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Sample records for acromioclavicular joint dislocation

  1. Epidemiology of Isolated Acromioclavicular Joint Dislocation

    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.

  2. Arthroscopically Assisted Treatment of Acute Dislocations of the Acromioclavicular Joint

    Braun, Sepp; Beitzel, Knut; Buchmann, Stefan; Imhoff, Andreas B.

    2015-01-01

    Arthroscopically assisted treatments for dislocations of the acromioclavicular joint combine the advantages of exact and visually controlled coracoid tunnel placement with the possibility of simultaneous treatment of concomitant injuries. The clinical results of previous arthroscopically assisted techniques have been favorable at midterm and long-term follow-up. The presented surgical technique combines the advantages of arthroscopically positioned coracoclavicular stabilization with an additional suture cord cerclage of the acromioclavicular joint capsule for improved horizontal stability. PMID:26870646

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

    Marchie Anthony

    2009-01-01

    Full Text Available 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.

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

    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.)

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

    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.

  6. A new method of arthroscopic reconstruction of the dislocated acromio-clavicular joint.

    Trikha, S. P.; Acton, D.; Wilson, A. J.; Curtis, M. J.

    2004-01-01

    BACKGROUND: Symptomatic total acromio-clavicular joint dislocation (Rockwood et al. types III-VI) may be treated by surgical reconstruction. AIM: To describe an arthroscopically assisted technique to reconstruct anatomically the coraco-clavicular ligaments in acute or chronic (> 6 weeks) acromio-clavicular joint dislocation. METHODS: This new technique involves arthroscopic exposure of the coracoid process. Prior to introducing this technique, cadaveric studies were undertaken. RESULTS: Five ...

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

    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

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

    Zhang Jingwei; Li Min; He Xianfeng; Yu Yihui; Zhu Limei

    2014-01-01

    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.

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

    Qingjun Liu, Jianyun Miao, Bin Lin, Zhimin Guo

    2012-01-01

    Full Text Available 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.

  10. Type IV acromioclavicular joint dislocation associated with a mid-shaft clavicle malunion.

    Mohammed, Khalid D; Stachiw, Danielle; Malone, Alex A

    2016-01-01

    This reports presents the case of a combined clavicle fracture malunion and chronic Type IV acromioclavicular (AC) joint dislocation. The patient was seen acutely in the emergency department following a mountain bike accident at which time the clavicle fracture was identified and managed conservatively however the AC dislocation was not diagnosed. The patient presented 25 months following the injury with persistent pain and disability and was treated with clavicle osteotomy and AC stabilization. We document the clinical details, surgical treatment and outcome. PMID:26980988

  11. Type IV acromioclavicular joint dislocation associated with a mid-shaft clavicle malunion

    Khalid D Mohammed

    2016-01-01

    Full Text Available This reports presents the case of a combined clavicle fracture malunion and chronic Type IV acromioclavicular (AC joint dislocation. The patient was seen acutely in the emergency department following a mountain bike accident at which time the clavicle fracture was identified and managed conservatively however the AC dislocation was not diagnosed. The patient presented 25 months following the injury with persistent pain and disability and was treated with clavicle osteotomy and AC stabilization. We document the clinical details, surgical treatment and outcome.

  12. Comparative study on treating complete dislocation of acromioclavicular joint with three different methods

    林斌; 练克俭; 郭林新; 郭志民; 庄泽民; 刘庆军; 周亮

    2004-01-01

    Objective: To comparatively study complete dislocation of acromioclavicular joint treated with three different methods.Methods:A total of 96 patients (81 males and 15 females, aged 16-59 years, mean =45 years) with complete dislocation of acromioclavicular joint were treated with Dewar's operation ( Group A, n = 32), internal fixation with Kirschner tension band wires ( Group B, n = 44), or internal fixation with Wolter plates ( Group C, n = 20 ),respectively, in this study. Eighty-five patients suffered from acute dislocations and eleven from chronic dislocations. Results: The patients were followed up for 50 months on an average. According to Karlsson's standard, in Group A, 26 patients were assessed as good, 5 as fair and 1 as poor. In Group B, 20 patients were assessed as good, 13 as fair and 11 as poor. In Group C, 15 patients were assessed as good, 4 as fair and 1 as poor. The good and fair rates were significantly different between Group A and Group B, and between Group C and Group B, but no statistical difference was found between Group A and Group C. The operating time was ( 52.36 ± 7.24 ) minutes, ( 67.43 ± 8.11) minutes and (69.73 ±8.04) minutes in Groups A, B and C, respectively. And the hospitalizing fees were (2 400 ±270) yuan, (2 100±190) yuan and (8450±360) yuan in Groups A, B and C, respectively. Conclusions: Dewar's operation is a good and safe method with shorter operating time and lower hospitalizing fee for treating complete dislocation of acromioclavicular joint. The method is simple without the need of a second operation to remove the implants and with few complications.

  13. Acroplate--a modern solution for the treatment of acromioclavicular joint dislocation.

    Cîrstoiu, C; Rădulescu, R; Popescu, D; Ene, R; Circotă, G; Bădiceanu, Corina

    2009-01-01

    Two main ways to fix the reduction were imposed in surgical treatment of the acromioclavicular joint dislocations: fixation with trans acromioclavicular pin (Phemister method) and fixation with plate and screws type acroplate. The purpose of the present paper work is to compare immediate and later postoperative results between the two types of surgical interventions. During 2005-2007, 37 surgical reductions and fixation of acromioclavicular joint dislocations were performed in the Orthopedic-Traumatology Clinic of SUUB. In 17 cases a fixation with screws and plates type acroplate has been performed and in 20 cases with pins using the Phemister method. Sex ratio: 31 men and 8 women. Patients were aged between 17 and 56 years old. Follow up at 6 weeks, 3, 6, 12 and 18 post-operatory months. Osteosintesis material removing was done postoperatively, at 4 weeks in case of acroplate's and at 6 weeks in case of the pins. All patients treated of fixation with plate and screws acroplate type had a favorable evolution/development, starting with the shoulder joint mobilization at 24 hours postoperatively, with a complete recovery 4 weeks after the operation, at the same time with the ablation, and without immediate other late complications. As far as the patients treated by using the Phemister method are concerned, they were applied an immobilization, postoperatively. Desault bandage or the scarf for a period between 1 and 3 weeks, beginning with the shoulder joint mobilization later on and a full recovery after a minimum of 6 weeks. However, 3 of the cases showed a migration of one or both pins. Following the study, a more rapid recovery resulted, complete, and without complications of mobility in the shoulder joint, when using plate type acroplate vs pin. PMID:20108536

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

    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.

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

    Onada, Yoshihiro; Umemoto, Takahisa; Fukuda, Kimitaka; Kajino, Tomomichi

    2016-01-01

    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. PMID:27493819

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

    Umemoto, Takahisa; Fukuda, Kimitaka; Kajino, Tomomichi

    2016-01-01

    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. PMID:27493819

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

    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.

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

    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.

  19. Management of acromioclavicular joint injuries.

    Li, Xinning; Ma, Richard; Bedi, Asheesh; Dines, David M; Altchek, David W; Dines, Joshua S

    2014-01-01

    Acromioclavicular joint injuries are among the most common shoulder girdle injuries in athletes and most commonly result from a direct force to the acromion with the arm in an adducted position. Acromioclavicular joint injuries often present with associated injuries to the glenohumeral joint, including an increased incidence of superior labrum anterior posterior (SLAP) tears that may warrant further evaluation and treatment. Anteroposterior stability of the acromioclavicular joint is conferred by the capsule and acromioclavicular ligaments, of which the posterior and superior ligaments are the strongest. Superior-inferior stability is maintained by the coracoclavicular (conoid and trapezoid) ligaments. Type-I or type-II acromioclavicular joint injuries have been treated with sling immobilization, early shoulder motion, and physical therapy, with favorable outcomes. Return to activity can occur when normal shoulder motion and strength are obtained and the shoulder is asymptomatic as compared with the contralateral normal extremity. The management of type-III injuries remains controversial and is individualized. While a return to the previous level of functional activity with nonsurgical treatment has been documented in a number of case series, surgical reduction and coracoclavicular ligament reconstruction has been associated with a favorable outcome and can be considered in patients who place high functional demands on their shoulders or in athletes who participate in overhead sports. Surgical management is indicated for high-grade (≥type IV) acromioclavicular joint injuries to achieve anatomic reduction of the acromioclavicular joint, reconstruction of the coracoclavicular ligaments, and repair of the deltotrapezial fascia. Outcomes after surgical reconstruction of the coracoclavicular ligaments have been satisfactory with regard to achieving pain relief and return to functional activities, but further improvements in the biomechanical strength of these

  20. 全关节镜下治疗肩锁关节脱位%Arthroscopic treatment of acromioclavicular joint dislocation

    汪国友; 沈骅睿; 曾胜强; 徐平; 邓凯; 扶世杰

    2014-01-01

    Background The dislocation of acromioclavicular joint is a common injury clinically. This study is to investigate the treatment of acute acromioclavicular joint dislocation (Rockwood typeⅢ)and compare the clinical effect of two different ways of coracoclavicular ligament reconstruction. Methods We select the patients with fresh Rockwood type Ⅲ to V dislocation of acromioclavicular joint from January 2008 to June 2013.After randomization,1 6 cases received the reconstruction of coracoclavicular and acromioclavicular ligament arthroscopically with semitendinosus tendon (autogenous group).Among them,12 were males and 4 were females,aged 1 6-62 years old,the average age is 39.8 years old.They were followed up for 9-39 months,the average follow-up was 25.6 months;13 cases underwent the reconstruction of coracoclavicular ligament with the double Endobutton plate and Ethibond suture (Ethibond suture group),including 9 cases of male,4 cases of female,aging from 1 9 to 57 years old,the average age is 36.5 years old,were followed up for 12-35 months with a mean follow-up of 1 9.6 months.The reason of injury:12 cases of traffic injuries,9 cases of sports injury,4 cases of fall,bruise in 2 cases and 2 cases of other injuries.The time between injury to operation was 3-1 1 d,averagely 6 d.8 patients were accompanied by SLAP injury of shoulder joint (5 cases of autologous ligament group,3 cases of Ethibond suture group),3 patients were accompanied by rotator cuff injury (1 cases of autologous ligament group,2 cases of Ethibond suture group).2 patients were combined with glenohumeral joint cartilage injury (1 case of autologous ligament group 1 case,1 case of love help group),2 patients were combined with Bankart injury (both in autologous ligament group ), 1 patient was combined with glenoid fracture (Ethibond suture group).The age,sex,cause of injury,injury side and time from getting injured to operation of the two groups are without significant differences (P >0

  1. Tratamento artroscópico da luxação acromioclavicular aguda com âncoras Arthroscopic treatment of acute acromioclavicular joint dislocation using suture anchors

    Leonardo Muntada Cavinatto

    2011-01-01

    Full Text Available OBJETIVO: Apresentar os resultados clínicos e radiográficos de uma série de casos com diagnóstico de Luxação Acromioclavicular (LAC Aguda, tratados através da fixação coracoclavicular com âncoras por via artroscópica. MÉTODO: Vinte pacientes apresentando LAC com menos de 30 dias de evolução foram operados pela técnica da estabilização coracoclavicular com âncoras por via artroscópica. Duas âncoras metálicas com dois fios cada, foram inseridas no coracóide. Os fios foram amarrados sobre a clavícula passando por túneis transósseos claviculares. Para a avaliação radiográfica, foi utilizada a medida comparativa da distância coracoclavicular com o lado contralateral e a avaliação funcional através dos escores de Constant e UCLA o seguimento foi de seis meses. RESULTADO: Dos vinte casos inicialmente selecionados, seis necessitaram de novo procedimento cirúrgico e foram excluídos do estudo. Dos quatorze pacientes restantes, apenas dois mantiveram redução da articulação acromioclavicular, enquanto os demais apresentaram algum grau de desvio no decorrer da evolução. Desconsiderando os pacientes excluídos, os escores de Constant e UCLA tiveram média 94,79 (82-100 e, 32,64 (26-35, respectivamente. CONCLUSÃO: A técnica apresentou um alto índice de perda da redução ao longo da evolução de seis meses. A avaliação funcional apresentou resultado satisfatório com escore médio elevado de Evidência: Nível de Evidência: Nível III, estudo retrospectivo.OBJECTIVE: To present the clinical and radiographic results of a case series of patients with acute acromioclavicular dislocation (AAD treated by arthroscopic coracoclavicular fixation with suture anchors. METHOD: Twenty patients with AAD with less than 30 days since the injury were submitted to a coracoclavicular stabilization procedure using 2 suture anchors placed at the base of the coracoid process. Each suture anchor was connected to 2 strands of No.2

