 years). Thirty-two cases by Hippocrates method failure to reset success, 86 cases combined with geater tuberosity tore of humerus. One thousand and twenty-seven example applications, it took average 50 s, 1 case was cured due to a combination of humerus surgical neck fracture. Eighty-six cases combined with greater tuberosity tore of humerus, 84 cases reached anatomical reattachment or nearly anatomical reattachment, 2 cases of large bone pieces instability were reduced by percutaneous needle. According to Neer score, there are 1 012 excellent cases, 15 good cases. Proneposition modified Hippocrates method is better than Hippocrates. It has the advantage of anesthesia, lower expense, short replacement, less pain, easier to master, and worth applying widely.

  7. Intrathoracic fracture-dislocation of the humerus - case report and literature review

    Directory of Open Access Journals (Sweden)

    Wilson Carlos Sola Junior

    Full Text Available ABSTRACT Shoulder fracture-dislocations are uncommon. Those associated with intrathoracic dislocation are very rare conditions, resulting from high-energy trauma; usually, the affected limb is in an abduction position. In Brazil, there is only one report of a teenager with displacement of the epiphysis into the chest cavity; the present is the first adult patient report of intrathoracic dislocation of the humerus. The authors present the case of a patient female, aged 56 years, who was hit by motorcycle and thrown approximately 5 meters away. She was rescued on site with thoracic, pelvic, and right upper limb trauma. Her chest was drained due to pneumothorax and multiple fractures of ribs; she was diagnosed with fracture-dislocation in four parts, with intrathoracic dislocation of the humeral head. Displaced forearm bones fracture was also diagnosed; the olecranon, scaphoid, and ischiopubic fractures were not displaced. The patient underwent a joint procedure with a cardiothoracic surgery team to remove the humeral head through thoracotomy and chest drainage; subsequently, a partial arthroplasty of the humerus was performed, with graft from the humeral head and fixation of forearm fractures. Conservative treatment was chosen for the other fractures. After three months, all fractures were healed with gradual functional improvement. The patient remained in physiotherapy and orthopedic monitoring, having been discharged from the thoracic surgery; in a severe depressive episode, the patient committed suicide after 11 months of the trauma.

  8. Acromioclavicular dislocation: treatment and rehabilitation. Current perspectives and trends among Brazilian orthopedists☆

    Science.gov (United States)

    Arliani, Gustavo Gonçalves; Utino, Artur Yudi; Nishimura, Eduardo Misao; Terra, Bernardo Barcellos; Belangero, Paulo Santoro; Astur, Diego Costa

    2015-01-01

    Objective To evaluate the approaches and procedures used by Brazilian orthopedic surgeons in treatment and rehabilitation of acromioclavicular dislocation of the shoulder. Methods A questionnaire comprising eight closed questions that addressed topics relating to treatment and rehabilitation of acromioclavicular dislocation was applied to Brazilian orthopedic surgeons over the three days of the 45th Brazilian Congress of Orthopedics and Traumatology, in 2013. Results A total of 122 surgeons completely filled out the questionnaire and formed part of the sample analyzed. Most of them came from the southeastern region of the country. In this sample, 67% of the participants would choose surgical treatment for patients with grade 3 acromioclavicular dislocation. Regarding the preferred technique for surgical treatment of acute acromioclavicular dislocation, a majority of the surgeons used subcoracoid ligature with acromioclavicular fixation and transfer of the coracoacromial ligament (25.4%). Regarding complications found after surgery had been performed, 43.4% and 32.8% of the participants, respectively, stated that residual deformity of the operated joint and pain were the complications most seen during the postoperative period. Conclusions Although there was no consensus regarding the treatment and rehabilitation of acromioclavicular dislocation, evolution had occurred in some of the topics analyzed in this questionnaire applied to Brazilian orthopedists. However, further controlled prospective studies are needed in order to evaluate the clinical and scientific benefit of these trends. PMID:26535196

  9. Surgical versus conservative management of Type III acromioclavicular dislocation: a systematic review.

    Science.gov (United States)

    Longo, Umile Giuseppe; Ciuffreda, Mauro; Rizzello, Giacomo; Mannering, Nicholas; Maffulli, Nicola; Denaro, Vincenzo

    2017-06-01

    The management of Type III acromioclavicular (AC) dislocations is still controversial. We wished to compare the rate of recurrence and outcome scores of operative versus non-operative treatment of patients with Type III AC dislocations. A systematic review of the literature was performed by applying the PRISMA guidelines according to the PRISMA checklist and algorithm. A search in Medline, PubMed, Cochrane and CINAHL was performed using combinations of the following keywords: 'dislocation', 'Rockwood', 'type three', 'treatment', 'acromioclavicular' and 'joint'. Fourteen studies were included, evaluating 646 shoulders. The rate of recurrence in the surgical group was 14%. No statistical significant differences were found between conservative and surgical approaches in terms of postoperative osteoarthritis and persistence of pain, although persistence of pain seemed to occur less frequently in patients undergoing a surgical treatment. Persistence of pain seemed to occur less frequently in patients undergoing surgery. Persistence of pain seems to occur less frequently in patients treated surgically for a Type III AC dislocation. There is insufficient evidence to establish the effects of surgical versus conservative treatment on functional outcome of patients with AC dislocation. High-quality randomized controlled clinical trials are needed to establish whether there is a difference in functional outcome. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  10. Acromioclavicular dislocation: treatment and rehabilitation. Current perspectives and trends among Brazilian orthopedists.

    Science.gov (United States)

    Arliani, Gustavo Gonçalves; Utino, Artur Yudi; Nishimura, Eduardo Misao; Terra, Bernardo Barcellos; Belangero, Paulo Santoro; Astur, Diego Costa

    2015-01-01

    To evaluate the approaches and procedures used by Brazilian orthopedic surgeons in treatment and rehabilitation of acromioclavicular dislocation of the shoulder. A questionnaire comprising eight closed questions that addressed topics relating to treatment and rehabilitation of acromioclavicular dislocation was applied to Brazilian orthopedic surgeons over the three days of the 45th Brazilian Congress of Orthopedics and Traumatology, in 2013. A total of 122 surgeons completely filled out the questionnaire and formed part of the sample analyzed. Most of them came from the southeastern region of the country. In this sample, 67% of the participants would choose surgical treatment for patients with grade 3 acromioclavicular dislocation. Regarding the preferred technique for surgical treatment of acute acromioclavicular dislocation, a majority of the surgeons used subcoracoid ligature with acromioclavicular fixation and transfer of the coracoacromial ligament (25.4%). Regarding complications found after surgery had been performed, 43.4% and 32.8% of the participants, respectively, stated that residual deformity of the operated joint and pain were the complications most seen during the postoperative period. Although there was no consensus regarding the treatment and rehabilitation of acromioclavicular dislocation, evolution had occurred in some of the topics analyzed in this questionnaire applied to Brazilian orthopedists. However, further controlled prospective studies are needed in order to evaluate the clinical and scientific benefit of these trends.

  11. Pattern of fractures and dislocations in a tertiary care hospital, north east Karnataka

    Directory of Open Access Journals (Sweden)

    Bhaskara K, Padmanabha T S, Nandini T, Sindhu

    2014-11-01

    Full Text Available Background: Trauma including accidents are today’s world concern forming a major non-communicable epidemic accounting for mortality and morbidity. The aim of the study was to determine and account the types of fractures and dislocations presented to Bidar Institute of Medical Sciences (BRIMS, Bidar, Karnataka, India. Methods and Material: This study is of retrospective in nature with a review of hospital inpatient case sheets of orthopaedic department in our hospital presented between July 2011 to Dec 2011. The data gathered was analysed by percentages. Results: Out of 132 cases analysed males (82.56%, outnumbered female (17.42%; 67.42 % of cases were between 18-45 years age group; femur (22.17 % was the most commonly involved bone followed by tibia (13.21%, foot (10.85%; tibia & fibular (8.96% involvement. Less common were spine (0.47%, vertebra (0.94% and scapula (0.94%. Fracture-dislocation was more common in lower limb (59.91% – ankle joint was most common-50% compared to upper limb (30.66%- shoulder joint: 12.5%. Conclusions: Among of 132 cases admitted 212 fractures & dislocation was noted. Male (82.56% was more common than females (17.42%. Age group most commonly involved was between 18-45 years (67.42%. Fracture was more common in femur (22.17% & dislocation was common in hip (42.86% because of high velocity injury. Approach towards the prevention of accidents by effective safety education, good roads and early intervention which is the need of the hour. Effective drugs should be made available in the casuality so that crush injuries are managed without complications like septicemia and tetanus.

  12. Canonical Quantization of Crystal Dislocation and Electron-Dislocation Scattering in an Isotropic Media

    Science.gov (United States)

    Li, Mingda; Cui, Wenping; Dresselhaus, M. S.; Chen, Gang; MIT Team; Boston College Team

    Crystal dislocations govern the plastic mechanical properties of materials but also affect the electrical and optical properties. However, a fundamental and decent quantum-mechanical theory of dislocation remains undiscovered for decades. Here we present an exact and manageable Hamiltonian theory for both edge and screw dislocation line in an isotropic media, where the effective Hamiltonian of a single dislocation line can be written in a harmonic-oscillator-like form, with closed-form quantized 1D phonon-like excitation. Moreover a closed-form, position dependent electron-dislocation coupling strength is obtained, from which we obtained good agreement of relaxation time when comparing with classical results. This Hamiltonian provides a platform to study the effect of dislocation to materials' non-mechanical properties from a fundamental Hamiltonian level.

  13. "Conjugate channeling" effect in dislocation core diffusion: carbon transport in dislocated BCC iron.

    Science.gov (United States)

    Ishii, Akio; Li, Ju; Ogata, Shigenobu

    2013-01-01

    Dislocation pipe diffusion seems to be a well-established phenomenon. Here we demonstrate an unexpected effect, that the migration of interstitials such as carbon in iron may be accelerated not in the dislocation line direction ξ, but in a conjugate diffusion direction. This accelerated random walk arises from a simple crystallographic channeling effect. c is a function of the Burgers vector b, but not ξ, thus a dislocation loop possesses the same everywhere. Using molecular dynamics and accelerated dynamics simulations, we further show that such dislocation-core-coupled carbon diffusion in iron has temperature-dependent activation enthalpy like a fragile glass. The 71° mixed dislocation is the only case in which we see straightforward pipe diffusion that does not depend on dislocation mobility.

  14. Distribution of distances between dislocations in different types of dislocation substructures in deformed Cu-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Trishkina, L., E-mail: trishkina.53@mail.ru; Zboykova, N.; Koneva, N., E-mail: koneva@tsuab.ru; Kozlov, E. [Tomsk State University of Architecture and Building, 2 Solyanaya St., Tomsk, 634003 (Russian Federation); Cherkasova, T. [Tomsk State University of Architecture and Building, 2 Solyanaya St., Tomsk, 634003 (Russian Federation); National Research Tomsk Polytechnic University, 50 Lenin Ave., Tomsk, 634050 (Russian Federation)

    2016-01-15

    The aim of the investigation was the determination of the statistic description of dislocation distribution in each dislocation substructures component forming after different deformation degrees in the Cu-Al alloys. The dislocation structures were investigated by the transmission diffraction electron microscopy method. In the work the statistic description of distance distribution between the dislocations, dislocation barriers and dislocation tangles in the deformed Cu-Al alloys with different concentration of Al and test temperature at the grain size of 100 µm was carried out. It was established that the above parameters influence the dislocation distribution in different types of the dislocation substructures (DSS): dislocation chaos, dislocation networks without disorientation, nondisoriented and disoriented cells, in the walls and inside the cells. The distributions of the distances between dislocations in the investigated alloys for each DSS type formed at certain deformation degrees and various test temperatures were plotted.

  15. Distribution of distances between dislocations in different types of dislocation substructures in deformed Cu-Al alloys

    Science.gov (United States)

    Trishkina, L.; Cherkasova, T.; Zboykova, N.; Koneva, N.; Kozlov, E.

    2016-01-01

    The aim of the investigation was the determination of the statistic description of dislocation distribution in each dislocation substructures component forming after different deformation degrees in the Cu-Al alloys. The dislocation structures were investigated by the transmission diffraction electron microscopy method. In the work the statistic description of distance distribution between the dislocations, dislocation barriers and dislocation tangles in the deformed Cu-Al alloys with different concentration of Al and test temperature at the grain size of 100 µm was carried out. It was established that the above parameters influence the dislocation distribution in different types of the dislocation substructures (DSS): dislocation chaos, dislocation networks without disorientation, nondisoriented and disoriented cells, in the walls and inside the cells. The distributions of the distances between dislocations in the investigated alloys for each DSS type formed at certain deformation degrees and various test temperatures were plotted.

  16. Tailoring Superconductivity with Quantum Dislocations.

    Science.gov (United States)

    Li, Mingda; Song, Qichen; Liu, Te-Huan; Meroueh, Laureen; Mahan, Gerald D; Dresselhaus, Mildred S; Chen, Gang

    2017-08-09

    Despite the established knowledge that crystal dislocations can affect a material's superconducting properties, the exact mechanism of the electron-dislocation interaction in a dislocated superconductor has long been missing. Being a type of defect, dislocations are expected to decrease a material's superconducting transition temperature (T c ) by breaking the coherence. Yet experimentally, even in isotropic type I superconductors, dislocations can either decrease, increase, or have little influence on T c . These experimental findings have yet to be understood. Although the anisotropic pairing in dirty superconductors has explained impurity-induced T c reduction, no quantitative agreement has been reached in the case a dislocation given its complexity. In this study, by generalizing the one-dimensional quantized dislocation field to three dimensions, we reveal that there are indeed two distinct types of electron-dislocation interactions. Besides the usual electron-dislocation potential scattering, there is another interaction driving an effective attraction between electrons that is caused by dislons, which are quantized modes of a dislocation. The role of dislocations to superconductivity is thus clarified as the competition between the classical and quantum effects, showing excellent agreement with existing experimental data. In particular, the existence of both classical and quantum effects provides a plausible explanation for the illusive origin of dislocation-induced superconductivity in semiconducting PbS/PbTe superlattice nanostructures. A quantitative criterion has been derived, in which a dislocated superconductor with low elastic moduli and small electron effective mass and in a confined environment is inclined to enhance T c . This provides a new pathway for engineering a material's superconducting properties by using dislocations as an additional degree of freedom.

  17. Low-Energy Traumatic Obturator Hip Dislocation with Ipsilateral Femoral Shaft Fracture in a Patient with Omolateral Knee Arthroplasty

    Directory of Open Access Journals (Sweden)

    G. Gazzotti

    2016-01-01

    Full Text Available Ipsilateral obturator hip dislocation and femoral shaft fracture are rare. We report such a case in an older woman after a low-energy injury. She had a knee prostheses in the same limb. The patient was treated by open manipulative reduction of the luxation without opening joint and open reduction and internal fixation of the femur with angular stability plate and screws. We could not find a similar case in the literature. An early diagnosis of the dislocation is crucial in order to obtain good results. Great awareness and radiologic examination are fundamental to achieve precocious diagnosis of both these rare combined injuries, as treatment in these cases is considered an emergency. The first step was an attempt to reduce the dislocation by closed means but it failed. Then we performed a short approach at the trochanteric region and used Lambotte forceps to manoeuvre the proximal femur without opening the joint achieving reduction. Thereafter the femoral shaft fracture underwent open reduction and internal fixation with an angular stable plate. After a 2-year follow-up the outcome was very good.

  18. A Novel Surgical Technique for Fixation of Recurrent Acromioclavicular Dislocations: AC Dog Bone Technique in Combination with Autogenous Semitendinosus Tendon Graft

    Directory of Open Access Journals (Sweden)

    Patrick Holweg

    2017-01-01

    Full Text Available Various surgical techniques have been described for the fixation of acromioclavicular (AC dislocations. However, recurrent dislocation is one of the main complications associated with the majority of these techniques. We report a case of postoperative AC joint redislocation. In order to overcome recurrent dislocation after revision surgery, a reconstruction of the conoid and trapezoid ligament with the use of a free tendon graft in combination with a FiberTape was provided within a novel surgical technique. After 12 months, the patient was very satisfied with the functional outcome. The patient achieved excellent results in the Constant (98 points, SPADI (0 points, and QuickDASH score (0 points. The described technique results in an anatomic reconstruction of the AC joint. The nonrigid nature of the intervention seems to restore the normal arthrokinematics by reconstructing the coracoclavicular ligaments with an autograft which is then protected by the AC Dog Bone artificial ligaments during the healing period. The arthroscopic approach to the AC joint with minimal exposure reduces the risks and complications of the intervention. This is the first case in literature that utilizes the artificial dog bone ligament securing the autograft in an anatomic AC reconstruction.

  19. Video Analysis of Primary Shoulder Dislocations in Rugby Tackles.

    Science.gov (United States)

    Maki, Nobukazu; Kawasaki, Takayuki; Mochizuki, Tomoyuki; Ota, Chihiro; Yoneda, Takeshi; Urayama, Shingo; Kaneko, Kazuo

    2017-06-01

    Characteristics of rugby tackles that lead to primary anterior shoulder dislocation remain unclear. To clarify the characteristics of tackling that lead to shoulder dislocation and to assess the correlation between the mechanism of injury and morphological damage of the glenoid. Case series; Level of evidence, 4. Eleven elite rugby players who sustained primary anterior shoulder dislocation due to one-on-one tackling between 2001 and 2014 were included. Using an assessment system, the tackler's movement, posture, and shoulder and head position were evaluated in each phase of tackling. Based on 3-dimensional computed tomography, the glenoid of the affected shoulder was classified into 3 types: intact, erosion, and bone defect. Orientation of the glenoid defect and presence of Hill-Sachs lesion were also evaluated. Eleven tackles that led to primary shoulder dislocation were divided into hand, arm, and shoulder tackle types based on the site at which the tackler contacted the ball carrier initially. In hand and arm tackles, the tackler's shoulder joint was forcibly moved to horizontal abduction by the impact of his upper limb, which appeared to result from an inappropriate approach to the ball carrier. In shoulder tackles, the tackler's head was lowered and was in front of the ball carrier at impact. There was no significant correlation between tackle types and the characteristics of bony lesions of the shoulder. Although the precise mechanism of primary anterior shoulder dislocation could not be estimated from this single-view analysis, failure of individual tackling leading to injury is not uniform and can be caused by 2 main factors: failure of approach followed by an extended arm position or inappropriate posture of the tackler at impact, such as a lowered head in front of the opponent. These findings indicate that injury mechanisms should be assessed for each type of tackle, as it is unknown whether external force to the glenoid is different in each mechanism

  20. Autologous blood injection to the temporomandibular joint: magnetic resonance imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Candirili, Celal; Yuece, Serdar; Cavus, Umut Yuecel; Akin, Kayihan; Cakir, Banu [Fatih University Hospital, Ankara (Turkmenistan)

    2012-03-15

    The aim of this study was to investigate the effect of the autologous blood injection (ABI) for chronic recurrent temporomandibular joint (TMJ) dislocation using magnetic resonance imaging (MRI). ABI was applied to 14 patients who had chronic recurrent TMJ dislocation. MRIs of the patients were taken and compared before and one month after the injection. All of the patients had no dislocations of their TMJs on clinical examination one month after the injection. In the pre-injection, unilateral or bilateral TMJ dislocations were observed on MRIs in all patients. One month after the injection, TMJ dislocations were not observed in MRI evaluation of any patients. A significant structural change that caused by ABI was not observed. The procedure was easy to perform and it caused no foreign body reaction. However, it was unclear how the procedure prevented the dislocation.

  1. Vastus Medialis advancement: clinical results and correlation with tangential X-rays of the patellofemoral joint

    International Nuclear Information System (INIS)

    O'Beirne, J.; O'Connell, R.J.; White, M.

    1986-01-01

    Thirteen patients who had recurrent dislocation of the patella treated by vastus medialis advancement were reviewed, and tangential X-rays of the patellofemoral joint were taken at the time of review. Clinically the results were excellent or good in ten (77%). However, the X-ray appearances were similar to what would be expected in a group of patients with untreated recurrent dislocation, probably because the corrective action of the vastus medialis did not apply with the quadriceps relaxed for X-ray. We conclude that vastus medialis advancement is a successful operation for recurrent patellar dislocation but that tangential X-rays of the patellofemoral joint are not an indicator of the outcome of surgery. (author)

  2. Dislocation Dynamics During Plastic Deformation

    CERN Document Server

    Messerschmidt, Ulrich

    2010-01-01

    The book gives an overview of the dynamic behavior of dislocations and its relation to plastic deformation. It introduces the general properties of dislocations and treats the dislocation dynamics in some detail. Finally, examples are described of the processes in different classes of materials, i.e. semiconductors, ceramics, metals, intermetallic materials, and quasicrystals. The processes are illustrated by many electron micrographs of dislocations under stress and by video clips taken during in situ straining experiments in a high-voltage electron microscope showing moving dislocations. Thus, the users of the book also obtain an immediate impression and understanding of dislocation dynamics.

  3. Trans-triquetral Perilunate fracture dislocation

    OpenAIRE

    John-Henry Rhind; Abhinav Gulihar; Andrew Smith

    2018-01-01

    Perilunate dislocations and perilunate fracture dislocations are rare and serious injuries. Perilunate dislocations represent less than 10% of all carpal injuries of which 61% represent transcaphoid fractures. Because of their rarity, up to 25% of perilunate dislocations are initially missed on first assessment. We present the case of a 66-year-old-gentleman who sustained an isolated trans-triquetral perilunate fracture dislocation while walking his dog. This was diagnosed in the emergency de...

  4. Autologous blood injection for treatment of chronic recurrent TMJ dislocation: is it successful? Is it safe enough? A systematic review.

    Science.gov (United States)

    Varedi, Payam; Bohluli, Behnam

    2015-09-01

    The purpose of this article is to review the English literature about the efficacy and safety of autologous blood injection in treating patients suffering from chronic recurrent temporomandibular joint dislocation. In this article, we highlight the key trials and recent directions about this modality and discuss about the mechanism, advantages, and disadvantages of this approach. A literature search was performed using PubMed, Medline, and Ovid Medline databases to identify articles reporting on the injection of autologous blood for treatment of chronic recurrent dislocation of temporomandibular joint. Other references cited in the retrieved reports, as well as the "related articles" tool in PubMed Medline, were also checked to improve the search and, if relevant, were included in the study. The search was restricted to articles published in the English language. Seven studies meeting the inclusion criteria were reviewed. The selected articles included four prospective clinical trials and three case report articles. There are a few articles about the clinical use of autologous blood for treating patients with chronic recurrent temporomandibular joint dislocation. Reviewing of the literature shows that there are successful results about this modality, but there are still some concerns about it in terms of the effect of the injected blood on the articular cartilage and formation of fibrous or bony ankylosis.

  5. Conservative treatment of an anterior-lateral ankle dislocation without an associated fracture in a diabetic patient: a case report

    Directory of Open Access Journals (Sweden)

    Panagiotis K. Karampinas

    2012-06-01

    Full Text Available Anterior or anterior-lateral dislocation of the ankle is a rare condition that can be treated conservatively as well as any other similar types of ankle dislocations without associated fractures. We present a case report of an anterior-lateral ankle dislocation with a concomitant avulsion injury of the ankle's anterior capsule in a diabetic patient that was treated conservatively. At the patient's visit 12 months after the initial injury, he was asymptomatic with full range of motion of the ankle joint. To our knowledge, we could not identify this type of an injury in a diabetic patient that was treated successfully with conservative treatment in the existing literature.

  6. A continuum theory of edge dislocations

    Science.gov (United States)

    Berdichevsky, V. L.

    2017-09-01

    Continuum theory of dislocation aims to describe the behavior of large ensembles of dislocations. This task is far from completion, and, most likely, does not have a "universal solution", which is applicable to any dislocation ensemble. In this regards it is important to have guiding lines set by benchmark cases, where the transition from a discrete set of dislocations to a continuum description is made rigorously. Two such cases have been considered recently: equilibrium of dislocation walls and screw dislocations in beams. In this paper one more case is studied, equilibrium of a large set of 2D edge dislocations placed randomly in a 2D bounded region. The major characteristic of interest is energy of dislocation ensemble, because it determines the structure of continuum equations. The homogenized energy functional is obtained for the periodic dislocation ensembles with a random contents of the periodic cell. Parameters of the periodic structure can change slowly on distances of order of the size of periodic cells. The energy functional is obtained by the variational-asymptotic method. Equilibrium positions are local minima of energy. It is confirmed the earlier assertion that energy density of the system is the sum of elastic energy of averaged elastic strains and microstructure energy, which is elastic energy of the neutralized dislocation system, i.e. the dislocation system placed in a constant dislocation density field making the averaged dislocation density zero. The computation of energy is reduced to solution of a variational cell problem. This problem is solved analytically. The solution is used to investigate stability of simple dislocation arrays, i.e. arrays with one dislocation in the periodic cell. The relations obtained yield two outcomes: First, there is a state parameter of the system, dislocation polarization; averaged stresses affect only dislocation polarization and cannot change other characteristics of the system. Second, the structure of

  7. The acromioclavicular joint: Normal variation and the diagnosis of dislocation

    International Nuclear Information System (INIS)

    Keats, T.E.; Pope, T.L. Jr.

    1988-01-01

    Acromioclavicular separation is a common traumatic injury. Diagnosis rests on clinical and radiographic findings. However, normal variation in the alignment of the acromioclavicular joint may make the roentgen diagnosis more difficult. We stress the variations of normal alignment at the acromioclavicular joint and offer suggestions for avoiding pitfalls in this clinical situation. (orig.)

  8. Ipsilateral Traumatic Posterior Hip Dislocation, Posterior Wall and Transverse Acetabular Fracture with Trochanteric Fracture in an adult: Report of First Case

    Directory of Open Access Journals (Sweden)

    Skand Sinha

    2013-10-01

    Full Text Available Introduction: Posterior dislocation of the hip joint with associated acetabular and intertrochanteric fracture is a complex injury. Early recognition, prompt and stable reduction is needed of successful outcome. Case Report: 45 year old male patient presented with posterior dislocation of the hip with transverse fracture with posterior wall fracture of acetabulam and intertrochanteric fracture on the ipsilateral side. The complex fracture geometry was confirmed by CT scan. The patient was successfully managed by open reduction and internal fixation of intertrochanteric fracture was achieved with dynamic hip screw (DHS plate fixation followed by fixation of acetabular fracture with reconstruction plate. Conclusion: Hip dislocation combined with acetabular fracture is an uncommon injury; this article presents a unique case of posterior wall and transverse fractures of ipsilateral acetabulum with intertrochanteric fracture in a patient who sustained traumatic posterior hip dislocation. Early surgical intervention is important for satisfactory outcomes of such complex fracture-dislocation injuries. Keywords: Hip dislocation; acetabular fractures; intertrochanteric fracture; operative treatment.

  9. Arthroscopically Assisted Reconstruction of Acute Acromioclavicular Joint Dislocations: Anatomic AC Ligament Reconstruction With Protective Internal Bracing—The “AC-RecoBridge” Technique

    Science.gov (United States)

    Izadpanah, Kaywan; Jaeger, Martin; Ogon, Peter; Südkamp, Norbert P.; Maier, Dirk

    2015-01-01

    An arthroscopically assisted technique for the treatment of acute acromioclavicular joint dislocations is presented. This pathology-based procedure aims to achieve anatomic healing of both the acromioclavicular ligament complex (ACLC) and the coracoclavicular ligaments. First, the acromioclavicular joint is reduced anatomically under macroscopic and radiologic control and temporarily transfixed with a K-wire. A single-channel technique using 2 suture tapes provides secure coracoclavicular stabilization. The key step of the procedure consists of the anatomic repair of the ACLC (“AC-Reco”). Basically, we have observed 4 patterns of injury: clavicular-sided, acromial-sided, oblique, and midportion tears. Direct and/or transosseous ACLC repair is performed accordingly. Then, an X-configured acromioclavicular suture tape cerclage (“AC-Bridge”) is applied under arthroscopic assistance to limit horizontal clavicular translation to a physiological extent. The AC-Bridge follows the principle of internal bracing and protects healing of the ACLC repair. The AC-Bridge is tightened on top of the repair, creating an additional suture-bridge effect and promoting anatomic ACLC healing. We refer to this combined technique of anatomic ACLC repair and protective internal bracing as the “AC-RecoBridge.” A detailed stepwise description of the surgical technique, including indications, technical pearls and pitfalls, and potential complications, is given. PMID:26052493

  10. Recessive multiple epiphyseal dysplasia (rMED with homozygosity for C653S mutation in the DTDST gene - Phenotype, molecular diagnosis and surgical treatment of habitual dislocation of multilayered patella: Case report

    Directory of Open Access Journals (Sweden)

    Bonafé Luisa

    2010-06-01

    Full Text Available Abstract Background Multiple epiphyseal dysplasia (MED is one of the more common generalised skeletal dysplasias. Due to its clinical heterogeneity diagnosis may be difficult. Mutations of at least six separate genes can cause MED. Joint deformities, joint pain and gait disorders are common symptoms. Case Presentation We report on a 27-year-old male patient suffering from clinical symptoms of autosomal recessive MED with habitual dislocation of a multilayered patella on both sides, on the surgical treatment and on short-term clinical outcome. Clinical findings were: bilateral hip and knee pain, instability of femorotibial and patellofemoral joints with habitual patella dislocation on both sides, contractures of hip, elbow and second metacarpophalangeal joints. Main radiographic findings were: bilateral dislocated multilayered patella, dysplastic medial tibial plateaus, deformity of both femoral heads and osteoarthritis of the hip joints, and deformity of both radial heads. In the molecular genetic analysis, the DTDST mutation g.1984T > A (p.C653S was found at the homozygote state. Carrier status was confirmed in the DNA of the patient's parents. The mutation could be considered to be the reason for the patient's disease. Surgical treatment of habitual patella dislocation with medialisation of the tibial tuberosity led to an excellent clinical outcome. Conclusions The knowledge of different phenotypes of skeletal dysplasias helps to select genes for genetic analysis. Compared to other DTDST mutations, this is a rather mild phenotype. Molecular diagnosis is important for genetic counselling and for an accurate prognosis. Even in case of a multilayered patella in MED, habitual patella dislocation could be managed successfully by medialisation of the tibial tuberosity.

  11. Unstable elbow dislocations: the description and cadaveric feasibility study of a new surgical technique

    Directory of Open Access Journals (Sweden)

    Harris Mark

    2015-01-01

    Full Text Available Introduction: A small proportion of simple elbow dislocations are grossly unstable and joint congruence is not maintained after reduction. In this rare situation operative treatment is indicated. We describe a new intra articular reconstruction that utilises a slip of triceps tendon to provide immediate stability to the elbow. Methods: We assessed 20 cadaveric elbows, measuring the length of triceps tendon available and required to complete the reconstruction. We then sequentially sectioned the ligamentous stabilisers of an elbow before performing the new technique. We measured the displacement and angulation possible at the elbow before and after the reconstruction. Results: All 20 elbows had sufficient triceps tendon length to complete the new technique. Prior to the reconstruction greater than 30 mm of joint distraction and 90 degrees varus or valgus angulation was possible. Following the reconstruction it was not possible to re-dislocate the elbow. Only 2 mm of joint distraction and 10 degrees of varus or valgus angulation were possible with the triceps graft fixed in position. Discussion: This novel technique elegantly avoids many of the problems associated with current methods. We have demonstrated that it is technically feasible and easy to perform with minimal equipment requirements or costs.

  12. Frenkel defect absorption on dislocations and dislocation discharge rate. Modeling determination of the absorption zone

    International Nuclear Information System (INIS)

    Mikhlin, Eh.Ya.

    1988-01-01

    A situation connected with the fact that evaluations of dislocation discharge strength which somehow or other are based on the elasticity theory in the dislocation nucleus or near it, do not lead to results complying with experimental data, is discussed. Bases of the alternative approach to this problem consisting in direct investigation into the process of Frenkel defect absorption on dislocation by its computerized simulation at the microscopic level are also presented. Methods of investigation and results are described using α dislocation in iron-alpha as an example. The concept of zones of vacancy and interstitial atom absorption on dislocation is discussed. It is shown that a spontaneous transition, performed by any of these defects near a dislocation is not always identical to absorption and usually appears to be only a part of a multistage process leading to the defect disappearance. Potential relief characteristics for vacancy movement near the dislocation are found. An area wide enough in a transverse direction is found around the dislocation. Vacncies reaching this area can be easily transported to places of their disappearance. Therefore the vacancy entry to this area is equivalent to the absorption. the procedure of simulating the atomic structure of a crystallite containing a dislocation with a step is described. Positions from which these defects perform spontaneous transitions, reaching the disappearance places are found on the dislocation near the step

  13. Glide Dislocations Dissociation in Inversion Domain Boundaries of Plastically Deformed Aluminium Nitride

    Science.gov (United States)

    Feregotto, Virginia; Michel, Jean-Pierre

    1996-09-01

    A ten per cent plastic deformation of polycrystalline aluminium nitride, at a temperature ranging from 1500 to 1650 ^{circ}C creates a new kind of intragranular defect. Observed by transmission electron microscopy, the look like torsion subboundaries created by dislocations with 1/3plastique de 10 % de nitrure d'aluminium polycristallin, entre 1500 et 1650 ^{circ}C introduit un nouveau type de défauts intragranulaires. Au microscope électronique par transmission, ils apparaissent comme des sous-joints de torsion créés par des dislocations de vecteurs de Burgers 1/3<~ngle11bar{2}0rangle dont les nœuds triples sont dissociés en partielles de Shockley ; ils sont situés dans le plan de base. En fait, ces défauts ne se produisent que sur les parties planes de défauts originels, les parois de domaines d'inversion. La formation de ces réseaux fautés est analysée comme l'ultime stade des interactions entre parois de domaines d'inversion et dislocations de glissement.