  2. Radiographic changes in the operative treatment of acute acromioclavicular joint dislocation – tight rope technique vs. K-wire fixation

    Operative treatment of higher degree acromioclavicular joint luxation is common. A new option is made available by the tight rope technique. It claims to provide adequate outcome with the use of a minimally invasive technique. First clinical studies justified its medical use, but the equivalence to established surgical methods remains unclear. We therefore analyzed radiographic data from patients that were treated with the tight rope system (TR) and compared them to those treated with K-wires (KW) fixation. Retrospective study with inclusion criteria: surgery for acromioclavicular joint luxation between 2004 and 2011, classified as Rockwood type III, no concomitant injury, first event injury. We compared pre- and post-operative X-rays with those taken at the end of treatment. Clinical data from follow-ups and radiographic data were evaluated. The main outcome variable was the remaining distance between the acromion and clavicle (ACD), as well as the coracoid process and clavicle (CCD). 27 patients (TR: n=16; KW: n=11) with comparable demographics and injury severity were included. Surgery reduced ACD (TR: p=0.002; KW: p<0.001) and CCD (TR: p=0.001; KW: p=0.003). Heterotopic ossification or postoperative osteolysis was not significantly associated with either one of the procedures. Three patients (18.75%) in the TR group showed impaired wound healing, migrating K-wires were recorded in 2 patients (18.2%) and impingement syndrome occurred in 1 patient (9.1%) with K-wires. Posttraumatic arthritis was not seen. There was a loss of reduction in 2 cases within the TR-group (12.51%) and 1 in the KW-group (9.1%). At last follow up, ACD and CCD were wider in both groups compared to the healthy side. This study shows that the Tight rope system is an effective alternative in the treatment of higher degree acromioclavicular luxation and comparable to the established methods

  3. Treatment of Chronic Acromioclavicular Joint Dislocation in a Paraplegic Patient with the Weaver-Dunn Procedure and a Hook-Plate

    Godry, Holger; Citak, Mustafa; Königshausen, Matthias; Schildhauer, Thomas A.; Seybold, Dominik

    2016-01-01

    In case of patients with spinal cord injury and concomitant acromioclavicular (AC) joint-dislocation the treatment is challenging, as in this special patient group the function of the shoulder joint is critical because patients depend on the upper limb for mobilization and wheelchair-locomotion. Therefore the goal of this study was to examine, if the treatment of chronic AC-joint dislocation using the Weaver-Dunn procedure augmented with a hook-plate in patients with a spinal cord injury makes early postoperative wheelchair mobilization and the wheelchair transfer with full weight-bearing possible. In this case the Weaver-Dunn procedure with an additive hook-plate was performed in a 34-year-old male patient with a complete paraplegia and a posttraumatic chronic AC-joint dislocation. The patient was allowed to perform his wheelchair transfers with full weight bearing on the first post-operative day. The removal of the hook-plate was performed four months after implantation. At the time of follow-up the patient could use his operated shoulder with full range of motion without restrictions in his activities of daily living or his wheel-chair transfers. PMID:27433301

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

    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. Mid-term results after operative treatment of rockwood grade III-V Acromioclavicular joint dislocations with an AC-hook-plate

    Kienast B

    2011-02-01

    Full Text Available Abstract Acromioclavicular joint dislocations often occur in athletic, young patients after blunt force to the shoulder. Several static and dynamic operative procedures with or without primary ligament replacement have been described. Between February 2003 and March 2009 we treated 313 patients suffering from Rockwood III-V lesions of the AC joint with an AC-hook plate. 225 (72% of these patients could be followed up. Mean operation time was 42 minutes in the conventional group and 47 minutes in the minimal invasive group. The postoperative pain on a scale from 1 to 10 (VAS-scale was rated 2.7 in the conventional group and 2.2 in the minimal invasive group. Taft score showed very good and good results in 189 patients (84%. Constant score showed an average of 92.4 of 100 possible points with 89% excellent and good results and 11% satisfying results. All patients had some degree of pain or discomfort with the hookplate in place. These symptoms were relieved after removal of the plate. The overall complication rate was 10.6%. There were 6 superficial soft tissue infections, 1 fracture of the acromion, 7 redislocations after removal of the hook-plate. We observed 4 broken hooks which could be removed at the time of plate removal, 4 seromas and 2 cases of lateral clavicle bone infection, which required early removal of the plate. We can conclude that clavicle hook plate is a convenient device for the surgical treatment of Rockwood Grade III-V dislocations, giving good mid-term results with a low overall complication rate compared to the literature. Early functional therapy is possible and can avoid limitations in postoperative shoulder function.

  6. Clinical results of coracoacromial ligament transfer in acromioclavicular dislocations: A review of published literature

    Sood Aman

    2008-01-01

    Full Text Available Acromioclavicular joint dislocations are common injuries, which typically occur with trauma in young men. Treatment recommendations for these injuries are highly variable and controversial. There are greater than 100 surgical techniques described for operative treatment of this injury. One of the most widely recommended methods of surgical reconstruction for acromioclavicular joint dislocations is to utilize the coracoacromial ligament for stabilization of the distal clavicle. Several modifications of this procedure have been described which have involved adjunct coracoclavicular fixation or fixation across acromioclavicular joint. Although the literature is replete with descriptive papers, there is paucity of studies evaluating the surgical outcome of this procedure. We systematically reviewed the English language published literature in peer reviewed journals (Medline, EMBASE, SCOPUS and assigned a level of evidence for available studies. We critically reviewed each paper for the flaws and biases and then evaluated the comparable clinical outcomes for various procedures and their modifications. The published literature consists entirely of case series (Level IV evidence with variability in surgical technique and outcome measures. On review there is low level evidence to support the use of coracoacromial ligament for acromioclavicular dislocation but it has been associated with high rate of deformity recurrence. Adjunct fixation does not improve clinical results when compared to isolated coracoacromial ligament transfer. This is in part because of the high incidence of fixation related complications. Similar results are reported with coracoacromial ligament reconstruction for acute and chronic cases. The development of secondary acromioclavicular joint symptoms with distal clavicle retention is poorly reported with the incidence rate varying from 12% to 32%. Despite this, the retention or excision of distal clavicle did not affect overall

  7. 关节镜下喙锁韧带增强术治疗肩锁关节脱位%Arthroscopic treatment of acute acromioclavicular joint dislocations by coracoacromial ligament augmentation and suture

    皇甫小桥; 赵金忠; 何耀华; 杨星光; 刘旭东; 刘闻欣; 王海明

    2013-01-01

    目的:研究关节镜下缝线钢板增强喙锁韧带术治疗肩锁关节脱位的近期治疗效果。方法2010年3月至2011年3月,在关节镜下使用膝关节韧带重建技术的缝线钢板(德国 ASCULAP 公司, B′BRAUN)增强重建喙锁韧带(三角韧带与斜方韧带),治疗 Rockwood Ⅲ型9例、Ⅴ型3例新鲜肩锁关节脱位。行 X线片、美国肩肘关节外科医师(America Shoulder Elbow Surgeons,ASES)评分和 Constant 评分,随访12~18个月。结果 ASES 评分:术前28.7分,术后86.9分;Constant 评分:术前24分,术后91分。治疗组 X线片显示,肩锁关节复位良好。术后1年,91.7%(11/12)病例获得满意治疗效果,83.3%(10/12)恢复到术前运动水平,仅有1例出现肩锁关节半脱位。结论关节镜下缝线钢板喙锁韧带增强术治疗肩锁关节脱位,早期可以获得满意的治疗效果,术后复位良好,并发症少。%Objective Acromioclavicular joint dislocation is commonly seen in shoulder joint injuries. Dysfunction as well as pain and discomfort usually occurred when the integrity of shoulder is damaged,for the acromioclavicular (AC)joint is involved in the connection between the scapula and the body as well as the activities of shoulder joint.Therefore,a consensus has been reached to treat severe AC joint dislocation by surgery.Based on different anatomical and functional cognition,methods for AC joint dislocation are various,which are typically performed by incision to reconstruct its stability and restore function.Attempts had been made by many doctors in the reconstruction of AC joint dislocation with the development of arthroscopy.From March 2010 to March 2011,obvious therapeutic effect was obtained in treating Rockwood type Ⅲ and Ⅴ AC joint dislocation arthroscopically with the suture plate used for the reconstruction of ligaments of knee joint to augment the reconstructed CC ligaments (conoid ligament and trapezoid ligament).Methods From March 2010 to March 2011

  8. COMPARATIVE ANALYSIS OF AUTOGRAFT TECHNIQUE AND CLAVICULAR HOOK PLATE IN GRADE 3 ACROMIOCLAVICULAR DISLOCATIONS

    Rahul Narayan; Ojas

    2016-01-01

    OBJECTIVE To evaluate clinical outcome of clavicular hook plate and autograft technique in the surgical treatment of Rockwood Grade-III acromioclavicular joint dislocation. METHODS Fifteen patients were operated using standard clavicular hook plate and another fifteen patients were operated using autograft technique. After a minimum follow-up of one year, clinical assessment was done using Constant-Murley Score. Statistical evaluation was done using SPSS ver. 21.0. RES...

  9. Three Endobutton plates in reconstruction of coracoclavicular ligament for the dislocations of the acromioclavicular joint%三Endobutton钢板解剖重建喙锁韧带治疗肩锁关节脱位

    吕书军; 曹勇; 洪晔; 蒋栋; 周广(钅监)

    2012-01-01

    目的 探讨三Endobutton钢板解剖重建喙锁韧带治疗肩锁关节脱位的初步临床疗效.方法 对25例肩锁关节脱位患者应用三Endobutton钢板解剖重建喙锁韧带治疗的临床疗效进行分析.结果 25例均获随访,时间14~29个月.X线检查证实肩锁关节脱位均完全复位.肩关节外展活动范围术前为40°~80°,术后为140°~150°.肩关节功能按Constant标准,评分术前为(66.5±3.2)分,术后3个月为(90.5±2.3)分,术后6个月为(93.5±3.1)分.结论 三Endobutton钢板解剖重建喙锁韧带治疗肩锁关节脱位固定确实,不损伤关节面,术后患者可以早期功能锻炼,无需二次手术,疗效满意.%Objective To evaluate the clinical results of three Endobutton plates in reconstruction of coracoclavicular ligament for the dislocations of the acromioclavicular joint. Methods 25 patients with the dislocations of the acromi-oclavicular joint were reviewed retrospectively. The Constant evaluation system were used to analyze the clinical effects of triple button plates technique. Results All patients obtained the follow-up and the time was 14 to 29 months. Preoperative shoulder abduction range was 40° to 80°. Postoperative abduction range was 140° to 150°. Pre-operative shoulder function according to the standard of Constant score was 66. 5 ± 3. 2 points. After 3 months, Constant score was ( 90. 5 ± 2. 3 ) points, and 6 months Constant score was ( 93. 5 ± 3. 1 ) points. Conclusions The treatment of dislocations of acromioclavicular joint by using reconstruction of coracoclavicular ligament has satisfactory functional outcome and a few trauma in joint surface, without the secondary operation.

  10. Treatment of Rockwood type Ⅲ acromioclavicular joint dislocation with endobutton technique%应用 Endobutton 带袢钢板技术治疗RockwoodⅢ型肩锁关节脱位

    宋哲; 张堃; 朱养均; 李忠; 庄岩; 魏巍; 杨娜

    2015-01-01

    Background Acromioclavicular joint dislocation is a common injury which often occurs in heavy manual workers and young athletes.It is usually caused by collision of the shoulder on the ground.Acromioclavicular joint dislocation of Rockwood type Ⅲ often needs surgical treatment. There are several kinds of operation methods reported in the literature,but no universally accepted technique exists.From June 2010 to June 2013,21 patients of Rockwood type Ⅲ acromioclavicular joint dislocation were treated with Endobutton technique in our hospital,shoulder functional and radiological evaluations were performed and the outcome is encouraging.Methods (1 )General information:Twenty-one patients were included in this study.Patients were 14 males and 7 females. Nine cases were on the left side and 12 cases were on the right side.The age ranged from 1 9 to 52 with an average of 31.2 years.The causes were traffic injury in 8 cases,fall damage in 9 cases,sports injury in 2 cases and heavy object hit injury in 2 cases.All patients were diagnosed as acromioclavicular joint dislocation of Rockwood type Ⅲ without clavicle fracture,multiple fractures,closed chest injury and cerebral injury.The clinical presentations included pain over the lateral side of clavicle with its distal end protruding upward,tenderness and a feeling of floating;X-ray examinations revealed that the distal clavicle was higher than the acromion.21 cases were all fresh dislocations without neurovascular injuries;The operation time was 1-5 days after injury.(2)Operation method:After successful general anesthesia or cervical plexus block,the patient was in supine or “beach chair”position with head turned to the uninjured side.The straight incision was extended longitudinally from coracoid upward to the posterior edge of clavicle.The skin and subcutaneous tissue was incised layer by layer.The deltoid muscle was bluntly separated and the periosteum was stripped to expose acromioclavicular joint

  11. 关节镜下四骨道双束固定治疗急性肩锁关节Rockwood Ⅴ型脱位%Arthroscopic fixation in the treatment of Rockwood Ⅴ acute acromioclavicular joint dislocation

    陆伟; 王大平; 朱伟民; 欧阳侃; 柳海峰; 彭亮权; 李皓; 冯文哲

    2014-01-01

    Background Treatment methods for acromioclavicular joint dislocation of Rockwood type V are numerous.The commonly used is the open surgery with large trauma (by clavicular hook plate fixation).In recent years,some scholars use clavicle-coracoid screws fixation method under arthroscopy,but the screws need to be removed after 6 weeks; there are also scholars using arthroscopic double Endobutton loops single bundle fixation method with good effect,but they found suture rupture between the Endobutton,redislocation or fracture,bone absorption under the loops in some patients. This article investigates the method of arthroscopic procedure with four-tunnel quadruple double-bundle Endobutton double-bundle fixation via self-designed positioning apparatus in the treatment of acute acromioclavicular joint (ACJ)Rockwood Ⅴ degree dislocations and their short-term therapeutic effect.Methods (1)Patient selection:12 patients (9 male and 3 female)with acute acromioclavicular joint dislocation of Rockwood type V were selected from October 2010 to June 2013. Their average age is 28.2 years.with sports injury in 10 cases and fall injury in 2 cases.All patients received surgical repair within 2 weeks after injury.The operations were performed by the same senior surgeon.(2)Preoperative bone tunnel positioning design:All patients had CT scan in the position of 90°internal rotating of bilateral shoulder joint (palm down).Measure the angle of scapular long axis and coronal section (A)separately,make the line in the coracoid neck parallel to the long axis of scapula (S),and then measure the width of parallel line in the part of coracoid neck (P).The midpoint of the coracoid neck is the center between the two preparatively drilled bone tunnels.Make the cross line vertical to line P,and the bone tunnels are located in the I and II quadrant.The distance between two bone tunnels is 6 mm.(3 )Surgical techniques:According to the data of preoperative measurement of bone tunnel,the self

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

    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. PMID:26637681

  13. Arthroscopic coracoclavicular ligament reconstruction for Rockwood type Ⅲ acromioclavicular joint dislocations%肩关节镜下喙锁韧带重建术治疗 RockwoodⅢ型肩锁关节脱位的疗效研究

    李奉龙; 姜春岩

    2015-01-01

    目的:分析采用肩关节镜下喙锁韧带重建术治疗 Rockwood Ⅲ型肩锁关节脱位的临床疗效。方法回顾性研究2013年2月至2014年1月连续收治并获得随访的21例 Rockwood Ⅲ型肩锁关节脱位患者的资料。其中男性17例,女性4例。平均年龄42.8岁,平均受伤到手术时间11.1 d。所有患者均于肩关节镜下应用同种异体肌腱重建喙锁韧带并高强度缝线捆扎固定喙锁间隙治疗肩锁关节脱位。术后定期随访,记录患侧肩关节活动范围,并采用疼痛视觉模拟评分(visual analogue score,VAS)、ASES(American shoulder and elbow surgeons)评分及 UCLA(university of California Los Angeles)评分评价患者肩关节功能状况;同时拍摄肩关节正位、侧位及腋位 X 线片,评估是否有肩锁关节复位丢失。结果21例患者术后平均随访(14.6±3.9)个月。末次随访时肩关节平均前屈上举为173.9°±10.3°,体侧外旋为59.5°±14.3°,内旋为第12胸椎体水平,平均 UCLA 评分为(34.1±2.5)分,平均 ASES 评分为(95.5±4.7)分,平均 VAS 评分(0.3±0.6)分。末次随访拍摄肩关节 X 线片未发现肩锁关节复位丢失。结论采用肩关节镜下喙锁韧带重建术治疗 Rockwood Ⅲ型肩锁关节脱位的临床疗效满意,患者术后可获得良好的肩关节功能。%Background Dislocation of the acromioclavicular joint is a common injury of shoulder girdle.For the dislocation of acromioclavicular joint of Rockwood type Ⅰ and type Ⅱ,patient can obtain satisfactory result from conservative treatment; For the severe dislocation such as Rockwood type Ⅳ and type Ⅴ,operative treatment should be a good choice.However,for the patients of Rockwood type Ⅲ dislocation,the treatment is still controversial.With the development of minimally invasive technique,arthroscopic ligament reconstruction is gradually widely used in the treatment of acromioclavicular joint dislocation.Shoulder arthroscopic operation has the

  14. Type RockwoodIII in the treatment of small incision of clavicular hook plate for acromioclavicular joint dislocation in 66 cases%小切口锁骨钩钢板治疗RockwoodIII型肩锁关节脱位66例

    李克军; 邹方亮; 邹孝军; 杨志乐

    2013-01-01

      Objective To summarize the operation method and clinical effect of dislocation of small incision of clavicular hook plate in treatment of type RockwoodIII shoulder. Methods From 2004 January ~ 2012 year in January, the treatment of 66 cases of RockwoodIII type acromioclavicular joint dislocation were treated with clavicular hook plate, with only the clavicular hook plate, repair of acromioclavicular joint capsule and the acromioclavicular ligament, not deliberately repair of coracoclavicular ligament. Reset X ray to evaluate the postoperative dislocation of acromioclavicular joint, shoulder joint function exercise. Remove the clavicular hook plate in 9 ~ 18 months after operation, 11 months after operation on the average. Through the bilateral shoulder joints in patients with normal and weight-bearing flms, evaluation of acromioclavicular joint dislocation after operation, after taking out the internal fixation of shoulder joint function and repair and no repair of coracoclavicular ligament of shoulder joint function infuence. Results All cases were followed up, followed up for 15 ~ 32 months, an average of 20 months follow-up, according to the function evaluation standard patients, excellent in 40 cases, good in 26 cases. Conclusion The small incision of clavicular hook plate in treatment of acromioclavicular joint dislocation with RockwoodIII type acromioclavicular joint anatomic and biomechanical characteristics, reliable fxation, coracoclavicular ligament can repair, postoperative early functional exercise, is worthy of promotion.%  目的总结小切口锁骨钩钢板治疗RockwoodIII型肩锁关节脱位的手术方法和临床疗效。方法2004年1月至2012年1月,应用锁骨钩钢板治疗66例RockwoodIII型肩锁关节脱位,术中仅行锁骨钩钢板固定,修复肩锁关节关节囊和肩锁韧带,未刻意修复喙锁韧带。术后X光片评估肩锁关节脱位的复位,行肩关节功能锻炼。锁骨钩钢板在术后9~18

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

    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.

  16. COMPARATIVE ANALYSIS OF AUTOGRAFT TECHNIQUE AND CLAVICULAR HOOK PLATE IN GRADE 3 ACROMIOCLAVICULAR DISLOCATIONS

    Rahul Narayan

    2016-04-01

    Full Text Available OBJECTIVE To evaluate clinical outcome of clavicular hook plate and autograft technique in the surgical treatment of Rockwood Grade-III acromioclavicular joint dislocation. METHODS Fifteen patients were operated using standard clavicular hook plate and another fifteen patients were operated using autograft technique. After a minimum follow-up of one year, clinical assessment was done using Constant-Murley Score. Statistical evaluation was done using SPSS ver. 21.0. RESULTS Mean age group was 31.44±7.8 years. Average constant shoulder score for the hook plate group was 81.3 (Range 74–89 and that for autograft technique group was 91.7 (Range 88–97. CONCLUSION Autograft technique was found to be superior in terms of functional outcome when compared to clavicular hook plate. Such superiority can be attributed to the biologic nature of coracoclavicular ligament reconstruction in the autograft technique.

  17. Acromioclavicular dislocation: postoperative evaluation of the coracoclavicular ligaments using magnetic resonance☆

    Faria, Rafael Salomon Silva; Ribeiro, Fabiano Rebouças; Amin, Bruno de Oliveira; Tenor Junior, Antonio Carlos; da Costa, Miguel Pereira; Filardi Filho, Cantídio Salvador; Batista, Cleber Gonçalves; Brasil Filho, Rômulo

    2015-01-01

    Objective To radiologically evaluate the healing of the coracoclavicular ligaments after surgical treatment for acromioclavicular dislocation. Methods Ten patients who had undergone surgical treatment for acromioclavicular dislocation via a posterosuperior route at least one year earlier were invited to return for radiological assessment using magnetic resonance. This evaluation was done by means of analogy with the scale described in the literature for studying the healing of the anterior cruciate ligament of the knee and for measuring the healed coracoclavicular ligaments. Results A scar structure of fibrous appearance had formed in 100% of the cases. In 50% of the cases, the images of this structure had a good appearance, while the other 50% were deficient. Conclusion Late postoperative evaluation using magnetic resonance, on patients who had been treated for acute acromioclavicular dislocation using a posterosuperior route in the shoulder, showed that the coracoclavicular ligaments had healed in 100% of the cases, but that this healing was deficient in 50%. PMID:26229916

  18. Acromioclavicular Dislocation Associated with Coracoid Process Fracture: Report of Two Cases and Review of the Literature

    Ozkan Kose

    2015-01-01

    Full Text Available Acromioclavicular dislocation associated with coracoid process fracture is a rare injury. Herein we reported two further cases with such combination of injuries and reviewed all previously published cases in current literature. In this review, we discussed the demographic characteristics, mechanism of injury, diagnosis, and treatment options extensively.

  19. Acromioclavicular Dislocation Associated with Coracoid Process Fracture: Report of Two Cases and Review of the Literature

    Kose, Ozkan; Canbora, Kerem; Guler, Ferhat; Kilicaslan, Omer Faruk; May, Hasan

    2015-01-01

    Acromioclavicular dislocation associated with coracoid process fracture is a rare injury. Herein we reported two further cases with such combination of injuries and reviewed all previously published cases in current literature. In this review, we discussed the demographic characteristics, mechanism of injury, diagnosis, and treatment options extensively. PMID:26491588

  20. Acromioclavicular Dislocation Associated with Coracoid Process Fracture: Report of Two Cases and Review of the Literature

    Ozkan Kose; Kerem Canbora; Ferhat Guler; Omer Faruk Kilicaslan; Hasan May

    2015-01-01

    Acromioclavicular dislocation associated with coracoid process fracture is a rare injury. Herein we reported two further cases with such combination of injuries and reviewed all previously published cases in current literature. In this review, we discussed the demographic characteristics, mechanism of injury, diagnosis, and treatment options extensively.