  14. Acromioclavicular Joint Fixation Using an Acroplate Combined With a Coracoclavicular Screw

    Science.gov (United States)

    Tavakoli Darestani, Reza; Ghaffari, Arash; Hosseinpour, Mehrdad

    2013-01-01

    Background Appropriate treatment of acromioclavicular joint dislocation is controversial. Acroplate fixation is one of the most common treatment methods of acromioclavicular joint (ACJ) dislocation. Based on the risk of re-dislocation after Acroplate fixation, we assumed that combined fixation with an Acroplate and a coracoclavicular screw helps improve the outcome. Objectives The main purpose of the current study was to compare the outcome of ACJ dislocation treated with an Acroplate alone and in combination with coracoclavicular screw. Patients and Methods This study was carried out on 40 patients with ACJ dislocation types III to VI who were divided randomly into two equal groups: Acroplate group (P) and Acroplate in combination with coracoclavicular screw group (P + S). The screws were extracted 3-6 months postoperatively. The patients were followed for 1 year and Imatani’s score was calculated. Finally, the data were compared between the groups. Results The mean Imatani’s score was significantly higher in P + S group (83.4 ± 14.1) than P group (81.2 ± 10.3) (P < 0.001). The mean duration of surgery was the same in the two groups (59.8 ± 9.4 minutes in group P V.s 64.3 ± 10.9 minutes in group P + S; P = 0.169). There were no cases of re-dislocation, degenerative changes and ossification and all patients returned to their previous jobs or sporting activities. Conclusions Using a coracoclavicular screw combined with an Acroplate can improve the patients’ function after ACJ disruption without any significant increase in surgical duration. Authors recommend this technique in the fixation of ACJ dislocation. PMID:24396788

  15. Irreducible Anterior Shoulder Dislocation Associated With Displaced Fracture of the Greater Tuberosity: An Analysis of Seven Cases

    Directory of Open Access Journals (Sweden)

    Morteza Nakhaei Amroodi

    2015-11-01

    Full Text Available Background: Although anterior shoulder dislocation is the most prevalent type of body dislocation, irreducible anterior shoulder dislocation is seldom reported in the literature, which is usually due to physical obstacles. Objectives: This study presents our findings regarding the causes of irreducibility of anterior shoulder dislocation associated with displaced fracture of the greater tuberosity. Patients and Methods: CT scans, open reduction of the joint, and internal fixation of the tuberosity was performed in seven patients with irreducible anterior shoulder dislocation associated with displaced fracture of the greater tuberosity. Results: As confirmed by intraoperative findings, the CT scans showed the cause of irreducible shoulder dislocation in six cases was the interposition of the long head of biceps (LHB in the anterior of the head that was displaced from the fracture line between the greater and lesser tuberosities. In another case, the greater and lesser tuberosities were attached to each other and were separated from the head. This fractured part was trapped. Conclusions: We suggest that performing CT scans in all cases of anterior shoulder dislocations with displaced fracture of the greater tuberosity can help surgeons to diagnose the accompanying fractures and possible complications, such as irreducibility. If the fracture line passes through the bicipital groove or in the case of a shield fracture, possible irreducibility should be borne in mind.

  16. Hand osteoarthritis: Differential diagnosis with inflammatory joint diseases and treatment policy

    Directory of Open Access Journals (Sweden)

    Yu. A. Olyunin

    2015-01-01

    Full Text Available Osteoarthritis (OA usually affects certain joint groups selectively and the hand joints (HJ are one of its classical locations. Hand OA is widespread in the population. In their practice rheumatologists encounter HJ injury in OA in 38% of cases. It is conventional to identify three main types of hand OA. These are 1 interphalangeal OA that may or may not be accompanied by nodulation; 2 first carpometacarpal OA; and 3 erosive OA. At the same time, the rate of clinical forms ranges from 2.0 to 6.2%; it is 4.7 to 20.4% in the elderly. Nonsteroidal antiinflammatory drugs (NSAIDs are most commonly used to relieve pain that is the main manifestation of the disease. The risk for NSAID-related adverse gastrointestinal (GI events is substantially reduced by the drugs that exert their effects mainly on cyclooxygenase 2. These include nimesulide in particular. Undesirable GI effects may be also considerably minimized by using NSAIDs that have both their gastroprotective and antiinflammatory activities. By suppressing pain and inflammatory changes, the recently designed NSAID amtolmetin guacil simultaneously exerts a protective effect on the GI mucosa, by elevating its nitric oxide levels.

  17. Hip dislocation following the treatment of femoral neck fracture: Case report

    Directory of Open Access Journals (Sweden)

    Vukašinović Zoran

    2010-01-01

    Full Text Available Introduction. Femoral neck fractures are very rare in young patients and are frequently complicated by femoral head osteonecrosis and femoral neck nonunion. Case Outline. A 19-year-old girl with hip dislocation following the treatment of the femoral neck fracture is presented. The femoral neck fracture was initially treated by open reduction and three-screw fixation. After detecting the nonunion of femoral neck, valgus osteotomy was done. Secondary, iatrogenic, hip dislocation appeared. The patient had pains, and in clinical findings a shorter leg and limited range of motion in the hip - altogether 40 degrees. She was then successfully treated by open reduction, together with Chiari pelvic osteotomy and joint transfixation. Transfixation pin was removed three weeks following the operation. After that, the patient was put into the abduction device and physical therapy was started. The mentioned regimen lasted four months after the surgery, then the abduction device was removed and walking started. Full weight bearing was allowed eight months after surgery. Conclusion. As we have not found the literature data concerning the above mentioned problem, we solved it in the way that we usually do for the treatment of developmental dislocation of the hip in adolescence.

  18. Differential diagnostics of different nosological forms of the temporomandibular joint pain dysfunction syndrome

    Directory of Open Access Journals (Sweden)

    Kameneva L.A.

    2014-09-01

    Full Text Available Research objective: to carry out differential diagnostics of various nosological forms of a temporal and temporomandibular joint pain dysfunction syndrome. Material and methods. On clinical base of orthopedic odontology chair of SamSMU inspection of 244 patients with temporomandibular joint pain dysfunction syndrome was performed. Diagnostics was carried out according to the special card of inspection which was developed on orthopedic odontology chair of SamSMU and included subjective, objective and special methods of research. As a result of research it is taped: 71 — an occlusal-articulation dysfunctional syndrome, 44 — a neuromuscular dysfunctional syndrome, 76 patients have a hardly set dislocation of intra joint disk and 53 — a habitual dislocation and a subluxation of a temporomandibular joint. We used Yu.A. Petrosov's classification as it displays most precisely the processes happening at pathology of the intra joint relations. Conclusion: On the basis of the obtained data the table of differential diagnostics of various nosological forms of temporomandibular joint pain dysfunction syndrome has been made.

  19. Numerical Simulation on Slabs Dislocation of Zipingpu Concrete Faced Rockfill Dam during the Wenchuan Earthquake Based on a Generalized Plasticity Model

    Directory of Open Access Journals (Sweden)

    Bin Xu

    2014-01-01

    Full Text Available After the Wenchuan earthquake in 2008, the Zipingpu concrete faced rockfill dam (CFRD was found slabs dislocation between different stages slabs and the maximum value reached 17 cm. This is a new damage pattern and did not occur in previous seismic damage investigation. Slabs dislocation will affect the seepage control system of the CFRD gravely and even the safety of the dam. Therefore, investigations of the slabs dislocation’s mechanism and development might be meaningful to the engineering design of the CFRD. In this study, based on the previous studies by the authors, the slabs dislocation phenomenon of the Zipingpu CFRD was investigated. The procedure and constitutive model of materials used for finite element analysis are consistent. The water elevation, the angel, and the strength of the construction joints were among major variables of investigation. The results indicated that the finite element procedure based on a modified generalized plasticity model and a perfect elastoplastic interface model can be used to evaluate the dislocation damage of face slabs of concrete faced rockfill dam during earthquake. The effects of the water elevation, the angel, and the strength of the construction joints are issues of major design concern under seismic loading.

  20. Mechanisms for decoration of dislocations by small dislocation loops under cascade damage conditions

    DEFF Research Database (Denmark)

    Trinkaus, H.; Singh, B.N.; Foreman, A.J.E.

    1997-01-01

    . This effect may arise as a result of either (a) migration and enhanced agglomeration of single SIAs in the form of loops in the strain field of the dislocation or (b) glide and trapping of SIA loops (produced directly in the cascades) in the strain field of the dislocation, In the present paper, both...... of these possibilities are examined. It is shown that the strain field of the dislocation causes a SIA depletion in the compressive as well as in the dilatational region resulting in a reduced rather than enhanced agglomeration of SIAs. (SIA depletion may, however, induce enhanced vacancy agglomeration near dislocations...

  1. Patella dislocation with vertical axis rotation: the "dorsal fin" patella.

    Science.gov (United States)

    Gamble, David; Otto, Quentin; Carrothers, Andrew D; Khanduja, Vikas

    2015-01-01

    A 44-year-old woman presented following minor trauma to her right knee. While dancing she externally rotated around a planted foot and felt sudden pain in her right knee. She presented with her knee locked in extension with a "dorsal fin" appearance of the soft tissues tented over the patella. This was diagnosed as a rare case of an intraarticular patella dislocation, which was rotated 90 degrees about the vertical axis. Closed reduction in the emergency room was unsuccessful but was achieved in theatre under general anaesthetic with muscle relaxation. Postreduction arthroscopy demonstrated that no osteochondral or soft tissue damage to the knee had been sustained. In patients presenting with a knee locked in extension with tenting of skin over the patella (the "dorsal fin" appearance), intra-articular patella dislocation should be suspected. Attempts to reduce vertical patella dislocations under sedation with excessive force or repeatedly without success should be avoided to prevent unnecessary damage to the patellofemoral joint. In this clinical situation we recommend closed reduction under general anaesthetic followed by immediate knee arthroscopy under the same anaesthetic to ensure that there is no chondral damage to the patella or femoral trochlea and to rule out an osteochondral fracture.

  2. Dislocation-cavity interaction in Fe: a comparison between molecular dynamics and dislocation dynamics

    International Nuclear Information System (INIS)

    Hafez Haghighat, S.M.; Schaeublin, R.; Fivel, M.C.

    2007-01-01

    Full text of publication follows: multi-scale modeling, including molecular dynamics (MD) and discrete dislocation dynamics (DDD) methods, appears as a significant tool for the description of plasticity and mechanical properties of materials. This research is on the investigation of the subsequence effects of irradiation on the plasticity of pure Fe and focuses on the interaction of a single dislocation and a spherical cavity, as void or He bubble. Extensive MD simulations of the interaction under imposed strain rate [1, 2] have shown that various temperatures and cavity sizes result in different release stresses depending on dislocation bow out. It appears that a temperature increase and cavity size decrease reduce the cavity strength. MD simulation shows that the elastic field around the cavity is largely anisotropic. This anisotropy may influence the way the dislocation unpins from the cavity. Following the MD simulations, the interaction of a single dislocation and a spherical cavity is now simulated using a DDD discrete dislocation dynamics model. The simulation accounts for the non-Schmidt effect induced by the bcc structure of Fe through local rules derived from MD simulations [3]. The cavity is introduced in the simulation by computing the image forces using a finite element technique. The effective stress applied on the dislocation is then obtained as the superimposition of the applied stress field, the image stress field and the internal stresses. Note that such a model only uses elasticity theory and no core effect of dislocations is taken into account. One of the objectives of this work is to check whether elasticity is responsible of the behaviour observed by MD. Several cases are tested. First an edge dislocation in a (110) plane is pushed against the cavity under a pure shear loading. The local reaction of the dislocations and the cavity are compared to the MD simulations. Then, the case of a screw dislocation is studied. Finally, other loading

  3. The temporomandibular joint

    International Nuclear Information System (INIS)

    Campbell, W.

    1984-01-01

    Whilst the temporomandibular joint is in many ways unique, it is subject to all the diseases and disorders found in joints in other parts of the human skeleton. By far the most common disorder is injury, followed by arthropathy, acute and chronic dislocations, ankylosis, and in rare instances, neoplasms. The diagnosis and management of the temporomandibular joint are the primary responsibility of the oral surgeon. Nevertheless, this anatomical region is an area in which the cooperation of medical and dental disciplines may be required for the satisfactory conclusion of treatment. The more so when the disease process involves either associated psychosomatic illness or malignancy. The mainstay of the diagnosis is a careful radiological examination of the joint. There exists a delicate relationship between the dentition, the muscles of mastication, and the temporomandibular articulation, which is controlled by arthrokinetic reflex activity of the branches of the 5th cranial nerve. Imbalance between one or more of the components of this integrated system frequently leads to disturbances in function. Pain-dysfunction disorders constitute the larger part of temporomandibular joint disturbances generally encountered

  4. Neural network based automated algorithm to identify joint locations on hand/wrist radiographs for arthritis assessment

    International Nuclear Information System (INIS)

    Duryea, J.; Zaim, S.; Wolfe, F.

    2002-01-01

    Arthritis is a significant and costly healthcare problem that requires objective and quantifiable methods to evaluate its progression. Here we describe software that can automatically determine the locations of seven joints in the proximal hand and wrist that demonstrate arthritic changes. These are the five carpometacarpal (CMC1, CMC2, CMC3, CMC4, CMC5), radiocarpal (RC), and the scaphocapitate (SC) joints. The algorithm was based on an artificial neural network (ANN) that was trained using independent sets of digitized hand radiographs and manually identified joint locations. The algorithm used landmarks determined automatically by software developed in our previous work as starting points. Other than requiring user input of the location of nonanatomical structures and the orientation of the hand on the film, the procedure was fully automated. The software was tested on two datasets: 50 digitized hand radiographs from patients participating in a large clinical study, and 60 from subjects participating in arthritis research studies and who had mild to moderate rheumatoid arthritis (RA). It was evaluated by a comparison to joint locations determined by a trained radiologist using manual tracing. The success rate for determining the CMC, RC, and SC joints was 87%-99%, for normal hands and 81%-99% for RA hands. This is a first step in performing an automated computer-aided assessment of wrist joints for arthritis progression. The software provides landmarks that will be used by subsequent image processing routines to analyze each joint individually for structural changes such as erosions and joint space narrowing

  5. MRI after patellar dislocation. Assessment of risk factors and injury to the joint; MRT nach Patellaluxation. Quantifizierung der Risikofaktoren und Beschreibung der Folgeschaeden

    Energy Technology Data Exchange (ETDEWEB)

    Diederichs, G. [Charite Universitaetsmedizin, Berlin (Germany). Radiologie; Scheffler, S. [Charite Universitaetsmedizin, Berlin (Germany). Zentrum fuer Muskuloskeletale Chirurgie; Chirurgisch Orthopaedischer PraxisVerbund, Berlin (Germany)

    2013-07-15

    Patellar dislocation is the lateral displacement of the patella from the femoral trochlea. Affected individuals typically have underlying anatomic risk factors of variable magnitude, which, in conjunction with leg rotation, cause the event. Magnetic resonance imaging (MRI) permits straightforward diagnosis of the typical features of recent patellar dislocation: contusion edema of the inferomedial patella and the lateral femoral condyle as well as rupture of the medial patellofemoral ligament. In case of concomitant osteochondral injury, early surgical refixation may be indicated, depending on the size. After a first dislocation, which can damage the capsuloligamentous stabilizers, subjects may sustain further dislocations or even develop chronic patellofemoral instability, depending on the presence and severity of anatomic variants. A wide range of conservative and surgical treatments are available. While a first patellar dislocation is often treated conservatively, surgical strategies after a second dislocation depend on the pattern of injury and the severity of underlying anatomic risk factors. The most relevant predisposing variants are trochlear dysplasia, patella alta, and an abnormal tibial tubercle to trochlear groove distance (TT-TG). The radiologist's report should give a quantitative estimate of both the injuries resulting from dislocation and the underlying anatomic risk factors. An accurate characterization of the individual pathomechanism is crucial for tailoring treatment. (orig.)

  6. Discrete dislocation modelling of submicron indentation

    NARCIS (Netherlands)

    Widjaja, A; Van der Giessen, E; Needleman, A

    2005-01-01

    Indentation of a planar single crystal by a circular rigid indenter is analyzed using discrete dislocation plasticity. The crystal has three slip systems and is initially dislocation-free, but edge dislocations can nucleate from point sources inside the crystal. The lattice resistance to dislocation

  7. [Outcomes and complications of Tightrope button plate for repairing acromioclavicular dislocation].

    Science.gov (United States)

    Zuo, Yong-Xiang; Ma, Zi-Ping

    2017-10-25

    To study the clinical outcome and complications of Tightrope button plate for repairing acromioclavicular dislocation of Rockwood type III to V. From May 2014 to December 2016, 17 patients with acromioclavicular dislocation of type III-V were treated with Tightrope button plate including 10 males and 7 females with an average age 39.8 years old ranging from 20 to 68 years old. Four patients were treated with arthroscopy and 17 patients were treated with mini-invasive by X-ray assisted. Shoulder function, X-ray and complications after operation were assessed. All patients were followed up for 5 to 23 months with a mean of 10.8 months. All patients got satisfying reduction immediately postoperatively. Among them, 1 case of clavicle end wound foreign body reaction, rupture, effusion, healing after the second suture; 1 case of foreign body granuloma formation at the end of clavicle were resected and removed at 4 months after operation; 3 cases loss reduction(less than 50% of acromioclavicular joint). No coracoid fracture and suture breakage observed. The shoulder mobility was restored in 15 cases at 4 to 6 weeks postoperatively, and the shoulder adhesion in 2 cases was delayed to 5 to 7 months after operation. The Constant scores were improved from 46.9±6.0 preoperatively to 92.7±4.0 at the final follow-up. X-ray evaluation of postoperative coracoclavicular tunnel location, patients' coracoclavicular tunnel with mini-invasive fluoroscopy all closed to the ideal position (across the clavicle vertically through the coracoid base center), while different degree of tunnel position deviation were observed in arthroscopic patients. Tightrope button plate for the treatment of acromioclavicular joint dislocation had advantages of minimally invasive, effective, good clinical results, the majority of common complications does not affect efficacy. Small incision X-ray method can provide more satisfactory and reliable tunnel location.

  8. Dislocated Shoulder: Symptoms and Causes

    Science.gov (United States)

    ... caused by: Sports injuries. Shoulder dislocation is a common injury in contact sports, such as football and hockey, and in sports that may involve falls, such as downhill skiing, gymnastics and volleyball. ... is a common source of dislocation. Falls. You may dislocate your ...

  9. Microscopically derived free energy of dislocations

    NARCIS (Netherlands)

    Kooiman, M.; Hütter, M.; Geers, M.G.D.

    2015-01-01

    The dynamics of large amounts of dislocations is the governing mechanism in metal plasticity. The free energy of a continuous dislocation density profile plays a crucial role in the description of the dynamics of dislocations, as free energy derivatives act as the driving forces of dislocation

  10. Effects of dislocations on polycrystal anelasticity

    Science.gov (United States)

    Sasaki, Y.; Takei, Y.; McCarthy, C.; Suzuki, A.

    2017-12-01

    Effects of dislocations on the seismic velocity and attenuation have been poorly understood, because only a few experimental studies have been performed [Guéguen et al., 1989; Farla et al., 2012]. By using organic borneol as a rock analogue, we measured dislocation-induced anelasticity accurately over a broad frequency range. We first measured the flow law of borneol aggregates by uniaxial compression tests under a confining pressure of 0.8 MPa. A transition from diffusion creep (n = 1) to dislocation creep (n = 5) was captured at about σ = 1 MPa (40°C-50°C). After deforming in the dislocation creep regime, sample microstructure showed irregular grain shape consistent with grain boundary migration. Next, we conducted three creep tests at σ = 0.27 MPa (diffusion creep regime), σ = 1.3 MPa and σ = 1.9 MPa (dislocation creep regime) on the same sample in increasing order, and measured Young's modulus E and attenuation Q-1 after each creep test by forced oscillation tests. The results show that as σ increased, E decreased and Q-1 increased. These changes induced by dislocations, however, almost fully recovered during the forced oscillation tests performed for about two weeks under a small stress (σ = 0.27 MPa) due to the dislocation recovery (annihilation). In order to constrain the time scale of the dislocation-induced anelastic relaxation, we further measured Young's modulus E at ultrasonic frequency before and after the dislocation creep and found that E at 106 Hz is not influenced by dislocations. Because E at 100 Hz is reduced by dislocations by 10%, the dislocation-induced anelastic relaxation occurs mostly between 102-106 Hz which is at a higher frequency than grain-boundary-induced anelasticity. To avoid dislocation recovery during the anelasticity measurement, we are now trying to perform an in-situ measurement of anelasticity while simultaneously deforming under a high stress associated with dislocation creep. The combination of persistent creep

  11. Traumatic hip dislocations in children

    International Nuclear Information System (INIS)

    Minhas, M.S.

    2010-01-01

    Objectives: To evaluate clinical features, treatment and relationship to the time period between dislocation, reduction and early complications of traumatic dislocation of hip in children. Methods: Case series conducted at Jinnah Post Graduate Medical Centre Karachi from July 2005 to August 2009. Children with traumatic hip dislocation up to fifteen years of age who presented in last four years were included in this study. Their clinical information, etiology, associated injuries, duration, method of reduction and early complications are evaluated through emergency room proforma and indoor record. Follow up of patient was updated in outpatient department. Results: We had eight patients, six boys and two girls. Youngest 2.4 years and eldest was 12 years with mean age of 6.2 +- 3.8 years. All presented with posterior hip dislocation. Etiology was road traffic accident in two and history of fall in remaining six patients. Average duration of time between dislocation and reduction was 19 hours range 3-72 hours. Dislocated hips were reduced under General Anaesthesia in two patients and under sedation analgesia in six patients. No complications were noted in eight cases with mean 18.75 +- 13.23 months follows up. Conclusion: Traumatic hip dislocation in children is not rare. Slight trauma causes dislocation in younger age and immediate closed reduction and Immobilization reduces complications. (author

  12. Anatomical principles for minimally invasive reconstruction of the acromioclavicular joint with anchors.

    Science.gov (United States)

    Xiong, Chuanzhi; Lu, Yaojia; Wang, Qiang; Chen, Gang; Hu, Hansheng; Lu, Zhihua

    2016-11-01

    The aim of this study was to evaluate the outcome of a minimally invasive surgical technique for the treatment of patients with acromioclavicular joint dislocation. Sixteen patients with complete acromioclavicular joint dislocation were enrolled in this study. All patients were asked to follow the less active rehabilitation protocol post-operatively. Computed tomography with 3-D reconstruction of the injured shoulder was performed on each patient post operatively for the assessment of the accuracy of the suture anchor placement in the coracoid process and the reduction of the acromioclavicular joint. Radiographs of Zanca view and axillary view of both shoulders were taken for evaluating the maintenance of the acromioclavicular joint reduction at each follow-up visit. The Constant shoulder score was used for function assessment at the final follow-up. Twenty seven of the 32 anchors implanted in the coracoid process met the criteria of good position. One patient developed complete loss of reduction and another had partial loss of reduction in the anteroposterior plane. For the other 14 patients, the mean Constant score was 90 (range, 82-95). For the patients with partial and complete loss of reduction, the Constant score were 92 and 76 respectively. All of them got nearly normal range of motion of the shoulders and restored to pre-operative life and works. With this minimally invasive approach and limited exposure of the coracoid, a surgeon can place the suture anchors at the anatomical insertions of the coracoclavicular ligament and allow the dislocated joint reduced and maintained well. Level IV, Case series; therapeutic study.

  13. Recombination properties of dislocations in GaN

    Science.gov (United States)

    Yakimov, Eugene B.; Polyakov, Alexander Y.; Lee, In-Hwan; Pearton, Stephen J.

    2018-04-01

    The recombination activity of threading dislocations in n-GaN with different dislocation densities and different doping levels was studied using electron beam induced current (EBIC). The recombination velocity on a dislocation, also known as the dislocation recombination strength, was calculated. The results suggest that dislocations in n-GaN giving contrast in EBIC are charged and surrounded by a space charge region, as evidenced by the observed dependence of dislocation recombination strength on dopant concentration. For moderate (below ˜108 cm-2) dislocation densities, these defects do not primarily determine the average diffusion length of nonequilibrium charge carriers, although locally, dislocations are efficient recombination sites. In general, it is observed that the effect of the growth method [standard metalorganic chemical vapor deposition (MOCVD), epitaxial lateral overgrowth versions of MOCVD, and hydride vapor phase epitaxy] on the recombination activity of dislocations is not very pronounced, although the average diffusion lengths can widely differ for various samples. The glide of basal plane dislocations at room temperature promoted by low energy electron irradiation does not significantly change the recombination properties of dislocations.

  14. Quasicontinuum analysis of dislocation-coherent twin boundary interaction to provide local rules to discrete dislocation dynamics

    Science.gov (United States)

    Tran, H.-S.; Tummala, H.; Duchene, L.; Pardoen, T.; Fivel, M.; Habraken, A. M.

    2017-10-01

    The interaction of a pure screw dislocation with a Coherent Twin Boundary Σ3 in copper was studied using the Quasicontinuum method. Coherent Twin Boundary behaves as a strong barrier to dislocation glide and prohibits slip transmission across the boundary. Dislocation pileup modifies the stress field at its intersection with the Grain Boundary (GB). A methodology to estimate the strength of the barrier for a dislocation to slip across CTB is proposed. A screw dislocation approaching the boundary from one side either propagates into the adjacent twin grain by cutting through the twin boundary or is stopped and increases the dislocation pileup amplitude at the GB. Quantitative estimation of the critical stress for transmission was performed using the virial stress computed by Quasicontinuum method. The transmission mechanism and critical stress are in line with the literature. Such information can be used as input for dislocation dynamic simulations for a better modeling of grain boundaries.

  15. Hybrid dislocated control and general hybrid projective dislocated synchronization for the modified Lue chaotic system

    International Nuclear Information System (INIS)

    Xu Yuhua; Zhou Wuneng; Fang Jianan

    2009-01-01

    This paper introduces a modified Lue chaotic system, and some basic dynamical properties are studied. Based on these properties, we present hybrid dislocated control method for stabilizing chaos to unstable equilibrium and limit cycle. In addition, based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization (GHPDS) is proposed, which includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. The drive and response systems discussed in this paper can be strictly different dynamical systems (including different dimensional systems). As examples, the modified Lue chaotic system, Chen chaotic system and hyperchaotic Chen system are discussed. Numerical simulations are given to show the effectiveness of these methods.

  16. Hybrid dislocated control and general hybrid projective dislocated synchronization for the modified Lue chaotic system

    Energy Technology Data Exchange (ETDEWEB)

    Xu Yuhua [College of Information Science and Technology, Donghua University, Shanghai 201620 (China) and Department of Maths, Yunyang Teacher' s College, Hubei 442000 (China)], E-mail: yuhuaxu2004@163.com; Zhou Wuneng [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)], E-mail: wnzhou@163.com; Fang Jianan [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)

    2009-11-15

    This paper introduces a modified Lue chaotic system, and some basic dynamical properties are studied. Based on these properties, we present hybrid dislocated control method for stabilizing chaos to unstable equilibrium and limit cycle. In addition, based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization (GHPDS) is proposed, which includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. The drive and response systems discussed in this paper can be strictly different dynamical systems (including different dimensional systems). As examples, the modified Lue chaotic system, Chen chaotic system and hyperchaotic Chen system are discussed. Numerical simulations are given to show the effectiveness of these methods.

  17. Coarse-grained elastodynamics of fast moving dislocations

    International Nuclear Information System (INIS)

    Xiong, Liming; Rigelesaiyin, Ji; Chen, Xiang; Xu, Shuozhi; McDowell, David L.; Chen, Youping

    2016-01-01

    The fundamental mechanism of dynamic plasticity in metallic materials subjected to shock loading remains unclear because it is difficult to obtain the precise information of individual fast moving dislocations in metals from the state-of-the-art experiments. In this work, the dynamics of sonic dislocations in anisotropic crystalline materials is explored through a concurrent atomistic-continuum modeling method. We make a first attempt to characterize the complexity of nonuniformly moving dislocations in anisotropic crystals from atomistic to microscale, including the energy intensities as well as the wavelengths of acoustic phonons emitted from sonic dislocations, and the velocity-dependent stress fluctuations around the core of nonuniformly moving dislocations. Instantaneous dislocation velocities and phonon drag effects on the dislocation motions are quantified and analyzed. Mach cones in a V-shaped pattern of the phonon wave-fronts are observed in the wake of the sonic dislocations. Analysis of simulation results based on a wavelet transform show that the faster a dislocation is moving, the longer the emitted phonon wavelength. The dislocation velocity drops dramatically with the occurrence of the interactions between dislocations and phonon waves reflected from the boundaries of specimens. The concurrent atomistic-continuum modeling framework is demonstrated to be the first multiscale method that explicitly treats the strong coupling between the long-range elastic fields away from the dislocation core, the highly nonlinear time-dependent stress field within the core, and the evolutions of the atomic-scale dislocation core structures. As such, it is shown that this method is capable in predicting elastodynamics of dislocations in the presence of inertia effects associated with sonic dislocations in micron-sized anisotropic crystalline materials from the atomic level, which is not directly accessible to the recent elastodynamic discrete dislocation model.

  18. Joint Force Quarterly. Number 30, Spring 2002

    Science.gov (United States)

    2002-05-01

    Clemmons , USA ■ National War College A. Denis Clift ■ Joint Military Intelligence College RADM David R. Ellison, USN ■ Naval Postgraduate School BG Mark P...to determine the main axis of the German advance [General Maurice ] Gamelin dislocated his strategic reserves by committing the French Seventh Army to

  19. Theory of interacting dislocations on cylinders.

    Science.gov (United States)

    Amir, Ariel; Paulose, Jayson; Nelson, David R

    2013-04-01

    We study the mechanics and statistical physics of dislocations interacting on cylinders, motivated by the elongation of rod-shaped bacterial cell walls and cylindrical assemblies of colloidal particles subject to external stresses. The interaction energy and forces between dislocations are solved analytically, and analyzed asymptotically. The results of continuum elastic theory agree well with numerical simulations on finite lattices even for relatively small systems. Isolated dislocations on a cylinder act like grain boundaries. With colloidal crystals in mind, we show that saddle points are created by a Peach-Koehler force on the dislocations in the circumferential direction, causing dislocation pairs to unbind. The thermal nucleation rate of dislocation unbinding is calculated, for an arbitrary mobility tensor and external stress, including the case of a twist-induced Peach-Koehler force along the cylinder axis. Surprisingly rich phenomena arise for dislocations on cylinders, despite their vanishing Gaussian curvature.

  20. Effectiveness of intra-articular lidocaine injection for reduction of anterior shoulder dislocation: randomized clinical trial.

    Science.gov (United States)

    Tamaoki, Marcel Jun Sugawara; Faloppa, Flavio; Wajnsztejn, André; Archetti Netto, Nicola; Matsumoto, Marcelo Hide; Belloti, João Carlos

    2012-01-01

    Shoulder dislocation is the most common dislocation among the large joints. The aim here was to compare the effectiveness of reduction of acute anterior shoulder dislocation with or without articular anesthesia. Prospective randomized trial conducted in Escola Paulista de Medicina, Universidade Federal de São Paulo (EPM-Unifesp). From March 2008 to December 2009, 42 patients with shoulder dislocation were recruited. Reductions using traction-countertraction for acute anterior shoulder dislocation with and without lidocaine articular anesthesia were compared. As the primary outcome, pain was assessed through application of a visual analogue scale before reduction, and one and five minutes after the reduction maneuver was performed. Complications were also assessed. Forty-two patients were included: 20 in the group without analgesia (control group) and 22 in the group that received intra-articular lidocaine injection. The group that received intra-articular lidocaine had a statistically greater decrease in pain over time than shown by the control group, both in the first minute (respectively: mean 2.1 (0 to 5.0), standard deviation, SD 1.3, versus mean 4.9 (2.0 to 7.0, SD 1.5; P < 0.001) and the fifth minute (respectively: mean 1.0; 0 to 3.0; SD = 1.0 versus mean 4.0; 1.0 to 6.0; SD = 1.4; P < 0.001). There was one failure in the control group. There were no other complications in either group. Reduction of anterior shoulder dislocation using intra-articular lidocaine injection is effective, since it is safe and diminishes the pain. ISRCTN27127703.

  1. Patella Dislocation with Vertical Axis Rotation: The “Dorsal Fin” Patella

    Directory of Open Access Journals (Sweden)

    David Gamble

    2015-01-01

    Full Text Available A 44-year-old woman presented following minor trauma to her right knee. While dancing she externally rotated around a planted foot and felt sudden pain in her right knee. She presented with her knee locked in extension with a “dorsal fin” appearance of the soft tissues tented over the patella. This was diagnosed as a rare case of an intraarticular patella dislocation, which was rotated 90 degrees about the vertical axis. Closed reduction in the emergency room was unsuccessful but was achieved in theatre under general anaesthetic with muscle relaxation. Postreduction arthroscopy demonstrated that no osteochondral or soft tissue damage to the knee had been sustained. In patients presenting with a knee locked in extension with tenting of skin over the patella (the “dorsal fin” appearance, intra-articular patella dislocation should be suspected. Attempts to reduce vertical patella dislocations under sedation with excessive force or repeatedly without success should be avoided to prevent unnecessary damage to the patellofemoral joint. In this clinical situation we recommend closed reduction under general anaesthetic followed by immediate knee arthroscopy under the same anaesthetic to ensure that there is no chondral damage to the patella or femoral trochlea and to rule out an osteochondral fracture.

  2. Appearance of the temporomandibular joint after meniscoplasty on MR images

    International Nuclear Information System (INIS)

    Conway, W.F.; Hayes, C.W.; Campbell, R.L.; Laskin, D.M.

    1989-01-01

    Twenty-five postmeniscoplasty temporomandibular joints (TMJs) were studied in 20 patients. In all patients, preoperative MR images showed anteriorly dislocated disks. The patients underwent a similar postoperative MR examination 4-12 months after surgery. Surgical results were classified clinically as either poor, fair, good, or excellent at the time of the follow-up MR imaging. Forty percent of patients had good or excellent clinical results, and 60% had poor or fair results. The good/excellent group all had disks that appeared to be in normal or near normal position. Almost all disks were fixed in position. The degree of condylar translation was variable. The poor/fair group all had postoperative joints with anteriorly dislocated disks that were fixed in place. Recapture of the disk was variable, as was the degree of condylar translation

  3. Relaxation strain measurements in cellular dislocation structures

    International Nuclear Information System (INIS)

    Tsai, C.Y.; Quesnel, D.J.

    1984-01-01

    The conventional picture of what happens during a stress relaxation usually involves imagining the response of a single dislocation to a steadily decreasing stress. The velocity of this dislocation decreases with decreasing stress in such a way that we can measure the stress dependence of the dislocation velocity. Analysis of the data from a different viewpoint enables us to calculate the apparent activation volume for the motion of the dislocation under the assumption of thermally activated glie. Conventional thinking about stress relaxation, however, does not consider the eventual fate of this dislocation. If the stress relaxes to a low enough level, it is clear that the dislocation must stop. This is consistent with the idea that we can determine the stress dependence of the dislocation velocity from relaxation data only for those cases where the dislocation's velocity is allowed to approach zero asymptotically, in short, for those cases where the dislocation never stops. This conflict poses a dilemma for the experimentalist. In real crystals, however, obstacles impede the dislocation's progress so that those dislocations which are stopped at a given stress will probably never resume motion under the influence of the steadily declining stress present during relaxation. Thus one could envision stress relaxation as a process of exhaustion of mobile dislocations, rather than a process of decreasing dislocation velocity. Clearly both points of view have merit and in reality both mechanisms contribute to the phenomena

  4. Dislocation pinning effects induced by nano-precipitates during warm laser shock peening: Dislocation dynamic simulation and experiments

    Science.gov (United States)

    Liao, Yiliang; Ye, Chang; Gao, Huang; Kim, Bong-Joong; Suslov, Sergey; Stach, Eric A.; Cheng, Gary J.

    2011-07-01

    Warm laser shock peening (WLSP) is a new high strain rate surface strengthening process that has been demonstrated to significantly improve the fatigue performance of metallic components. This improvement is mainly due to the interaction of dislocations with highly dense nanoscale precipitates, which are generated by dynamic precipitation during the WLSP process. In this paper, the dislocation pinning effects induced by the nanoscale precipitates during WLSP are systematically studied. Aluminum alloy 6061 and AISI 4140 steel are selected as the materials with which to conduct WLSP experiments. Multiscale discrete dislocation dynamics (MDDD) simulation is conducted in order to investigate the interaction of dislocations and precipitates during the shock wave propagation. The evolution of dislocation structures during the shock wave propagation is studied. The dislocation structures after WLSP are characterized via transmission electron microscopy and are compared with the results of the MDDD simulation. The results show that nano-precipitates facilitate the generation of highly dense and uniformly distributed dislocation structures. The dislocation pinning effect is strongly affected by the density, size, and space distribution of nano-precipitates.

  5. Primary traumatic patellar dislocation

    Directory of Open Access Journals (Sweden)

    Tsai Chun-Hao

    2012-06-01

    Full Text Available Abstract Acute traumatic patellar dislocation is a common injury in the active and young adult populations. MRI of the knee is recommended in all patients who present with acute patellar dislocation. Numerous operative and non-operative methods have been described to treat the injuries; however, the ideal management of the acute traumatic patellar dislocation in young adults is still in debate. This article is intended to review the studies to the subjects of epidemiology, initial examination and management.

  6. Restoration of horizontal stability in complete acromioclavicular joint separations: surgical technique and preliminary results.

    Science.gov (United States)

    Li, Haoqing; Wang, Chuanshun; Wang, Jiandong; Wu, Kai; Hang, Donghua

    2013-11-13

    Our purpose was to investigate the clinical efficacy of arthroscope-assisted acromioclavicular ligament reconstruction in combination with double endobutton coracoclavicular ligament reconstruction for the treatment of complete acromioclavicular joint dislocation. During the period from February 2010 to October 2012, ten patients with Rockwood types IV and V acromioclavicular joint dislocation were hospitalized and nine were treated with acromioclavicular ligament reconstruction combined with double endobutton of coracoclavicular ligament reconstruction. The improvement in shoulder functions was assessed using a Constant score and visual analog scale (VAS) system. The mean follow-up period was 33.6 ± 5.4 months. The mean Constant scores improved from 25.2 ± 6.6 preoperatively to 92.4 ± 6.5 postoperatively, while the mean VAS score decreased from 5.9 ± 1.4 to 1.2 ± 0.9; significant differences were observed. The final follow-up revealed that excellent outcomes were achieved in eight patients and good outcome in two patients. Arthroscope-assisted acromioclavicular ligament reconstruction in combination with double endobutton of coracoclavicular ligament reconstruction is an effective approach for treatment of acute complete acromioclavicular joint dislocation.

  7. Stress-free states of continuum dislocation fields : Rotations, grain boundaries, and the Nye dislocation density tensor

    NARCIS (Netherlands)

    Limkumnerd, Surachate; Sethna, James P.

    We derive general relations between grain boundaries, rotational deformations, and stress-free states for the mesoscale continuum Nye dislocation density tensor. Dislocations generally are associated with long-range stress fields. We provide the general form for dislocation density fields whose

  8. Molecular dynamics simulation of dislocation intersections in aluminum

    International Nuclear Information System (INIS)

    Li, M.; Chu, W.Y.; Qian, C.F.; Gao, K.W.; Qiao, L.J.

    2003-01-01

    The molecular dynamics method is used to simulate dislocation intersection in aluminum containing 1.6x10 6 atoms using embedded atom method (EAM) potential. The results show that after intersection between two right-hand screw dislocations of opposite sign there are an extended jog corresponding to a row of 1/3 vacancies in the intersected dislocation, and a trail of vacancies behind the moving dislocation. After intersection between screw dislocations of same sign, there are an extended jog corresponding to a row of 1/3 interstitials in the intersected dislocation, and a trail of interstitials behind the moving dislocation. After intersection between screw and edge dislocations with different Burgers vector, there are a constriction corresponding to one 1/3 vacancy in the edge dislocation, and no point-defects behind the screw dislocation. When a moving screw dislocation intersects an edge dislocation with the same Burgers vector, the point of intersection will split into two constrictions corresponding to one 1/3 vacancy and 1/3 interstitial, respectively. The moving screw dislocation can pass the edge dislocation only after the two constrictions, which can move along the line of intersection of the two slip planes, meet and annihilate

  9. Early osteoarthritis of the patellofemoral joint.

    Science.gov (United States)

    Arendt, Elizabeth A; Berruto, Massimo; Filardo, Giuseppe; Ronga, Mario; Zaffagnini, Stefano; Farr, Jack; Ferrua, Paolo; Grassi, Alberto; Condello, Vincenzo

    2016-06-01

    Patellofemoral joint cartilage lesions are associated with a variety of clinical situations including blunt trauma, lateral patella dislocations, or as a secondary development in the setting of abnormal joint loading. There is a need for more clarity on how to best address these lesions. Most specifically, when is it necessary to surgically treat these lesions of the patella and trochlea and which technique to use? This review will focus on the spectrum of patellofemoral disease/injury and their treatment strategies, with special emphasis on cartilage damage and early osteoarthritis. Chapter sections will review the most common scenarios of cartilage damage in the patellofemoral joint, with an attempt to summarize current treatment, their outcomes, remaining challenges and unanswered questions.

  10. Elbow joint stability following experimental osteoligamentous injury and reconstruction

    DEFF Research Database (Denmark)

    Deutch, Søren R; Jensen, Steen Lund; Tyrdal, Stein

    2003-01-01

    Elbow joint dislocation was simulated in cadaveric specimens to quantify laxity induced by radial head and coronoid process lesions, either alone or in combination with collateral ligament insufficiency. The effects of lateral ligament reconstruction and radial head prosthesis replacement were also...

  11. [The hip joint in neuromuscular disorders].

    Science.gov (United States)

    Strobl, W M

    2009-07-01

    Physiologic motor and biomechanical parameters are prerequisites for normal hip development and hip function. Disorders of muscle activity and lack of weight bearing due to neuromuscular diseases may cause clinical symptoms such as an unstable hip or reduced range of motion. Disability and handicap because of pain, hip dislocation, osteoarthritis, gait disorders, or problems in seating and positioning are dependent on the severity of the disease, the time of occurrence, and the means of prevention and treatment. Preservation of pain-free and stable hip joints should be gained by balancing muscular forces and by preventing progressive dislocation. Most important is the exact indication of therapeutic options such as movement and standing therapy as well as drugs and surgery.

  12. Energetics of dislocation nucleation under a nanoindenter

    International Nuclear Information System (INIS)

    Zhang Chuanli; Xu Guanshui

    2005-01-01

    We present an analysis of dislocation nucleation under an idealized nanoindenter based on the variational boundary integral formulation of the Peierls-Nabarro dislocation model. By solving the embryonic dislocation profiles, corresponding to the relative displacements between the two adjacent atomic layers along the slip plane, we have determined the critical conditions for athermal dislocation nucleation as well as the activation energies required to thermally activate embryonic dislocations from their stable to unstable saddle point configurations. The effect of the size of the indenter on the energetics of dislocation nucleation is quantitatively characterized. The result is compared with a simplified analysis based on the application of the Rice model for dislocation nucleation at a crack tip

  13. Energetics of dislocation nucleation under a nanoindenter

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Chuanli [College of Mechanical Engineering, Yangtze University, Jingzhou, Hubei 434023 (China); Department of Mechanical Engineering, University of California, Riverside, CA 92521 (United States); Xu Guanshui [Department of Mechanical Engineering, University of California, Riverside, CA 92521 (United States)]. E-mail: guanshui.xu@ucr.edu

    2005-07-25

    We present an analysis of dislocation nucleation under an idealized nanoindenter based on the variational boundary integral formulation of the Peierls-Nabarro dislocation model. By solving the embryonic dislocation profiles, corresponding to the relative displacements between the two adjacent atomic layers along the slip plane, we have determined the critical conditions for athermal dislocation nucleation as well as the activation energies required to thermally activate embryonic dislocations from their stable to unstable saddle point configurations. The effect of the size of the indenter on the energetics of dislocation nucleation is quantitatively characterized. The result is compared with a simplified analysis based on the application of the Rice model for dislocation nucleation at a crack tip.

  14. Ipsilateral open anterior hip dislocation and open posterior elbow dislocation in an adult

    Directory of Open Access Journals (Sweden)

    Kumar Sunil

    2014-02-01

    Full Text Available 【Abstract】Open anterior dislocation of the hip is a very rare injury, especially in adults. It is a hyperabduction, external rotation and extension injury. Its combination with open posterior dislocation of the elbow has not been described in English language-based medical literature. Primary resuscitation, debridement, urgent reduction of dislocation, and adequate antibiotic support resulted in good clinical outcome in our patient. At 18 months follow-up, no signs of avascular necrosis of the femoral head or infection were observed.

  15. EXTRA-ARTICULAR FRACTURE OF THE MEDIAL END OF THE CLAVICLE ASSOCIATED WITH TYPE IV ACROMIOCLAVICULAR DISLOCATION: CAAE REPORT.

    Science.gov (United States)

    Correa, Mário Chaves; Gonçalves, Lucas Braga Jacques; Vilela, Jose Carlos Souza; Leonel, Igor Lima; Costa, Lincoln Paiva; de Andrade, Ronaldo Percopi

    2011-01-01

    Fractures of the clavicle and acromioclavicular dislocations are very common injuries when they occur separately. The combination of an acromioclavicular dislocation and a fracture of the lateral third of the clavicle is not rare. However, there are very few reported cases of acromioclavicular dislocations associated with fractures of the middle third of the clavicle; those associated with fractures of the medial third are even rarer. We report the case of an adult male who suffered an acromioclavicular dislocation (type IV) associated with a displaced extra-articular fracture of the medial end of the clavicle (Almann group 3) in a cycling accident. The patient was treated during the acute phase with open reduction and internal fixation of the two lesions. At the clinical evaluation 12 months after the surgery, the patient was asymptomatic, with full active and passive mobility, and normal strength and endurance of the shoulder girdle. Radiographs and a three-dimensional CT scan showed persistent posterosuperior subluxation of the acromioclavicular joint and anatomical consolidation of the clavicular fracture.

  16. Medial peritalar fracture dislocation of the talar body

    Directory of Open Access Journals (Sweden)

    Jacob B. Stirton

    2015-04-01

    Full Text Available Peritalar fracture dislocations typically involve the talar neck and are classified according to Hawkins. To our knowledge, peritalar fracture dislocation involving the talar body has not been formally reported. In this article, we describe a case of peritalar fracture dislocation of the talar body. Keywords: Peritalar dislocation, Talus fracture, Talar body fracture dislocation, Medial subtalar dislocation

  17. The movement of screw dislocations in tungsten

    International Nuclear Information System (INIS)

    Tian Xiaogeng; Woo Chungho

    2004-01-01

    Using Acland potential for tungsten, the movement of 1/2a screw dislocation under shear stress was investigated by molecular dynamics simulation. Equilibrated core structure was obtained by relaxation of screw dislocation with proper boundary conditions. We found that the equilibrium dislocation core has three-fold symmetry and spread out in three direction on {1 1 0} planes. The screw dislocation core could not keep the original shape when the shear stress applied. The dislocation could not move until the shear stress became large enough. The dislocation moved in zigzag when the shear stress neared the Peierls stress. When the shear stress became larger, the dislocation moved in zigzag at the beginning and than moved almost in straight line in [2-bar11] direction. The large shear stress applied, the long distance moved before the dislocation stilled in z-direction and the large velocity in y-direction

  18. Magnetic resonance imaging of hip joint cartilage and labrum

    Directory of Open Access Journals (Sweden)

    Christoph Zilkens

    2011-09-01

    Full Text Available Hip joint instability and impingement are the most common biomechanical risk factors that put the hip joint at risk to develop premature osteoarthritis. Several surgical procedures like periacetabular osteotomy for hip dysplasia or hip arthroscopy or safe surgical hip dislocation for femoroacetabular impingement aim at restoring the hip anatomy. However, the success of joint preserving surgical procedures is limited by the amount of pre-existing cartilage damage. Biochemically sensitive MRI techniques like delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC might help to monitor the effect of surgical or non-surgical procedures in the effort to halt or even reverse joint damage.

  19. The treatment of the acute acromioclavicular joint dislocation with LARS artificial ligament:a preliminary report%应用LARS人工韧带治疗急性肩锁关节脱位的初步报告

    Institute of Scientific and Technical Information of China (English)

    陈爱民; 鹿楠; 叶添文; 杨鹏; 朱磊; 李菁

    2014-01-01

    Background Currently,the clinical perspectives of surgical treatment for Tossy Ⅲacromioclavicular(AC)joint dislocations are relatively identical.Due to the post-traumatic ruptures of the acromioclavicular ligament and coracoclavicular(CC)ligament which are used to maintain stability of the joint,the clavicle moves backward and upward,and the upper arm and the scapula drops downward for the gravity of the upper arm and the influence of the sternocleidomastoid muscle.Since such complications as reduction difficulties,redislocation after external fixation,pressure ulcers of the skin,and so forth are particularly prone to occur in the conservative therapy,the operative treatment is more inclined to be adopted for the Tossy Ⅲ dislocation of the AC joint.With the single repair and fixation of the CC ligament,redislocation is likely to happen after implant removal because the ruptured ligaments healed as scar tissue.Therefore,this study uses an operative method of reconstructing and augmenting the CC ligament with LARS artificial ligament for the treatment of Tossy Ⅲ AC joint dislocation,and evaluates its clinical effect.Methods From November 2006 to July 2009,8 patients with acute AC joint dislocation of Tossy Ⅲ were admitted into our hospital.Five patients were male and 3 were female,and their ages ranged from 21 to 45.Sides:3 injuries were on the left and 5 were on the right.Seven patients suffered from falling on the ground,and 1 patient was inj ured in a traffic accident.All the patients were treated with LARS artificial ligaments to reconstruct the CC ligament.Constant score and VAS score were adopted in clinical evaluation.Zanca view of the bilateral AC joint and the axillary radiograph of the affected shoulder joint were employed for imaging evaluation.All the patients were simple Tossy Ⅲ dislocation of AC joint with no trauma of other parts and skin breakdown.Regular pre-operative examinations and evaluations were carried out after admission,and LARS

  20. Surgical Dislocation of the Hip for the Treatment of Pre-Arthritic Hip Disease.

    Science.gov (United States)

    Beaulé, Paul E; Singh, Amardeep; Poitras, Stéphane; Parker, Gillian

    2015-09-01

    The purpose of this study was to report the clinical results of surgical dislocation of the hip in the treatment of pre-arthritic hip disease. Between 2005 and 2010, eighty-two patients (89 hips) underwent a surgical dislocation of the hip at a mean age of 30.5 years (range 14.8-51.7); 10 females and 72 males. At a mean follow-up of 7.1 years (range 5-9.6) clinical function improved significantly. 6 patients were converted to total hip arthroplasty and 3 patients underwent an arthroscopy and an additional three patients had >1mm of joint space narrowing at latest follow-up giving us a 9-year cumulative Kaplan-Meier survivorship of 86.4% (CI, 79% to 94%). Thirty-four patients underwent internal fixation removal at a mean of 12.0 months (range 0.3-40.8 months). Although effective in the treatment of early hip disease, the surgical dislocation approach carries a high re-operation rate for removal of internal fixation; consequently, less invasive approaches should be considered for less complex deformities. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. A Case of Asymptomatic Occipital Condyle Fracture with Incomplete Occipitocervical Dislocation: How Did It Happen?

    Science.gov (United States)

    Anania, Pasquale; Fiaschi, Pietro; Sbaffi, Pier Filippo; Zona, Gianluigi

    2018-01-01

    Atlanto-occipital dislocation (AOD) is a lesion rarely observed in a trauma center, because of high mortality in the preclinical phase. The number of AOD survivors is increasing thanks to the improvement in prehospital resuscitation. Our goal is to describe a case of incomplete atlanto-occipital dislocation presented without any neurologic, cardiorespiratory, or metabolic problems, which remained constant even after surgical treatment. Our purpose is also to discuss treatment approaches to minimize subsequent neurologic deficits. We recommend a rapid immobilization with spine table and cervical collar, the consensual stabilization of hemodynamic and respiratory parameters, and a successive prompt occipitocervical stabilization. C2 should be included in the stabilization because of the ligamentous conformation of craniocervical joint. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Effectiveness of intra-articular lidocaine injection for reduction of anterior shoulder dislocation: randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Marcel Jun Sugawara Tamaoki

    Full Text Available CONTEXT AND OBJECTIVE: Shoulder dislocation is the most common dislocation among the large joints. The aim here was to compare the effectiveness of reduction of acute anterior shoulder dislocation with or without articular anesthesia. DESIGN AND SETTING: Prospective randomized trial conducted in Escola Paulista de Medicina, Universidade Federal de São Paulo (EPM-Unifesp. METHODS: From March 2008 to December 2009, 42 patients with shoulder dislocation were recruited. Reductions using traction-countertraction for acute anterior shoulder dislocation with and without lidocaine articular anesthesia were compared. As the primary outcome, pain was assessed through application of a visual analogue scale before reduction, and one and five minutes after the reduction maneuver was performed. Complications were also assessed. RESULTS: Forty-two patients were included: 20 in the group without analgesia (control group and 22 in the group that received intra-articular lidocaine injection. The group that received intra-articular lidocaine had a statistically greater decrease in pain over time than shown by the control group, both in the first minute (respectively: mean 2.1 (0 to 5.0, standard deviation, SD 1.3, versus mean 4.9 (2.0 to 7.0, SD 1.5; P < 0.001 and the fifth minute (respectively: mean 1.0; 0 to 3.0; SD = 1.0 versus mean 4.0; 1.0 to 6.0; SD = 1.4; P < 0.001. There was one failure in the control group. There were no other complications in either group. CONCLUSION: Reduction of anterior shoulder dislocation using intra-articular lidocaine injection is effective, since it is safe and diminishes the pain. CLINICAL TRIAL REGISTRATION: ISRCTN27127703.

  3. Fracture line index of fibular stalk and the ankle joint bone in the classification of the ankle joint trauma

    International Nuclear Information System (INIS)

    Wu Jun; Zhang Qiang

    2003-01-01

    Objective: To evaluate the fracture line index of fibular stalk and the ankle joint bone in the classification of the ankle joint trauma. Methods: Measure fracture line index of fibular stalk and the ankle joint in 217 adult cases of fracture and dislocation of ankle joint. And the cases were classified by the results of the measurement. Results: Measurement was unavailable in 9 cases of tearing fracture. In 31 cases, the lesions could not be particularly classified. And in the rest 176 cases the trauma were precisely classified. The over all successful rate was 81.6%. Conclusion: Fracture line index of fibular stalk and the ankle joint bone are valuable in classification of the trauma of the angle joint. While the specificity of this method is low in differentiating the adducting and abducting fracture of the medial angle, in which a combined investigation is recommended

  4. Stability of the elbow joint: relevant anatomy and clinical implications of in vitro biomechanical studies

    NARCIS (Netherlands)

    de Haan, J.; Schep, N. W. L.; Eygendaal, D.; Kleinrensink, G.-J.; Tuinebreijer, W. E.; den Hartog, D.

    2011-01-01

    The aim of this literature review is to describe the clinical anatomy of the elbow joint based on information from in vitro biomechanical studies. The clinical consequences of this literature review are described and recommendations are given for the treatment of elbow joint dislocation.The PubMed

  5. HRTEM studies of dislocations in cubic BN

    International Nuclear Information System (INIS)

    Nistor, L.C.; Tendeloo, G. van; Dinca, G.

    2004-01-01

    The atomic structure of dislocations in cubic boron nitride has been investigated by high resolution transmission electron microscopy. Most of the perfect dislocations, screw and 60 edge, are dissociated. A 60 dislocation which was undissociated has been analysed. Computer simulation is performed in an attempt to characterise the core structure. Twinning dislocations and dislocations resulting from the intersection of stacking faults are also revealed. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  6. HRTEM studies of dislocations in cubic BN

    Energy Technology Data Exchange (ETDEWEB)

    Nistor, L.C. [National Institute for Materials Physics, P.O. Box MG-7 Magurele, 077125 Bucharest (Romania); Tendeloo, G. van [University of Antwerp, EMAT, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Dinca, G. [Dacia Synthetic Diamond Factory, Timisoara av. 5, P.O. Box 58-52, 077350 Bucharest (Romania)

    2004-09-01

    The atomic structure of dislocations in cubic boron nitride has been investigated by high resolution transmission electron microscopy. Most of the perfect dislocations, screw and 60 edge, are dissociated. A 60 dislocation which was undissociated has been analysed. Computer simulation is performed in an attempt to characterise the core structure. Twinning dislocations and dislocations resulting from the intersection of stacking faults are also revealed. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. External fixation combined with delayed internal fixation in treatment of tibial plateau fractures with dislocation.

    Science.gov (United States)

    Tao, Xingguang; Chen, Nong; Pan, Fugen; Cheng, Biao

    2017-10-01

    The aim of this study was to evaluate the clinical efficacy of external fixation, delayed open reduction, and internal fixation in treating tibial plateau fracture with dislocation.Clinical data of 34 patients diagnosed with tibial plateau fracture complicated with dislocation between January 2009 and May 2015 were retrospectively analyzed. Fifteen patients in group A underwent early calcaneus traction combined with open reduction and internal fixation and 19 in group B received early external fixation combined with delayed open reduction and internal fixation. Operation time, postoperative complication, bone healing time, knee joint range of motion, initial weight-bearing time, Rasmussen tibial plateau score, and knee function score (HSS) were statistically compared between 2 groups.The mean follow-up time was 18.6 months (range: 5-24 months). The mean operation time in group A was 96 minutes, significantly longer than 71 minutes in group B (P  .05). In group A, initial weight-bearing time in group A was (14.0 ± 3.6) weeks, significantly differing from (12.9 ± 2.8) weeks in group B (P  0.05). Rasmussen tibial plateau score in group A was slightly lower than that in group B (P > .05). The excellent rate of knee joint function in group A was 80% and 84.21% in group B (P > .05).External fixation combined with delayed open reduction and internal fixation is a safer and more efficacious therapy of tibial plateau fracture complicated with dislocation compared with early calcaneus traction and open reduction and internal fixation.

  8. Rules for Forest Interactions between Dislocations

    International Nuclear Information System (INIS)

    Wickham, L. K.; Schwarz, K. W.; Stoelken, J. S.

    1999-01-01

    The dynamical interactions of dislocations existing on intersecting glide planes have been investigated using numerical simulations based on isotropic linear elastic theory. It is found that such dislocations either repel, attract and form growing junctions, or attract and form bound crossed states. Which of these occurs can be predicted from a surprisingly simple analysis of the initial configurations. The outcome is determined primarily by the angles which the dislocations initially make with the glide-plane intersection edge, and is largely independent of the initial distance between the dislocations, their initial curvature, or ambient applied stresses. The results provide a rule for dealing with forest interactions within the context of large multiple-dislocation computations. (c) 1999 The American Physical Society

  9. Novel utilization of 3D technology and the hybrid operating theatre: Peri-operative assessment of posterior sterno-clavicular dislocation using cone beam CT

    International Nuclear Information System (INIS)

    Crowhurst, James A; Campbell, Douglas; Whitby, Mark; Pathmanathan, Pavthrun

    2013-01-01

    A patient with a medial and posterior dislocation of the right sterno-clavicular (SC) joint and displacement of the trachea and brachiocephalic artery by the medial head of the clavicle underwent general anaesthetic in the operating theatre for an open reduction procedure. The surgeon initially attempted a closed reduction, but this required imaging to check SC alignment. The patient was transferred to an adjacent hybrid operating theatre for imaging. Cone beam computed tomography (CBCT) was performed, which successfully demonstrated a significant reduction in the dislocation of the SC joint. The trachea and brachiocephalic artery were no longer compressed or displaced. This case study demonstrates an alternative to the patient being transferred to the medical imaging department for multi-slice CT. It also describes a novel use of the hybrid operating theatre and its CBCT capabilities

  10. Novel utilization of 3D technology and the hybrid operating theatre: Peri-operative assessment of posterior sterno-clavicular dislocation using cone beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Crowhurst, James A; Campbell, Douglas; Whitby, Mark; Pathmanathan, Pavthrun [The Prince Charles Hospital, Rode Road, Chermside, Queensland (Australia)

    2013-06-15

    A patient with a medial and posterior dislocation of the right sterno-clavicular (SC) joint and displacement of the trachea and brachiocephalic artery by the medial head of the clavicle underwent general anaesthetic in the operating theatre for an open reduction procedure. The surgeon initially attempted a closed reduction, but this required imaging to check SC alignment. The patient was transferred to an adjacent hybrid operating theatre for imaging. Cone beam computed tomography (CBCT) was performed, which successfully demonstrated a significant reduction in the dislocation of the SC joint. The trachea and brachiocephalic artery were no longer compressed or displaced. This case study demonstrates an alternative to the patient being transferred to the medical imaging department for multi-slice CT. It also describes a novel use of the hybrid operating theatre and its CBCT capabilities.

  11. Effects of dislocations on electron channeling

    International Nuclear Information System (INIS)

    George, Juby; Pathak, A P

    2009-01-01

    The phenomenon of electron channeling in a crystal affected by dislocations is considered. Earlier we had considered the quantum aspects of the positron channeling in a crystal bent by dislocations where the effects of longitudinal motion of the particle were also considered along with the transverse motion. In this paper, the effective potential for the electron case is found for the two regions of dislocation-affected channel. There is considerable shift in the potential minima due to dislocations. The frequency and the corresponding spectrum of the channeling radiation due to electrons channeling through the perfect channel and the two regions of dislocation-affected channels are calculated. The spectral distribution of radiation intensity changes with the parameters of dislocation. The continuity of wavefunctions and their derivatives is used at the three boundaries and the reflection and transmission coefficients are found using these boundary conditions in the same way as in the positron case.

  12. Reduction of Anterior Shoulder Dislocation in Emergency Department; Is Entonox® Effective?

    Directory of Open Access Journals (Sweden)

    Babak Mahshidfar

    2011-12-01

    Full Text Available Introduction: An appropriate procedural sedation and analgesia (PSA is crucial to reduce a dislocated shoulder successfully in emergency department. This study compares sedative effect of inhalational Entonox® (En to intra-venous (IV Midazolam plus Fentanyl (F+M. Methods: 120 patients with recurrent anterior shoulder dislocation were randomly assigned into two groups. 60 patients (group F+M received 0.1 mg/kg IV Midazolam plus 3µg/kg IV Fentanyl and 60 patients (group En received Entonox® with self administration face mask on an on-demand basis. Traction/counter-traction method was used to reduce the dislocated shoulder joint in both groups. Results: 48 out of 60 (80% patients in group F+M and 6 out of 60 (10% patients in group En had successful reduction (p < 0.0001. The mean pain score reduction was 6.3 ± 1.2 for group F+M and 3 ± 0.9 for group En (p < 0.0001. There was a statistically significant difference in mean patient satisfaction (assessed with Likert score between two groups (4.45 ± 0.6 for group F+M and 2.3 ± 1 for group En; p < 0.0001. Duration of entire procedure (since the beginning of PSA up to the end of successful or unsuccessful reduction was shorter in Group F+M, but successful reductions occurred earlier in group En. No major side effect such as airway compromise, retracted respiratory depression, or circulatory failure was occurred in any group. Conclusion: Entonox® may not be an appropriate agent to help reducing a dislocated shoulder.

  13. Estudo comparativo da eminectomia e do uso de miniplaca na eminência articular para tratamento da luxação recidivante da articulação temporomandibular Comparative study of eminectomy and use of bone miniplate in the articular eminence for the treatment of recurrent temporomandibular joint dislocation

    Directory of Open Access Journals (Sweden)

    Álvaro B. Cardoso

    2005-02-01

    Full Text Available AA luxação da articulação temporomandibular ocorre quando o côndilo mandibular move-se para fora da cavidade glenóide e permanece travado anteriormente à eminência articular, sendo sua ocorrência repetitiva (luxação recidivante geralmente associada a hipermobilidade mandibular e a inclinação da eminência articular. OBJETIVO: Neste estudo avaliou-se, clínica e radiograficamente, a técnica de eminectomia e do uso de miniplaca na eminência articular para tratamento da luxação recidivante da articulação temporomandibular de pacientes operados no Hospital Universitário Osvaldo Cruz (HUOC/UPE, no período de janeiro de 2001 a setembro de 2003. FORMA DE ESTUDO: Retrospectivo. MATERIAL E MÉTODO: A amostra foi composta por 11 pacientes. A cirurgia de eminectomia foi realizada em nove articulações de cinco pacientes, enquanto a cirurgia para colocação de miniplaca na eminência articular em 11 articulações de seis pacientes. A obtenção dos dados foi efetuada através da análise de prontuários e de nova consulta pós-operatória. RESULTADOS: Os resultados mostraram não haver maiores complicações pós-operatórias para as duas técnicas. A abertura bucal máxima foi maior nos pacientes operados pela técnica de eminectomia e nenhum dos pacientes apresentou recorrência da luxação. CONCLUSÃO: Concluiu-se que as duas técnicas mostraram-se eficientes para o tratamento da luxação recidivante da articulação temporomandibular.Dislocation of the temporomandibular joint occurs when the mandibular condyle exits the glenoidal cavity and remains anteriorly locked to the articular eminence. It is repetitive (recurrent dislocation, usually associated with mandibular hypermobility and inclination of the articular eminence. AIM: This study intended to clinically and radiologically assess the technique of eminectomy and the use of a miniplate on the articular eminence for the treatment of recurrent dislocation of the

  14. Energy flow around a moving dislocation

    International Nuclear Information System (INIS)

    Koizumi, H; Kirchner, H O K

    2009-01-01

    A dislocation moving in a lattice emits lattice waves. We study the energy flow accompanying the lattice wave emission in a molecular dynamics situation. About two thirds of the static free energy are emitted as lattice waves from the moving dislocation. Work done by the region around the dislocation helps to initiate the motion from the unstable equilibrium state under a small applied stress, or to compensate the energy emitted as lattice waves when the dislocation makes a long distance motion under a larger stress.

  15. [The Postero-Lateral Approach--An Alternative to Closed Anterior-Posterior Screw Fixation of a Dislocated Postero-Lateral Fragment of the Distal Tibia in Complex Ankle Fractures].

    Science.gov (United States)

    von Rüden, C; Hackl, S; Woltmann, A; Friederichs, J; Bühren, V; Hierholzer, C

    2015-06-01

    The dislocated posterolateral fragment of the distal tibia is considered as a key fragment for the successful reduction of comminuted ankle fractures. The reduction of this fragment can either be achieved indirectly by joint reduction using the technique of closed anterior-posterior screw fixation, or directly using the open posterolateral approach followed by plate fixation. The aim of this study was to compare the outcome after stabilization of the dislocated posterolateral tibia fragment using either closed reduction and screw fixation, or open reduction and plate fixation via the posterolateral approach in complex ankle fractures. In a prospective study between 01/2010 and 12/2012, all mono-injured patients with closed ankle fractures and dislocated posterolateral tibia fragments were assessed 12 months after osteosynthesis. Parameters included: size of the posterolateral tibia fragment relative to the tibial joint surface (CT scan, in %) as an indicator of injury severity, unreduced area of tibial joint surface postoperatively, treatment outcome assessed by using the "Ankle Fracture Scoring System" (AFSS), as well as epidemiological data and duration of the initial hospital treatment. In 11 patients (10 female, 1 male; age 51.6 ± 2.6 years [mean ± SEM], size of tibia fragment 42.1 ± 2.5 %) the fragment fixation was performed using a posterolateral approach. Impaired postoperative wound healing occurred in 2 patients of this group. In the comparison group, 12 patients were treated using the technique of closed anterior-posterior screw fixation (10 female, 2 male; age 59.5 ± 6.7 years, size of tibia fragment 45.9 ± 1.5 %). One patient of this group suffered an incomplete lesion of the superficial peroneal nerve. Radiological evaluation of the joint surface using CT scan imaging demonstrated significantly less dislocation of the tibial joint surface following the open posterolateral approach (0.60 ± 0.20 mm) compared to the closed

  16. Atomistic simulations of dislocation processes in copper

    DEFF Research Database (Denmark)

    Vegge, T.; Jacobsen, K.W.

    2002-01-01

    We discuss atomistic simulations of dislocation processes in copper based on effective medium theory interatomic potentials. Results on screw dislocation structures and processes are reviewed with particular focus on point defect mobilities and processes involving cross slip. For example......, the stability of screw dislocation dipoles is discussed. We show that the presence of jogs will strongly influence cross slip barriers and dipole stability. We furthermore present some new results on jogged edge dislocations and edge dislocation dipoles. The jogs are found to be extended, and simulations...

  17. Facet joint syndrome

    International Nuclear Information System (INIS)

    Zigrai, M.; Zakovic, J.; Brezinova, M.; Pavlovicova, M.