  1. 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

    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

  2. Acromioclavicular Joint Dislocation of Types Rockwood Ⅲ, Ⅳ and Ⅴ Treated with Coracoclavicular Bolt Combined with Beak-shoulder Ligament Shif%喙锁螺钉结合喙肩韧带移位治疗Rockwood Ⅲ型、Ⅳ型、Ⅴ型肩锁关节脱位

    谢伟; 郑建平; 黎高明; 吴向科; 傅格深

    2012-01-01

    [目的]探讨喙锁螺钉结合喙肩韧带移位治疗RockwoodⅢ型、Ⅳ型、Ⅴ型肩锁关节脱位的临床疗效.[方法]对32例RockwoodⅢ型、Ⅳ型、Ⅴ型肩锁关节脱位患者采用喙锁螺钉结合喙肩韧带移位治疗,采用Karlasson标准,分析其临床疗效.[结果]术后随访9~21个月,平均13个月,其中A级28例,B级4例,术后均未出现神经血管损伤、螺钉失败等严重并发症.[结论]喙锁螺钉结合喙肩韧带移位是治疗肩锁关节脱位一种有效的治疗方法.%[Objective] To investigate the effects of acromioclavicular joint dislocation of types Rockwood Ⅲ, IV and V treated with coracoclavicular bolt combined with beak-shoulder ligament shift. [Method] Take Karlasson standard to 32 cases, analyse the clinical effect. [Result]Followed up for 9~ 21m after operation, 28 cases were of level A, 4 level B, without nerve or vessel injury or failure bolt or other severe complication. [Conclusion] Coracoclavicular bolt combined with beak-shoulder ligament shift is an effective method for acromioclavicular joint dislocation.

  3. [Arthroscopically assisted techniques for treatment of acute and chronic acromioclavicular joint injuries].

    Braun, S; Imhoff, A B; Martetschläger, F

    2015-05-01

    Acute and chronic acromioclavicular (AC) joint dislocation is frequently encountered in the routine clinical practice. This injury can lead to significant impairment of shoulder girdle function. Therapy based on the severity of injury is recommended to re-establish correct shoulder function. The static radiographic Rockwood classification is used to define the degree of dislocation but the clinical aspects and functional x-ray imaging of horizontal AC joint instability should also be considered for selection of the appropriate procedure. Rockwood grades I and II injuries are treated non-operatively with early functional exercise. The approach for Rockwood grade III injuries should be individual and patient-specific, with non-surgical procedures for low functional requirement patients with a high risk for surgical interventions. For patients with high demands on shoulder function surgery is recommended. A detailed diagnostic assessment frequently reveals Rockwood grade III injuries to be type IV injuries. Rockwood types IV and V AC joint dislocations require surgery for sustained stability. Treatment of acute injuries is recommended within 1-3 weeks after trauma but there is no clear evidence of a cut-off for the presence of chronic injuries. Various surgical techniques have been described in the literature. This article presents an arthroscopically assisted technique that addresses both vertical and horizontal instability of the AC joint. PMID:25964020

  4. Reconstruction of chronic acromioclavicular joint disruption with artificial ligament prosthesis

    Devendra Kumar Chouhan; Uttam Chand Saini; Mandeep Singh Dhillon

    2013-01-01

    Objective:Management of Rockwood type 3 acromioclavicular disruptions is a matter of debate.Should we adopt conservative or operative measures at first presentation? It is not clear but most of the evidences are in favour of conservative management.We present our experience in managing these patients surgically.Methods:We present a prospective series of eight cases of chronic Rockwood type 3 acromioclavicular joint disruptions treated surgically.Anatomical reconstruction of the coracoclavicular ligament was done by artificial braided polyester ligament prosthesis.Results:All the patients were able to perform daily activities from an average of the 14th postoperative day.All patients felt an improvement in pain,with decrease in average visual analogue scale from preoperative 6.5 points (range 3-9 points) to 2.0 points (range 0-5 points),Constant score from 59% to 91% and American Shoulder and Elbow Surgeons shoulder score from 65 to 93 points postoperatively.These results improved or at least remained stationary on midterm follow-up,and no deterioration was recorded at an average follow-up of 46 months.Conclusion:This midterm outcome analysis of the artificial ligament prosthesis is the first such follow-up study with prosthesis.Our results are encouraging and justify the further use and evaluation of this relatively new and easily reproducible technique.

  5. Relationship between MRI and clinical findings in the acromioclavicular joint

    Objective: To determine the relationship between the magnetic resonance (MR) appearance of the acromioclavicular (AC) joint and the physical findings. Design: A total of 116 consecutive patients underwent routine MR imaging (MRI) of the shoulder over an 18-month period. All MR studies were interpreted by a blinded, experienced musculoskeletal radiologist. Eleven variables were studied: the presence of osteophytes; fluid in the joint; fluid outside the joint; high signal in the clavicle or in the acromion; fluid in the subacromial bursa; irregularity of the joint margins; bulging of the capsule; widening of the joint; the age of the patient; and the presence of a rotator cuff tear. The clinical information was supplied by an experienced shoulder surgeon blinded to the MRI findings. A control group of 23 normal volunteers was also studied. Results: The only statistically significant correlation (P=0.0249) was between high signal in the distal clavicle and degenerative changes found clinically. A weaker relationship existed between fluid in the joint and the clinical examination and between increasing degenerative changes and advancing age. Otherwise, no material relationship was found between any of the other MR abnormalities and the clinical picture. Conclusion: There appears to be no real correlation between the MR appearances and the clinical findings in the AC joint. (orig.)

  6. Fratura extra-articular da extremidade medial da clavícula associada à luxação acromioclavicular tipo IV: relato de caso Extra-articular fracture of the medial end of the clavicle associated with type IV acromioclavicular dislocation: case report

    Mário Chaves Correa

    2011-10-01

    Full Text Available Ocorrendo isoladamente, as fraturas da clavícula e as luxações acromioclaviculares são lesões muito comuns. A combinação de uma luxação acromioclavicular e de uma fratura do terço lateral da clavícula não é rara. Entretanto, existem muito poucos casos descritos de luxações acromioclaviculares associadas a fraturas do terço médio da clavícula; aquelas associadas a fraturas do terço medial são ainda mais raras. Nós reportamos o caso de um indivíduo adulto do sexo masculino que sofreu uma luxação acromioclavicular (tipo IV associada a uma fratura extra-articular desviada da extremidade medial da clavícula (grupo 3 de Almann em um acidente ciclístico. O paciente foi tratado na fase aguda com redução aberta e fixação interna das duas lesões. Na avaliação clínica, 12 meses após a cirurgia, o paciente apresentava-se assintomático, com mobilidade ativa e passiva completa, força e resistência normais e simetria das cinturas escapulares. As radiografias e a tomografia computadorizada tridimensional mostravam subluxação posterossuperior persistente da articulação acromioclavicular e consolidação anatômica da fratura clavicular.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

  7. Modified Weaver-Dunn Procedure Versus The Use of Semitendinosus Autogenous Tendon Graft for Acromioclavicular Joint Reconstruction

    Hegazy, Galal; Safwat, Hesham; Seddik, Mahmoud; Al-shal, Ehab A.; Al-Sebai, Ibrahim; Negm, Mohame

    2016-01-01

    Background: The optimal operative method for acromioclavicular joint reconstruction remains controversial. The modified Weaver-Dunn method is one of the most popular methods. Anatomic reconstruction of coracoclavicular ligaments with autogenous tendon grafts, widely used in treating chronic acromioclavicular joint instability, reportedly diminishes pain, eliminates sequelae, and improves function as well as strength. Objective: To compare clinical and radiologic outcomes between a modified Weaver-Dunn procedure and an anatomic coracoclavicular ligaments reconstruction technique using autogenous semitendinosus tendon graft. Methods: Twenty patients (mean age, 39 years) with painful, chronic Rockwood type III acromioclavicular joint dislocations were subjected to surgical reconstruction. In ten patients, a modified Weaver-Dunn procedure was performed, in the other ten patients; autogenous semitendinosus tendon graft was used. The mean time between injury and the index procedure was 18 month (range from 9 – 28). Clinical evaluation was performed using the Oxford Shoulder Score and Nottingham Clavicle Score after a mean follow-up time of 27.8 months. Preoperative and postoperative radiographs were compared. Results: In the Weaver-Dunn group the Oxford Shoulder Score improved from 25±4 to 40±2 points. While the Nottingham Clavicle Score increased from 48±7 to 84±11. In semitendinosus tendon graft group, the Oxford Shoulder Score improved from 25±3 points to 50±2 points and the Nottingham Clavicle Score from 48±8 points to 95±8, respectively. Conclusion: Acromioclavicular joint reconstruction using the semitendinosus tendon graft achieved better Oxford Shoulder Score and Nottingham Clavicle Score compared to the modified Weaver-Dunn procedure. PMID:27347245

  8. Acromioclavicular joint reconstruction with coracoacromial ligament transfer using the docking technique

    Gobezie Reuben

    2009-01-01

    Full Text Available Abstract Background Symptomatic Acromioclavicular (AC dislocations have historically been surgically treated with Coracoclavicular (CC ligament reconstruction with transfer of the Coracoacromial (CA ligament. Tensioning the CA ligament is the key to success. Methods Seventeen patients with chronic, symptomatic Type III AC joint or acute Type IV and V injuries were treated surgically. The distal clavicle was resected and stabilized with CC ligament reconstruction using the CA ligament. The CA ligament was passed into the medullary canal and tensioned, using a modified 'docking' technique. Average follow-up was 29 months (range 12–57. Results Postoperative ASES and pain significantly improved in all patients (p = 0.001. Radiographically, 16 (94% maintained reduction, and only 1 (6% had a recurrent dislocation when he returned to karate 3 months postoperatively. His ultimate clinical outcome was excellent. Conclusion The docking procedure allows for tensioning of the transferred CA ligament and healing of the ligament in an intramedullary bone tunnel. Excellent clinical results were achieved, decreasing the risk of recurrent distal clavicle instability.

  9. Static and functional ultrasonographic picture shoulder and acromioclavicular joints in normal and at hypermobility

    Litvin Yu.P.

    2012-01-01

    Full Text Available Studying of anatomy humeral and acromioclavicular joints according to static and functional ultrasonography in norm and at hypermobility was an objective of this research. For the decision of an object in view we had been surveyed 45 persons at the age from 15 till 59 years (middle age has made 32,4±1,6 year, from them 32 men and 13 women. To clinical signs of hypermobility an investigated contingent have divided on two groups: the basic – 15 patients and control – 30 patients. It is established that humeral and acromioclavicular joints on ultrasonograms the features have display of elements. In research are described not changed soft tissue and bone structures, and also variants of their normal structure. By means of functional ultrasonography the basic signs of instability humeral and acromioclavicular joints have been defined.

  10. Acromioclavicular joint cyst: nine cases of a pseudotumor of the shoulder

    (1) To analyse the imaging appearances of nine patients with acromioclavicular joint cysts presenting as shoulder masses for tumor staging with operative, histopathological and joint aspiration findings. Retrospective review of imaging and correlation with clinical, operative and surgical notes. Images were reviewed by two musculoskeletal radiologists by consensus. Nine patients who presented clinically with a shoulder mass were evaluated by radiographs (n=9), ultrasound (n=1), conventional arthrography (n=3), MRI (n=6; with direct MR arthrography n=2, indirect MR arthrography n=4). All patients had a focal mass superior to the AC joint, with a size ranging from 1.5 cm to 6 cm and a mean of 3.27 cm. Correlation was available with surgery (n=7), histopathology (n=2) and cyst aspiration (n=2). Two patients were managed conservatively. Geyser sign was positive in all three arthrograms. All MRIs revealed extensive rotator cuff tears with a column of fluid extending from the glenohumeral joint through the rotator cuff tear into the acromioclavicular joint and acromioclavicular cyst. Chondrocalcinosis was seen in the acromioclavicular joint cyst (n=2) and in the glenohumeral joint (n=1). Aspirate in two patients contained calcium pyrophosphate dihydrate crystals. (orig.)