    2002-01-01

    It is the purpose of the study to demonstrate the clinical relevance of degenerative changes in the facet joint of patients with low back pain irradiating to the lower extremities, and discuss some problems relating to diagnosis and different diagnosis. 119 patients presenting the listed bellow syndromes are covered by the study: scoliosis, polytopic pain vertebral syndrome, paresis and history of trauma. all patients undergo comprehensive neurological examination with special attention focused on the spine: CT and plain x-rays are taken of the lumbosacral segment to assess the condition of the facet joints. The neurological examination demonstrates in all cases pain syndrome in the lumbar spine referred to one or both lower extremities. In 56% it is a matter of persisting pain, and in 44% - recurrent. More than half of the patients complain of sacroiliac (SI) dislocation and palpatory pain. Unilateral or bilateral degenerative changes are documented by imaging studies in all patients, including: subchondral thickening, osteopathy narrowing the lateral or central part of the spinal canal with ensuing nerve root compression. The lumbosacral zygoapophyseal joints are source of pseudoradicular pain. A correlation between clinical picture and GT changes is noted in all patients with facet joint syndrome. CT is an indispensable method in diagnosing facet joint syndrome. (authors)

  18. Brachial artery injury due to closed posterior elbow dislocation: case report☆

    Directory of Open Access Journals (Sweden)

    Alberto Naoki Miyazaki

    2016-04-01

    Full Text Available An association between closed posterior elbow dislocation and traumatic brachial artery injury is rare. Absence of radial pulse on palpation is an important warning sign and arteriography is the gold-standard diagnostic test. Early diagnosis is essential for appropriate treatment to be provided. This consists of joint reduction and immobilization, along with urgent surgical restoration of arterial flow. Here, a case (novel to the Brazilian literature of an association between these injuries (and the treatment implemented in a 27-year-old male patient is reported. These injuries were sustained through physical assault.

  19. Neglected locked vertical patellar dislocation

    Science.gov (United States)

    Gupta, Rakesh Kumar; Gupta, Vinay; Sangwan, Sukhbir Singh; Kamboj, Pradeep

    2012-01-01

    Patellar dislocations occurring about the vertical and horizontal axis are rare and irreducible. The neglected patellar dislocation is still rarer. We describe the clinical presentation and management of a case of neglected vertical patellar dislocation in a 6 year-old boy who sustained an external rotational strain with a laterally directed force to his knee. Initially the diagnosis was missed and 2 months later open reduction was done. The increased tension generated by the rotation of the lateral extensor retinaculum kept the patella locked in the lateral gutter even with the knee in full extension. Traumatic patellar dislocation with rotation around a vertical axis has been described earlier, but no such neglected case has been reported to the best of our knowledge. PMID:23162154

  20. Neglected locked vertical patellar dislocation

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Gupta

    2012-01-01

    Full Text Available Patellar dislocations occurring about the vertical and horizontal axis are rare and irreducible. The neglected patellar dislocation is still rarer. We describe the clinical presentation and management of a case of neglected vertical patellar dislocation in a 6 year-old boy who sustained an external rotational strain with a laterally directed force to his knee. Initially the diagnosis was missed and 2 months later open reduction was done. The increased tension generated by the rotation of the lateral extensor retinaculum kept the patella locked in the lateral gutter even with the knee in full extension. Traumatic patellar dislocation with rotation around a vertical axis has been described earlier, but no such neglected case has been reported to the best of our knowledge.

  1. Popliteal artery injury following traumatic knee joint dislocation in a 14-year-old boy: A case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Cvetković Slobodan

    2014-01-01

    Full Text Available Introduction. Posterior knee joint dislocation associated with injury of the popliteal artery in children is an extremely rare condition. Rapid diagnosis and treatment are essential for limb salvage and function. Case report. We reported a 14-year-old boy who suffered traumatic displacement of the right knee and contusion of the popliteal artery during motorcycle accident. The diagnosis was confirmed using Doppler and duplex ultrasonography and digital substraction transfemoral arteriography. The urgent surgical procedure was performed using posterior approach to the popliteal artery. During the surgical exploration, rupture of the posterior cruciate ligament associated with thrombosed popliteal artery have been found. The damaged popliteal artery was resected and replaced with autologous saphenous vein graft. The last stage of the procedure was a transosseous femoral fixation of posterior circuate ligament. A 3-year-follow-up after the surgery demonstrated intact arterial perfusion and very good function of the knee with a minimal difference as compared with the contralateral knee. Conclusion. Combined orthopedic and vascular injuries are very rare in children. They require combined treatment. [Projekat Ministarstva nauke Republike Srbije, br. 175008

  2. Medial patellar ossification after patellar instability: a radiographic finding indicative of prior patella subluxation/dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Jerabek, Seth A. [Harvard Combined Orthopaedic Surgery Residency Program, Boston, MA (United States); Asnis, Peter D.; Poon, Steven K.; Gill, Thomas J. [Massachusetts General Hospital, Department of Orthopaedic Surgery, Boston, MA (United States); Bredella, Miriam A.; Ouellette, Hugue A. [Massachusetts General Hospital, Department of Radiology, Boston, MA (United States)

    2009-08-15

    To describe the correlation between medial patellar ossification and prior patella subluxation and/or dislocation. A retrospective billing database search identified 544 patients who had been diagnosed with patellar instability over a 13-year period. One hundred twenty-eight patients met the inclusion criteria. After review by a staff orthopedic surgeon and two musculoskeletal radiologists, 28 patients were found to have medial patellar ossification. The size and location of medial patellar ossification was recorded. Of the 28 patients (20 males, eight females, age 13-66 years, mean 28 years) who were found to have medial patellar ossification, 22 had radiographs, 16 had magnetic resonance imaging, and ten had both. The medial patellar ossification ranged in size from 2 to 18 mm with an average of 6.8 mm. Twelve were located in the medial patellofemoral ligament (MPFL), 14 in the medial joint capsule, and two in both the MPFL and joint capsule. Twenty-seven of 28 patients had a single ossification, and one patient had two ossifications. The timing from injury to first imaging of the lesion ranged from 10 days to a chronic history ({>=}35 years) of patellar instability. Medial patellar ossification correlates with a history of prior patella subluxation and/or dislocation. The medial ossification can be seen within the MPFL or the medial joint capsule, suggesting remote injury to these structures. The presence of this lesion will prompt physicians to evaluate for patellar instability. (orig.)

  3. Medial patellar ossification after patellar instability: a radiographic finding indicative of prior patella subluxation/dislocation

    International Nuclear Information System (INIS)

    Jerabek, Seth A.; Asnis, Peter D.; Poon, Steven K.; Gill, Thomas J.; Bredella, Miriam A.; Ouellette, Hugue A.

    2009-01-01

    To describe the correlation between medial patellar ossification and prior patella subluxation and/or dislocation. A retrospective billing database search identified 544 patients who had been diagnosed with patellar instability over a 13-year period. One hundred twenty-eight patients met the inclusion criteria. After review by a staff orthopedic surgeon and two musculoskeletal radiologists, 28 patients were found to have medial patellar ossification. The size and location of medial patellar ossification was recorded. Of the 28 patients (20 males, eight females, age 13-66 years, mean 28 years) who were found to have medial patellar ossification, 22 had radiographs, 16 had magnetic resonance imaging, and ten had both. The medial patellar ossification ranged in size from 2 to 18 mm with an average of 6.8 mm. Twelve were located in the medial patellofemoral ligament (MPFL), 14 in the medial joint capsule, and two in both the MPFL and joint capsule. Twenty-seven of 28 patients had a single ossification, and one patient had two ossifications. The timing from injury to first imaging of the lesion ranged from 10 days to a chronic history (≥35 years) of patellar instability. Medial patellar ossification correlates with a history of prior patella subluxation and/or dislocation. The medial ossification can be seen within the MPFL or the medial joint capsule, suggesting remote injury to these structures. The presence of this lesion will prompt physicians to evaluate for patellar instability. (orig.)

  4. Acromioclavicular joint reconstruction using the LockDown synthetic implant: a study with cadavers.

    Science.gov (United States)

    Taranu, R; Rushton, P R P; Serrano-Pedraza, I; Holder, L; Wallace, W A; Candal-Couto, J J

    2015-12-01

    Dislocation of the acromioclavicular joint is a relatively common injury and a number of surgical interventions have been described for its treatment. Recently, a synthetic ligament device has become available and been successfully used, however, like other non-native solutions, a compromise must be reached when choosing non-anatomical locations for their placement. This cadaveric study aimed to assess the effect of different clavicular anchorage points for the Lockdown device on the reduction of acromioclavicular joint dislocations, and suggest an optimal location. We also assessed whether further stability is provided using a coracoacromial ligament transfer (a modified Neviaser technique). The acromioclavicular joint was exposed on seven fresh-frozen cadaveric shoulders. The joint was reconstructed using the Lockdown implant using four different clavicular anchorage points and reduction was measured. The coracoacromial ligament was then transferred to the lateral end of the clavicle, and the joint re-assessed. If the Lockdown ligament was secured at the level of the conoid tubercle, the acromioclavicular joint could be reduced anatomically in all cases. If placed medial or 2 cm lateral, the joint was irreducible. If the Lockdown was placed 1 cm lateral to the conoid tubercle, the joint could be reduced with difficulty in four cases. Correct placement of the Lockdown device is crucial to allow anatomical joint reduction. Even when the Lockdown was placed over the conoid tubercle, anterior clavicle displacement remained but this could be controlled using a coracoacromial ligament transfer. ©2015 The British Editorial Society of Bone & Joint Surgery.

  5. Contribution to the study of screw dislocations; Contribution a l'etude des dislocations helicoidales

    Energy Technology Data Exchange (ETDEWEB)

    Grilhe, J [Commissariat a l' Energie Atomique, Fontenay aux Roses (France). Centre d' Etudes Nucleaires

    1965-03-01

    The aim of this work is to study the germination, growth and properties of screw dislocations. In the introduction (first chapter), we describe briefly the main experimental results obtained by various authors (observations of screws by Amelinckx and Bontinck in ionic crystals, by Dash in silicon crystals and by Thomas and Whelan in aluminium based alloys). We then make a few considerations concerning characteristic geometry of screws and the various methods used for calculating the energy of a dislocation. In the second chapter we study the problems involving only slip of the screw around its cylinder. We calculate the equilibrium step as a function of the forces acting on the extremities. We determine the critical stress required to disrupt the screw and study the interactions between the screw and other dislocations of the lattice. In the third chapter we consider the problem of the stability when the dislocation can climb by absorption or emission of vacancies. We study separately the stability of the size which only involves volume diffusion and the stability of the shape which depends only on the rearrangement of the vacancies along the dislocation. In chapter four we put forward a germination model for the screws: since the vacancies are not absorbed by the screw dislocations, they form clusters which take up a spiral form. The formation of these spirals is studied from the geometrical point of view in face-centered cubic systems. In chapter five we make use of the results obtained in chapters two and three for studying the growth of the spirals. (author) [French] Le but de ce travail est d'etudier la germination, la croissance et les proprietes des dislocations helico ales. Dans l'introduction (premier chapitre), nous exposons brievement les principaux resultats experimentaux obtenus par differents auteurs (observations d'helice par Amelinckx et Bontinck dans les cristaux ioniques, par Dash dans des cristaux de silicium et par Thomas et Whelan dans des

  6. Features rehabilitation of infants with congenital hip dislocation on the stages of conservative treatment

    Directory of Open Access Journals (Sweden)

    Sergei Yurievich Voloshin

    2015-06-01

    Full Text Available Congenital dislocation of the hip is one of the most common diseases in children leading to disability, which is difficult to diagnose in the first days of life. In the structure of congenital orthopedic diseases congenital dislocation of the hip holds one of the first places. This determines the importance and urgency of the problem, as the most complete restoration of anatomical structures and functions of the hip joint in children occurs in the early diagnosis and comprehensive, timely begun treatment. Rehabilitation of children in the first year of life should be early, systematic, comprehensive and differentiated. Technique of rehabilitation stages conservative treatment includes: wearing functional tires, gymnastics, massage, physiotherapy, therapeutic swimming. This prevents the progression of the disease, the development of early and late complications, does not violate the static-dynamic functions without delay verticalization.

  7. Atomistic simulation of hydrogen dynamics near dislocations in vanadium hydrides

    International Nuclear Information System (INIS)

    Ogawa, Hiroshi

    2015-01-01

    Highlights: • Hydrogen–dislocation interaction was simulated by molecular dynamics method. • Different distribution of H atoms were observed at edge and screw dislocation. • Planner distribution of hydrogen may be caused by partialized edge dislocation. • Hydrogen diffusivity was reduced in both edge and screw dislocation models. • Pipe diffusion was observed for edge dislocation but not for screw dislocation. - Abstract: Kinetics of interstitial hydrogen atoms near dislocation cores were analyzed by atomistic simulation. Classical molecular dynamics method was applied to model structures of edge and screw dislocations in α-phase vanadium hydride. Simulation showed that hydrogen atoms aggregate near dislocation cores. The spatial distribution of hydrogen has a planner shape at edge dislocation due to dislocation partialization, and a cylindrical shape at screw dislocation. Simulated self-diffusion coefficients of hydrogen atoms in dislocation models were a half- to one-order lower than that of dislocation-free model. Arrhenius plot of self-diffusivity showed slightly different activation energies for edge and screw dislocations. Directional dependency of hydrogen diffusion near dislocation showed high and low diffusivity along edge and screw dislocation lines, respectively, hence so called ‘pipe diffusion’ possibly occur at edge dislocation but does not at screw dislocation

  8. Dislocation evolution and properties enhancement of GH2036 by laser shock processing: Dislocation dynamics simulation and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ren, X.D., E-mail: renxd@mail.ujs.edu.cn [School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013 (China); Zhou, W.F.; Ren, Y.P.; Xu, S.D.; Liu, F.F. [School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013 (China); Yuan, S.Q. [Research Center of Fluid Machinery Engineering and Technical, Jiangsu University, Zhenjiang 212013 (China); Ren, N.F.; Huang, J.J. [School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013 (China)

    2016-01-27

    This paper systematically investigated the effect of laser shock processing (LSP) on dislocation evolution and microstructure configuration of GH2036 alloy. Surface topography and roughness were tested by Axio CSM 700 microscope. The dislocation configurations were characterized by transmission electron microscope (TEM) and simulated by multi-scale discrete dislocation dynamics (DD) method. The results have confirmed that LSP had a beneficial effect on micro-hardness, which could be increased by 16%, and the surface topography exhibited excellent stability even after thermal cycle. The dislocation density and stress–strain response have strong dependence on laser power intensity. Reasonable agreement between DD simulation and experiments is achieved. The results showed that complex random microstructures can be observed in the shocked surface. The grain refinement mechanism of LSP GH2036 involves dislocation segmentation and twin intersections.

  9. The effect of length scale on the determination of geometrically necessary dislocations via EBSD continuum dislocation microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ruggles, T.J., E-mail: timmyruggs@gmail.com [National Institute of Aerospace, 100 Exploration Way, Hampton, VA 23666 (United States); Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602 (United States); Rampton, T.M. [EDAX Inc., 91 McKee Drive, Mahwah, NJ 07430 (United States); Khosravani, A. [Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Fullwood, D.T. [Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602 (United States)

    2016-05-15

    Electron backscatter diffraction (EBSD) dislocation microscopy is an important, emerging field in metals characterization. Currently, calculation of geometrically necessary dislocation (GND) density is problematic because it has been shown to depend on the step size of the EBSD scan used to investigate the sample. This paper models the change in calculated GND density as a function of step size statistically. The model provides selection criteria for EBSD step size as well as an estimate of the total dislocation content. Evaluation of a heterogeneously deformed tantalum specimen is used to asses the method. - Highlights: • The GND to SSD transition with increasing step size is analytically modeled. • Dislocation density of a microindented tantalum single crystal is measured. • Guidelines for step size selection in EBSD dislocation microscopy are presented.

  10. Riemann–Cartan Geometry of Nonlinear Dislocation Mechanics

    KAUST Repository

    Yavari, Arash

    2012-03-09

    We present a geometric theory of nonlinear solids with distributed dislocations. In this theory the material manifold-where the body is stress free-is a Weitzenböck manifold, that is, a manifold with a flat affine connection with torsion but vanishing non-metricity. Torsion of the material manifold is identified with the dislocation density tensor of nonlinear dislocation mechanics. Using Cartan\\'s moving frames we construct the material manifold for several examples of bodies with distributed dislocations. We also present non-trivial examples of zero-stress dislocation distributions. More importantly, in this geometric framework we are able to calculate the residual stress fields, assuming that the nonlinear elastic body is incompressible. We derive the governing equations of nonlinear dislocation mechanics covariantly using balance of energy and its covariance. © 2012 Springer-Verlag.

  11. Internal stresses, dislocation mobility and ductility

    Science.gov (United States)

    Saada, G.

    1991-06-01

    The description of plastic deformation must take into account individual mechanisms and heterogeneity of plastic strain. Influence of dislocation interaction with forest dislocations and of cross slip are connected with the organization of dipole walls. The latter are described and their development is explained as a consequence of edge effects. Applications are discussed. La description de la déformation plastique doit prendre en compte les interactions individuelles des dislocations et l'hétérogénéité à grande échelle de la déformation plastique. Les interactions des dislocations mobiles avec la forêt de dislocations, le glissement dévié, ont pour effet la création de parois dipolaires. Celles-ci sont décrites et leur développement est appliqué à partir des effets de bord.

  12. Distal Clavicle Osteolysis after Modified Weaver-Dunn’s Procedure for Chronic Acromioclavicular Dislocation: A Case Report and Review of Complications

    Directory of Open Access Journals (Sweden)

    Eduard Alentorn-Geli

    2014-01-01

    Full Text Available Distal clavicle osteolysis after acromioclavicular joint stabilization has only been described after the use of hardware for clavicle stabilization or synthetic graft causing a foreign body reaction. This paper reports a very rare case of distal clavicle osteolysis after modified Weaver-Dunn procedure for the treatment of chronic acromioclavicular joint dislocation. The paper also provides a comprehensive review of complications of this surgical technique and discusses a potential vascular etiology and preventive strategies aimed at avoiding clavicle osteolysis.

  13. Statistics of dislocation pinning at localized obstacles

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, A. [S. N. Bose National Centre for Basic Sciences, Salt Lake, Kolkata 700098 (India); Bhattacharya, M., E-mail: mishreyee@vecc.gov.in; Barat, P. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064 (India)

    2014-10-14

    Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning of dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.

  14. Ultrasonic Study of Dislocation Dynamics in Lithium -

    Science.gov (United States)

    Han, Myeong-Deok

    1987-09-01

    Experimental studies of dislocation dynamics in LiF single crystals, using ultrasonic techniques combined with dynamic loading, were performed to investigate the time evolution of the plastic deformation process under a short stress pulse at room temperature, and the temperature dependence of the dislocation damping mechanism in the temperature range 25 - 300(DEGREES)K. From the former, the time dependence of the ultrasonic attenuation was understood as resulting from dislocation multiplication followed by the evolution of mobile dislocations to immobile ones under large stress. From the latter, the temperature dependence of the ultrasonic attenuation was interpreted as due to the motion of the dislocation loops overcoming the periodic Peierls potential barrier in a manner analogous to the motion of a thermalized sine-Gordon chain under a small stress. The Peierls stress obtained from the experimental results by application of Seeger's relaxation model with exponential dislocation length distribution was 4.26MPa, which is consistent with the lowest stress for the linear relation between the dislocation velocity and stress observed by Flinn and Tinder.

  15. An experimental study of dislocation loop nucleation

    International Nuclear Information System (INIS)

    Bounaud, J.Y.; Leteurtre, J.

    1975-01-01

    The nucleation of dislocation loops is experimentally studied by observing the demixion of the Burgers vectors of dislocation loops nucleated in copper whiskers irradiated in flexion by fission fragments at room temperature. The demixion of Burgers vectors is observed by the dimensional effects of dislocation loops: after irradiation, the applied stress is removed; the whisker shows a residual strain that is due to loops because, after an annealing treatment to evaporate dislocation loops, each whisker recovers its initial straight shape. Everywhere along the whisker, the radius of curvature is measured and plotted vs the max. applied stress. Estimations of the interstitial and vacancy dislocation loop nuclei are derived [fr

  16. Representation of dislocation cores using Nye tensor distributions

    International Nuclear Information System (INIS)

    Hartley, Craig S.; Mishin, Y.

    2005-01-01

    This paper demonstrates how the cores of atomistically simulated dislocations in Cu and Al can be represented by a distribution of infinitesimal dislocations described by appropriate components of the Nye tensor. Components calculated from atomic positions in the dislocated crystal are displayed as contour plots on the plane normal to the dislocation line. The method provides an accurate and instructive means for characterizing dislocation core structures and calculating the total Burgers vector

  17. Zygomatic arch-atlas wing stabilization in 5 dogs with atlanto-occipital dislocation.

    Science.gov (United States)

    Dolera, Mario; Malfassi, Luca; Bianchi, Cristina; Carrara, Nancy; Corbetta, Laura; Finesso, Sara; Marcarini, Silvia; Mazza, Giovanni; Pavesi, Simone; Sala, Massimo

    2016-07-01

    The aim of this work was to present a novel minimally invasive surgical stabilization technique for canine atlanto-occipital dislocation and to report the associated magnetic resonance imaging (MRI) findings. All 5 dogs in this case series underwent 1.5 T MRI of the head and neck and 3 underwent both MRI and computed tomography (CT). Atlanto-occipital dislocations were diagnosed based on the increased joint space between the occipital condyles and the atlas on MRI. Surgery was performed immediately with a never previously described fixation technique based on an external ligature. The stabilization was performed via 4 holes drilled in the zygomatic processes and in the atlas wings on each side. A nylon monofilament of 1 mm diameter was inserted in the 4 holes, and an O-shaped ligature was carried out externally to the skin through the ipsilateral zygomatic arch. Ligatures were removed within 2 months. At the postsurgical follow-up examination, 14 days after surgery, all dogs were found to be ambulatory. Atlanto-occipital stability was assessed by clinical examination with an average of 24 months of follow-up. The positive outcomes in this case series suggest that atlanto-occipital dislocation may be surgically treated with this novel technique, irrespective of the severity of the clinical presentation and associated lesions observed on MRI.

  18. Structure of the Dislocation in Sapphire

    DEFF Research Database (Denmark)

    Bilde-Sørensen, Jørgen; Thölen, A. R.; Gooch, D. J.

    1976-01-01

    Experimental evidence of the existence of 01 0 dislocations in the {2 0} prism planes in sapphire has been obtained by transmission electron microscopy. By the weak-beam technique it has been shown that the 01 0 dislocations may dissociate into three partials. The partials all have a Burgers vector...... of ⅓ 01 0 and are separated by two identical faults. The distance between two partials is in the range 75-135 Å, corresponding to a fault energy of 320±60 mJ/m2. Perfect 01 0 dislocations have also been observed. These dislocations exhibited either one or two peaks when imaged in the (03 0) reflection...

  19. Dislocation of jaws

    International Nuclear Information System (INIS)

    Katzberg, R.W.; Hayakawa, K.; Anderson, Q.N.; Manzione, J.V.; Helms, C.A.; Tallents, R.

    1984-01-01

    Pluri-directional tomographic and arthrotomographic findings are described in six patients with dislocation of the jaw severe enough to require medical assistance. A grooved defect along the posterior aspect of the condylar head was noted in two of the six patients. The arthrotomographic findings that were obtained in one patient that was dislocated at the time of the arthrogram did not suggest a meniscocondyle incoordination as a mechanism. However, arthrotomographic findings in the six reported cases suggest that significant intra-articular soft tissue damage may result. (orig.)

  20. Partial trapeziectomy and interposition of fascia lata allograft in the operative treatment of thumb base osteoarthritis

    NARCIS (Netherlands)

    Spaans, Anne J.; Weijns, Marieke E.; Braakenburg, Assa; Van Minnen, Leo Paul; Mink Van Der Molen, Aebele B.

    2016-01-01

    Aim: The purpose of this retrospective cohort study was to evaluate the results of fascia lata allograft interposition after partial trapeziectomy in patients with symptomatic first carpometacarpal joint osteoarthritis. Methods and results: Twenty-one patients (22 thumbs) with Eaton-Glickel stage II

  1. Dorsal bridge plating or transarticular screws for Lisfranc fracture dislocations.

    Science.gov (United States)

    Kirzner, N; Zotov, P; Goldbloom, D; Curry, H; Bedi, H

    2018-04-01

    Aims The aim of this retrospective study was to compare the functional and radiological outcomes of bridge plating, screw fixation, and a combination of both methods for the treatment of Lisfranc fracture dislocations. Patients and Methods A total of 108 patients were treated for a Lisfranc fracture dislocation over a period of nine years. Of these, 38 underwent transarticular screw fixation, 45 dorsal bridge plating, and 25 a combination technique. Injuries were assessed preoperatively according to the Myerson classification system. The outcome measures included the American Orthopaedic Foot and Ankle Society (AOFAS) score, the validated Manchester Oxford Foot Questionnaire (MOXFQ) functional tool, and the radiological Wilppula classification of anatomical reduction. Results Significantly better functional outcomes were seen in the bridge plate group. These patients had a mean AOFAS score of 82.5 points, compared with 71.0 for the screw group and 63.3 for the combination group (p bridge plate group, 38.1 in the screw group, and 45.5 in the combination group (p bridge plating have better functional and radiological outcomes than those treated with transarticular screws or a combination technique. Cite this article: Bone Joint J 2018;100-B:468-74.

  2. Computed tomography of the patellofemoral alignment after arthroscopic reconstruction following patella dislocation; Postoperative Bestimmung des patellofemoralen Alignements nach Patellaluxation - eine computertomographische Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, R.J.; Hidajat, N.; Maeurer, J.; Felix, R. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-Univ. Berlin (Germany); Weiler, A.; Hoeher, J. [Sektion Sporttraumatologie und Arthroskopie, Klinik fuer Unfall- und Wiederherstellungschirurgie, Charite, Campus Virchow-Klinikum, Humboldt-Univ. Berlin (Germany)

    2003-04-01

    Purpose: To evaluate the diagnostic impact of different CT-based measurements to analyze the patellofemoral alignment after arthroscopic reconstruction in patients with patella dislocation. Materials and Methods: In 18 patients with dislocation of the patella, CT of the patellofemoral joint was performed after arthroscopic reconstruction. Various methods recommended in the literature were used to analyze the structure and the alignment of the patellofemoral joint with a relaxed quadriceps muscle. Axial CT scans were taken in four different knee flexion angles (15 , 30 , 45 , 60 ). Results: After arthroscopic stabilization in patients with patella dislocation, only the lateral patellofemoral angle (15 and 30 knee flexion) and the congruence angle (15 knee flexion) showed significant differences between the CT-measurements in the normal and the operated group. The differences of the remaining mean values were not significant due to a high standard deviation. With increasing flexion of the knee, the differences between the normal and the dislocation group almost disappeared. Only the lateral patellofemoral angle, the patella tilt and the lateral patella shift revealed differences between the normal and the group with recurrent dislocation in every degree of knee flexion. With increasing knee flexion above 30 and especially at 60 , the majority of the measured values returned to the normal range. Conclusions: For CT-measurements of the patellofemoral joint after arthroscopic stabilization, the patellofemoral angle and the congruence angle seemed to be most useful. The measurements of the patellofemoral joint should be taken in various degrees of knee flexion. (orig.) [German] Ziel: Evaluation der Aussagekraft verschiedener CT-Vermessungsmethoden des Patellofemoralgelenkes nach arthroskopischer Stabilisierung bei Patellaluxation. Material und Methode: Axiale CT-Vermessung des Patellofemoralgelenkes bei 18 Patienten nach arthroskopischer medialer patellofemoraler Naht

  3. Smectic meniscus and dislocations

    International Nuclear Information System (INIS)

    Geminard, J.C.; Oswald, P.; Holyst, R.

    1998-01-01

    In ordinary liquids the size of a meniscus and its shape is set by a competition between surface tension and gravity. The thermodynamical process of its creation can be reversible. On the contrary, in smectic liquid crystals the formation of the meniscus is always an irreversible thermodynamic process since it involves the creation of dislocations (therefore it involves friction). Also the meniscus is usually small in experiments with smectics in comparison to the capillary length and therefore the gravity does not play any role in determining the meniscus shape. Here we discuss the relation between dislocations and meniscus in smectics. The theoretical predictions are supported by a recent experiment performed on freely suspended films of smectic liquid crystals. In this experiment the measurement of the meniscus radius of curvature gives the pressure difference, Δp, according to the Laplace law. From the measurements of the growth dynamics of a dislocation loop (governed by Δp) we find the line tension (∼8 x 10 -8 dyn) and the mobility of an elementary edge dislocation (∼4 x 10 - 7 cm 2 s/g). (author)

  4. Dynamic aspects of dislocation motion: atomistic simulations

    International Nuclear Information System (INIS)

    Bitzek, Erik; Gumbsch, Peter

    2005-01-01

    Atomistic simulations of accelerating edge and screw dislocations were carried out to study the dynamics of dislocations in a face centered cubic metal. Using two different embedded atom potentials for nickel and a simple slab geometry, the Peierls stress, the effective mass, the line tension and the drag coefficient were determined. A dislocation intersecting an array of voids is used to study dynamic effects in dislocation-obstacle interactions. A pronounced effect caused by inertial overshooting is found. A dynamic line tension model is developed which reproduces the simulation results. The model can be used to easily estimate the magnitude of inertial effects in the interaction of dislocations with localized obstacles for different obstacle strengths, -spacings and temperatures

  5. Nature of Dislocations in Silicon

    DEFF Research Database (Denmark)

    Hansen, Lars Bruno; Stokbro, Kurt; Lundqvist, Bengt

    1995-01-01

    Interaction between two partial 90 degrees edge dislocations is studied with atomic-scale simulations using the effective-medium tight-binding method. A large separation between the two dislocations (up to 30 Angstrom), comparable to experimental values, is achieved with a solution of the tight-b...

  6. Osteoporosis-Related Simultaneous Four Joints Fractures and Dislocation after a Seizure: A Case Report

    Directory of Open Access Journals (Sweden)

    Abdullah S. AlOmran

    2010-01-01

    Full Text Available A case of steroid-induced osteoporosis-related multiple fractures and dislocations are described after a seizure is reported. Patient had two years history of steroid use with no supplement or antiresorptive therapy. There was a delay in the diagnosis which affected an otherwise good outcome in such situations. It is recommended that patients on steroid should be given calcium, vitamin D, and an antiresorptive. Furthermore, a meticulous clinical examination is required in patients who are on steroids and suffer epileptic seizures to rule out skeletal injury.

  7. Intraocular lens dislocation after whole-body vibration.

    Science.gov (United States)

    Vela, José I; Andreu, David; Díaz-Cascajosa, Jesús; Buil, José A

    2010-10-01

    We present 2 cases of intraocular lens (IOL) dislocation that appeared shortly after the patients exercised on a vibration platform. The first patient was a 71-year-old woman who presented with lens subluxation in her right eye and a complete posterior IOL dislocation in her left eye. The second case was a 62-year-old woman who presented with unilateral IOL dislocation within the capsular bag in her right eye. Timing from IOL implantation to dislocation was approximately 6 years and 4 years, respectively. Pars plana vitrectomy with removal of the dislocated IOL was performed in both patients. Whole-body vibration training has become increasingly popular as a form of exercise training. It reportedly may provide benefits in physical function and in some diseases, especially in older people. However, evidence-based protocols ensuring safety and efficacy in this population are lacking. We discuss vibration as a cause of late IOL dislocation. Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  8. Dislocations and other topological oddities

    Science.gov (United States)

    Pieranski, Pawel

    2016-03-01

    We will show that the book Dislocations by Jacques Friedel, published half a century ago, can still be recommended, in agreement with the author's intention, as a textbook ;for research students at University and for students at engineering schools as well as for research engineers;. Indeed, today dislocations are known to occur not only in solid crystals but also in many other systems discovered more recently such as colloidal crystals or liquid crystals having periodic structures. Moreover, the concept of dislocations is an excellent starting point for lectures on topological defects occurring in systems equipped with order parameters resulting from broken symmetries: disclinations in nematic or hexatic liquid crystals, dispirations in chiral smectics or disorientations in lyotropic liquid crystals. The discussion of dislocations in Blue Phases will give us an opportunity to call on mind Sir Charles Frank, friend of Jacques Friedel since his Bristol years, who called these ephemeral mesophases ;topological oddities;. Being made of networks of disclinations, Blue Phases are similar to Twist Grain Boundary (TGB) smectic phases, which are made of networks of screw dislocations and whose existence was predicted by de Gennes in 1972 on the basis of the analogy between smectics and superconductors. We will stress that the book by Jacques Friedel contains seeds of this analogy.

  9. Closed reduction of displaced or dislocated mandibular condyle fractures in children using threaded Kirschner wire and external rubber traction.

    Science.gov (United States)

    Kim, J H; Nam, D H

    2015-10-01

    Most surgeons agree that closed treatment provides the best results for condylar fractures in children. Nevertheless, treatment of the paediatric mandibular condyle fracture that is severely displaced or dislocated is controversial. The purpose of this study was to investigate the long-term clinical and radiological outcomes following the treatment of displaced or dislocated condylar fractures in children using threaded Kirschner wire and external rubber traction. This procedure can strengthen the advantage of closed reduction and make up for the shortcomings of open reduction. From March 1, 2005 to December 25, 2011, 11 children aged between 4 and 12 years with displaced or dislocated mandibular condyle fractures were treated using threaded Kirschner wire and external rubber traction under portable C-arm fluoroscopy. All patients had unilateral displaced or dislocated condylar fractures. The follow-up period ranged from 24 to 42 months (mean 29.3 months). Normal occlusion and pain-free function of the temporomandibular joint, without deviation or limitation of jaw opening, was achieved in all patients. This closed reduction technique in displaced or dislocated condylar fractures in children offers a reliable solution in preventing the unfavourable sequelae of closed treatment and the open technique, such as altered morphology, functional disturbances, and facial nerve damage. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  10. Dislocations

    Science.gov (United States)

    ... Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español First Aid: ... bones become separated. Dislocations are caused by falls and hard impacts, such as in sports injuries, and are more common in teens than ...

  11. Dislocation dynamics in Al-Li alloys: mean jump distance and activation length of moving dislocations

    International Nuclear Information System (INIS)

    De Hosson, J.Th.M.; Huis Int Veld, A.

    1984-01-01

    It is pointed out that aluminum-lithium based alloys offer considerable promise for structural applications, especially in the aerospace industry. This promise is related to the potential for high strength in combination with a density which is lower than that found in conventional aluminum alloys. In addition, the modulus of elasticity is higher than corresponding values in conventional aluminum alloys. A nuclear magnetic resonance study of the mechanism of dislocation motion in Al-2.2 wt pct Li is reported. Information about the effective mean jump distance of mobile dislocations is provided by in situ nuclear spin relaxation measurements. The activation length of mobile dislocations has been obtained from strain-rate change experiments on Al-2.2 wt pct Li. The considered study shows that pulsed nuclear magnetic resonance is a complementary new technique for the study of moving dislocations in Al-Li alloys. 28 references

  12. Formation of dislocation dipoles in irradiated graphite

    International Nuclear Information System (INIS)

    Niwase, Keisuke

    2005-01-01

    Recently, we have proposed a dislocation dipole accumulation model to explain the irradiation-induced amorphization of graphite. However, the structure of dislocation dipole in the hexagonal networks is still an open question at the atomic-level. In this paper, we propose a possible formation process of the dislocation dipole

  13. Temporomandibular joint examination reviewed

    Directory of Open Access Journals (Sweden)

    L. Guarda Nardini

    2011-09-01

    Full Text Available The temporo-mandibular joint (TMJ it’s a joint closely related to the skull base, the spine, and the jaws; all these anatomical structures must be taken in consideration when evaluating pain involving the tmj. In order to detect patients affected by pathology or dysfunctions of the tmj, physical examination is of great value in orienting the diagnosis. Inspection must consider the symmetry of the body, the dental status and the type of occlusion. Palpation is a way to assess contractiont involving the muscles of the masticatory system and of the neck. Auscultation, based on articular noise provides means to determine whether we are dealing with degeneration of the joint or a dislocation of the intrarticular disc. In order to confirm the diagnosis obtained with the clinical evaluation, it’s useful to perform imaging techniques as opt, tomography and TC of the tmj and electromyokineosiography – index of the mandibular functionality and of the muscles status. MRI and dynamic MRI are among the non invasive exams which give the greatest amount of information, regarding the disc position and the joint degeneration. Arthroscopy is an invasive technique that allows early diagnosis of degeneration and is helpful to reveal early inflammatory processes of the joint.

  14. Distal radioulnar joint injuries

    Directory of Open Access Journals (Sweden)

    Binu P Thomas

    2012-01-01

    Full Text Available Distal radioulnar joint is a trochoid joint relatively new in evolution. Along with proximal radioulnar joint , forearm bones and interosseous membrane, it allows pronosupination and load transmission across the wrist. Injuries around distal radioulnar joint are not uncommon, and are usually associated with distal radius fractures,fractures of the ulnar styloid and with the eponymous Galeazzi or Essex_Lopresti fractures. The injury can be purely involving the soft tissue especially the triangular fibrocartilage or the radioulnar ligaments.The patients usually present with ulnar sided wrist pain, features of instability, or restriction of rotation. Difficulty in carrying loads in the hand is a major constraint for these patients. Thorough clinical examination to localize point of tenderness and appropriate provocative tests help in diagnosis. Radiology and MRI are extremely useful, while arthroscopy is the gold standard for evaluation. The treatment protocols are continuously evolving and range from conservative, arthroscopic to open surgical methods. Isolated dislocation are uncommon. Basal fractures of the ulnar styloid tend to make the joint unstable and may require operative intervention. Chronic instability requires reconstruction of the stabilizing ligaments to avoid onset of arthritis. Prosthetic replacement in arthritis is gaining acceptance in the management of arthritis.

  15. Imaging findings of anterior hip dislocations

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Kyle [Mallinckrodt Institute of Radiology, Department of Radiology, St. Louis, MO (United States); Leslie, Michael [Yale School of Medicine, Department of Orthopedics and Rehabilitation, New Haven, CT (United States); Menn, Kirsten; Haims, Andrew [Yale University School of Medicine, Department of Radiology and Biomedical Imaging, New Haven, CT (United States)

    2017-06-15

    Anterior hip dislocations are rare orthopedic emergencies resulting from high-energy trauma and have unique imaging characteristics on radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Imaging findings on CT and MRI allow for the prompt recognition and classification of anterior hip dislocations, which guides patient management and reduces complications. The purpose of this article is to review imaging findings of anterior hip dislocations, specifically focusing on CT and MRI. (orig.)

  16. Hyaluronic acid for the treatment of osteoarthritis in all joints except the knee: what is the current evidence?

    Science.gov (United States)

    Colen, Sascha; Haverkamp, Daniel; Mulier, Michiel; van den Bekerom, Michel P J

    2012-04-01

    The use of intra-articular hyaluronic acid (HA) is a well known treatment in patients with knee osteoarthritis (OA). In other joints, less evidence is available about the efficacy of treatment with intra-articular HA. HA is also used intra-articularly in the metatarsophalangeal-1 joint, the ankle, the hip, the sacroiliac joint, the facet joints, the carpometacarpal-1 joint, the shoulder and the temporo-mandibular joint. In this systematic review we include all prospective studies about the effects of intra-articular HA in the above-mentioned joints. Its use in the knee joint, however, will be discussed in a separate article in this journal. A systematic review was conducted using databases including MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Clinical Trial Register, and EMBASE. After performing a solid systematic review using a rigid methodology and trying to pool the outcomes of different studies, we noticed that, compared with baseline, there is statistical evidence for a positive effect of intra-articular HA. However, there is limited evidence HA is superior to placebo and no evidence that intra-articular HA is better than corticosteroids or other conservative therapies. Our recommendation for future research is that one should focus on adequately powered randomized trials comparing HA treatment with other types of intra-articular or conservative treatment. We think it is useless to further perform and publish (large) non-comparative prospective studies about the use of HA in the treatment of problems caused by OA. It is well perceived that HA exerts positive effects in the treatment of OA, but up to now there is no (strong) evidence available that HA is superior to other treatments of OA such as corticosteroids, physiotherapy or other conservative measures.

  17. High dislocation density of tin induced by electric current

    International Nuclear Information System (INIS)

    Liao, Yi-Han; Liang, Chien-Lung; Lin, Kwang-Lung; Wu, Albert T.

    2015-01-01

    A dislocation density of as high as 10 17 /m 2 in a tin strip, as revealed by high resolution transmission electron microscope, was induced by current stressing at 6.5 x 10 3 A/ cm 2 . The dislocations exist in terms of dislocation line, dislocation loop, and dislocation aggregates. Electron Backscattered Diffraction images reflect that the high dislocation density induced the formation of low deflection angle subgrains, high deflection angle Widmanstätten grains, and recrystallization. The recrystallization gave rise to grain refining

  18. High-temperature discrete dislocation plasticity

    Science.gov (United States)

    Keralavarma, S. M.; Benzerga, A. A.

    2015-09-01

    A framework for solving problems of dislocation-mediated plasticity coupled with point-defect diffusion is presented. The dislocations are modeled as line singularities embedded in a linear elastic medium while the point defects are represented by a concentration field as in continuum diffusion theory. Plastic flow arises due to the collective motion of a large number of dislocations. Both conservative (glide) and nonconservative (diffusion-mediated climb) motions are accounted for. Time scale separation is contingent upon the existence of quasi-equilibrium dislocation configurations. A variational principle is used to derive the coupled governing equations for point-defect diffusion and dislocation climb. Superposition is used to obtain the mechanical fields in terms of the infinite-medium discrete dislocation fields and an image field that enforces the boundary conditions while the point-defect concentration is obtained by solving the stress-dependent diffusion equations on the same finite-element grid. Core-level boundary conditions for the concentration field are avoided by invoking an approximate, yet robust kinetic law. Aspects of the formulation are general but its implementation in a simple plane strain model enables the modeling of high-temperature phenomena such as creep, recovery and relaxation in crystalline materials. With emphasis laid on lattice vacancies, the creep response of planar single crystals in simple tension emerges as a natural outcome in the simulations. A large number of boundary-value problem solutions are obtained which depict transitions from diffusional to power-law creep, in keeping with long-standing phenomenological theories of creep. In addition, some unique experimental aspects of creep in small scale specimens are also reproduced in the simulations.

  19. Help Desk Answers: Surgery vs conservative management for AC joint repair: How do the 2 compare?

    Science.gov (United States)

    Matchin, Bruce; Yee, Bruce; Mott, Timothy

    2016-04-01

    When not considering the grade of acromioclavicular (AC) joint dislocation, both conservative and surgical management lead to positive outcomes, although surgically managed patients require more time out of work.

  20. Electrical conduction along dislocations in plastically deformed GaN

    Energy Technology Data Exchange (ETDEWEB)

    Kamimura, Y; Yokoyama, T; Oiwa, H; Edagawa, K [Institute of Industrial Science, the University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505 (Japan); Yonenaga, I, E-mail: yasushi@iis.u-tokyo.ac.jp [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577 (Japan)

    2009-07-15

    Electrical conduction along dislocations in plastically deformed n-GaN single crystals has been investigated by scanning spread resistance microscopy (SSRM). In the SSRM images, many conductive spots have been observed, which correspond to electrical conduction along the dislocations introduced by deformation. Here, the introduced dislocations are b=(a/3)<1overline 210> edge dislocations parallel to the [0001] direction. The current values at the spots normalized to the background current value are larger than 100. Previous works have shown that grown-in edge dislocations in GaN are nonconductive. The high conductivity of the deformation-introduced edge dislocations in the present work suggests that the conductivity depends sensitively on the dislocation core structure.

  1. Rare Inferior Shoulder Dislocation (Luxatio Erecta)

    OpenAIRE

    Cift, Hakan; Soylemez, Salih; Demiroglu, Murat; Ozkan, Korhan; Ozden, Vahit Emre; Ozkut, Afsar T.

    2015-01-01

    Although shoulder dislocations have been seen very frequently, inferior dislocation of shoulder constitutes only 0.5% of all shoulder dislocations. We share our 4 patients with luxatio erecta and present their last clinical control. 2 male and 2 female Caucasian patients were diagnosed as luxatio erecta. Patients’ ages were 78, 62, 65, and 76. All patients’ reduction was done by traction-abduction and contour traction maneuver in the operating room. The patients had no symptoms and no limitat...

  2. Atomistically-informed dislocation dynamics in FCC crystals

    International Nuclear Information System (INIS)

    Martinez, E.; Marian, J.; Arsenlis, A.; Victoria, M.; Martinez, E.; Victoria, M.; Perlado, J.M.

    2008-01-01

    Full text of publication follows. We will present a nodal dislocation dynamics (DD) model to simulate plastic processes in fcc crystals. The model explicitly accounts for all slip systems and Burgers vectors observed in fcc systems, including stacking faults and partial dislocations. We derive simple conservation rules that describe all partial dislocation interactions rigorously and allow us to model and quantify cross-slip processes, the structure and strength of dislocation junctions, and the formation of fcc-specific structures such as stacking fault tetrahedra. The DD framework is built upon isotropic non-singular linear elasticity, and supports itself on information transmitted from the atomistic scale. In this fashion, connection between the meso and micro scales is attained self-consistently with core parameters fitted to atomistic data. We perform a series of targeted simulations to demonstrate the capabilities of the model, including dislocation reactions and dissociations and dislocation junction strength. Additionally we map the four-dimensional stress space relevant for cross-slip and relate our fundings to the plastic behaviour of' monocrystalline fcc metals. (authors)

  3. Creep Deformation by Dislocation Movement in Waspaloy.

    Science.gov (United States)

    Whittaker, Mark; Harrison, Will; Deen, Christopher; Rae, Cathie; Williams, Steve

    2017-01-12

    Creep tests of the polycrystalline nickel alloy Waspaloy have been conducted at Swansea University, for varying stress conditions at 700 °C. Investigation through use of Transmission Electron Microscopy at Cambridge University has examined the dislocation networks formed under these conditions, with particular attention paid to comparing tests performed above and below the yield stress. This paper highlights how the dislocation structures vary throughout creep and proposes a dislocation mechanism theory for creep in Waspaloy. Activation energies are calculated through approaches developed in the use of the recently formulated Wilshire Equations, and are found to differ above and below the yield stress. Low activation energies are found to be related to dislocation interaction with γ' precipitates below the yield stress. However, significantly increased dislocation densities at stresses above yield cause an increase in the activation energy values as forest hardening becomes the primary mechanism controlling dislocation movement. It is proposed that the activation energy change is related to the stress increment provided by work hardening, as can be observed from Ti, Ni and steel results.

  4. Dislocation Dynamics in Al-Li Alloys. Mean Jump Distance and Activation Length of Moving Dislocations

    NARCIS (Netherlands)

    Hosson, J.Th.M. De; Huis in 't Veld, A.; Tamler, H.; Kanert, O.

    1984-01-01

    Pulsed nuclear magnetic resonance proved to be a complementary new technique for the study of moving dislocations in Al-Li alloys. The NMR technique, in combination with transmission electron microscopy and strain-rate change experiments have been applied to study dislocation motion in Al-2.2 wt% Li

  5. Influence of mobile dislocations on phase separation in binary alloys

    International Nuclear Information System (INIS)

    Haataja, Mikko; Leonard, Francois

    2004-01-01

    We introduce a continuum model to describe the phase separation of a binary alloy in the presence of mobile dislocations. The kinetics of the local composition and dislocation density are coupled through their elastic fields. We show both analytically and numerically that mobile dislocations modify the standard spinodal decomposition process, and lead to several regimes of growth. Depending on the dislocation mobility and observation time, the phase separation may be accelerated, decelerated, or unaffected by mobile dislocations. For any finite dislocation mobility, we show that the domain growth rate asymptotically becomes independent of the dislocation mobility, and is faster than the dislocation-free growth rate

  6. Dislocation Interactions in Olivine Revealed by HR-EBSD

    Science.gov (United States)

    Wallis, David; Hansen, Lars N.; Britton, T. Ben; Wilkinson, Angus J.

    2017-10-01

    Interactions between dislocations potentially provide a control on strain rates produced by dislocation motion during creep of rocks at high temperatures. However, it has been difficult to establish the dominant types of interactions and their influence on the rheological properties of creeping rocks due to a lack of suitable observational techniques. We apply high-angular resolution electron backscatter diffraction to map geometrically necessary dislocation (GND) density, elastic strain, and residual stress in experimentally deformed single crystals of olivine. Short-range interactions are revealed by cross correlation of GND density maps. Spatial correlations between dislocation types indicate that noncollinear interactions may impede motion of proximal dislocations at temperatures of 1000°C and 1200°C. Long-range interactions are revealed by autocorrelation of GND density maps. These analyses reveal periodic variations in GND density and sign, with characteristic length scales on the order of 1-10 μm. These structures are spatially associated with variations in elastic strain and residual stress on the order of 10-3 and 100 MPa, respectively. Therefore, short-range interactions generate local accumulations of dislocations, leading to heterogeneous internal stress fields that influence dislocation motion over longer length scales. The impacts of these short- and/or long-range interactions on dislocation velocities may therefore influence the strain rate of the bulk material and are an important consideration for future models of dislocation-mediated deformation mechanisms in olivine. Establishing the types and impacts of dislocation interactions that occur across a range of laboratory and natural deformation conditions will help to establish the reliability of extrapolating laboratory-derived flow laws to real Earth conditions.

  7. Truly anatomic coracoclavicular ligament reconstruction with 2 Endobutton devices for acute Rockwood type V acromioclavicular joint dislocations.

    Science.gov (United States)

    Xue, Cheng; Song, Li-Jun; Zhang, Hao; Tang, Guo-Long; Li, Xiang; Fang, Jia-Hu

    2018-06-01

    Truly anatomic coracoclavicular ligament reconstruction (TACCR) according to the original insertions is a creative new method for the treatment of severe acromioclavicular separation. This research analyzed the clinical and radiologic results of TACCR in 25 patients with at least 2-year follow-up. The study enrolled 25 patients with Rockwood type V acromioclavicular joint dislocations who underwent TACCR using 2 Endobutton (Smith & Nephew Inc., Andover, MA, USA) devices from May 2013 to October 2015. Patients were assessed with clinical and radiologic follow-up at 3, 6, 12, 18, and 24 months postoperatively. The clinical assessments consisted of the visual analog scale and the Constant score. The radiographic evaluations were performed by measurements of the coracoclavicular distance. The mean follow-up was 34 ± 6.8 months (range, 24-48 months). The visual analog scale and Constant scores revealed significant advancements from 5 ± 0.9 (range, 4-7) and 45 ± 5.6 (range, 30-54) scores preoperatively to 0 ± 0.5 (range, 0-2) and 95 ± 2.9 (range, 91-98) scores at 24 months postoperatively, respectively. The coracoclavicular distance significantly decreased from 23 ± 5.4 mm (range, 16-34 mm) preoperatively to 8 ± 0.9 mm (range, 7-10 mm) at the final follow-up. TACCR represents a safe, reliable and creative surgical technique that yields good to excellent clinical and radiologic outcomes in the treatment of severe acromioclavicular separation. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  8. Low energy dislocation structures due to unidirectional deformation at low temperatures

    DEFF Research Database (Denmark)

    Hansen, Niels; Kuhlmann-Wilsdorf, D.

    1986-01-01

    The line energy of dislocations is {Gb2f(v)/4π} 1n(R/b) with R range of the dislocation stress field from the axis. This equation implies that quasi-uniform distributions are unstable relative to dislocation clusters in which neighboring dislocations mutually screen their stress fields, correspon......The line energy of dislocations is {Gb2f(v)/4π} 1n(R/b) with R range of the dislocation stress field from the axis. This equation implies that quasi-uniform distributions are unstable relative to dislocation clusters in which neighboring dislocations mutually screen their stress fields......, correspondingly leaving the major fraction of the volume free of dislocations. The value of R decreases in the following order: pile-ups to dipolar mats, Taylor lattices, tilt and dipolar walls to dislocation cell structures. This is the same order in which dislocation structures tend to develop with increasing...... dislocation density and hence increased dislocation interactions, leading to the corresponding energy decrease per unit length of dislocation line. Taking into consideration also the longer-range “termination stresses” of finite dislocation boundaries, and minimizing the total energy, explains the size...

  9. Electron-dislocation interaction at low temperatures. Progress report

    International Nuclear Information System (INIS)

    1976-01-01

    Studies of the interaction of mobile dislocations with electrons have shown that dislocation motion can be, in part, described by treating the dislocation as an underdamped oscillator. In particular, studies in lead alloys have shown tht dislocation motion can be considered as the motion of string, slightly damped by electrons, without regard for any other lattice friction. In addition we have shown that silver solutes, in lead crystals, occupy, partially, interstitial sites. Finally, we have shown that dislocations in copper interact, unexpectedly, with electrons. This is shown by measuring the influence of a magnetic field on the flow stress of copper crystals at 4.2 0 K

  10. What are the risk factors for dislocation in primary total hip arthroplasty? A multicenter case-control study of 128 unstable and 438 stable hips.

    Science.gov (United States)

    Fessy, M H; Putman, S; Viste, A; Isida, R; Ramdane, N; Ferreira, A; Leglise, A; Rubens-Duval, B; Bonin, N; Bonnomet, F; Combes, A; Boisgard, S; Mainard, D; Leclercq, S; Migaud, H

    2017-09-01

    an OR of 3.9 (95% CI: 2.15-7.1), history of spinal disease (lumbar stenosis, spinal fusion, discectomy, scoliosis and injury sequelae) with an OR of 1.89 (95% CI: 1.0-3.6), unrepaired joint capsule (all approaches) with an OR of 4.1 (95% CI: 2.3-7.37), unrepaired joint capsule (posterior approach) with an OR of 6.0 (95% CI: 2.2-15.9), and cup inclination outside Lewinnek's safe zone (30°-50°) with OR of 2.4 (95% CI: 1.4-4.0). This large comparative study isolated important patient-related factors for dislocation that surgeons must be aware of. We also found evidence that implanting the cup in 30° to 50° inclination has a major impact on preventing dislocation. Level III; case-control study. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  11. [Traumatic knee dislocation with popliteal vascular disruption: retrospective study of 14 cases].

    Science.gov (United States)

    Bonnevialle, P; Chaufour, X; Loustau, O; Mansat, P; Pidhorz, L; Mansat, M

    2006-12-01

    Complex femorotibial dislocation of the knee joint generally results from high-energy trauma caused by a traffic or a contact sport accident. Besides disruption of the cruciate ligaments, in 10-25% of patients present concomitant palsy of the common peroneal nerve and more rarely disruption of the popliteal artery. The purpose of this work was to assess outcome in a monocentric consecutive series of knee dislocations with ischemia due to disruption of the popliteal artery and to focus on specific aspects of management. This retrospective series included eleven men and three women, aged 18 to 74 years (mean 47 years). The right knee was injured in five and the left knee in six. Trauma resulted from a farm accident in six patients, fall from a high level in two, a traffic accident in three and a skiing accident (fall) in one. Two other patients with morbid obesity were fall victims. Nine patients had a single injury, two presented an associated serious head injury, one a severe chest injury, and one multiple trauma with coma, chest contusion, and abdominal lesions. One patient had a fracture of the distal femur with associated ischemia. Five knee dislocations were open with a popliteal wound for three and a posteromedial wound for two. Four patients presented total sciatic nerve palsy and nine palsy of the common peroneal nerve. The dislocation was documented in ten cases: lateral (n=1), anterior (n=4), posterior (n=5). For four patients, the dislocation had been reduced during pre-hospital care. Preoperative arteriography was available for eight patients and confirmed the disruption of the popliteal artery; the diagnosis was obvious in six other patients who were directed immediately to the operative theatre without pre-operative imaging. Revascularization was achieved with a upper popliteal-lower popliteal bypass using an inverted saphenous graft. The graft was harvested from the homolateral greater saphenous vein in eight patients and the contralateral vein in six

  12. Generalized dynamics of moving dislocations in quasicrystals

    International Nuclear Information System (INIS)

    Agiasofitou, Eleni; Lazar, Markus; Kirchner, Helmut

    2010-01-01

    A theoretical framework for dislocation dynamics in quasicrystals is provided according to the continuum theory of dislocations. Firstly, we present the fundamental theory for moving dislocations in quasicrystals giving the dislocation density tensors and introducing the dislocation current tensors for the phonon and phason fields, including the Bianchi identities. Next, we give the equations of motion for the incompatible elastodynamics as well as for the incompatible elasto-hydrodynamics of quasicrystals. We continue with the derivation of the balance law of pseudomomentum thereby obtaining the generalized forms of the Eshelby stress tensor, the pseudomomentum vector, the dynamical Peach-Koehler force density and the Cherepanov force density for quasicrystals. The form of the dynamical Peach-Koehler force for a straight dislocation is obtained as well. Moreover, we deduce the balance law of energy that gives rise to the generalized forms of the field intensity vector and the elastic power density of quasicrystals. The above balance laws are produced for both models. The differences between the two models and their consequences are revealed. The influences of the phason fields as well as of the dynamical terms are also discussed.

  13. Acromioclavicular dislocation type VI associated with diaphyseal fracture of the clavicle Luxação acromioclavicular tipo VI associada à fratura diafisária da clavícula

    Directory of Open Access Journals (Sweden)

    Evander Azevedo Grossi

    2013-01-01

    Full Text Available The purpose is to present a very unusual case of the acromioclavicular joint inferior dislocation associated with the clavicle fracture. It concerns to a young patient who had a bike fall and had this type of pathology, had been operated and obtained excellent clinic result. The literature mentions many cases of subcoracoide dislocation, but there are only two subacromial similar to ours. The case is described, a literary revision is done and discussed and the treatment is discussed.

  14. Biplanar fixation of acromio-clavicular joint dislocation associated with coracoid process fracture: Case report

    Directory of Open Access Journals (Sweden)

    Radwan G. Metwaly

    2018-06-01

    Full Text Available Introduction: Acromioclavicular (AC joint injury associated with coracoid process (CP fracture is a rare injury and only case reports had been published in the literature. Although AC joint injury is not uncommon, there is controversy as regard the best stabilization method whether to use wires, hook plate, arthroscopic reconstruction or the recently described techniques of anatomic restoration of both the coracoclavicular (CC and acromioclavicular (AC ligaments to add stability in both the vertical as well as the horizontal plane for the AC joint. Isolated CP fracture rarely necessitates surgical intervention; but in association with AC joint injury; a controversy as regard best management, surgical approach, technique of stabilization and implant used is present due to paucity of literature. Patient and method: A 36 years old manual worker who sustained a combined injury of AC joint (grade III and CP comminuted base fracture had been treated surgically in our hospital using a biplanar fixation technique; blind 4 mm cannulated screw for the CP fracture and anatomic reconstruction of the AC ligament using FibreTape (Arthrex, Naples, FL; to add stability in both the vertical and horizontal plane. Follow up was done for one year. Results: After completion of rehabilitation program, patient could return to work with no shoulder pain in ten weeks postoperatively. Till the last follow up there was no evidence of loss of reduction or shoulder pain with a Constant score of 86. Conclusion: Our technique in combined AC joint and CP fracture, address both injuries to add biplanar AC joint stability allowing accelerated rehabilitation and avoids metal hardware complications. Keywords: Acromioclavicular, Coracoid process, Anatomic reconstruction, And horizontal stability

  15. Molecular dynamics simulation of dislocations in uranium dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Fossati, Paul [CEA, DEN, DPC, SCCME, F-91191 Gif-sur-Yvette Cedex (France); Van Brutzel, Laurent, E-mail: laurent.vanbrutzel@cea.fr [CEA, DEN, DPC, SCCME, F-91191 Gif-sur-Yvette Cedex (France); Devincre, Benoît [LEM, CNRS-ONERA, 29 avenue de la Division Leclerc, F-92322 Châtillon Cedex (France)

    2013-11-15

    The plasticity of the fluorite structure in UO{sub 2} is investigated with molecular dynamics simulation and empirical potential. The stacking fault energies and the dislocation core structures with Burgers vector a/2 〈110〉 are systematically calculated. All dislocation core structures show a significant increase of the oxygen sub-lattice disorder at temperatures higher than 1500 K. The threshold stress for dislocation glide is found to decrease with increasing temperature but its values is always very high, several GPa at 0 K and several hundred of MPa at 2000 K. A relation between the dislocation mobility dependence with temperature and the increase of the oxygen sub-lattice disorder in the dislocation cores is established.

  16. Metastablity of the undissociated state of dissociated dislocations

    International Nuclear Information System (INIS)

    Takeuchi, Shin

    2005-01-01

    Undissociated, metastable dislocations have been observed in various crystals in addition to stable dissociated dislocations by high-resolution transmission electron microscopy. The origin of the metastablity of the undissociated state has been discussed specifically for the dissociation into Shockley partial dislocations in fcc or hcp lattice. It is shown that the metastability is due either to a high Peierls-Nabarro stress larger than a few percent of the shear modulus of the partial dislocations and/or to the increase of the total core energy by an increase of the dangling bonds. The metastablity of undissociated dislocations in zincblende III-V compounds is concluded to be due to a contribution of the latter effect

  17. Atomic-scale dislocation dynamics in radiation damage environment

    International Nuclear Information System (INIS)

    Osetsky, Y.; Stoller, R.; Bacon, D.J.

    2007-01-01

    Full text of publication follows: The dynamics behavior of dislocations determines mechanical properties of crystalline materials. Long-range interactions between a moving dislocation and other defects can be treated within a continuum approach via interaction of their stress and strain fields. However, a vast contribution to mechanical properties depends on the direct interaction between dislocations and other defects and depends very much on the particular atomic scale structure of the both moving dislocation core and the obstacle. In this work we review recent progress in large-scale modeling of dislocation dynamics in metals at the atomic level by molecular dynamics and statics. We review the modem techniques used to simulate dynamics of dislocations in different lattice structures, the dependence on temperature, strain rate and obstacle size. Examples are given for bcc, fcc and hcp metals where edge and screw dislocations interact with vacancy (loops, voids, stacking fault tetrahedra, etc), self-interstitial clusters and secondary phase precipitates. Attention is paid to interpretation of atomistic results from the point of view of parameterization of continuum models. The latter is vitally necessary for further application in 3-dimensional dislocation dynamics within the multi-scale materials modeling approach. Research sponsored by the Division of Materials Sciences and Engineering and the Office of Fusion Energy Sciences, U.S. Department of Energy, under contract DE-AC0S-00OR22725 with UT-Battelle, LLC. (authors)

  18. Medial epiphyseal fracture-detachment of the sternoclavicular joint with posterior displacement in a judo athlete - equivalent of posterior sternoclavicular dislocation

    Directory of Open Access Journals (Sweden)

    Rui Pimenta

    2013-04-01

    Full Text Available Posterior sternoclavicular dislocation is a rare traumatic injury that presents a potential risk of injury to mediastinal structures. The diagnosis is fundamentally clinical and treatment is done on an emergency basis. The authors report the clinical case of a young judo athlete with post-traumatic medial epiphyseal fracture-detachment, with posterior displacement (lesion equivalent to posterior sternoclavicular dislocation at pediatric ages. He underwent open reduction and ligament repair by means of a mini-anchor.The radiological and clinical outcome was excellent, and the athlete returned to his sports activity without limitations. We discuss the particular features of this pathological condition, along with the different therapeutic approaches and their complications

  19. Interactions between Dislocations and Grain Boundaries

    NARCIS (Netherlands)

    Soer, Wouter Anthon

    2006-01-01

    Dislocations (line defects) and grain boundaries (planar defects) are two types of lattice defects that are crucial to the deformation behavior of metals. Permanent deformation of a crystalline material is microscopically associated with the nucleation and propagation of dislocations, and extensive

  20. Hydrogen diffusion in the elastic fields of dislocations in iron

    Energy Technology Data Exchange (ETDEWEB)

    Sivak, A. B., E-mail: Sivak-AB@nrcki.ru; Sivak, P. A. [National Research Centre Kurchatov Institute (Russian Federation); Romanov, V. A.; Chernov, V. M. [National Research Tomsk State University (Russian Federation)

    2016-12-15

    The effect of dislocation stress fields on the sink efficiency thereof is studied for hydrogen interstitial atoms at temperatures of 293 and 600 K and at a dislocation density of 3 × 10{sup 14} m{sup –2} in bcc iron crystal. Rectilinear full screw and edge dislocations in basic slip systems 〈111〉(110), 〈111〉(112), 〈100〉(100), and 〈100〉(110) are considered. Diffusion of defects is simulated by means of the object kinetic Monte Carlo method. The energy of interaction between defects and dislocations is calculated using the anisotropic theory of elasticity. The elastic fields of dislocations result in a less than 25% change of the sink efficiency as compared to the noninteracting linear sink efficiency at a room temperature. The elastic fields of edge dislocations increase the dislocation sink efficiency, whereas the elastic fields of screw dislocations either decrease this parameter (in the case of dislocations with the Burgers vector being 1/2〈111〉) or do not affect it (in the case of dislocations with the Burgers vector being 〈100〉). At temperatures above 600 K, the dislocations affect the behavior of hydrogen in bcc iron mainly owing to a high binding energy between the hydrogen atom and dislocation cores.

  1. Nanoscale dislocation shear loops at static equilibrium and finite temperature

    Science.gov (United States)

    Dang, Khanh; Capolungo, Laurent; Spearot, Douglas E.

    2017-12-01

    Atomistic simulations are used to determine the resolved shear stress necessary for equilibrium and the resulting geometry of nanoscale dislocation shear loops in Al. Dislocation loops with different sizes and shapes are created via superposition of elemental triangular dislocation displacement fields in the presence of an externally imposed shear stress. First, a bisection algorithm is developed to determine systematically the resolved shear stress necessary for equilibrium at 0 K. This approach allows for the identification of dislocation core structure and a correlation between dislocation loop size, shape and the computed shear stress for equilibrium. It is found, in agreement with predictions made by Scattergood and Bacon, that the equilibrium shape of a dislocation loop becomes more circular with increasing loop size. Second, the bisection algorithm is extended to study the influence of temperature on the resolved shear stress necessary for stability. An approach is presented to compute the effective lattice friction stress, including temperature dependence, for dislocation loops in Al. The temperature dependence of the effective lattice friction stress can be reliably computed for dislocation loops larger than 16.2 nm. However, for dislocation loops smaller than this threshold, the effective lattice friction stress shows a dislocation loop size dependence caused by significant overlap of the stress fields on the interior of the dislocation loops. Combined, static and finite temperature atomistic simulations provide essential data to parameterize discrete dislocation dynamics simulations.

  2. A review of clinical and radiological aspects of rheumatoid arthritis of head joints

    International Nuclear Information System (INIS)

    Schilling, F.

    1987-01-01

    The most important inflammations--rheumatic joint diseases of the vertebral column--are chronic polyarthritis (rheumatoid arthritis) with involvement of cervical vertebral and atlanto-axial dislocation and ankylosing spondylitis (Bechterew's disease) resp. the seronegative spondylarthritis. A decisive and important difference between both forms of disease is found in the region of the cervical part of the vertebral column. In case of a spondylarthritis (ASp.) the ankylopoietica type includes the cervical vertebrae but the chronic polyarthritis (RA) is usually limited to the cervical vertebral spine. The incidence in both types (RA) is usually limited to the cervical vertebral spine. The incidence in both types (RA and ASp.) of cervical involvement is about 30%. The authors present an account of the underlying disease process. A description of rheumatoid cervical arthritis is given. The destructive and dislocating arthritis of the cranio-cervical function (arthritis of the head and neck joints) is described

  3. [Development of polyaxial locking plate screw system of sacroiliac joint].