  11. 肩锁关节脱位的诊断与治疗%Diagnosis and treatment of acromioclavicular dislocation

    黄高; 王金华; 孔建中

    2012-01-01

    The acromioclavicular dislocation is a type of common shoulder athletic injury in clinic , and its incidence accounted for 12% of the local sites injuries. At present,The acute dislocation of Rockwood type I , II was recommended to be managed non -operatively, while acute dislocation of type IV, V and VI operatively. But there still exist controversial in the treatment of acute dislocation of type III. In this peper, the authors have reviewed the current status of treatment of acromioclavicular dislocation .%肩锁关节脱位是临床常见的肩部运动损伤.目前,临床认为Rockwood Ⅰ、Ⅱ型急性脱位应行非手术治疗,Ⅳ、V及Ⅵ型急性脱位应行手术治疗,但对Ⅲ型急性脱位是采取非手术治疗还是手术治疗仍存在争议.本文对肩锁关节脱位的治疗现状进行综述.

  12. Acromioclavicular joint separations grades I-III: a review of the literature and development of best practice guidelines.

    Reid, Duncan; Polson, Kate; Johnson, Louise

    2012-08-01

    Acromioclavicular joint (ACJ) separation injuries are common injuries among sporting populations. ACJ separations are graded according to severity from grade I being a mild sprain to grade VI, which is severe dislocation with displacement. There is consensus in the literature that grade I-III ACJ separations are managed conservatively and grades IV-VI are managed surgically. Despite conservative care being recommended for lesser grades of injury, there is very little evidence in the literature as to what constitutes conservative care. Therefore, the purpose of this paper was, first, to review the relevant anatomy and kinematics of the ACJ and, second, to review the literature relating to current evidence of conservative management of ACJ injury. Using this data, a best practice guideline for conservative rehabilitation in grade I-III ACJ separations was developed. For the conservative management, a literature search was undertaken using the following databases in the Auckland University of Technology's electronic library resources; MEDLINE, CINAHL, SPORTDiscus™ and the Cochrane Library. The following keywords or phrases were used: 'acromioclavicular joint separations', 'injury', 'dislocations', 'rehabilitation', 'conservative care', 'physiotherapy' and 'exercise'. A total of 24 articles was identified. There were no randomized controlled trials (RCTs) that investigated conservative treatment for grade I-III ACJ sprains. Therefore, a narrative review was formulated covering the anatomy and biomechanics of the ACJ, injury mechanisms and relevant literature reviewed covering rehabilitation principles. Conservative management of grade I-III ACJ separations is still the main recommendation following this review. A best practice guideline for managing grade I-III ACJ separations is presented to help guide clinicians until well constructed RCTs are carried out to improve the conservative management of ACJ injuries. PMID:22784232

  13. Shoulder tendinitis and osteoarthrosis of the acromioclavicular joint and their relation to sports.

    Stenlund, B

    1993-01-01

    A sample of 207 men from the construction industry was studied using an epidemiological technique of cross-sectional design to investigate if sport activities involving the arms increase the risk of developing shoulder tendinitis or osteoarthrosis of the acromioclavicular joint. The relative risk for shoulder tendinitis was estimated to be 9.5 on the right side, and 4.9 on the left side for a lifetime of sport activity exceeding 8399 h. Subjects who reported both extremely high physical load ...

  14. Nonoperative management of a sagittal coracoid fracture with a concomitant acromioclavicular joint separation

    Thomas Kristen

    2010-01-01

    Full Text Available Separation of the acromioclavicular joint in conjunction with a coracoid fracture is a rare injury. Treatment decisions are traditionally based on the level of the fracture, the status of the coracoclavicular ligament and the activity level of the patient. We present a novel coracoid fracture pattern treated nonoperatively in a young, active patient and a thorough review of the literature regarding this topic.

  15. Axial and tangential views of the acromioclavicular joint: the introduction of new projections

    CHEN Wei; ZHAGN Qi; SU Yan-ling; ZHANG Ze-kun; HOU Zhi-yong; PAN Jin-she; ZHANG Xiao-lin; ZHANG Ying-ze

    2012-01-01

    Background Routine anteroposterior radiographs of the acromioclavicular (AC) joint with or without weight bearing have limitations in demonstrating the AC joint.Transarticular fixation with Kirschner wire is a treatment choice for AC dislocations.However,percutaneous fixation of the AC joint is technically demanding.The C-arm fluoroscopy can be used as routine intraoperative guidance to facilitate this procedure.The current study aims to introduce new projections,the axial and tangential views of AC joint,to help evaluate the severity of the injury and facilitate the percutaneous procedure.Methods Three shoulder specimens were used to find the projection directions of the axial and tangential views of the AC joint by using the digital radiography (DR) unit.The axial and tangential views were taken of 20 adult volunteers by referencing the projection directions determined in the shoulder specimens.The angles showed on the DR system and the angles between the coronal plane of the body and the vertical plane of the flat panel detector (FPD) during taking these radiographs were recorded.The C-arm fluoroscopy unit was used to take the axial and tangential views referencing the angles measured on the DR system.Routine anteroposterior radiographs of the AC joint were taken on the volunteers.The minimal distances from the distal clavicle to the acromion were measured on both tangential and anteroposterior radiographs.The data was statistically analyzed.Results The clear axial and tangential radiographs of AC joints of the volunteers were obtained using both DR and C-arm fluoroscopy units.The angles demonstrated on the DR window are (20.8±2.4)° for male and (18.3±2.3)° for female.During taking the axial views,the angles between the coronal plane of the body and vertical plane of FPD are (23.3±3.2)° for male and (20.1±2.4)° for female.During taking tangential views,the corresponding angles are (117.5±3.7)° for male and (113.1±3.3)° for female.On the tangential

  16. Acute septic arthritis of the acromioclavicular joint caused by Haemophilus parainfluenzae: a rare causative origin.

    Hong, Myong-Joo; Kim, Yeon-Dong; Ham, Hyang-Do

    2015-04-01

    Septic arthritis of the acromioclavicular (AC) joint is a rare entity with symptoms that include erythema, swelling, and tenderness over the AC joint, fever, and limitation of shoulder motion with pain. In previous reports, Staphylococcus and Streptococcus species have been mentioned as common causative organisms. Haemophilus parainfluenzae is a normal inhabitant of the oral cavity, respiratory tract, gastrointestinal tract, and urogenital tract. However, it sometimes causes opportunistic infections leading to septic arthritis and osteomyelitis. AC joint infection associated with H.parainfluenzae is very rare, and only one case has been reported in the literature. Moreover, septic arthritis in immunocompetent patients is also very rare. Here, we report the case of a healthy patient with H. parainfluenzae-related septic arthritis of the AC joint. PMID:24584486

  17. Bioabsorbable Suture Anchor Migration to the Acromioclavicular Joint: How Far Can These Implants Go?

    Giovanna Medina

    2014-01-01

    Full Text Available Few complications regarding the use of bioabsorbable suture anchors in the shoulder have been reported. What motivated this case report was the unusual location of the anchor, found in the acromioclavicular joint which, to our knowledge, has never been reported so far. A 53-year old male with previous rotator cuff (RC repair using bioabsorbable suture anchors presented with pain and weakness after 2 years of surgery. A suspicion of retear of the RC led to request of a magnetic resonance image, in which the implant was found located in the acromioclavicular joint. The complications reported with the use of metallic implants around the shoulder led to the development of bioabsorbable anchors. Advantages are their absorption over time, minimizing the risk of migration or interference with revision surgery, less artifacts with magnetic resonance imaging, and tendon-to-bone repair strength similar to metallic anchors. Since the use of bioabsorbable suture anchors is increasing, it is important to know the possible complications associated with these devices.

  18. ISAKOS upper extremity committee consensus statement on the need for diversification of the Rockwood classification for acromioclavicular joint injuries

    Beitzel, Knut; Mazzocca, Augustus D; Bak, Klaus;

    2014-01-01

    Optimal treatment for the unstable acromioclavicular (AC) joint remains a highly debated topic in the field of orthopaedic medicine. In particular, no consensus exists regarding treatment of grade III injuries, which are classified according to the Rockwood classification by disruption of both th...

  19. Via de acesso cirúrgico posterossuperior para o tratamento das luxações acromioclaviculares: resultados de 84 casos operados Posterosuperior surgical access route for treatment of acromioclavicular dislocations: results from 84 surgical cases

    Danilo Canesin Dal Molin

    2012-10-01

    Full Text Available OBJETIVO: Avaliar os resultados do tratamento cirúrgico de 84 luxações acromioclaviculares agudas com a utilização da via de acesso posterossuperior do ombro. MÉTODOS: Foram avaliados 84 casos de luxações acromioclaviculares agudas grau III da classificação de Allman-Tossy operados de novembro de 2002 a maio de 2010. A média de idade dos pacientes foi de 34 anos. O diagnóstico foi realizado por avaliação clínica e radiográfica. Os pacientes foram operados pela mesma equipe cirúrgica em até três semanas da data do trauma realizando-se a via de acesso posterossuperior do ombro com acesso ao topo da base do processo coracoide para colocação de duas âncoras utilizadas na redução da luxação. O seguimento mínimo foi de 12 meses. A avaliação clínica-radiográfica pós-operatória foi realizada pelos critérios de Karlsson modificados e do escore da Universidade da Califórnia em Los Angeles (UCLA. RESULTADOS: Dos 84 pacientes operados, 92,8% apresentavam resultados bons ou excelentes e 7,2% de resultados regulares ou fracos pelo escore de avaliação da UCLA. Pelos critérios de Karlsson modificados 76,2% foram avaliados como grau A, 17,9% como grau B e 5,9% como grau C. CONCLUSÃO: A VIA de acesso posterossuperior do ombro é uma nova opção para acesso ao processo coracoide e tratamento das luxações acromioclaviculares, com resultados clínicos e radiográficos equivalentes aos da literatura.OBJECTIVE: To evaluate the results from surgical treatment of 84 cases of acute acromioclavicular dislocation, using a posterosuperior access route. METHODS: Eighty-four cases of acute acromioclavicular dislocation (grade III in the Allman-Tossy classification operated between November 2002 and May 2010 were evaluated. The patients' mean age was 34 years. The diagnoses were made using clinical and radiographic evaluations. The patients were operated by the same surgical team, within three weeks of the date of the trauma, using a

  20. Bipolar dislocation of the clavicle

    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.

  1. Bipolar dislocation of the clavicle.

    Jiang, Wei; Gao, Shu-Guang; Li, Yu-Sheng; Lei, Guang-Hua

    2012-11-01

    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. PMID:23325981

  2. Acromioclavicular joint acceleration-deceleration injury as a cause of persistent shoulder pain: Outcome after arthroscopic resection

    Ehud Atoun; Artan-Athanasios Bano; Alexander Van Tongel; Ali Narvani; Giuseppe Sforza; Ofer Levy

    2014-01-01

    Background: Shoulder pain in general and acromioclavicular joint (ACJ) pain specifically is common after acceleration-deceleration injury following road traffic accident (RTA). The outcome of surgical treatment in this condition is not described in the literature. The aim of the present study was to report the outcome of arthroscopic resection of the ACJ in these cases. Materials and Methods: Nine patients with localized ACJ pain, resistant to nonoperative treatment were referred on an a...

  3. Clinics in diagnostic imaging (151). Acromioclavicular joint geyser sign with chronic full-thickness supraspinatus tendon (SST) tear.

    Khor, Andrew Yu Keat; Wong, Steven Bak Siew

    2014-01-01

    An 82-year-old man presented with neck pain, right upper limb radiculopathy and right shoulder pain. Physical examination revealed a soft lump over the right shoulder joint, as well as reduced range of shoulder movements. On magnetic resonance imaging, the soft lump was shown to be a cystic mass over the acromioclavicular joint and was related to a full-thickness supraspinatus tendon tear. This is the classic geyser sign. The pathophysiology and clinical features of the geyser sign, and its i...