    Science.gov (United States)

    Fan, Weijie; Xie, Xuesong; Zhou, Shuping; Zhang, Yonghu

    2014-09-01

    To develop an instrument for sacroiliac joint fixation with less injury and less complications. Firstly, 18 adult pelvic specimens (8 males and 10 females) were used to measure the anatomical data related to the locking plates and locking screws on the sacrum and ilium, and the polyaxial locking plate screw system of the sacroiliac joint was designed according to the anatomic data. This system was made of medical titanium alloy. Then 4 adult male plevic specimens were harvested and the experiment was divided into 3 groups: group A (normal pelvic), group B (the dislocated sacroiliac joint fixed with sacroiliac screws), and group C (the dislocated sacroiliac joint fixed with polyaxial locking plate screw system). The vertical displacement of sacroiliac joint under the condition of 0-700 N vertical load and the horizontal displacement on angle under the condition of 0-12 N·m torsional load were compared among the 3 groups by using the biological material test system. Finally, the simulated application test was performed on 1 adult male cadaveric specimen to observe soft tissue injury and the position of the locking plate and screw by X-ray films. According to the anatomic data of the sacrum and ilium, the polyaxial locking plate screw system of the sacroiliac joint was designed. The biomechanical results showed that the vertical displacement of the sacroiliac joint under the condition of 0-700 N vertical load in group A was significantly bigger than that in group B and group C (P 0.05). The horizontal displacement on angle under the condition of 0-12 N·m torsional load in group A was significantly less than that in group B and group C (P 0.05). The test of simulating application showed that the specimen suffered less soft tissue injury, and this instrument could be implanted precisely and safely. The polyaxial locking plate screw system of the sacroiliac joint has the advantages of smaller volume and less injury; polyaxial fixation enables flexible adjustment screw

  4. Work softening in nanocrystalline materials induced by dislocation annihilation

    DEFF Research Database (Denmark)

    Ungar, Tamas; Li, Li; Tichy, Geza

    2011-01-01

    Cold rolling reduces the quantity of dislocation densities in Ni–18% Fe alloys prepared by electrochemical deposition. The dislocation density evolution proposed earlier for the linearly decreasing work-hardening rate during stage III is revisited. The solution of the differential equation predicts...... that when the initial dislocation density is smaller or larger than the saturation value, then the dislocation density will increase or decrease during further plastic deformation. The predictions are verified by experimental values of dislocation densities determined by X-ray line-profile analysis....

  5. An irreducible ankle fracture dislocation: the Bosworth injury

    NARCIS (Netherlands)

    Schepers, Tim; Hagenaars, Tjebbe; den Hartog, Dennis

    2012-01-01

    Irreducible fracture dislocations of the ankle are rare and represent true orthopedic emergencies. We present a case of a fracture dislocation that was irreducible owing to a fixed dislocation of the proximal fibular fragment posterior to the lateral ridge of the tibia. This particular type of

  6. Dissociated dislocations in Ni: a computational study

    International Nuclear Information System (INIS)

    Szelestey, P.; Patriarca, M.; Kaski, K.

    2005-01-01

    A systematic computational study of the behavior of a (1/2) dissociated screw dislocation in fcc nickel is presented, in which atomic interactions are described through an embedded-atom potential. A suitable external stress is applied on the system, both for modifying the equilibrium separation distance d and moving the dislocation complex. The structure of the dislocation and its corresponding changes during the motion are studied in the framework of the two-dimensional Peierls model, for different values of the ratio d/a', where a' is the period of the Peierls potential. The distance between the edge and screw components of the partials, as well as their widths, undergo a modulation with period a', as the dislocation moves, and the amplitudes of such oscillations are shown to depend on d/a'. The stress profile acting on the dislocation complex is analyzed and the effective Peierls stress is estimated for different values of d/a'

  7. Dislocation density changes in nickel under creep

    International Nuclear Information System (INIS)

    Moiseeva, I.V.; Okrainets, P.N.; Pishchak, V.K.

    1984-01-01

    Variation in dislocation density was studied in the process of nickel creep p at t=900 deg c and σ=2 kgf/mm 2 . The dislocation structure was studied independently by the X-ray technique and transmission electron-microscopy. The e two methods show good conformity of results by comparison. It is concluded that independent determination of dislocation density under creep is possible us sing the X-ray technique

  8. Roentgenography of hip-joint using tubus in infants

    International Nuclear Information System (INIS)

    Sakuyama, Keiko; Imamura, Keiko; Uji, Teruyuki; Fujikawa, Mitsuhiro; Ishikawa, Toru

    1976-01-01

    Roentgenography of hip-joint using tubus was discussed. This technique has been made at St. Marianna University, School of Medicine, in order to reduce the exposure dose in x-ray examination of congenital dislocation of hip-joint. The tubus is designed to butterfly-shaped. Only the site which is necessary for roentgenography of hip-joint is exposed, and the sexual gland is outside exposure. The exposure dose of the sexual gland using tubus is 1/10 in female infants and 1/30 in male infants of those without tubus (6.7 mR in male infants, 2.0 mR in female infants). There are some advantages in the tubus: it is clinically used for both sexes as well as reducing exposure doses, and it can be used widely from neonates to infants. (Serizawa, K.)

  9. Lack of experience is a significant factor in the missed diagnosis of perilunate fracture dislocation or isolated dislocation

    Directory of Open Access Journals (Sweden)

    Ilker Çolak

    2018-01-01

    Conclusion: The results of this study indicated that lack of experience was the most important factor in the misdiagnosis of perilunate fracture dislocation or isolated dislocation. Level of Evidence: Level IV, diagnostic study.

  10. Stereo-radiographic analysis of loosening processes of alloplastic hip joint replacement

    International Nuclear Information System (INIS)

    Probst, K.J.

    1980-01-01

    A computer-aided diagnostic system has been developed by which implant dislocation of an order of 0.2 mm can be detected in all three dimensions. The diagnostic system is based on a point-by-point evaluation of stereoradiographic pictures; precise localisation of the implant relative to its place of insertion is made possible by special mathematical operations which are discussed in detail in the methodical part of the book. The method has been tested in clinical practice in 351 cases (208 patients) in the period between September 1, 1977, and May 31, 1979. By taking functional pictures during adduction and abduction of the extremity carrying the endoprosthesis and then evaluating these pictures, the diagnostic system can detect dislocations of the endoprosthesis inside the bone at a given moment. Also, the fate of hip joints with endoprostheses can be followed in the framework of longitudinal research. The method described here may also help to solve other problems of clinical relevance. The only precondition for this is the imaging of the structures of interest in the X-ray picture. A program to analyze loosening processes of alloplastic knee joint implants is new being worked on which will be of great use to the increasing number of patients with alloplastic knee joint implants. (orig./MG) [de

  11. Gradients of geometrically necessary dislocations from white beam microdiffraction

    International Nuclear Information System (INIS)

    Barabash, R.I.; Ice, G.E.; Pang, J.W.L.

    2005-01-01

    Variations in the local crystallographic orientation due to the presence of geometrically necessary dislocations and dislocation boundaries smear the distribution of intensity near Laue reflections. Here, some simple model distributions of geometrically necessary dislocations, GNDs, are used to estimate the dislocation tensor field from the intensity distribution of Laue peaks. Streaking of the Laue spots is found to be quantitatively and qualitatively distinct depending on the ratio between the absorption coefficient and the GND density gradient. In addition, different slip systems cause distinctly different Laue-pattern streaking. Experimental Laue patterns are therefore sensitive to stored dislocations and GNDs. As an example, white beam microdiffraction was applied to characterize the dislocation arrangement in a deformed polycrystalline Ni grain during in situ uniaxial tension

  12. Ultrasound as a probe of dislocation density in aluminum

    International Nuclear Information System (INIS)

    Mujica, Nicolás; Cerda, Maria Teresa; Espinoza, Rodrigo; Lisoni, Judit; Lund, Fernando

    2012-01-01

    Graphical abstract: Display Omitted - Abstract: Dislocations are at the heart of the plastic behavior of crystalline materials yet it is notoriously difficult to perform quantitative, non-intrusive measurements of their single or collective properties. Dislocation density is a critical variable that determines dislocation mobility, strength and ductility. On the one hand, individual dislocations can be probed in detail with transmission electron microscopy. On the other hand, their collective properties must be simulated numerically. Here we show that ultrasound technology can be used to measure dislocation density. This development rests on theory—a generalization of the Granato–Lücke theory for the interaction of elastic waves with dislocations—and resonant ultrasound spectroscopy (RUS) measurements. The chosen material is aluminum, to which different dislocation contents were induced through annealing and cold-rolling processes. The dislocation densities obtained with RUS compare favorably with those inferred from X-ray diffraction, using the modified Williamson–Hall method.

  13. Charcot joint-like changes following ankle fracture in a patient with no underlying disease: report of a rare case.

    Science.gov (United States)

    Kumagai, Masaru; Yokota, Kiyoshi; Endoh, Toshiya; Takemoto, Hitoshi; Nagata, Kensei

    2002-01-01

    Charcot joint is a disease that often occurs in patients with diabetes mellitus, tabes dorsalis, syringomyelia, chronic alcoholism, leprosy, trauma, or infection after fractures and dislocations. The treatment for Charcot joint has various complications, such as skin lesions, infections, and delayed union. We present our experience with a male patient who developed Charcot joint-like changes without diabetes mellitus or any other disease after an ankle fracture due to minor trauma.

  14. Midshaft clavicle fractures with associated ipsilateral acromioclavicular joint dislocations: Incidence and risk factors.

    Science.gov (United States)

    Ottomeyer, Christina; Taylor, Benjamin C; Isaacson, Mark; Martinez, Lara; Ebaugh, Pierce; French, Bruce G

    2017-02-01

    Simultaneous ipsilateral clavicle and acromioclavicular (AC) joint injury have been infrequently reported in the literature at this time. The purpose of this study was to assess incidence as well as assess risk factors for this dual injury pattern. We performed a retrospective review of a prospectively collected database (Level III evidence), evaluating 383 adult patients without previous shoulder girdle injury or trauma with a minimum 1-year follow-up who sustained a displaced diaphyseal clavicle fracture. All patients in the study underwent either nonoperative management or surgical reduction and stabilization of a diaphyseal clavicle fracture with a plate and screw construct. Study subjects were followed with serial radiographs. Clavicle and shoulder radiographs, as well as chest radiographs and contralateral films in questionable cases, were used to assess for acromioclavicular joint injury in both operative and nonoperative groups. Additional data was collected on concurrent injuries, patient demographics, fracture characteristics, fixation techniques, surgical/post-operative data, and operative or nonoperative treatment. We found that 13/183 (7.1%) of patients undergoing fixation of a diaphyseal clavicle fracture had an ipsilateral AC joint injury, while 13/200 (6.5%) of patients undergoing conservative management had an ipsilateral AC joint injury. Critical analysis of the data revealed that presence of ipsilateral scapular body fractures, and a likely incidental association with superior plating fixation, were associated with an increased rate of this injury pattern. Ipsilateral clavicle fracture and AC joint injury is much more common than traditionally believed, with an incidence of 6.8% overall. It is unknown how the presence of an associated AC injury influences outcome, as AC injury was not universally symptomatic. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Transition pathways in the unfaulting of dislocation loops

    International Nuclear Information System (INIS)

    Kubota, Alison; Wolfer, W.G.

    2005-01-01

    In order to study the dynamic mechanism of loop unfaulting, we performed large-scale classical molecular dynamics simulations involving computational cells with several millions of atoms. To induce dislocation loop unfaulting, we launched 1 ps duration traction stress pulses at a free surface of the computational box. In many cases, we observe unfaulting to involve both intuitive and complex dislocation processes with multiple Shockley partial dislocations. However, in some instances, we observe unfaulting to occur by a sudden instability of the stacking fault without clear traces of dislocation reactions

  16. Locked Central Fracture Dislocation of the Hip in a Child after Low-Energy Trauma

    Directory of Open Access Journals (Sweden)

    Alexandre H. Nehme

    2017-01-01

    Full Text Available We present the case of a 13-year-old boy who sustained a locked central fracture dislocation of the right acetabulum following a bicycle fall. Immediate external reduction maneuvers under general anesthesia were unsuccessful due to intrapelvic entrapment of the femoral head. Open reduction internal fixation was achieved 48 hours later. After an initial satisfactory postoperative course, the patient ended up developing severe hip osteoarthritis 16 months after the procedure. The rarity of this injury in children is discussed, with its possible implications on joint congruity and potential growth injury.

  17. Palmar dislocation of scaphoid and lunate

    Directory of Open Access Journals (Sweden)

    Khalid Koulali Idrissi

    2011-11-01

    Full Text Available A palmar dislocation of scaphoid and lunate is uncommon. We have found only 19 reported cases in the literature. We reported a simultaneous, divergent dislocation. The closed reduction followed by percutaneous pinning has given a good result without avascular necrosis of any carpal bone.

  18. Dislocation structure and cold resistance of low-carbon steel

    International Nuclear Information System (INIS)

    Gul', Yu.P.; Karnaukh, A.I.

    1975-01-01

    In the formation of the dislocation structure of a small (10%) deformation, the determining effect on the cold brittleness temperature is exerted by the degree of uniformity in the distribution of dislocations and microvolumes. The overall density of the dislocations is of secondary importance here. By pretreatment to achieve more uniform distribution and dispersion of particles of the excess phase, the degree of uniformity of dislocation distribution in microvolumes can be increased, the cold brittleness temperature lowered and the effect of various deformation patterns on resistance to cold counterbalanced. The formation of a cell-type dislocation structure in the case of a nonuniform distribution of relatively large particles of the excess phase and in that of a large overall density of dislocations does not result in low brittleness temperatures. The formation of a cell-type dislocation structure in the case of uniform distribution of particles of the excess phase and of a comparatively small overall density of dislocations is accompanied by a very pronounced decrease in cold brittleness temperature not only by comparison with other types of dislocation structure but also with the normalized state. At the same time the formation of this kind of a cell structure leads to a substantial (factor of 2-5) increase in resistance to plastic deformation. The prerequisites for obtaining an optimum dislocation are fulfilled either by a combination of hardening from the austenitic region and prompt, small-scale (5%) deformation, or by a combination of accelerated cooling from the austenitic region, 30-40% deformation and high yield. The size of the dislocation cells observed under the electron microscope does not exhibit - within the limits investigated - any direct effect on the cold brittleness temperature. (author)

  19. Dislocation defect interaction in irradiated Cu

    International Nuclear Information System (INIS)

    Schaeublin, R.; Yao, Z.; Spaetig, P.; Victoria, M.

    2005-01-01

    Pure Cu single crystals irradiated at room temperature to low doses with 590 MeV protons have been deformed in situ in a transmission electron microscope in order to identify the basic mechanisms at the origin of hardening. Cu irradiated to 10 -4 dpa shows at room temperature a yield shear stress of 13.7 MPa to be compared to the 8.8 MPa of the unirradiated Cu. Irradiation induced damage consists at 90% of 2 nm stacking fault tetrahedra, the remaining being dislocation loops and unidentified defects. In-situ deformation reveals that dislocation-defect interaction can take several forms. Usually, dislocations pinned by defects bow out under the applied stress and escape without leaving any visible defect. From the escape angles obtained at 183 K, an average critical stress of 100 MPa is deduced. In some cases, the pinning of dislocations leads to debris that are about 20 nm long, which formation could be recorded during the in situ experiment

  20. Prediction of dislocation boundary characteristics

    DEFF Research Database (Denmark)

    Winther, Grethe

    Plastic deformation of both fcc and bcc metals of medium to high stacking fault energy is known to result in dislocation patterning in the form of cells and extended planar dislocation boundaries. The latter align with specific crystallographic planes, which depend on the crystallographic......) and it is found that to a large extent the dislocations screen each other’s elastic stress fields [3]. The present contribution aims at advancing the previous theoretical analysis of a boundary on a known crystallographic plane to actual prediction of this plane as well as other boundary characteristics....... Crystal plasticity calculations combined with the hypothesis that these boundaries separate domains with local differences in the slip system activity are introduced to address precise prediction of the experimentally observed boundaries. The presentation will focus on two cases from fcc metals...

  1. Surgical treatment of traumatic cervical facet dislocation: anterior, posterior or combined approaches?

    Directory of Open Access Journals (Sweden)

    Catarina C. Lins

    Full Text Available ABSTRACT Surgical treatment is well accepted for patients with traumatic cervical facet joint dislocations (CFD, but there is uncertainty over which approach is better: anterior, posterior or combined. We performed a systematic literature review to evaluate the indications for anterior and posterior approaches in the management of CFD. Anterior approaches can restore cervical lordosis, and cause less postoperative pain and less wound problems. Posterior approaches are useful for direct reduction of locked facet joints and provide stronger fixation from a biomechanical point of view. Combined approaches can be used in more complex cases. Although both anterior and posterior approaches can be used interchangeably, there are some patients who may benefit from one of them over the other, as discussed in this review. Surgeons who treat cervical spine trauma should be able to perform both procedures as well as combined approaches to adequately manage CFD and improve patients’ final outcomes.

  2. Modeling of dislocation dynamics in germanium Czochralski growth

    Science.gov (United States)

    Artemyev, V. V.; Smirnov, A. D.; Kalaev, V. V.; Mamedov, V. M.; Sidko, A. P.; Podkopaev, O. I.; Kravtsova, E. D.; Shimansky, A. F.

    2017-06-01

    Obtaining very high-purity germanium crystals with low dislocation density is a practically difficult problem, which requires knowledge and experience in growth processes. Dislocation density is one of the most important parameters defining the quality of germanium crystal. In this paper, we have performed experimental study of dislocation density during 4-in. germanium crystal growth using the Czochralski method and comprehensive unsteady modeling of the same crystal growth processes, taking into account global heat transfer, melt flow and melt/crystal interface shape evolution. Thermal stresses in the crystal and their relaxation with generation of dislocations within the Alexander-Haasen model have been calculated simultaneously with crystallization dynamics. Comparison to experimental data showed reasonable agreement for the temperature, interface shape and dislocation density in the crystal between calculation and experiment.

  3. Mechanism of Strain Rate Effect Based on Dislocation Theory

    International Nuclear Information System (INIS)

    Kun, Qin; Shi-Sheng, Hu; Li-Ming, Yang

    2009-01-01

    Based on dislocation theory, we investigate the mechanism of strain rate effect. Strain rate effect and dislocation motion are bridged by Orowan's relationship, and the stress dependence of dislocation velocity is considered as the dynamics relationship of dislocation motion. The mechanism of strain rate effect is then investigated qualitatively by using these two relationships although the kinematics relationship of dislocation motion is absent due to complicated styles of dislocation motion. The process of strain rate effect is interpreted and some details of strain rate effect are adequately discussed. The present analyses agree with the existing experimental results. Based on the analyses, we propose that strain rate criteria rather than stress criteria should be satisfied when a metal is fully yielded at a given strain rate. (condensed matter: structure, mechanical and thermal properties)

  4. A case report of the management and the outcome of a complete epiphyseal separation and dislocation with left anterior column fracture of the acetabulum

    Directory of Open Access Journals (Sweden)

    Jesús Palencia

    2016-01-01

    Conclusion: Epiphyseal fracture with dislocation of the femoral head is rare among children and adolescents, especially when associated with an acetabular fracture. AVN in such cases can develop, and it represents a challenge to orthopedic surgeons due to the poor prognosis and the future functional limitations of the joint.

  5. Trapezium excision and suture suspensionplasty (TESS) for the treatment of thumb carpometacarpal arthritis.

    Science.gov (United States)

    Putnam, Matthew D; Meyer, Nicholas J; Baker, Daniel; Brehmer, Jess; Carlson, Brent D

    2014-06-01

    Basilar thumb arthritis, or first carpometacarpal arthritis, is a common condition affecting older women and some men. It is estimated that as many as one third of postmenopausal woman are affected. Surgical treatment of this condition includes options ranging from arthrodesis to prosthetic arthroplasty. Intermediate options include complete or partial trapezial excision with or without interposition of a cushioning/stabilizing material (auto source, allo source, synthetic source). A multitude of methods appear to offer similar end results, although some methods definitely involve more surgical work and perhaps greater patient risk. Through retrospective evaluation of a cohort of patients who underwent suture suspensionplasty, we determined the postoperative effect on strength, motion, patient satisfaction, complications, and radiographic maintenance of the scaphoid-metacarpal distance. This review shows the method to be clinically effective and, by comparison with a more traditional ligament reconstruction trapezial interposition arthroplasty, the method does not require use of autograft or allograft tendon and has fewer surgical steps. Forty-four patients were included in this retrospective study. The results showed that 91% of patients were satisfied with the procedure. Pinch and grip strength remained the same preoperatively and postoperatively. A Disabilities of the Arm, Shoulder, and Hand patient-reported outcome instrument (DASH) scores averaged 30 at final follow-up. Three patients developed a late complication requiring further surgical intervention. In summary, this technique appears to be technically reproducible, requires no additional tendon material, and achieves objectively and subjectively similar results to other reported procedures used to manage first CMC Arthritis.

  6. Piles of dislocation loops in real crystals

    International Nuclear Information System (INIS)

    Dubinko, V.I.; Turkin, A.A.; Yanovskij, V.V.

    1985-01-01

    Behaviour of piles of dislocation loops in crystals was studied in order to define metal swelling under irradiation. Energy of pile interaction with point defects and intrinsic pile energy are studied in the framework of the linear elasticity theory. Preference of dislocation pile calculated in the paper decreases with radiation dose hence, material swelling rate also decreases. Creation of conditions, which assume an existence of piles of dislocation loops being stable under irradiation, is of particular interest

  7. Electron-dislocation interaction at low temperatures. Progress report

    International Nuclear Information System (INIS)

    1978-01-01

    The interaction of mobile dislocations with electrons in copper and copper alloys has shown that dislocation motion in copper, at low temperature, can be treated as an analog of an underdamped oscillator. We have also shown that the viscous drag on mobile dislocations in type II superconductors can be treated as an acoustic attenuation of an elastic wave

  8. Formation of disorientations in dislocation structures during plastic deformation

    DEFF Research Database (Denmark)

    Pantleon, W.

    2002-01-01

    Disorientations developing during plastic deformation in dislocation structures are investigated. Based on expected mechanisms for the formation of different types of dislocation boundaries (statistical trapping of dislocations or differently activated slip systems) the formation of the disorient...

  9. Value of tomosynthesis for lesion evaluation of small joints in osteoarthritic hands using the OARSI score.

    Science.gov (United States)

    Martini, K; Becker, A S; Guggenberger, R; Andreisek, G; Frauenfelder, T

    2016-07-01

    To determine the diagnostic performance of tomosynthesis in depicting osteoarthritic lesions in comparison to conventional radiographs, with use of computed tomography (CT) as standard-of-reference. Imaging of 12 cadaveric hands was performed with tomosynthesis in dorso-palmar (dp) projection, conventional radiographs (dp) and multi-detector CT. Distal interphalangeal joint (DIP)II, DIPIII, proximal interphalangeal joint (PIP)II, PIPIII, first carpometacarpal (CMC) and scaphotrapezotrapezoidal joint (STT) were graded by two independent readers using the Osteoarthritis Research Society International (OARSI) score. The mean score for each feature was calculated for all modalities. Additional wrists were evaluated for presence of calcium pyrophosphate disease (CPPD). CT served as reference-standard. Inter-reader agreement (ICC) was calculated. Comparing tomosynthesis and conventional radiographs to CT, the sensitivity for the presence of osteophytes was 95,7% vs 65,2%; for joint space narrowing 95,8% vs 52,1%; for subchondral sclerosis 61,5% vs 51,3%; for lateral deformity 83.3% vs 83,3%; and for subchondral cysts 45,8% vs 29,2%. Erosions were not present. While tomosynthesis showed no significant difference in OARSI score grading to CT (mean OARSI-score CT: 16.8, SD = 10.6; mean OARSI-score Tomosynthesis: 16.3, SD = 9.6; P = 0.84), conventional radiographs had significant lower mean OARSI scores (mean OARSI-score X-ray: 11.1, SD = 8.3; P = 0.04). Inter-reader agreement for OARSI scoring was excellent (ICC = 0.99). CPPD calcifications present in CT, were also visible with tomosynthesis, but not with conventional radiography. In conclusion, tomosynthesis depicts more osteoarthritic changes in the small joints of the hand than conventional radiography using the OARSI scoring system and CT as the standard of reference. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  10. Thermodynamic theory of dislocation-enabled plasticity

    International Nuclear Information System (INIS)

    Langer, J. S.

    2017-01-01

    The thermodynamic theory of dislocation-enabled plasticity is based on two unconventional hypotheses. The first of these is that a system of dislocations, driven by external forces and irreversibly exchanging heat with its environment, must be characterized by a thermodynamically defined effective temperature that is not the same as the ordinary temperature. The second hypothesis is that the overwhelmingly dominant mechanism controlling plastic deformation is thermally activated depinning of entangled pairs of dislocations. This paper consists of a systematic reformulation of this theory followed by examples of its use in analyses of experimentally observed phenomena including strain hardening, grain-size (Hall-Petch) effects, yielding transitions, and adiabatic shear banding.

  11. Treatment of recurrent patellar dislocation via knee arthroscopy combined with C-arm fluoroscopy and reconstruction of the medial patellofemoral ligament.

    Science.gov (United States)

    Li, Li; Wang, Hongbo; He, Yun; Si, Yu; Zhou, Hongyu; Wang, Xin

    2018-06-01

    Recurrent patellar dislocations were treated via knee arthroscopy combined with C-arm fluoroscopy, and reconstruction of the medial patellofemoral ligaments. Between October 2013 and March 2017, 52 cases of recurrent patellar dislocation [27 males and 25 females; age, 16-47 years (mean, 21.90 years)] were treated. Arthroscopic exploration was performed and patellofemoral joint cartilage injuries were repaired. It was subsequently determined whether it was necessary to release the lateral patellofemoral support belt. Pre-operative measurements were used to decide whether tibial tubercle osteotomy was required. Medial patellofemoral ligaments were reconstructed using autologous semitendinosus tendons. Smith and Nephew model 3.5 line anchors were used to double-anchor the medial patellofemoral margin. On the femoral side, the medial patellofemoral ligament was fixed using 7-cm, absorbable, interfacial compression screws. All cases were followed for 1-40 months (average, 21 months). The Q angle, tibial tuberosity trochlear groove distance, Insall-Salvati index, patellofemoral angle, lateral patellofemoral angle and lateral shift were evaluated on X-Ray images using the picture archiving and communication system. Subjective International Knee Documentation Committee (IKDC) knee joint functional scores and Lysholm scores were recorded. Post-operative fear was absent, and no patellar re-dislocation or re-fracture was noted during follow-up. At the end of follow-up, the patellofemoral angle (0.22±4.23°), lateral patellofemoral angle (3.44±1.30°), and lateral shift (0.36+0.14°) differed significantly from the pre-operative values (all, Ppatellofemoral ligament was effective.

  12. Pair Interaction of Dislocations in Two-Dimensional Crystals

    Science.gov (United States)

    Eisenmann, C.; Gasser, U.; Keim, P.; Maret, G.; von Grünberg, H. H.

    2005-10-01

    The pair interaction between crystal dislocations is systematically explored by analyzing particle trajectories of two-dimensional colloidal crystals measured by video microscopy. The resulting pair energies are compared to Monte Carlo data and to predictions derived from the standard Hamiltonian of the elastic theory of dislocations. Good agreement is found with respect to the distance and temperature dependence of the interaction potential, but not regarding the angle dependence where discrete lattice effects become important. Our results on the whole confirm that the dislocation Hamiltonian allows a quantitative understanding of the formation and interaction energies of dislocations in two-dimensional crystals.

  13. Dislocation Structures in Creep-deformed Polycrystalline MgO

    DEFF Research Database (Denmark)

    Bilde-Sørensen, Jørgen

    1972-01-01

    dislocation segments lie in their slip or climb planes. On the basis of this structure, a model is proposed in which glide is the principal cause of deformation but the rate-limiting process, i.e. annealing of the network, is diffusion-controlled. Theoretical estimates and experimental results agree within 1...... energy of 76 ± 12 kcal/mol. The creep rate is independent of grain size. The dislocation structure was investigated by transmission electron microscopy. The total dislocation density follows the relation, σ=bG√ρ, commonly found for metals. The dislocations form a 3-dimensional network in which many...

  14. Thermal activation of dislocations in large scale obstacle bypass

    Science.gov (United States)

    Sobie, Cameron; Capolungo, Laurent; McDowell, David L.; Martinez, Enrique

    2017-08-01

    Dislocation dynamics simulations have been used extensively to predict hardening caused by dislocation-obstacle interactions, including irradiation defect hardening in the athermal case. Incorporating the role of thermal energy on these interactions is possible with a framework provided by harmonic transition state theory (HTST) enabling direct access to thermally activated reaction rates using the Arrhenius equation, including rates of dislocation-obstacle bypass processes. Moving beyond unit dislocation-defect reactions to a representative environment containing a large number of defects requires coarse-graining the activation energy barriers of a population of obstacles into an effective energy barrier that accurately represents the large scale collective process. The work presented here investigates the relationship between unit dislocation-defect bypass processes and the distribution of activation energy barriers calculated for ensemble bypass processes. A significant difference between these cases is observed, which is attributed to the inherent cooperative nature of dislocation bypass processes. In addition to the dislocation-defect interaction, the morphology of the dislocation segments pinned to the defects play an important role on the activation energies for bypass. A phenomenological model for activation energy stress dependence is shown to describe well the effect of a distribution of activation energies, and a probabilistic activation energy model incorporating the stress distribution in a material is presented.

  15. Dechanneling by dislocation loops

    International Nuclear Information System (INIS)

    Chalant, Gerard.

    1976-09-01

    Ion implantation always induces the creation of dislocation loops. When the damage profile is determined by a backscattering technique, the dechanneling by these loops is implicitely at the origin of these measurements. The dechanneling of alpha particles by dislocation loops produced by the coalescence of quenched-in vacancies in aluminium is studied. The dechanneling and the concentration of loops were determined simultaneously. The dechanneling width around dislocation was found equal to lambda=6A, both for perfect and imperfect loops having a mean diameter d=250A. In the latter case, a dechanneling probability chi=0.34 was determined for the stacking fault, in good agreement with previous determination in gold. A general formula is proposed which takes into account the variation of lambda with the curvature (or the diameter d) of the loops. Finally, by a series of isothermal anneals, the self-diffusion energy ΔH of aluminium was measured. The value obtained ΔH=1.32+-0.10eV is in good agreement with the values obtained by other methods [fr

  16. Loss of reduction and complications of coracoclavicular ligament reconstruction with autogenous tendon graft in acute acromioclavicular dislocations.

    Science.gov (United States)

    Choi, Nam Hong; Lim, Seok Min; Lee, Sang Young; Lim, Tae Kang

    2017-04-01

    This study was conducted to report loss of reduction and complications after single-tunnel coracoclavicular (CC) ligament reconstruction with autogenous semitendinosus tendon graft for acute acromioclavicular (AC) joint dislocations. This retrospective study included patients with acute, unstable AC dislocations (surgery within 6 weeks after trauma). We excluded patients with chronic injury and distal clavicle fractures with CC ligaments disruption. We measured the CC distance on anteroposterior radiographs of both clavicles, preoperatively, immediately postoperatively, and at the final follow-up visit. We evaluated clinical outcomes using the American Shoulder and Elbow Surgeons Shoulder Assessment and the University of California, Los Angeles Shoulder Rating Scale scores and perioperative complications. There were 30 patients (27 men and 3 women) with mean age of 41 years (range, 19-70 years). The mean follow-up period was 31 months (range, 12-186 months). Mean CC distance was 15.5 ± 3.7 mm (84% ± 14% of the contralateral shoulder) preoperatively, 8.9 ± 2.6 mm (9% ± 40%) immediately postoperatively (P 25% increase of CC distance) developed in 14 patients (47%), and complications occurred in 6 patients (20%), including 3 distal clavicle fractures through the tunnel. Final clinical scores were significantly lower in patients with complications (27 vs. 33 of the University of California, Los Angeles assessment [P < .001] and 81 vs. 95 of the American Shoulder and Elbow Surgeons Shoulder assessment [P < .001]). In acute AC joint dislocation, single-tunnel CC ligament reconstruction using autogenous tendon graft resulted in loss of reduction rate of 47% and a complication rate of 20%. The development of complications adversely affected clinical outcomes. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  17. Lens dislocation has a possible relationship with laser iridotomy

    Directory of Open Access Journals (Sweden)

    Mutoh T

    2012-12-01

    Full Text Available Tetsuya Mutoh,1,2 Kevin F Barrette,2 Yukihiro Matsumoto,1 Makoto Chikuda11Department of Ophthalmology, Dokkyo Medical University Koshigaya Hospital, Koshigaya City, Saitama, Japan; 2Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USAAbstract: We report our recent experience of four eyes with spontaneous lens dislocation in four patients with no history of trauma or any systemic disease associated with zonular dialysis. Lens dislocation developed with 0.5 to 6 months following laser iridotomy. All patients were male and two eyes were complicated with acute primary angle closure glaucoma preoperatively. Case 1 showed bilateral lens dislocation, while cases 2 and 3 involved unilateral lens dislocation. Cases 2 and 3 showed lenses completely dislocated into the vitreous cavity. All cases needed lens removal and scleral fixation of intraocular lenses. Final visual acuity was 1.2 in all cases. We suspect that laser iridotomy may induce localized zonular dialysis that results in progressive zonular weakness, leading to lens dislocation.Keywords: lens dislocation, laser iridotomy, primary angle closure glaucoma

  18. Thermally activated dislocation motion including inertial effects in solid solutions

    International Nuclear Information System (INIS)

    Isaac, R.D.

    1977-01-01

    Dislocation motion through an array of obstacles is considered in terms of the potential energy of the dislocation as it moves through the array. The obstacles form a series of potential wells and barriers which can trap the dislocations. The effect of thermal fluctuations and of a viscous drag on the motion of the dislocation is investigated by analogy with Brownian motion in a field of force. The rate of escape of a trapped dislocation is found to depend on the damping coefficient only for a large viscous drag. The probability that a dislocation will be trapped by a well or barrier is found to depend on the damping coefficient for a small viscous drag. This inertial effect determines how far a dislocation will travel after breaking away from an obstacle

  19. Influence of strain on dislocation core in silicon

    Science.gov (United States)

    Pizzagalli, L.; Godet, J.; Brochard, S.

    2018-05-01

    First principles, density functional-based tight binding and semi-empirical interatomic potentials calculations are performed to analyse the influence of large strains on the structure and stability of a 60? dislocation in silicon. Such strains typically arise during the mechanical testing of nanostructures like nanopillars or nanoparticles. We focus on bi-axial strains in the plane normal to the dislocation line. Our calculations surprisingly reveal that the dislocation core structure largely depends on the applied strain, for strain levels of about 5%. In the particular case of bi-axial compression, the transformation of the dislocation to a locally disordered configuration occurs for similar strain magnitudes. The formation of an opening, however, requires larger strains, of about 7.5%. Furthermore, our results suggest that electronic structure methods should be favoured to model dislocation cores in case of large strains whenever possible.

  20. [Short-term effectiveness of Swanson artificial joint replacement in treating posttraumatic metacarpophalangeal joint stiffness].

    Science.gov (United States)

    Lu, Hui; Shen, Xiangqian; Xu, Jihua; Huang, Xin; Ye, Po; Wu, Shoucheng

    2011-11-01

    To investigate the short-term effectiveness of Swanson artificial joint replacement in treating post-traumatic metacarpophalangeal joint stiffness. Between August 2007 and May 2010, 11 cases (13 fingers) of metacarpophalangeal joint stiffness with soft tissue defects underwent Swanson artificial joint replacement. There were 7 males (9 fingers) and 4 females (4 fingers), aged 43 to 65 years with an average of 49 years. The involved fingers included 4 thumbs, 4 index fingers, 3 middle fingers, and 2 ring fingers. The types of injury included open and crush injury in 8 fingers, fracture of the metacarpophalangeal joint in 3 fingers, metacarpophalangeal joint severing in 2 fingers. The time from joint stiffness to hospitalization was 12 to 48 weeks (mean, 24 weeks). The joint activity was (136.82 +/- 28.96) degrees. According to total active motion (TAM) assessment, included good in 1 finger, fair in 6 fingers, and poor in 6 fingers before operation. The activities of daily living were assessed by Sollerman score, which was 45.64 +/- 11.04. The X-ray films and CT scan showed traumatic arthritis of the metacarpophalangeal joint. The incision healed by first intention. All patients were followed up 12 to 34 months (mean, 24.1 months). At last follow-up, the joint activity was (194.64 +/- 28.86) degrees, showing significant difference when compared with preoperative value (t = 25.214, P = 0.000). According to TAM assessment, including excellent in 1 finger, good in 4 fingers, fair in 7 fingers, and poor in 1 finger. The Sollerman score was 67.45 +/- 8.20 postoperatively, showing significant difference when compared with the preoperative score (t = -10.470, P = 0.000). X-ray examination showed no prosthesis fracture, periprosthetic fracture, or joint dislocation occurred at last follow-up. Swanson artificial joint replacement can be applied to treat post-traumatic metacarpophalangeal joint stiffness, which can improve the joint activity and has satisfactory short

  1. Riemann–Cartan Geometry of Nonlinear Dislocation Mechanics

    KAUST Repository

    Yavari, Arash; Goriely, Alain

    2012-01-01

    but vanishing non-metricity. Torsion of the material manifold is identified with the dislocation density tensor of nonlinear dislocation mechanics. Using Cartan's moving frames we construct the material manifold for several examples of bodies with distributed

  2. Magnetic resonance findings in knee dislocation: pictorial essay

    International Nuclear Information System (INIS)

    Coates, M.; Stewart, N.; Morganti, V.; Twaddle, B.

    2000-01-01

    The role of MRI in the preoperative assessment of knee dislocation is well documented. e present our experience with a series of images graphically displaying the spectrum of abnormalities associated with these injuries. These images were derived from a local internal audit reviewing the preoperative MRI and correlating this with the surgical findings. Twenty-two cases between April 1997 and April 1999 were reviewed. Traumatic dislocation of the knee is rare, although many believe it is often unrecognized because of spontaneous reduction.' The injury may present as (i) frank dislocation; (ii) a knee that is dislocated while under anaesthesia; or (iii) a pattern of soft-tissue injury which suggests dislocation. Dislocation is described by the position of the tibia relative to the femur and may be anterior, posterior, lateral, medial or rotatory. Conservative management has traditionally been advocated and in this setting clinical examination and plain radiographs are adequate. Because of the trend toward increased surgical intervention, however, the more accurate characterization of soft-tissue injuries provided by MRI aids the planning of ligamentous reconstruction and the operative approach. Copyright (1999) Blackwell Science Pty Ltd

  3. On verification of a theory in dislocation plasticity

    International Nuclear Information System (INIS)

    Ng, D.H.Y.; Lee, L.H.N.

    1981-01-01

    In the past twenty years, many attempts to unify the theories of macroplasticity and microplasticity in polycrystalline materials have been made. Several major approaches have been suggested namely: the geometrical approach, the analytical approach, the phenomenological approach and the internal variables approach. To verify the plasticity theory based on any one of the above models, detail experimental data including microstructural quantities such as dislocation density, dislocation speed, etc. are required. Unfortunately, there were some difficulties in evaluating dislocation speed and dealing with the term 'mobile fraction' of dislocation density. Therefore, an experimental verification of such plasticity theory has not been made. A dislocation velocity equation based on a thermally activated model is used. A set of plastic strain rate equations for polycrystalline materials formulated by analyzing dislocation dynamics in a statistical approach are presented. In order to evaluate the activation free energy, Gibbs' modified tetragonal distortion model is used together with some measurements obtained from electron micrographs. Experimental results on the dynamic yielding and fracture of 6061-T6 aluminum alloy tubings under biaxial loadings obtained by Ng, Delich and Lee are used. In dealing with 'mobile fraction', Gilman's suggestion is adopted. (orig./HP)

  4. Dislocation core structures in (0001) InGaN

    International Nuclear Information System (INIS)

    Rhode, S. L.; Sahonta, S.-L.; Kappers, M. J.; McAleese, C.; Humphreys, C. J.; Horton, M. K.; Haigh, S. J.; Pennycook, T. J.; Dusane, R. O.; Moram, M. A.

    2016-01-01

    Threading dislocation core structures in c-plane GaN and In x Ga 1−x N (0.057 ≤ x ≤ 0.20) films were investigated by aberration-corrected scanning transmission electron microscopy. a-type dislocations are unaffected by alloying with indium and have a 5/7-atom ring core structure in both GaN and In x Ga 1−x N. In contrast, the dissociation lengths of (a + c)-type dislocations are reduced, and new 7/4/9-atom ring and 7/4/8/5-atom ring core structures were observed for the dissociated (a + c)-type dislocations in In x Ga 1−x N, which is associated with the segregation of indium near (a + c)-type and c-type dislocation cores in In x Ga 1−x N, consistent with predictions from atomistic Monte Carlo simulations.

  5. Strain field mapping of dislocations in a Ge/Si heterostructure.

    Directory of Open Access Journals (Sweden)

    Quanlong Liu

    Full Text Available Ge/Si heterostructure with fully strain-relaxed Ge film was grown on a Si (001 substrate by using a two-step process by ultra-high vacuum chemical vapor deposition. The dislocations in the Ge/Si heterostructure were experimentally investigated by high-resolution transmission electron microscopy (HRTEM. The dislocations at the Ge/Si interface were identified to be 90° full-edge dislocations, which are the most efficient way for obtaining a fully relaxed Ge film. The only defect found in the Ge epitaxial film was a 60° dislocation. The nanoscale strain field of the dislocations was mapped by geometric phase analysis technique from the HRTEM image. The strain field around the edge component of the 60° dislocation core was compared with those of the Peierls-Nabarro and Foreman dislocation models. Comparison results show that the Foreman model with a = 1.5 can describe appropriately the strain field around the edge component of a 60° dislocation core in a relaxed Ge film on a Si substrate.

  6. Strain field mapping of dislocations in a Ge/Si heterostructure.

    Science.gov (United States)

    Liu, Quanlong; Zhao, Chunwang; Su, Shaojian; Li, Jijun; Xing, Yongming; Cheng, Buwen

    2013-01-01

    Ge/Si heterostructure with fully strain-relaxed Ge film was grown on a Si (001) substrate by using a two-step process by ultra-high vacuum chemical vapor deposition. The dislocations in the Ge/Si heterostructure were experimentally investigated by high-resolution transmission electron microscopy (HRTEM). The dislocations at the Ge/Si interface were identified to be 90° full-edge dislocations, which are the most efficient way for obtaining a fully relaxed Ge film. The only defect found in the Ge epitaxial film was a 60° dislocation. The nanoscale strain field of the dislocations was mapped by geometric phase analysis technique from the HRTEM image. The strain field around the edge component of the 60° dislocation core was compared with those of the Peierls-Nabarro and Foreman dislocation models. Comparison results show that the Foreman model with a = 1.5 can describe appropriately the strain field around the edge component of a 60° dislocation core in a relaxed Ge film on a Si substrate.

  7. Rare Inferior Shoulder Dislocation (Luxatio Erecta

    Directory of Open Access Journals (Sweden)

    Hakan Cift

    2015-01-01

    Full Text Available Although shoulder dislocations have been seen very frequently, inferior dislocation of shoulder constitutes only 0.5% of all shoulder dislocations. We share our 4 patients with luxatio erecta and present their last clinical control. 2 male and 2 female Caucasian patients were diagnosed as luxatio erecta. Patients’ ages were 78, 62, 65, and 76. All patients’ reduction was done by traction-abduction and contour traction maneuver in the operating room. The patients had no symptoms and no limitation of range of motion of their shoulder at their last control. Luxatio erecta is seen rarely, and these patients may have neurovascular injury. These patients should be carefully examined and treated by the orthopaedic and traumatology surgeons.

  8. Rare Inferior Shoulder Dislocation (Luxatio Erecta)

    Science.gov (United States)

    Cift, Hakan; Soylemez, Salih; Demiroglu, Murat; Ozkan, Korhan; Ozden, Vahit Emre; Ozkut, Afsar T.

    2015-01-01

    Although shoulder dislocations have been seen very frequently, inferior dislocation of shoulder constitutes only 0.5% of all shoulder dislocations. We share our 4 patients with luxatio erecta and present their last clinical control. 2 male and 2 female Caucasian patients were diagnosed as luxatio erecta. Patients' ages were 78, 62, 65, and 76. All patients' reduction was done by traction-abduction and contour traction maneuver in the operating room. The patients had no symptoms and no limitation of range of motion of their shoulder at their last control. Luxatio erecta is seen rarely, and these patients may have neurovascular injury. These patients should be carefully examined and treated by the orthopaedic and traumatology surgeons. PMID:25883820

  9. Asymptotic analysis of a pile-up of regular edge dislocation walls

    KAUST Repository

    Hall, Cameron L.

    2011-12-01

    The idealised problem of a pile-up of regular dislocation walls (that is, of planes each containing an infinite number of parallel, identical and equally spaced dislocations) was presented by Roy et al. [A. Roy, R.H.J. Peerlings, M.G.D. Geers, Y. Kasyanyuk, Materials Science and Engineering A 486 (2008) 653-661] as a prototype for understanding the importance of discrete dislocation interactions in dislocation-based plasticity models. They noted that analytic solutions for the dislocation wall density are available for a pile-up of regular screw dislocation walls, but that numerical methods seem to be necessary for investigating regular edge dislocation walls. In this paper, we use the techniques of discrete-to-continuum asymptotic analysis to obtain a detailed description of a pile-up of regular edge dislocation walls. To leading order, we find that the dislocation wall density is governed by a simple differential equation and that boundary layers are present at both ends of the pile-up. © 2011 Elsevier B.V.

  10. Asymptotic analysis of a pile-up of regular edge dislocation walls

    KAUST Repository

    Hall, Cameron L.

    2011-01-01

    The idealised problem of a pile-up of regular dislocation walls (that is, of planes each containing an infinite number of parallel, identical and equally spaced dislocations) was presented by Roy et al. [A. Roy, R.H.J. Peerlings, M.G.D. Geers, Y. Kasyanyuk, Materials Science and Engineering A 486 (2008) 653-661] as a prototype for understanding the importance of discrete dislocation interactions in dislocation-based plasticity models. They noted that analytic solutions for the dislocation wall density are available for a pile-up of regular screw dislocation walls, but that numerical methods seem to be necessary for investigating regular edge dislocation walls. In this paper, we use the techniques of discrete-to-continuum asymptotic analysis to obtain a detailed description of a pile-up of regular edge dislocation walls. To leading order, we find that the dislocation wall density is governed by a simple differential equation and that boundary layers are present at both ends of the pile-up. © 2011 Elsevier B.V.

  11. Positron-trapping mechanism at dislocations in Zn

    DEFF Research Database (Denmark)

    Hidalgo, Carlos; Linderoth, Søren; Diego, Nieves de

    1987-01-01

    the average lifetime and the intensity of the long component decrease with increasing temperature. The experimental results are very well described in terms of a generalized trapping model where it is assumed that positrons become trapped in deep traps (jogs) via shallow traps (dislocation lines......). The temperature dependence of the positron-lifetime spectra below 120 K is attributed to the temperature dependence of the trapping rate to the dislocation line. The experimental results have demonstrated that detrapping processes from the dislocation line take place above 120 K. The positron binding energy...

  12. Core structure, dislocation energy and Peierls stress for 1/3112-bar 0 edge dislocations with (0001) and {11-bar 00} slip planes in α-Zr

    International Nuclear Information System (INIS)

    Voskoboinikov, R.E.; Osetsky, Yu.N.; Bacon, D.J.

    2005-01-01

    Atomic-scale simulations of edge dislocations of the 1/3112-bar 0(0001) and 1/3112-bar 0{11-bar 00} slip systems have been carried out using a Finnis-Sinclair-type interatomic potential for α-zirconium. The distribution of atomic displacements in the dislocation core shows that in this model the edge dislocation in the basal plane dissociates into two Shockley partials whereas the dislocation in the prism plane remains undissociated. The effective core radius and core energy are estimated, and dislocation response to increasing applied shear strain is investigated. The core properties and the critical stress for dislocation glide (Peierls stress) depend sensitively on whether the core extends or not

  13. Facet joint injuries in acute cervical spine trauma : evaluation with CT and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Jeon Ju; Kim, Dong Hyun; Lee, Jeong Hwa; Lee, Keon; Kwon, Hyeok Po; Kwon, Jung Hyeok; Yun, Seong Mun [Dongkang General Hospital, Seoul (Korea, Republic of)

    1999-05-01

    To evaluate injury patterns of facet joints and associated soft tissue injuries in patients with acute traumatic cervical facet joint injuries. From among patients with cervical spine trauma, 27 with facet joint injuries, as seen on CT and MRI, were chosen for this study. CT scans were analyzed with regard to the location of facet joint injury, the presence or absence of facet dislocation or fracture, and other associated fractures. MR images were analyzed with regard to ligament injury, intervertebral disc injury, intervertebral disc herniation, and spinal cord injury. The most common location of facet joint injury was C6-7 level(n=10), followed by C5-6(n=8). Among these 27 patients with facet joint injuries, 12(44%) had bilateral injuries and 15(56%) unilateral injuries. Facet fractures were present in 17 cases(63%) and the fracture of inferior facet was more frequent than superior. Patterns of fracture were vertical, transverse, or comminuted, but vertical fracture was the most common. Various degrees of dislocation were observed in patients with facet fractures. Fractures other than facet included pillar(n=11), lamina(n=6), transverse process(n=14), body(n=13), and spinous process(n=3). On MR images, anterior longitudinal ligament injury was found in 8 patients(30%), posterior longitudinal ligament injury in 4(15%), and interspinous ligament injury in 20(74%). Twelve patients(44%) had spinal cord injuries including edema(n=8) and hemorrhage(n=4). Among patients with disc abnormalities, 11(41%) had intervertebral disc injuries, and traumatic disc herniations were found in nine. Traumatic cervical facet joint injuries were manifested as various patterns and frequently associated with other fractures or soft tissue injuries. Analysis of CT and MR findings of these injury patterns helped formulate a therapeutic plan and determine of prognosis.

  14. Does occupational therapy reduce the need for surgery in carpometacarpal osteoarthritis? Protocol for a randomized controlled trial.

    Science.gov (United States)

    Kjeken, Ingvild; Eide, Ruth Else Mehl; Klokkeide, Åse; Matre, Karin Hoegh; Olsen, Monika; Mowinckel, Petter; Andreassen, Øyvor; Darre, Siri; Nossum, Randi

    2016-11-15

    In the absence of disease-modifying interventions for hand osteoarthritis (OA), occupational therapy (OT) comprising patient education, hand exercises, assistive devices and orthoses are considered as core treatments, whereas surgery are recommended for those with severe carpometacarpal (CMC1) OA. However, even though CMC1 surgery may reduce pain and improve function, the risk of adverse effects is high, and randomized controlled trials comparing surgery with non-surgical interventions are warranted. This multicentre randomized controlled trial aims to address the following questions: Does OT in the period before surgical consultation reduce the need for surgery in CMC1-OA? What are patients' motivation and reasons for wanting CMC1-surgery? Are there differences between departments of rheumatology concerning the degree of CMC1-OA, pain and functional limitations in patients who are referred for surgical consultation for CMC1 surgery? Is the Measure of Activity Performance of the Hand a reliable measure in patients with CMC1-OA? Do patients with CMC1-OA with and without affection of the distal and proximal interphalangeal finger joints differ with regard to symptoms and function? Do the degree of CMC1-OA, symptoms and functional limitations significantly predict improvement after 2 years following OT or CMC1-surgery? Is OT more cost-effective than surgery in the management of CMC1-OA? All persons referred for surgical consultation due to their CMC1-OA at one of three Norwegian departments of rheumatology are invited to participate. Those who agree attend a clinical assessment and report their symptoms, function and motivation for surgery in validated outcome measures, before they are randomly selected to receive OT in the period before surgical consultation (estimated n = 180). The primary outcome will be the number of participants in each group who have received surgical treatment after 2 years. Secondary and tertiary outcomes are pain, function and

  15. Irradiation-induced amorphization in split-dislocation cores

    International Nuclear Information System (INIS)

    Ovid'ko, I.A.; Rejzis, A.B.

    1999-01-01

    The model describing special splitting of lattice and grain-boundary dislocations as one of the micromechanisms of solid-phase amorphization in irradiated crystals is proposed. Calculation of energy characteristics of the process of dislocations special splitting is carried out [ru

  16. Dislocation core structures in Si-doped GaN

    International Nuclear Information System (INIS)

    Rhode, S. L.; Fu, W. Y.; Sahonta, S.-L.; Kappers, M. J.; Humphreys, C. J.; Horton, M. K.; Pennycook, T. J.; Dusane, R. O.; Moram, M. A.

    2015-01-01

    Aberration-corrected scanning transmission electron microscopy was used to investigate the core structures of threading dislocations in plan-view geometry of GaN films with a range of Si-doping levels and dislocation densities ranging between (5 ± 1) × 10 8  and (10 ± 1) × 10 9  cm −2 . All a-type (edge) dislocation core structures in all samples formed 5/7-atom ring core structures, whereas all (a + c)-type (mixed) dislocations formed either double 5/6-atom, dissociated 7/4/8/4/9-atom, or dissociated 7/4/8/4/8/4/9-atom core structures. This shows that Si-doping does not affect threading dislocation core structures in GaN. However, electron beam damage at 300 keV produces 4-atom ring structures for (a + c)-type cores in Si-doped GaN

  17. Dislocation core structures in Si-doped GaN

    Energy Technology Data Exchange (ETDEWEB)

    Rhode, S. L., E-mail: srhode@imperial.ac.uk; Fu, W. Y.; Sahonta, S.-L.; Kappers, M. J.; Humphreys, C. J. [Department of Materials Science and Metallurgy, University of Cambridge, Charles Babbage Road, Cambridge CB3 0FS (United Kingdom); Horton, M. K. [Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Pennycook, T. J. [SuperSTEM, STFC Daresbury Laboratories, Warrington WA4 4AD (United Kingdom); Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Dusane, R. O. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Moram, M. A. [Department of Materials Science and Metallurgy, University of Cambridge, Charles Babbage Road, Cambridge CB3 0FS (United Kingdom); Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom)

    2015-12-14

    Aberration-corrected scanning transmission electron microscopy was used to investigate the core structures of threading dislocations in plan-view geometry of GaN films with a range of Si-doping levels and dislocation densities ranging between (5 ± 1) × 10{sup 8} and (10 ± 1) × 10{sup 9} cm{sup −2}. All a-type (edge) dislocation core structures in all samples formed 5/7-atom ring core structures, whereas all (a + c)-type (mixed) dislocations formed either double 5/6-atom, dissociated 7/4/8/4/9-atom, or dissociated 7/4/8/4/8/4/9-atom core structures. This shows that Si-doping does not affect threading dislocation core structures in GaN. However, electron beam damage at 300 keV produces 4-atom ring structures for (a + c)-type cores in Si-doped GaN.

  18. Dislocation core structures in (0001) InGaN

    Energy Technology Data Exchange (ETDEWEB)

    Rhode, S. L.; Sahonta, S.-L.; Kappers, M. J.; McAleese, C.; Humphreys, C. J. [Department of Materials Science and Metallurgy, University of Cambridge, Charles Babbage Road, Cambridge CB3 0FS (United Kingdom); Horton, M. K. [Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Haigh, S. J. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); SuperSTEM, STFC Daresbury Laboratories, Warrington WA4 4AD (United Kingdom); Pennycook, T. J. [SuperSTEM, STFC Daresbury Laboratories, Warrington WA4 4AD (United Kingdom); Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Dusane, R. O. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai 400076 (India); Moram, M. A. [Department of Materials Science and Metallurgy, University of Cambridge, Charles Babbage Road, Cambridge CB3 0FS (United Kingdom); Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom)

    2016-03-14

    Threading dislocation core structures in c-plane GaN and In{sub x}Ga{sub 1−x}N (0.057 ≤ x ≤ 0.20) films were investigated by aberration-corrected scanning transmission electron microscopy. a-type dislocations are unaffected by alloying with indium and have a 5/7-atom ring core structure in both GaN and In{sub x}Ga{sub 1−x}N. In contrast, the dissociation lengths of (a + c)-type dislocations are reduced, and new 7/4/9-atom ring and 7/4/8/5-atom ring core structures were observed for the dissociated (a + c)-type dislocations in In{sub x}Ga{sub 1−x}N, which is associated with the segregation of indium near (a + c)-type and c-type dislocation cores in In{sub x}Ga{sub 1−x}N, consistent with predictions from atomistic Monte Carlo simulations.

  19. Self-force on dislocation segments in anisotropic crystals

    International Nuclear Information System (INIS)

    Fitzgerald, S P; Aubry, S

    2010-01-01

    A dislocation segment in a crystal experiences a 'self-force', by virtue of the orientation dependence of its elastic energy. If the crystal is elastically isotropic, this force is manifested as a couple acting to rotate the segment toward the lower energy of the pure screw orientation (i.e. acting to align the dislocation line with its Burgers vector). If the crystal is anisotropic, there are additional contributions to the couple, arising from the more complex energy landscape of the lattice itself. These effects can strongly influence the dynamic evolution of dislocation networks, and via their governing role in dislocation multiplication phenomena, control plastic flow in metals. In this paper we develop a model for dislocation self-forces in a general anisotropic crystal, and briefly consider the technologically important example of α-iron, which becomes increasingly anisotropic as the temperature approaches that of the α-γ phase transition at 912 0 C.

  20. Interaction energy of interface dislocation loops in piezoelectric bi-crystals

    Directory of Open Access Journals (Sweden)

    Jianghong Yuan

    2017-03-01

    Full Text Available Interface dislocations may dramatically change the electric properties, such as polarization, of the piezoelectric crystals. In this paper, we study the linear interactions of two interface dislocation loops with arbitrary shape in generally anisotropic piezoelectric bi-crystals. A simple formula for calculating the interaction energy of the interface dislocation loops is derived and given by a double line integral along two closed dislocation curves. Particularly, interactions between two straight segments of the interface dislocations are solved analytically, which can be applied to approximate any curved loop so that an analytical solution can be also achieved. Numerical results show the influence of the bi-crystal interface as well as the material orientation on the interaction of interface dislocation loops.

  1. Atomistically determined phase-field modeling of dislocation dissociation, stacking fault formation, dislocation slip, and reactions in fcc systems

    Science.gov (United States)

    Rezaei Mianroodi, Jaber; Svendsen, Bob

    2015-04-01

    The purpose of the current work is the development of a phase field model for dislocation dissociation, slip and stacking fault formation in single crystals amenable to determination via atomistic or ab initio methods in the spirit of computational material design. The current approach is based in particular on periodic microelasticity (Wang and Jin, 2001; Bulatov and Cai, 2006; Wang and Li, 2010) to model the strongly non-local elastic interaction of dislocation lines via their (residual) strain fields. These strain fields depend in turn on phase fields which are used to parameterize the energy stored in dislocation lines and stacking faults. This energy storage is modeled here with the help of the "interface" energy concept and model of Cahn and Hilliard (1958) (see also Allen and Cahn, 1979; Wang and Li, 2010). In particular, the "homogeneous" part of this energy is related to the "rigid" (i.e., purely translational) part of the displacement of atoms across the slip plane, while the "gradient" part accounts for energy storage in those regions near the slip plane where atomic displacements deviate from being rigid, e.g., in the dislocation core. Via the attendant global energy scaling, the interface energy model facilitates an atomistic determination of the entire phase field energy as an optimal approximation of the (exact) atomistic energy; no adjustable parameters remain. For simplicity, an interatomic potential and molecular statics are employed for this purpose here; alternatively, ab initio (i.e., DFT-based) methods can be used. To illustrate the current approach, it is applied to determine the phase field free energy for fcc aluminum and copper. The identified models are then applied to modeling of dislocation dissociation, stacking fault formation, glide and dislocation reactions in these materials. As well, the tensile loading of a dislocation loop is considered. In the process, the current thermodynamic picture is compared with the classical mechanical

  2. Fabrication of mesoscopic floating Si wires by introducing dislocations

    International Nuclear Information System (INIS)

    Motohashi, Mitsuya; Shimizu, Kazuya; Niwa, Masaaki; Suzuki, Toshiaki

    2014-01-01

    We fabricated a mesoscopic Si wire by introducing dislocations in a silicon wafer before HF anodization. The dislocations formed along the (111) crystal plane. The outline of the dislocation line was an inverted triangle. The resulting wire floated on a bridge girder and had a hybrid structure consisting of a porous layer and crystalline Si. The cross section of the wire had an inverted triangle shape. The wire formation mechanism is discussed in terms of carrier transport, crystal structure, and dislocation formation during anodization. (paper)

  3. Fabrication of mesoscopic floating Si wires by introducing dislocations

    Science.gov (United States)

    Motohashi, Mitsuya; Shimizu, Kazuya; Suzuki, Toshiaki; Niwa, Masaaki

    2014-12-01

    We fabricated a mesoscopic Si wire by introducing dislocations in a silicon wafer before HF anodization. The dislocations formed along the (111) crystal plane. The outline of the dislocation line was an inverted triangle. The resulting wire floated on a bridge girder and had a hybrid structure consisting of a porous layer and crystalline Si. The cross section of the wire had an inverted triangle shape. The wire formation mechanism is discussed in terms of carrier transport, crystal structure, and dislocation formation during anodization.

  4. Scattering of phonons by dislocations

    International Nuclear Information System (INIS)

    Anderson, A.C.

    1979-01-01

    By 1950, an explicit effort had been launched to use lattice thermal conductivity measurements in the investigation of defect structures in solids. This technique has been highly successful, especially when combined with the measurements of other properties such as optical absorption. One exception has been the study of dislocations. Although dislocations have a profound effect on the phonon thermal conductivity, the mechanisms of the phonon-dislocation interaction are poorly understood. The most basic questions are still debated in the literature. It therefore is pointless to attempt a quantitative comparison between an extensive accumulation of experimental data on the one hand, and the numerous theoretical models on the other. Instead, this chapter will attempt to glean a few qualitative conclusions from the existing experimental data. These results will then be compared with two general models which incorporate, in a qualitative manner, most of the proposed theories of the phonon-dislocation interaction. Until very recently, measurement of thermal conductivity was the only means available to probe the interaction between phonons and defects at phonon frequencies above the standard ultrasonic range of approx. = 10 9 Hz. The introductory paragraphs provide a brief review of the thermal-conductivity technique and the problems which are encountered in practice. There is also a brief presentation of the theoretical models and the complications that may occur in more realistic situations

  5. Interaction of helium atoms with edge dislocations in α-Fe

    International Nuclear Information System (INIS)

    Heinisch, H.L.; Gao, F.; Kurtz, R.J.; Le, E.A.

    2006-01-01

    Formation energies, binding energies, and migration energies of interstitial He atoms in and near the core of an a/2 {1 1 0} edge dislocation in α-Fe are determined in atomistic simulations using conjugate gradient relaxation and the Dimer method for determining saddle point energies. Results are compared as a function of the proximity of the He to the dislocation core and the excess interstitial volume in regions around the dislocation. Interstitial He atoms have negative binding energy on the compression side of the dislocation and strong positive binding energy on the tension side. Even at low temperatures, interstitial He atoms in the vicinity of the dislocation easily migrate to the dislocation core, where they form crowdion interstitials oriented along the close-packed slip direction, with binding energies in excess of 2 eV. Crowdion interstitial He atoms diffuse along the dislocation core, transverse to the crowdion direction, with a migration energy of 0.4-0.5 eV

  6. The hematoma block: a simple, effective technique for closed reduction of ankle fracture dislocations.

    Science.gov (United States)

    Ross, Adrianne; Catanzariti, Alan R; Mendicino, Robert W

    2011-01-01

    Management of a dislocated ankle fracture can be challenging because of instability of the ankle mortise, a compromised soft tissue envelope, and the potential neurovascular compromise. Every effort should be made to quickly and efficiently relocate the disrupted ankle joint. Within the emergency department setting, narcotics and benzodiazepines can be used to sedate the patient before attempting closed reduction. The combination of narcotics and benzodiazepines provides relief of pain and muscle guarding; however, it conveys a risk of seizure as well as respiratory arrest. An alternative to conscious sedation is the hematoma block, or an intra-articular local anesthetic injection in the ankle joint and the associated fracture hematoma. The hematoma block offers a comparable amount of analgesia to conscious sedation without the additional cardiovascular risk, hospital cost, and procedure time. Copyright © 2011 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Edge dislocations in dicalcium silicates: Experimental observations and atomistic analysis

    International Nuclear Information System (INIS)

    Shahsavari, Rouzbeh; Chen, Lu; Tao, Lei

    2016-01-01

    Understanding defects and influence of dislocations on dicalcium silicates (Ca 2 SiO 4 ) is a challenge in cement science. We report a high-resolution transmission electron microscopy image of edge dislocations in Ca 2 SiO 4 , followed by developing a deep atomic understanding of the edge dislocation-mediated properties of five Ca 2 SiO 4 polymorphs. By decoding the interplay between core dislocation energies, core structures, and nucleation rate of reactivity, we find that γ-C2S and α-C2S polymorphs are the most favorable polymorphs for dislocations in Ca 2 SiO 4 , mainly due to their large pore channels which take away majority of the distortions imposed by edge dislocations. Furthermore, in the context of edge dislocation, while α-C2S represents the most active polymorph for reactivity and crystal growth, β-C2S represents the most brittle polymorph suitable for grinding. This work is the first report on the atomistic-scale analysis of edge dislocation-mediated properties of Ca 2 SiO 4 and may open up new opportunities for tuning fracture and reactivity processes of Ca 2 SiO 4 and other cement components.

  8. Dislocation of primary total hip arthroplasty and the risk of redislocation.

    LENUS (Irish Health Repository)

    Brennan, Stephen A

    2012-09-01

    6554 primary total hip arthroplasties were reviewed. Risk factors for dislocation were analysed to assess which were important in terms of predicting recurrent instability. The patients risk of having a second dislocation was independently associated with the surgical approach adopted (p = 0.03) and the time to first dislocation from the primary hip replacement (p = 0.002). Early dislocators whose surgery was performed through an anterolateral approach had less recurrence than late dislocators through a posterior or transtrochanteric approach. None of the other risk factors including head size (p = 0.59), modularity (p = 0.54), mechanism of dislocation (p = 0.23), leg length discrepancy (p = 0.69) and acetabular inclination (p = 0.31) were influential. The use of an abduction brace was not useful in preventing a further dislocation with 69.2% of those braced re-dislocating compared to 68.5% who were not braced (p = 0.96).

  9. [Double Endobutto reconstituting coracoclavicular ligament combined with repairing acromioclavicular ligament at stage I for the treatment of acromioclavicular dislocation with Rockwood type III - V].

    Science.gov (United States)

    Hu, Wen-yue; Yu, Chong; Huang, Zhong-ming; Han, Lei

    2015-06-01

    To explore clinical efficacy of double Endobutto reconstituting coracoclavicular ligament combined with repairing acromioclavicular ligament in stage I in treating acromioclavicular dislocation with Rockwood type III - V . From January 2010 to September 2013, 56 patients with Rockwood type III - V acromioclavicular dislocation were treated by operation, including 20 males and 36 femlaes, aged from 32 to 52 years old with an average of 38.5 years old. Twenty-five patients were on the left side and 31 cases on the right side. The time from injury to operation was from 3 to 14 days, averaged 7 days. All patients were diagnosed as acromioclavicular dislocation with Rockwood type III - V, and double Endobutto were used to reconstituting coracoclavicular ligament, line metal anchors were applied for repairing acromioclavicular ligament. Postoperative complications were observed, Karlsson and Constant-Murley evaluation standard were used to evaluate clinical effects. All patients were followed up from 8 to 24 months with average of 11 months. According to Karlsson evaluation standard at 6 months after operation,42 cases were grade A, 13 were grade B and 1 was grade C. Constant-Murley score were improved from (42.80±5.43) before operation to (91.75±4.27) at 6 months after operation. All items at 6 months after operation were better than that of preoperative items. Forty-eight patients got excellent results, 7 were moderate and only 1 with bad result. No shoulder joint adhesion, screw loosening or breakage were occurred during following up. Double Endobutto reconstituting coracoclavicular ligament combined with repairing acromioclavicular ligament in stage I for the treatment of acromioclavicular dislocation with Rockwood type III - V could obtain early staisfied clinical effects, and benefit for early recovery of shoulder joint function.

  10. Interstitial impurity interactions and dislocation microdynamics in Mo crystals

    International Nuclear Information System (INIS)

    Kwok, D.N.

    1975-05-01

    The effects of interstitial impurities on the mechanical properties of molybdenum are explored by comparing results obtained for crystals of various interstitial contents controlled by ultra-high vacuum outgassing. Results show a modulus reduction for as-grown samples and for outgassed specimens at low applied stresses. As a function of plastic microstrain, the values of modulus defect for both as-grown and outgassed specimens saturate at the same value. Interstitial impurities act as pinning agents to dislocation bowing, but when all the easy dislocation loops have broken away from local interstitial pins, the modulus defect reaches a constant saturation value. Etch pitting techniques were used to correlate microstrain observations with dislocation generation and motion. It has been found that edge dislocation generation and movement are active in the microstrain region while screw dislocations are relatively inactive until the macrostrain region is reached. Dislocation velocities range from 10 -6 to 10 -3 cm/s and the average distance between interstitial impurity pinning points is found to be approximately 8 x 10 -4 cm. (U.S.)