  4. Arthroscopic resection of the distal clavicle in osteoarthritis of the acromioclavicular joint

    Park, Tae-Soo; Lee, Kwang-Won

    2016-01-01

    Background: Symptomatic acromioclavicular joint (ACJ) lesions are a common cause of shoulder complaints that can be treated successfully with both conservative and surgical methods. There are several operative techniques, including both open and arthroscopic surgery, for excising the distal end of the clavicle. Here, we present a new modified arthroscopic technique for painful osteoarthritis of the ACJ and evaluate its clinical outcomes. Our hypothesis was that 4- to 7-mm resection of the distal clavicle in an en bloc fashion would have several advantages, including no bony remnants, maintenance of stability of the ACJ, and reduced prevalence of heterotopic ossification, in addition to elimination of the pathologic portion of the distal clavicle. Materials and Methods: 20 shoulders of 20 consecutive patients with painful and isolated osteoarthritis of the ACJ who were treated by arthroscopic en bloc resection of the distal clavicle were included in the study. There were 10 males and 10 females with an average age of 56 years (range 42–70 years). The mean duration of followup was 6 years and 2 months (range 4–8 years 10 months). The results were evaluated using the University of California Los Angeles (UCLA) shoulder rating score. Results: The overall UCLA score was 13.7 preoperatively, which improved to 33.4 postoperatively. All subscores were improved significantly (P painful osteoarthritis of the ACJ lesions in active patients engaged in overhead throwing sports and heavy labor. PMID:27512219

  5. Surgical Treatment Experience of Patients With Acromioclavicular Dislocation%肩锁关节脱位患者的手术治疗体会

    王凤彦

    2015-01-01

    目的:对肩锁关节脱位患者的手术治疗方法以及效果进行分析,并对手术治疗体会进行总结。方法选取于2013年11月~2014年8月期间在我院接受治疗的35例肩锁关节脱位患者,并对所有患者进行手术治疗,对手术方法和效果进行总结。结果按照Karlsson评价标准来评定术后疗效,优27例,占比77.1%,良5例,占比14.3%,差3例,占比8.6%,则本次研究的优良率为91.4%。结论对肩锁关节脱位患者采用手术治疗具有十分显著的临床效果,并且具有固定可靠、减少疼痛、防止肩部畸形以及获得较好的肩关节功能等诸多优点。%Objective To analyze surgical treatment method and its effect of patients with acromioclavicular dislocation and then summarize its surgical treatment experience.Methods Choose 35 patients with acromioclavicular dislocation who are received and treated in hospital from November 2013 to August 2014 and have them cured with surgical treatment and then make a summary of treatment experience.ResultsMake an evaluation on surgery treatment effect according to Karlsson standard, the result shows that 27 cases of performance are excellent, accounting 77.1%; 5 cases of performance are good, accounting 14.3%; and 3 cases of performance are bad, accounting 8.6%, the treatment excellence rate is up to 91.4%. Conclusion Surgical treatment is of efifcacy in treatment of patients with acromioclavicular dislocation; and such a treatment method has advantages of reliable fixation and pain alleviation, prevention form shoulder deformation and improvement of shoulder function; thus, surgical treatment is quite worthwhile to be promoted and applied clinically in treatment of acromioclavicular dislocation.

  6. Surgical treatment of acromioclavicular dislocation with coracoclavicular screw and double Endobutton plate%喙锁螺钉与双Endobutton钢板治疗肩锁关节脱位的临床研究

    杨杰; 赵友明; 孙辽军; 洪建军; 孔建中; 杨雷; 窦海成; 邵荣学

    2011-01-01

    Objective To evaluate and compare the clinical outcome of coracoclavicular screw and double Endobutton plate in treatment of acromioclavicular dislocation ( Rockwood Ⅲ-Ⅴ ). Methods Twenty-eight patients with Rockwood Ⅲ-Ⅴ acromioclavicular dislocation were subjected to surgical reconstruction from January 2008 to October 2009. The coracoclavicular screw was performed in 14 patients and the double Endobutton plate in the other 14 patients. Clinical evaluation was performed by using Constant score and subject should value (SSV) in both groups, and the preoperative and postoperative radiographs, curative effects and complications were compared. Results The patients in two groups were followed up for a range of 6-25 months (average 12.6 months) , which showed higher postoperative Constant score and SSV score than preoperation in both groups (P<0.05). But the postoperative Constant sore and postoperative SSV score in the double Endobutton group were (89.8 ±8.3) points and (85.7 ±7. 3) points respectively, significantly better than (78. 0 ± 10. 3) points and (71. 8 ±9. 7) points respectively in the coracoclavicular screw group ( P < 0.05). The radiologic measurement showed no significant difference in regard of the coracoclavicular distance three months after operation in two groups (P>0.05). Conclusions The double Endobutton plate can attain significantly superior clinical outcomes for Rockwood Ⅲ-Ⅴ acromioclavicular dislocation compared with the coracoclavicular screw. The surgical technique of reconstructing the coracoclavicular ligament through anatomical approach will be the future trend in treatment of the acromioclavicular joint dislocation.%目的 探讨喙锁螺钉与双Endobutton钢板治疗Rockwocd Ⅲ~Ⅴ型肩锁关节脱位的临床疗效,并对两者进行对比研究.方法自2008年1月至2009年10月收治Rockwood Ⅲ~Ⅴ型肩锁关节脱位患者28例,电脑随机抽样分为两组,14例采用喙锁螺钉治疗,另14例采用

  7. Dislocations

    Dislocations are joint injuries that force the ends of your bones out of position. The cause is often a fall or a blow, sometimes from playing a contact sport. You can dislocate your ankles, knees, shoulders, hips, elbows and jaw. You can also dislocate your finger and toe joints. Dislocated joints often ...

  8. Locked volar distal radioulnar joint dislocation

    Bouri, Fadi; Fuad, Mazhar; Elsayed Abdolenour, Ayman

    2016-01-01

    Introduction Volar dislocation of the distal radioulnar joint is a rare injury which is commonly missed in the emergency departments. A thorough review of literature showed very few reported cases and the cause for irreducibility varied in different cases, Lack of suspicion and improper X-ray can delay the diagnosis. Case presentation Our article discusses a case 40 year old construction worker, who presented to the Emergency with work-related injury, complaining of left wrist pain, deformity and inability to rotate his forearm. X-rays revealed a volar dislocation of distal ulna which was reducible after manipulation under General Anesthesia (GA). The joint was stable after the reduction. Discussion Isolated dislocation of the distal radioulnar joint can be either volar or dorsal, although dorsal dislocation is more common. The distal radioulnar articulation plays an important role in the rotational movement of the forearm. It allows pronation and supination which are essential for the function of the upper limb. Pronator Quadratus muscle spasm is an important blockade to reduction and was preventing reduction in this case. Methods The work has been reported in line with the CARE criteria [9]. Conclusion Volar locked dislocation of Distal Radio ulnar joint is a rare injury. High degree of clinical suspicion and proper X-ray is required for prompt detection. The importance of this case is to raise the awareness among physicians in treating these kind of injuries by careful assessment of the patient and radiographs, and to consider pronator quadratus as an important cause for the blockade to reduction. PMID:27016647

  9. 应用不同手术方法治疗陈旧性肩锁关节脱位的疗效分析%Review of the results of different operative procedures for old acromioclavicular dislocation

    吴其常; 卞传华; 苗旭漫

    2001-01-01

    目的比较分析应用不同手术方法治疗陈旧性肩锁关节脱位的疗效。方法对43例陈旧性肩锁关节脱位患者分别应用单纯切开复位克氏针内固定(9例);切开复位内固定并肩锁关节韧带重建(14例);切开复位内固定并喙突上移(20例)三种手术方法进行治疗,术后平均随访4.8年,对其自觉症状、上肢肌力、肩关节功能和肩锁关节间隙等改善程度进行比较。结果三种术式的优良率分别为33%(3/9)、50%(7/14)和74%(15/20)。单纯切开复位克氏针内固定法的疗效与切开复位内固定并肩锁韧带重建法相比,差异无显著性意义(P>0.05),两者与切开复位内固定并喙突上移法比较,差异有显著性意义(均P 0.05). Modified Dewar's operation was better compared with Kirschner wire fixation and reconstruction of acromioclavicular ligament (P< 0.05). Conclusion A satisfactory surgical procedure for treatment of old acromioclavicular dislocation should accomplish the following points: removal of scar tissue and intra articular cartilaginous fragments, reconstruction of joint stability and effective internal fixation until complete healing of the ligament structures.

  10. Dislocation of the proximal tibiofibular joint

    Milankov Miroslav

    2013-01-01

    Full Text Available Introduction. Dislocation of the proximal tibiofibular joint is a rare injury. It occurs during a sports activity that includes rough twisting movements of the bent knee. The role of the proximal tibiofibular joint is to reduce torsional loads to the ankle, to distribute the bending moment of the outer side of tibia, and transfer the vertical load while standing. In the literature there is no larger series; only several cases of the proximal tibiofibular joint dislocation treated by different methods have been published so far. Case Report. A 23-year-old male soccer player sustained an injury after he had joined the game without previous warming-up. He fell on his right side because of a sudden change of direction while his foot was fixed to the base. He felt a severe pain and had a sensation as if something had snapped in his right knee. Pain and swelling at the head of fibula were found by physical examination, which, however, did not reveal any pain, swelling and instability of the ankle or peroneal nerve palsy. The x-ray showed anterolateral dislocation of the proximal tibiofibular joint, Ogden type II. Since manual reposition in general anesthesia failed, open reduction internal fixation was performed and proximal tibiofibular joint was transfixed with a screw. After the wound closure, the above-the-knee plaster cast was applied. The screw was extracted six weeks later, full weight bearing was allowed and he started with physical therapy. Four months after the injury he returned to sports activities. On the follow- up one year after the injury he had the full range of motion of the knee, no complains, and continued with active soccer playing. X-ray showed no signs of arthrosis of the proximal tibiofibular joint. Conclusion. The proximal tibiofibular joint dislocation may be the cause of the chronic pain of the knee so it has to be taken into account when making differential diagnosis in case of the pain at the lateral side of the knee. The

  11. Help Desk Answers: Surgery vs conservative management for AC joint repair: How do the 2 compare?

    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. PMID:27262254

  12. Parasymphyseal fracture with an associated temporomandibular joint dislocation: case report.

    Pynn, B R; Clarke, H M

    1992-02-01

    A case of traumatic mandibular fracture with associated unilateral anterior dislocation of the temporomandibular joint in a child is described. Although anterior dislocation is common, this combination of fracture and separate dislocation to our knowledge has not been reported in a young child. The unusual management required in this case is discussed. PMID:1740810

  13. Dislocation

    ... Alternative Names Joint dislocation Images Radial head injury Dislocation of the hip Shoulder joint References Boss SE, Mehta A, Maddow C, ... Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also ... Browse the Encyclopedia A.D.A.M., Inc. ...

  14. In-game Management of Common Joint Dislocations

    Skelley, Nathan W.; McCormick, Jeremy J; Smith, Matthew V.

    2014-01-01

    Context: Sideline management of sports-related joint dislocations often places the treating medical professional in a challenging position. These injuries frequently require prompt evaluation, diagnosis, reduction, and postreduction management before they can be evaluated at a medical facility. Our objective is to review the mechanism, evaluation, reduction, and postreduction management of sports-related dislocations to the shoulder, elbow, finger, knee, patella, and ankle joints. Evidence Ac...

  15. The morphologic and radiologic evaluation of the acromioclavicular joint in healthy individuals

    Yucel, Mustafa

    2004-01-01

    The topographic and functional anatomy and the age depended osteoarthrosis of the right acromioclaviculer joint has been examined on 39 dead bodies by means of anatomopathologic and radiologic tools. The AC joints have been extirpated in to, fixed in formalin and pinned in the horizontal plane; they have been arthrotomizedn and the macroscopic view of the joint surface photographed. Subsequently, the joint surfaces have been lamellized in the frontal plane, and decalcified; three different h...

  16. 锁骨钩钢板治疗Rockwood Ⅲ型肩锁关节脱位的治疗分析%Study of treatment of Rockwood type Ⅲ acromioclavicular dislocation with Hook plate

    郭丹; 周海斌

    2012-01-01

    [Objective] To analyze shoulder pain and restricted movement after treatment with Hook plate about Rockwood type HI acromioclavicular dislocation patients. [Method] From February ,2008 to February,2011,35 Rockwood type Ⅲ acromioclavicular dislocation patients (23 male and 12 female,average age 42.4) were treated in our hospital. They were treated with Hook plate. Adjusted Constant-Murley score was used to evaluate shoulder function. The Average follow-up time were 13.5 months. [Result]In Rockwood type Ⅲ acromioclavicular dislocation,there were 11 cases with different grade shoulder pain and restricted movement in the 19 patients. The score difference was significant ( P < 0.05 ). [ Conclusion ] Rockwood type Ⅲ acromioclavicular dislocation,treated with Hook plate leads to high rate of shoulder pain and restricted movement,which is not beneficial to functional rehabilitation.%[目的]探讨Rockwood Ⅲ型肩锁关节脱位行锁骨钩钢板手术治疗后肩关节疼痛、活动受限的原因.[方法]苏北人民医院和苏州大学附属第二医院自2008年2月~2011年2月共35例Rockwood Ⅲ型肩锁关节脱位病人,无骨折、神经损伤及血管损伤等其他合并伤,其中,男23例,女12例,平均42.4岁,行锁骨钩钢板手术治疗,术后按调整的Constant-Murley随访观察各病例肩关节恢复情况,平均随访13.5个月.[结果]35例Rockwood Ⅲ型肩锁关节脱位行锁骨钩钢板手术治疗中,有11例出现不同程度的肩关节肩痛、活动受限的症状,统计检验无肩痛、活动受限症状病例与有肩痛、活动受限症状病例之间评分差异有统计学意义(P<0.05).[结论]Rockwood Ⅲ型肩锁关节脱位行锁骨钩钢板手术治疗术后易出现肩痛、活动受限的症状,会明显影响肩关节功能恢复.

  17. Posterior dislocation of the shoulder joint

    Thakker Tejas

    2006-01-01

    Full Text Available Background: Posterior dislocation of shoulder is a rather uncommon injury that is often not diagnosed at the initial examination. However certain constant clinical signs may lead the examiner to suspect the presence of this condition. Even the routine antero-posterior roentgenogram may provide a few clues to diagnosis but the axillary view is mandatory to verify diagnosis. Material and methods : We report a series of 15 shoulders (14 patients with a locked posterior dislocation. Electric shock (7 patients, vehicular accident (4 patients and epileptic seizure (3 patients was causes of dislocation in these patients. The diagnosis was missed initially in 10 cases. An axillary radiograph confirmed the diagnosis in all. Treatment consisted of closed reduction, which was successful in 5, Neer′s modification of McLaughlin procedure (transfer of subscapularis in 6, hemireplacement arthroplasty in one shoulder and tuberosity fixation in one patient. Results : Follow-up ranged from 1 year to 4 years. Five patients had excellent, five good, two poor and one had fair result. Conclusion : Key to diagnosis is a high index of suspicion. The prognosis became less favorable and the therapeutic difficulties were found to be increased in direct proportion to the length of time, these lesions remain undiagnosed. With early recognisition of dislocation, prompt reduction is relatively easy. Surgical intervention is necessary for old unreduced posterior dislocations.

  18. Cervical facet joint kinematics during bilateral facet dislocation

    Panjabi, Manohar M.; Simpson, Andrew K.; Ivancic, Paul C.; Pearson, Adam M.; Tominaga, Yasuhiro; Yue, James J.

    2007-01-01

    Previous biomechanical models of cervical bilateral facet dislocation (BFD) are limited to quasi-static loading or manual ligament transection. The goal of the present study was to determine the facet joint kinematics during high-speed BFD. Dislocation was simulated using ten cervical functional spinal units with muscle force replication by frontal impact of the lower vertebra, tilted posteriorly by 42.5°. Average peak rotations and anterior sliding (displacement of upper articulating facet s...

  19. CONGENITAL DISLOCATION OF RIGHT HIP JOINT: IMPORTANCE OF DYNAMIC ASSESSMENT

    Pranita viveki; R. G. Viveki

    2014-01-01

    Congenital Dislocation of Hip (CDH), is one of the most common congenital diseases in the orthopedic field. It is also known as Developmental Dysplasia of Hip. The condition can be diagnosed by clinical, ultrasonographic and radiological examination. Here we are reporting two days old male baby with congenital dislocation of right hip joint. The goal of treatment is to obtain a reduction to provide an optimal environment for femoral head and acetabular development. Early diagnosis is the mo...

  20. Inferior glenohumeral joint dislocation with greater tuberosity avulsion

    Mohd Faizan; Latif Zafar Jilani; Mazhar Abbas; Yasir Salam Siddiqui; Aamir Bin Sabir; M.K.A.Sherwani; Saifullah Khalid

    2015-01-01

    Inferior glenohumeral dislocation is the least common type of glenohumeral dislocations.It may be associated with fractures of the adjacent bones and neurovascular compromise.It should be treated immediately by close reduction.The associated neuropraxia usually recovers with time.Traction-counter traction method is commonly used for reduction followed by immobilization of the shoulder for three weeks.Here,we report a case of inferior glenohumeral joint dislocation with greater tuberosity fracture with transient neurovascular compromise and present a brief review of the literature.

  1. Titanium Cable Bundling in Treatment of Acromioclavicular Dislocation%钛缆捆扎治疗肩锁关节脱位

    吴冬灵; 刘中国; 余跃伟

    2015-01-01

    Objective To investigate the effect of titanium cable in the treatment of the dislocation of the shoulder joint.Methods 28 cases of patients with dislocation of the shoulder joint were treated,and the clinical data were retrospectively analyzed.Results Al patients were folowed up for 3 to 12 months,and al the patients were folowed up for anatomic reduction. The average constant score was 91.4 points at the end of folow-up.Conclusion The use of titanium cable in the treatment of shoulder joint dislocation is significant.%目的:探讨钛缆捆扎治疗肩锁关节脱位的疗效。方法收集28例肩锁关节脱位患者进行治疗,并回顾性分析其临床资料。结果重建后随访3~12个月,所有患者术中、术后锁骨远端高度均达到解剖复位。终末随访时,平均Constant 评分为91.4分。结论采用钛缆捆扎治疗肩锁关节脱位疗效理想。

  2. Spontaneous atraumatic dislocation of sternoclavicular joint in Reiter's syndrome

    Vijay Kumar Digge; Sanjay Meena; Sheh Alam Khan; Ravi Mittal

    2012-01-01

    Reactive arthritis or Reiter's syndrome characteristically affects the joint of the lower limb in an asymmetrical pattern.Usually it does not affect the axial skeleton or upper limbs.Although cases of atraumatic atlantoaxial subluxations have been reported,no case of spontaneous sternoclavicular dislocation in Reiter's syndrome has been reported.This paper describes a case of a 26 year old male patient who developed a spontaneous posterior sternoclavicular joint dislocation.No attempt of reduction was made and the patient was managed conservatively with good results.

  3. CONGENITAL DISLOCATION OF RIGHT HIP JOINT: IMPORTANCE OF DYNAMIC ASSESSMENT

    Pranita viveki

    2014-11-01

    Full Text Available Congenital Dislocation of Hip (CDH, is one of the most common congenital diseases in the orthopedic field. It is also known as Developmental Dysplasia of Hip. The condition can be diagnosed by clinical, ultrasonographic and radiological examination. Here we are reporting two days old male baby with congenital dislocation of right hip joint. The goal of treatment is to obtain a reduction to provide an optimal environment for femoral head and acetabular development. Early diagnosis is the most crucial aspect of the treatment of children with congenital dislocation of hip. If dislocation remains undiagnosed or neglected, the secondary pathological changes take place. Education of primary care colleagues, in making the diagnosis and prompt referral for management is recommended.

  4. Systematics of glenohumoral and acromioclavicular arthritis

    A common risk factor for osteoarthritis (OA) of the glenohumeral joint is instability and is often observed as a sequel to dislocation. Altered biomechanics will ultimately result in joint degeneration including osteophyte development at the lower margin of the humerus, glenoidal cartilage loss and surface deformity. An OA of the glenohumeral joint is often coexistent with soft tissue derangement of the shoulder. In advanced stages defects of the rotator cuff and OA of the glenohumeral joint may accelerate disease progression. Degenerative changes of the acromioclavicular joint (AC joint) are commonly seen in older persons with only modest correlation with clinical symptoms. Symptomatic OA of the AC joint is often concomitantly observed with degenerative changes of the glenohumeral joint. Standard radiographs are the basis of a structural assessment of shoulder OA but lack correlation with clinical symptoms and are insensitive for the detection of early degenerative changes. Magnetic resonance imaging (MRI) provides increased sensitivity for the detection of cartilage defects and reveals relevant soft tissue changes, such as lesions of the glenoid labrum and capsuloligamentous structures, which are seen in conjunction with instability. It is also the method of choice to detect clinically relevant bone marrow edema-like lesions or synovial changes that are associated with symptomatic OA. Standard radiographs are not applicable for detection of early degenerative changes. Once OA is suspected clinically, MRI is the method of choice for further structural assessment. The administration of an intravenous contrast agent is useful for assessing synovitis, which commonly correlates with clinical disease manifestations. For preoperative and surgical planning of joint replacement, MRI or CT should be used. (orig.)

  5. Dorsal dislocation of the trapezoid at the scaphotrapeziotrapezoidal joint.

    Ricciardi, Benjamin F; Malliaris, Stephanie; Weiland, Andrew J

    2015-05-01

    Background Axial dislocations of the trapezoid are rare, high-energy injuries. We present an unusual case of isolated dorsal dislocation of the trapezoid and index metacarpal at the scaphotrapeziotrapezoidal (STT) joint due to steering wheel injury. Case Description A 56-year-old man presented to our office with right hand pain for 10 days after a head-on motor vehicle accident (MVA) in which he suffered an axial load injury to his hand on the steering wheel. X-ray images were reported as unremarkable. Further workup with computed tomography (CT) scan revealed an isolated dorsal dislocation of the trapezoid with its associated index metacarpal at the STT joint. The patient was treated with open reduction, pinning, and dorsal capsulodesis. Literature Review Dorsal dislocation of the trapezoid has been associated with high-energy trauma such as industrial accidents or motorcycle accidents; however, recent case reports have also revealed an axial loading mechanism from a steering wheel injury as an increasingly common mechanism. These cases typically occur concomitantly with other fractures or dislocations of the carpal bones or carpometacarpal (CMC) joints. Multiple reports of delayed diagnoses due to distracting injuries and difficulty of recognition on plain radiographs have been reported. Clinical Relevance Dorsal dislocation of the trapezoid with its associated second metacarpal is a rare, high-energy injury that can often be missed on plain radiography. We report a rare variant with no concomitant injury to the metacarpals or carpal bones. A low index of suspicion for further imaging should exist in the setting of an axial loading injury to the hand. PMID:25945300

  6. Recurrent Dislocation of the Shoulder Joint

    Brand, Richard A.

    2008-01-01

    Dr. Anthony F. DePalma is shown. Photograph provided with kind permission of the Art Committee of Thomas Jefferson University, Philadelphia, PA. Dr. DePalma was the first editor of Clinical Orthopaedics and Related Research, established by the recently formed Association of Bone and Joint Surgeons. The idea of forming the Association of Bone and Joint surgeons had been conceived by Dr. Earl McBride of Oklahoma City in 1947, and organized by a group of twelve individuals (Drs. Earl McBride, Ga...