  11. On damping of screw dislocation bending vibrations in dissipative crystal: limiting cases

    Science.gov (United States)

    Dezhin, V. V.

    2018-03-01

    The expression for the generalized susceptibility of the dislocation obtained earlier was used. The electronic drag mechanism of dislocations is considered. The study of small dislocation oscillations was limited. The contribution of the attenuation of low-frequency bending screw dislocation vibrations to the overall coefficient of dynamic dislocation drag in the long-wave and short-wave limits is calculated. The damping of short-wave bending screw dislocation vibrations caused by an external action of an arbitrary frequency has been investigated. The contribution of long-wave bending screw dislocation vibrations damping in the total drag coefficient at an arbitrary frequency is found.

  12. Bilateral Posterior Tibial Tendon and Flexor Digitorum Longus Dislocations.

    Science.gov (United States)

    Padegimas, Eric M; Beck, David M; Pedowitz, David I

    2017-04-01

    The authors present a case of a previously healthy and athletic 17-year-old female who presented with a 3.5-year history of medial left ankle pain after sustaining an inversion injury while playing basketball. Prior to presentation, she had failed prior immobilization and physical therapy for a presumed ankles sprain. Physical examination revealed a dislocated posterior tibial tendon (PTT) that was temporarily reducible, but would spontaneously dislocate immediately after reduction. She had pain and snapping of the PTT with resisted ankle plantar flexion and resisted inversion as well as 4/5 strength in ankle inversion. The diagnosis of dislocated PTT was confirmed on magnetic resonance imaging (MRI). The patient underwent suture anchor repair of the medial retinaculum of the left ankle. At the time of surgery both the PTT and flexor digitorum longus (FDL) were dislocated. Three months postoperatively, the patient represented with PTT dislocation of the right (nonoperative) ankle confirmed by MRI. After failure of immobilization, physical therapy, and oral anti-inflammatory medications, the patient underwent suture anchor repair of the medial retinaculum of the right ankle. At 6 months postoperatively, the patient has 5/5 strength inversion bilaterally, no subluxation of either PTT, and has returned to all activities without limitation. The authors present this unique case of bilateral PTT dislocation and concurrent PTT/FDL dislocation along with review of the literature for PTT dislocation. The authors highlight the common misdaiganosis of this injury and highlight the successful results of surgical intervention. Level V: Case report.

  13. Energetics of dislocation transformations in hcp metals

    International Nuclear Information System (INIS)

    Wu, Zhaoxuan; Yin, Binglun; Curtin, W.A.

    2016-01-01

    Dislocation core structures of hcp metals are highly complex and differ significantly among the hcp family. Some dislocations undergo unconventional transformations that have significant effects on the material plastic flow. Here, the energetics of dislocation dissociations are analyzed in a general anisotropic linear elastic theory framework for transformations in which changes in the partial Burgers vectors are small. Quantitative analyses on various transformations are made using DFT-computed stacking fault energies and partial Burgers vectors. Specifically, possible transformations of the mixed, edge, and screw 〈c+a〉 and screw 〈a〉 dislocations in 6 hcp metals (Mg, Ti, Zr, Re, Zn, Cd) are studied. Climb dissociation of mixed or edge 〈c+a〉 dislocations to the Basal plane is energetically favorable in all 6 metals and thus only limited by thermal activation. The 〈c+a〉 screw dislocation is energetically preferable on Pyramidal I for Ti, Zr, and Re, and on Pyramidal II for Zn and Cd. In Mg, the energy difference between screw 〈c+a〉 on Pyramidal I and II planes is small, suggesting relatively easy cross-slip. For the screw 〈a〉, Basal dissociation is energetically favorable in Mg, Re, Zn and Cd, while Prism dissociation is strongly favorable in Ti and Zr. Only Ti, Zr and Re show a metastable state for dissociation on the Prism plane, and the energy difference between screw 〈a〉 on the Prism and Pyramidal I planes is relatively small in all systems, suggesting relatively easy cross-slip of 〈a〉 in Ti and Zr. The elastic analysis thus provides a single framework able to capture the controlling energetics for different dissociations and slip systems in hcp metals. When the calculated energy differences are very small, the results point to the need for detailed modeling of the atomistic core structure. Moreover, the analyses rationalize broad experimental observations on dominant slip systems and dislocation behaviours, and provide

  14. A parallel algorithm for 3D dislocation dynamics

    International Nuclear Information System (INIS)

    Wang Zhiqiang; Ghoniem, Nasr; Swaminarayan, Sriram; LeSar, Richard

    2006-01-01

    Dislocation dynamics (DD), a discrete dynamic simulation method in which dislocations are the fundamental entities, is a powerful tool for investigation of plasticity, deformation and fracture of materials at the micron length scale. However, severe computational difficulties arising from complex, long-range interactions between these curvilinear line defects limit the application of DD in the study of large-scale plastic deformation. We present here the development of a parallel algorithm for accelerated computer simulations of DD. By representing dislocations as a 3D set of dislocation particles, we show here that the problem of an interacting ensemble of dislocations can be converted to a problem of a particle ensemble, interacting with a long-range force field. A grid using binary space partitioning is constructed to keep track of node connectivity across domains. We demonstrate the computational efficiency of the parallel micro-plasticity code and discuss how O(N) methods map naturally onto the parallel data structure. Finally, we present results from applications of the parallel code to deformation in single crystal fcc metals

  15. Sports activity after anatomic acromioclavicular joint stabilisation with flip-button technique.

    Science.gov (United States)

    Porschke, Felix; Schnetzke, Marc; Aytac, Sara; Studier-Fischer, Stefan; Gruetzner, Paul Alfred; Guehring, Thorsten

    2017-07-01

    Sports activity after surgical AC joint stabilisation has not been comprehensively evaluated to date. The aim of this study was to determine rate, level and time to return to sports after AC joint stabilisation and to identify the influence of overhead sports on post-operative sports activity. In this retrospective case series, a total of 68 patients with a high-grade AC joint dislocation (Rockwood type V) were stabilised using a single TightRope technique. Fifty-five patients (80.9 %) with median age of 42.0 (range, 18-65) years completed questionnaires regarding sports activity before and after surgery. Clinical outcome and complications were also evaluated. Forty-three patients participated in sports regularly before injury. Their sports activity was rated according to Allain, and non-overhead and overhead sports were differentiated. At median follow-up of 24 (18-45) months, 41 of 43 patients (95.3 %) had returned to sports. 63 % returned to the same sports activity as before injury. 16.3 % needed to adapt the type of sports to reduce demanding activities. 11.6 % reduced the frequency and 32.5 % the intensity of sports. The median time to return to sports was 9.5 (3-18) months. Overhead athletes (Allain Type III and IV) had to reduce their sports activity significantly more often (11.8 vs. 53.8 %; p = 0.011) and needed more time to return to sports (9.5 vs. 4.5 months; p = 0.009). After stabilisation of AC joint dislocation, the majority of patients returned to sports after a substantial period of time. Overhead athletes, in particular, required more time and had to considerably reduce their sports activity. The findings impact therapeutic decision-making after AC joint injury and help with the prognosis and assessment of rehabilitation progress. IV.

  16. Effect of dislocations on superconductivity. O vliyanii dislokatsiy na sverkhrpovodimost'

    Energy Technology Data Exchange (ETDEWEB)

    Agap' ev, B D; Bytsenko, A A; Sukhanov, S A

    1976-01-01

    Electron-dislocation interaction is analyzed here. The effect of dislocations on the superconductor characteristics is determined according to the Ginzburg-Landau method. Appreciable changes in the stability of the superconductive state are found to occur in the vicinity of dislocations.

  17. A three dimensional discrete dislocation dynamics modelling of the early cycles of fatigue in an austenitic stainless steel 316L: dislocation microstructure and damage analysis

    International Nuclear Information System (INIS)

    Depres, Ch.

    2005-01-01

    A numerical code modelling the collective behaviour of dislocations at a mesoscopic scale (Discrete Dislocation Dynamics code) is used to analyse the cyclic plasticity that occurs in surface grains of an AISI 316L stainless steel, in order to understand the plastic mechanism involved in crack initiation in fatigue. Firstly, the analyses of both the formation and the evolution of the dislocation microstructures show the crucial role of cross-slip played in the strain localization in the form of slip bands. As the cycling proceeds, the slip bands exhibit well-organized dislocation arrangements that substitute to dislocation tangles, involving specific interaction mechanisms between primary and deviate systems. Secondly, both the surface displacements generated by plastic slip and the distortion energy induced by the dislocation microstructure have been analysed. We find that an irreversible surface relief in the form of extrusion/intrusion can be induced by cyclic slip of dislocations. The number of cycles for the crack initiation follows a Manson-Coffin type law. The analyses of the concentration of the distortion energy and its repartition in the slip bands show that beneficial energetic zones may be present at the very beginning of the cycling, and that mode-II crack propagation in the surface grains results from a succession of micro-crack initiations along primary slip plane, which is facilitated by various effects (stress concentration due to surface relief, environment effects...). Finally, a dislocation-based model for cyclic plasticity is proposed from Discrete Dislocation Dynamics results. (author)

  18. Dislocation dynamics modelling of radiation damage in thin films

    International Nuclear Information System (INIS)

    Ferroni, Francesco; Tarleton, Edmund; Fitzgerald, Steven

    2014-01-01

    Transmission electron microscopy is a key tool for the extraction of information on radiation damage, the understanding of which is critical for materials development for nuclear fusion and fission reactors. Dislocations in TEM samples are subject to strong image forces, owing to the nanometric sample thicknesses, which may introduce artifacts in the damage analysis. Using dislocation dynamics, we elucidate the roles played by dislocation–surface interactions, dislocation–dislocation interactions and self-interactions due to climb for loop types observed in TEM. Comparisons with analytic solutions for a dislocation loop and an edge dislocation in a half-space are included, and the relationship between glide force and loop tilt examined. The parameters for convergence of the zero-traction boundary conditions are obtained, after which the evolution of dislocation structures in a thin film is studied. It is found that three main length scales govern the physical processes: the image force is governed by the distance of the loop from the surface and scales with the film thickness; the glide force is governed by the image stress as well as the loop–loop interaction stress which is in turn governed by the loop spacing L∼1/√ρ, where ρ is the loop density; finally, the climb force depends on the loop size. The three forces compete and their relative magnitudes define the evolution pathway of the dislocation structure. (paper)

  19. Discuss the cause and treatment of pacemaker lead dislocation and deal with

    International Nuclear Information System (INIS)

    Chen Yueguang; Zhang Dadong; Lu Jie; Yang Hui; Liu Chunyan; Zhang Wei

    2003-01-01

    Objective: To follow up the patients with pacemaker, observe the condition of pacemaker lead, to explore the cause of lead dislocation, to find out and prevent its occurrence. Methods: Summarizing the clinical data of 6 patients with pacemaker, 7 pacemaker leads with 8 time dislocation, pacemaker 2 DDDR, 2 DDD, 2 VVI. Results: Four patients were punctured from right subclavian vein, one from left subclavian vein and one from right brachiocephalic vein; four leads were dislocation in atrium and one mildly dislocation; four leads dislocation in ventricle and two mildly dislocation; There were 3 old women with 4 leads and 5 times of dislocation

  20. Prolotherapy: A new hope for temporomandibular joint pain

    Directory of Open Access Journals (Sweden)

    A Vijay Kumar

    2013-01-01

    Full Text Available The most common cause of orofacial pain is the Temporomandibular Joint Disorder (TMD, a collective term used to describe a group of medical disorders causing temporomandibular joint (TMJ pain and dysfunction. As the causes of TMD are varied and run the gamut from mechanical issues, such as disc degeneration and dislocation or erosion of the fibrocartilaginous surfaces of the condyle, fossa, and articular eminence, the treatment approaches for the chronic TMJ case are also quite varied. As surgery is considered a last resort for TMD, it is common for sufferers to seek out alternatives and one of the alternative treatments is ′Prolotherapy,′ which is also known as Regenerative Injection Therapy. This article provides an overview of this new alternative therapy.

  1. Dislocations and radiation damage in {alpha}-uranium; Dislocations et effets des radiations dans l'uranium {alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Leteurtre, J [Commissariat a l' Energie Atomique, 92 - Fontenay-Aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    Dislocations in {alpha}-uranium were studied by electron microscopy. Electropolishing of thin foils was performed at low temperature (-110 deg. C) to prevent oxidation. Burgers vectors of twins dislocations are defined. Interactions between slip and twinning are studied from both experimental and theoretical point of view. Samples irradiated at several burn-up were examined. In order to explain our micrographic results, and also all information gathered in literature about radiation damage in {alpha}-uranium, a coherent model is propound for the fission particles effects. We analyse the influences of parameters: temperature, dislocation density, impurity content. The number of point defects created by one initial fission is determined for pure and annealed metal. The importance of the self-anneal which occurs immediately in each displacement spike, and the anneal due to a new fission on the damage resulting from a previous fission, are estimated. The focussing distance in [100] direction is found to be about 1000 Angstrom, at 4 deg. K. (author) [French] Ce travail est une etude par microscopie electronique des dislocations induites dans l'uranium {alpha}, soit par deformation plastique, soit par irradiation. Une methode de preparation des lames minces a basse temperature (-110 deg. C) a ete mise au point. Les vecteurs de Burgers des diverses dislocations de macles de ce metal ont ete definis. Les interactions glissements- maclages sont etudiees experimentalement et theoriquement. Des echantillons irradies a divers taux de combustion ont ete examines. Pour expliquer nos resultats micrographiques, et aussi l'ensemble des informations recueillies dans la litterature concernant l'endommagement par irradiation de l'uranium-{alpha}, nous proposons un modele coherent de l'effet des fragments de fission dans ce metal. L'influence des parametres: temperature, densite de dislocations, impuretes est analysee. Le nombre de defauts ponctuels crees par une fission dans du metal

  2. Growth and instability of charged dislocation loops under irradiation in ceramic materials

    CERN Document Server

    Ryazanov, A I; Kinoshita, C; Klaptsov, A V

    2002-01-01

    We have investigated the physical mechanisms of the growth and stability of charged dislocation loops in ceramic materials with very strong different mass of atoms (stabilized cubic zirconia) under different energies and types of irradiation conditions: 100-1000 keV electrons, 100 keV He sup + and 300 keV O sup + ions. The anomalous formation of extended defect clusters (charged dislocation loops) has been observed by TEM under electron irradiation subsequent to ion irradiation. It is demonstrated that very strong strain field (contrast) near charged dislocation loops is formed. The dislocation loops grow up to a critical size and after then become unstable. The instability of the charged dislocation loop leads to the multiplication of dislocation loops and the formation of dislocation network near the charged dislocation loops. A theoretical model is suggested for the explanation of the growth and stability of the charged dislocation loop, taking the charge state of point defects. The calculated distribution...

  3. Hip dysplasia and congenital hip dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Lingg, G.; Nebel, G.; von Torklus, D.

    1981-11-01

    In human genetics and orthopedics quite different answers have been given to the question of hereditary transmission and frequency of hip dysplasia in families of children with congenital hip dislocation. We therefore have made roentgenometric measurements of 110 parents of children with congenital hip dislocation. In 25% we found abnormal flat acetabulae, whereas 12% had pathologic deep hips. This may propose a new concept of morphology of congenital hip dysplasia.

  4. Surgical dislocation of the hip in patients with femoroacetabular impingement: Surgical techniques and our experience

    Directory of Open Access Journals (Sweden)

    Mladenović Marko

    2015-01-01

    Full Text Available Background/Aim. Arthrosis of the hip is the most common cause of a hip joint disorders. The aim of this study was to present our experience in the application of a safe surgical dislocation of the hip in patients with minor morphological changes in the hip joint, which, through the mechanism of femoroacetabular impingement, cause damage to the acetabular labrum and adjacent cartilage as an early sign of the hip arthrosis. Methods. We have operated 51 patients with different morphological bone changes in the hip area and resultant soft tissue damage of the acetabular labrum and its adjacent cartilage. Surgical technique that we applied in this group of patients, was adapted to our needs and capabilities and it was minimaly modified compared to the original procedure. Results. The surgical technique presented in this paper, proved to be a good method of treatment of bone and soft tissue pathomorphological changes of the hip in patients with femoroacetabular impingement. We had no cases with avascular necrosis of the femoral head, and two patients had nonunion of the greater trochanter, 9 patients developed paraarticular ossification, without subjective symptoms, while 3 patients suffered from postoperative pain in the groin during more energetic physical activities. Conclusion. Utilization of our partly modified surgical technique of controlled and safe dislocation of the hip can solve all the bone and soft tissue problems in patients with femoroacetibular impingement to stop already developed osteoarthritis of the hip or to prevent mild form of it.

  5. Dislocations in AlGaN: Core Structure, Atom Segregation, and Optical Properties.

    Science.gov (United States)

    Massabuau, Fabien C-P; Rhode, Sneha L; Horton, Matthew K; O'Hanlon, Thomas J; Kovács, András; Zielinski, Marcin S; Kappers, Menno J; Dunin-Borkowski, Rafal E; Humphreys, Colin J; Oliver, Rachel A

    2017-08-09

    We conducted a comprehensive investigation of dislocations in Al 0.46 Ga 0.54 N. Using aberration-corrected scanning transmission electron microscopy and energy dispersive X-ray spectroscopy, the atomic structure and atom distribution at the dislocation core have been examined. We report that the core configuration of dislocations in AlGaN is consistent with that of other materials in the III-Nitride system. However, we observed that the dissociation of mixed-type dislocations is impeded by alloying GaN with AlN, which is confirmed by our experimental observation of Ga and Al atom segregation in the tensile and compressive parts of the dislocations, respectively. Investigation of the optical properties of the dislocations shows that the atom segregation at dislocations has no significant effect on the intensity recorded by cathodoluminescence in the vicinity of the dislocations. These results are in contrast with the case of dislocations in In 0.09 Ga 0.91 N where segregation of In and Ga atoms also occurs but results in carrier localization limiting non-radiative recombination at the dislocation. This study therefore sheds light on why InGaN-based devices are generally more resilient to dislocations than their AlGaN-based counterparts.

  6. Is coracoclavicular stabilisation alone sufficient for the endoscopic treatment of severe acromioclavicular joint dislocation (Rockwood types III, IV, and V)?

    Science.gov (United States)

    Barth, J; Duparc, F; Andrieu, K; Duport, M; Toussaint, B; Bertiaux, S; Clavert, P; Gastaud, O; Brassart, N; Beaudouin, E; De Mourgues, P; Berne, D; Bahurel, J; Najihi, N; Boyer, P; Faivre, B; Meyer, A; Nourissat, G; Poulain, S; Bruchou, F; Ménard, J F

    2015-12-01

    The primary objective was to evaluate correlations linking anatomical to functional outcomes after endoscopically assisted repair of acute acromioclavicular joint dislocation (ACJD). Combined acromioclavicular and coracoclavicular stabilisation improves radiological outcomes compared to coracoclavicular stabilisation alone. A prospective multicentre study was performed. Clinical outcome measures were pain intensity on a visual analogue scale (VAS), subjective functional impairment (QuickDASH score), and Constant's score. Anatomical outcomes were assessed on standard radiographs (anteroposterior view of the acromioclavicular girdle and bilateral axillary views) obtained preoperatively and postoperatively and on postoperative dynamic radiographs taken as described by Tauber et al. Of 116 patients with acute ACJD included in the study, 48% had type III, 30% type IV, and 22% type V ACJD according to the Rockwood classification. Coracoclavicular stabilisation was achieved using a double endobutton in 93% of patients, and concomitant acromioclavicular stabilisation was performed in 50% of patients. The objective functional outcome was good, with an unweighted Constant's score ≥ 85/100 and a subjective QuickDASH functional disability score ≤ 10 in 75% of patients. The radiographic analysis showed significant improvements from the preoperative to the 1-year postoperative values in the vertical plane (decrease in the coracoclavicular ratio from 214 to 128%, p=10(-6)) and in the horizontal plane (decrease in posterior displacement from 4 to 0mm, p=5×10(-5)). The anatomical outcome correlated significantly with the functional outcome (absolute R value=0.19 and p=0.045). We found no statistically significant differences across the various types of constructs used. Intra-operative control of the acromioclavicular joint did not improve the result. Implantation of a biological graft significantly improved both the anatomical outcome in the vertical plane (p=0.04) and

  7. Epidemiological Profile of Extremity Fractures and Dislocations in Road Traffic Accidents in Kashan, Iran:a Glance at the Related Disabilities

    Directory of Open Access Journals (Sweden)

    Mehrdad Mahdian

    2017-05-01

    Full Text Available Background: Apart from the mortality, road traffic injuries are associated with significant morbidities. This study has aimed to examine the pattern of traffic accident-related extremity fractures/dislocations and their related disabilities. Methods: A retrospective hospital-based study was conducted to assess the characteristics of limb fractures/dislocations among road traffic accident victims registered in Trauma Research Center registry of Kashan University of Medical Sciences, Kashan, Iran, during 2012-2013. Age and sex distribution, cause of injury, and site of fractures/dislocations were recorded. Years lived with disability (YLD was calculated as a scale to measure the disability. One-way ANOVA and chi-square tests were used for data analysis. Results: From a total of 962 subjects, 812 (84.4% were males (the male/female sex ratio: 5.4:1. The mean age of victims was 32.7±17.9. Leg (37% and forearm (19% fractures were the most frequent fractures. Shoulder dislocations were among the most affected joints accounting for 36.6% of the cases. The total calculated YLD was 135.6 (34.4 for temporal and 101.2 for lifelong disabilities, and totally 117.3 and 18.3 for males and females, respectively. The highest YLD was for motorcyclists (104 and while the most YLD was for 15-29 years (68.2. Conclusion: Young men motorcyclist accidents are a major problem in Kashan region. Generally, they have been accounted for the highest YLD due to fractures/dislocations, especially in lower extremity. Although the calculated YLD will be decreased with increasing age, the elder people also had the high rate of traffic-related limb injuries.

  8. Transmission electron microscopy in situ investigation of dislocation mobility in semiconductors

    CERN Document Server

    Vanderschaeve, G; Insa, P D T; Caillard, D

    2000-01-01

    TEM in situ straining experiments provide a unique way to investigate in real time the behaviour of individual dislocations under applied stress. The results obtained on a variety of semiconductors are presented: numerous dislocation sources are observed which makes it possible to measure the dislocation velocity as a function of different physical parameters (local shear stress, temperature, dislocation character, length of the moving dislocation, ...). The experimental results are consistent with a dislocation glide governed by the Peierls mechanism, even for II-VI compounds which have a significant degree of ionic character. For compounds, a linear dependence of the dislocation velocity on the length of the moving segment is noticed, whereas for elemental semiconductors a transition between a length-dependent and a length-independent velocity regime is observed. Analysed in the framework of the kink diffusion model (Hirth and Lothe theory), these results allow an estimation of the kink formation and migrat...

  9. Dislocation kinetics and the acoustic-wave approximation for liquids

    International Nuclear Information System (INIS)

    Stout, R.B.

    1983-03-01

    A dislocation-dependent model for liquids describes the lattice deformation and the fluidity deformation as additive deformations. The lattice deformation represents distortions of an atom's potential energy structure and is a recoverable deformation response. The fluidity deformation represents discontinuous repositioning of atoms by dislocation kinetics in the lattice structure and is a nonrecoverable deformation response. From this model, one concludes that in liquids the acoustic-wave approximation is a description of a recoverable oscillation deformation that has dissipation because of dislocation kinetics. Other more-complex waves may exist, but such waves would rapidly disappear because of the small thermodynamic potential for dislocation kinetics in liquids

  10. High-voltage electron-microscopical observation of crack-tip dislocations in silicon crystals

    International Nuclear Information System (INIS)

    Tanaka, Masaki; Higashida, Kenji

    2005-01-01

    Crack-tip dislocations in silicon single crystals were observed by high-voltage electron microscopy. Cracks were introduced into silicon wafers at room temperature by a Vickers indenter. The indented specimens were annealed at 823 K in order to activate dislocation emission from the crack tip under the residual stress due to the indentation. In the specimen without annealing, no dislocations were observed around the crack. On the other hand, in the specimen after the annealing, the aspect of the early stage of dislocation emission was observed, where dislocations were emitted not as a perfect dislocation but as a partial dislocation in the hinge-type plastic zone. Prominent dislocation arrays that were emitted from a crack tip were also observed, and they were found to be of shielding type, which increases the fracture toughness of those crystals

  11. Computational issues in the simulation of two-dimensional discrete dislocation mechanics

    Science.gov (United States)

    Segurado, J.; LLorca, J.; Romero, I.

    2007-06-01

    The effect of the integration time step and the introduction of a cut-off velocity for the dislocation motion was analysed in discrete dislocation dynamics (DD) simulations of a single crystal microbeam. Two loading modes, bending and uniaxial tension, were examined. It was found that a longer integration time step led to a progressive increment of the oscillations in the numerical solution, which would eventually diverge. This problem could be corrected in the simulations carried out in bending by introducing a cut-off velocity for the dislocation motion. This strategy (long integration times and a cut-off velocity for the dislocation motion) did not recover, however, the solution computed with very short time steps in uniaxial tension: the dislocation density was overestimated and the dislocation patterns modified. The different response to the same numerical algorithm was explained in terms of the nature of the dislocations generated in each case: geometrically necessary in bending and statistically stored in tension. The evolution of the dislocation density in the former was controlled by the plastic curvature of the beam and was independent of the details of the simulations. On the contrary, the steady-state dislocation density in tension was determined by the balance between nucleation of dislocations and those which are annihilated or which exit the beam. Changes in the DD imposed by the cut-off velocity altered this equilibrium and the solution. These results point to the need for detailed analyses of the accuracy and stability of the dislocation dynamic simulations to ensure that the results obtained are not fundamentally affected by the numerical strategies used to solve this complex problem.

  12. Compound transstyloid, transscaphoid, perilunate fracture dislocation

    Directory of Open Access Journals (Sweden)

    Nadeem Ali

    2013-01-01

    Full Text Available Compound fracture dislocations of proximal carpal bones are very rare. We report a 26-year-old male, Defense personnel by profession, who sustained a compound Gustilo Anderson type IIIA transstyloid, transscaphoid, perilunate dislocation. The patient underwent primary proximal row carpectomy and stabilization with uni-planar, uni-lateral external fixator, and K-Wires. On follow-up after a year, the patient had almost negligible range of motion around wrist without any significant discomfort.

  13. Dislocations and related defects in niobium oxide structures

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J S; Hutchinson, J L; Lincoln, F J [Oxford Univ. (UK). Inorganic Chemistry Lab.

    1977-01-07

    Lattice images of the niobium oxides, structures based on the linkage of octahedral groups in continuous networks, occasionally contain features recognizable as dislocations. Since lattice imaging enables the microstructure to be resolved in greater detail, at the level of local structural organization, it is possible to determine the configuration, and also to infer the chemical composition, of dislocated areas. By treating the niobium oxide 'block' structures as superstructures of the ReO/sub 3/ (DO/sub 9/) type, the topology of dislocations can be expressed by relations between the insertion (or deletion) of one or more half-planes of cations, or of oxygen atoms only, changes in the number of crystallographic shear plane interfaces between blocks or columns, changes in (idealized) dimensions and any requisite distortion in the third dimension. Mapping the structure around a dislocation, from the lattice image, is directly equivalent to plotting the Burgers' circuit. In this way, the precise nature of a dislocating perturbation and its implications for the local chemical composition of the crystal can be directly identified. The method is exemplified by analysis of dislocations and of related extended defects of several types, associated with twinning phenomena, semicoherent intergrowth between different ReO/sub 3/-type superstructures and arrays building up a low angle boundary. The essential features of the analysis are not restricted to structures of the niobium oxide type, but can be extended to other types of polyhedron networks.

  14. Influence of Elastic Anisotropy on Extended Dislocation Nodes

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, B

    1971-09-15

    The interaction forces between the partial dislocations forming an extended dislocation node are calculated using elasticity theory for anisotropic media.s are carried out for nodes of screw, edge and mixed character in Ag, which has an anisotropy ratio A equal to 3, and in a hypothetic material with A = 1 and the same shear modulus as Ag. The results are compared with three previous theories using isotropic elasticity theory. As expected, in Ag the influence of anisotropy is of the same order as the uncertainty due to the dislocation core energy

  15. Microstructure of friction stir welded joints of 2017A aluminium alloy sheets.

    Science.gov (United States)

    Mroczka, K; Dutkiewicz, J; Pietras, A

    2010-03-01

    The present study examines a friction stir welded 2017A aluminium alloy. Transmission electron microscope investigations of the weld nugget revealed the average grain size of 5 microm, moderate density of dislocations as well as the presence of nanometric precipitates located mostly in grains interiors. Scanning electron microscope observations of fractures showed the presence of ductile fracture in the region of the weld nugget with brittle precipitates in the lower part. The microhardness analysis performed on the cross-section of the joints showed fairly small changes; however, after the artificial ageing process an increase in hardness was observed. The change of the joint hardness subject to the ageing process indicates partial supersaturation in the material during friction stir welding and higher precipitation hardening of the joint.

  16. Modeling of dislocation channel width evolution in irradiated metals

    Science.gov (United States)

    Doyle, Peter J.; Benensky, Kelsa M.; Zinkle, Steven J.

    2018-02-01

    Defect-free dislocation channel formation has been reported to promote plastic instability during tensile testing via localized plastic flow, leading to a distinct loss of ductility and strain hardening in many low-temperature irradiated materials. In order to study the underlying mechanisms governing dislocation channel width and formation, the channel formation process is modeled via a simple stochastic dislocation-jog process dependent upon grain size, defect cluster density, and defect size. Dislocations traverse a field of defect clusters and jog stochastically upon defect interaction, forming channels of low defect-density. Based upon prior molecular dynamics (MD) simulations and in-situ experimental transmission electron microscopy (TEM) observations, each dislocation encounter with a dislocation loop or stacking fault tetrahedron (SFT) is assumed to cause complete absorption of the defect cluster, prompting the dislocation to jog up or down by a distance equal to half the defect cluster diameter. Channels are predicted to form rapidly and are comparable to reported TEM measurements for many materials. Predicted channel widths are found to be most strongly dependent on mean defect size and correlated well with a power law dependence on defect diameter and density, and distance from the dislocation source. Due to the dependence of modeled channel width on defect diameter and density, maximum channel width is predicted to slowly increase as accumulated dose increases. The relatively weak predicted dependence of channel formation width with distance, in accordance with a diffusion analogy, implies that after only a few microns from the source, most channels observed via TEM analyses may not appear to vary with distance because of limitations in the field-of-view to a few microns. Further, examinations of the effect of the so-called "source-broadening" mechanism of channel formation showed that its effect is simply to add a minimum thickness to the channel

  17. [Intra-prosthetic dislocation of the Bousquet dual mobility socket].

    Science.gov (United States)

    Lecuire, F; Benareau, I; Rubini, J; Basso, M

    2004-05-01

    The Bousquet system is a dual mobility head-polyethylene polyethylene-metal cup socket. The polyethylene insert retaining the femoral head moves in the noncemented metal cup, increasing both mobility and stability. Between 1989 and 1997, seven cases of intra-prosthetic dislocation (six patients) were observed. The femoral head escaped from the polyethylene insert due to wear. On the average, this complication occurred ten Years after implantation. Risk of dislocation was high in six of the seven hips. All patients had a large sized stem screwed into the femoral neck. There was a characteristic radiological aspect with loss of the concentric head metal cup configuration. The head was applied against the upper wall of the metal cup. Surgical replacement was undertaken early in six patients by simply changing the insert without modifying the other stable components. Outcome remained good at three to eight Years. One patient underwent late surgery. The insert and the cup were replaced with a classical implant. Functional outcome was good but recurrent dislocation occurred. At mid-term, intra-prosthetic dislocation of dual mobility sockets appears to be exceptional. Dislocation results from polyethylene wear leading to failure of the insert to retain the prosthetic head. Wear is favored by direct phenomena (direct contact between neck and insert which can occur early if there is a small difference in the head and neck diameters) or indirect phenomena (factors limiting polyethylene metal-cup mobility). Surgical treatment is necessary. If undertaken early, replacement with a modular head and insert can be sufficient if the prosthesis has not loosened but the metal cup may have to be replaced in the event of metal-metal contact between the head and the cup. Prosthesis loosening, wear of the metal cup, or an identified cause of dislocation imply replacing the failing implants. Implantation of the dual mobility system is particularly interesting for patients with a high risk

  18. Dislocation morphology in deformed and irradiated niobium

    International Nuclear Information System (INIS)

    Chang, C.P.

    1977-06-01

    Niobium foils of moderate purity were examined for the morphology of dislocations or defect clusters in the deformed or neutron-irradiated state by transmission electron microscopy. New evidence has been found for the dissociation of screw dislocations into partials on the (211) slip plane according to the Crussard mechanism: (a/2) [111] → (a/3) [111] + (a/6) [111

  19. Dislocation temporo-mandibulaire bilatérale survenue lors d'une ...

    African Journals Online (AJOL)

    Risk factors predisposing to these dislocations are known and include conditions such as dimorphism, the unit's syndrome algo-dysfunctional mastication and history of dislocation. These dislocations occur most often after an effort to yawn or in cases of willful forced opening mouth. A female predominance is found in the ...

  20. Electron holography studies of the charge on dislocations in GaN

    Energy Technology Data Exchange (ETDEWEB)

    Cherns, D.; Jiao, C.G.; Mokhtari, H. [H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Cai, J.; Ponce, F.A. [Department of Physics and Astronomy, Arizona State University, Tempe, AZ85287 (United States)

    2002-12-01

    The measurement of charge on dislocations in GaN by electron holography is described. Recent results are presented showing that edge dislocations in n-doped GaN are highly negatively charged, whereas those in p-doped GaN are positively charged. It is shown that the results are consistent with a model which assumes Fermi level pinning at dislocation states about 2.5 V below the conduction band edge. The application of electron holography to screw dislocations, and the dependence of the observations on the dislocation core structure, are also discussed. (Abstract Copyright [2002], Wiley Periodicals, Inc.)