  7. A comparison of two treatments of Rockwood type Ⅲ acromioclavicular dislocation%Rockwood Ⅲ型肩锁关节脱位两种治疗方法分析

    郭丹; 周海斌

    2013-01-01

    目的 探讨Rockwood Ⅲ型肩锁关节脱位手术及保守两种方法治疗后效果及对肩关节功能恢复的影响.方法 苏北人民医院和苏州大学附属第二医院骨科自2008年2月-2010年2月66例Rockwood Ⅲ型肩锁关节脱位病人,其中女性29例,男性37例,平均41.6岁,分锁骨钩钢板手术治疗和背带式锁骨固定带保守治疗,按调整的Constant-Murley评分系统随访观察各病例肩关节恢复情况.结果 Rockwood Ⅲ型肩锁关节脱位中,35例锁骨钩钢板手术治疗病例中3例出现肩关节活动受限、肩痛症状,背带式锁骨固定带保守治疗组31例病人中3例出现肩关节活动受限、肩痛症状,统计检验手术治疗组与保守治疗组之间评分差异无统计学意义(P>0.05).结论 Rockwood Ⅲ型肩锁关节脱位手术治疗与保守治疗对功能恢复影响差异不明显.%Objective To evaluate two treatment methods in Rockwood type Ⅲ acromioclavicular dislocation patients,and to evaluate the influence of trement methods on shoulder function. Methods From February,2008 to February,2010,66 Rockwood type Ⅲ acromioclavicular dislocation patients( 37 male and 29 female,average age 41. 6 )were treated in the Northern Jiangsu People' s Hospital and the Second Affiliated Hospital of Soochow University, with operation used hook plate and conservative treatment by clavicle sling immobilization respectively. Adjusted Constant-Murley Scale was used to evaluate shoulder function. Results In Rockwood type Ⅲ acromioclavicular dislocation. There were 3 cases with shoulder painful and restricted symptoms in the 35 patients treated with operation. There were 3 cases with shoulder painful and restricted symptoms in the 31 patients treated with conservative treatment patients. The difference between operation and conservative treatment was not significant P >0.05 ). Conclusion In Rockwood type Ⅲ acromioclavicular dislocation,for operation and conservative treatment,we could not

  8. Isolated Dislocation of Proximal Tibiofibular Joint

    Oktay, Alper; Baysal, Ozgur; Ecevız, Engin; Elmalı, Nurzat

    2014-01-01

    Objectives: Proximal tibiofibular joint luxation is very rare condition and usually missed in the ED. The aim of the study is if a patient is brought to ED with knee injury, we should keep in mind this pathology. Methods: A 23 year old man was admitted to emergency department with knee pain and restricted movement of the knee during the football match. Physical examination revealed mild swelling and limited ROM on his knee. We took AP and lateral X-rays immediately. We diagnosed the proximal ...

  9. Imaging features of traumatic dislocation of the lumbosacral joint associated with disc herniation

    Tohme-Noun, C.; Krainik, A.; Menu, Y. [Department of Radiology, Hopital Beaujon, AP HP, Universite Paris 7, Faculte de Medecine Bichat-Beaujon, Paris (France); Rillardon, L.; Guigui, P. [Department of Orthopedic Surgery, Hopital Beaujon, AP HP, Universite Paris 7, Faculte de Medecine Bichat-Beaujon, Paris (France); Feydy, A. [Department of Radiology, Hopital Beaujon, AP HP, Universite Paris 7, Faculte de Medecine Bichat-Beaujon, Paris (France); Department of Radiology, Hopital Beaujon, 100 avenue du General Leclerc, 92118, Clichy (France)

    2003-06-01

    Bilateral facet dislocation of the lumbosacral joint is an uncommon injury. We report on the imaging findings in a patient who had an acute disc herniation associated with a bilateral traumatic lumbosacral dislocation. (orig.)

  10. Imaging features of traumatic dislocation of the lumbosacral joint associated with disc herniation

    Bilateral facet dislocation of the lumbosacral joint is an uncommon injury. We report on the imaging findings in a patient who had an acute disc herniation associated with a bilateral traumatic lumbosacral dislocation. (orig.)

  11. Bilateral temporomandibular joint dislocation in a 29-year-old man: a case report

    Thangarajah Tanujan

    2010-08-01

    Full Text Available Abstract Introduction A dislocation of the temporomandibular joint represents three percent of all reported dislocated joints. The treatment entails reduction of the deformity and this can often be achieved in a ward setting. Case presentation We present the case of a 29-year-old Caucasian man with a non-traumatic bilateral anterior temporomandibular joint dislocation. Following several unsuccessful attempts, due to both inadequate patient analgesia and sedation, joint reduction had to be performed in theatre with the patient under general anesthesia. Conclusion This case highlights the importance of providing the patient with adequate analgesia and sedation when attempting the reduction of temporomandibular joint dislocations.

  12. POSTERIOR STERNOCLAVICULAR JOINT DISLOCATION IN A DIVISION I FOOTBALL PLAYER: A CASE REPORT

    Cruz, Mario F.; Erdeljac, Joe; Williams, Richard(Institut für Theoretische Physik, Justus-Liebig–Universität Giessen, 35392 Giessen, Germany); Brown, Mike; Bolgla, Lori

    2015-01-01

    Posterior dislocation of the sterno‐clavicular (SC) joint is a rare injury in athletes. It normally occurs in high collision sports such as American football or rugby. Acute posterior dislocations of the SC joint can be life‐threatening as the posteriorly displaced clavicle can cause damage to vital vascular and respiratory structures such as the aortic arch, the carotid and subclavian arteries, and the trachea. The potential severity of a posterior SC joint dislocation provides multiple chal...

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

    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.

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

    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. PMID:8572795

  15. Simultaneous Dislocation of Radiocapitellar and Distal Radioulnar Joint

    Tomio Nishi; Noriyuki Suzuki; Takayuki Tani; Hiroshi Aonuma

    2013-01-01

    A 45-year-old male presented to the emergency room of our institution complaining of severe pain around the left elbow. While playing volleyball, he slipped down with his left arm hit between the floor and his body. He complaind of strong pain from left elbow to hand, and active motion of elbow and wrist joint was impossible. His forearm was held in supinated position. On X-ray examination, radius head was deviated to anterior lateral side, and distal end of radius was dislocated to dorsal si...

  16. Acromioclavicular joint reconstruction using a tendon graft: a biomechanical study comparing a novel “sutured throughout” tendon graft to a standard tendon graft

    Naziri Qais

    2016-01-01

    Full Text Available Background: With a recurrence rate of over 30%, techniques that offer stronger acromioclavicular (AC joint reconstruction through increased graft strength may provide longevity. The purpose of our study was to determine the biomechanical strength of a novel tendon graft sutured throughout compared to a native tendon graft in Grade 3 anatomical AC joint reconstruction. Methods: For this in vitro experiment, nine paired (n = 18 embalmed cadaveric AC joints of three males and six females (age 86 years, range 51–94 years were harvested. Anatomic repair with fresh bovine Achilles tendon grafts without bone block was simulated. Specimens were divided into two groups; with group 1 using grafts with ultra-high molecular-weight polyethylene (UHMWPE suture ran throughout the entire length. In group 2, reconstruction with only native allografts was performed. The distal scapula and humerus were casted in epoxy compound and mounted on the mechanical testing machine. Tensile tests were performed using a mechanical testing machine at the rate of 50 mm/min. Maximum load and displacement to failure were collected. Results: The average load to failure was significantly higher for group 1 compared to group 2, with mean values of 437.5 N ± 160.7 N and 94.4 N ± 43.6 N, (p = 0.001. The average displacement to failure was not significantly different, with 29.7 mm ± 10.6 mm in group 1 and 25 mm ± 9.1 mm in group 2 (p = 0.25. Conclusion: We conclude that a UHMWPE suture reinforced graft can provide a 3.6 times stronger AC joint reconstruction compared to a native graft.

  17. Dorsal Buttress Plate Fixation of Ulnar Carpometacarpal Joint Fracture Dislocations.

    Tan, En Si; Chao, Tay Shian

    2016-06-01

    We propose a method for open reduction and internal fixation of early and unstable ulnar (fourth and/or fifth) carpometacarpal joint (CMCJ) fracture subluxations or dislocations using a dorsal buttress plate. In ulnar CMCJ fracture dislocations, the metacarpal has a tendency to displace dorsally and proximally when there is an axial load. Using the dorsal buttress plate method of fixation, a plate is fixed proximally to the hamate, aligned parallel and dorsal to the metacarpal to act as a buttress, to resist this movement. To preserve the fourth and the fifth CMCJ mobility, the distal end of the plate is not fixed to the metacarpal base. We illustrate the use of this technique on 4 patients who had different patterns of injury at the ulnar CMCJ. All patients regained excellent range of motion and function. None of the patients had redisplacement or nonunion of fracture. The dorsal buttress plate is a viable option for fixation of early and unstable ulnar CMCJ fracture subluxations or dislocations. PMID:27077465

  18. Simultaneous dislocation of radiocapitellar and distal radioulnar joint.

    Nishi, Tomio; Suzuki, Noriyuki; Tani, Takayuki; Aonuma, Hiroshi

    2013-01-01

    A 45-year-old male presented to the emergency room of our institution complaining of severe pain around the left elbow. While playing volleyball, he slipped down with his left arm hit between the floor and his body. He complaind of strong pain from left elbow to hand, and active motion of elbow and wrist joint was impossible. His forearm was held in supinated position. On X-ray examination, radius head was deviated to anterior lateral side, and distal end of radius was dislocated to dorsal side. Tenderness was prominent at the site of radial head and distal radioulnar joint. Surgical treatment was performed using triceps tendon strip. Good functional recovery was gained. PMID:24194995

  19. Simultaneous Dislocation of Radiocapitellar and Distal Radioulnar Joint

    Tomio Nishi

    2013-01-01

    Full Text Available A 45-year-old male presented to the emergency room of our institution complaining of severe pain around the left elbow. While playing volleyball, he slipped down with his left arm hit between the floor and his body. He complaind of strong pain from left elbow to hand, and active motion of elbow and wrist joint was impossible. His forearm was held in supinated position. On X-ray examination, radius head was deviated to anterior lateral side, and distal end of radius was dislocated to dorsal side. Tenderness was prominent at the site of radial head and distal radioulnar joint. Surgical treatment was performed using triceps tendon strip. Good functional recovery was gained.

  20. Compare of 3 different types of closed reduction and internal fixation for the fresh complete acromioclavicular dislocation%3种闭合复位内固定法治疗新鲜肩锁关节全脱位的疗效比较

    聂伟志; 谭远超; 杨茂清; 朱惠芳

    2011-01-01

    目的:比较3种闭合复位内固定法治疗新鲜肩锁关节全脱住的疗效.方法:136例新鲜肩锁关节全脱位患者,闭合复位后采用经皮"肩峰-锁骨"双枚钢针固定治疗31例(A组),采用经皮"肩峰-锁骨"双枚钢针固定+经皮缝合肩锁关节囊治疗45例(B组),采用经皮"肩峰一锁骨"双枚钢针固定+经皮"锁骨一喙突"空心螺钉固定+经皮缝合肩锁关节囊治疗60例(c组,"三联固定"组),参照Karlsson评价标准比较3组疗效.结果:3组疗效之间的差异有统计学意义(x2=21.623,P=0.002),C组疗效优于B组(u=2.014,P=0.002),B组疗效优于A组(u=2.781,P=0.006).结论:经皮"肩峰-锁骨"双枚钢针固定+经皮"锁骨-喙突"空心螺钉固定+经皮缝合肩锁关节囊治疗新鲜肩锁关节全脱位,疗效优于经皮"肩峰-锁骨"钢针固定+经皮缝合肩锁关节囊,更优于单纯"肩峰-锁骨"钢针固定.%Objective: To compare the curative effect of 3 different types of closed reduction and internal fixation on fresh complete acromioclavicular dislocation. Methods: 136 patients sustained complete acromioclavicular dislocation were divided into 3 groups. 31 cases in Group A were treated with acromioclavicular closed reduction and acromioclavicular internal fixation by 2 steel - wire per cutem. 45 cases in Group B were treated with acromioclavicular closed reduction and acromioclavicular internal fixation by 2 steel - wire per cutem and suturation of the capsula articularis acromioclavicularis per cutem. 60 cases in Group C were treated with acromioclavicular closed reduction and acromioclavicular internal fixation by 2 steel - wire per cutem and suturation of the capsula articularis acromioclavicularis per cutem and fixation with a hollowed screw between the clavicle and the coracoid (three point fixation). The curative effects were evaluated according to Karlsson' s standard. Results: There was statistical difference in the curative effects between the 3 groups(x2 = 21. 623

  1. Bilateral Anterior Fracture-Dislocation of Shoulder Joint- A rare case with Delayed Presentation

    Sunku, Nithin; Kalaiah, Kiran; Marulasidappa, G.; Gopinath, P

    2012-01-01

    Introduction: The shoulder is the most frequently dislocated joint. Bilateral glenohumeral dislocations are rare and almost always posterior. Bilateral anterior fracture dislocations of humeral neck in a patient with seizure are extremely rare. We report one such case of delayed presentation of bilateral anterior fracture dislocation of shoulder after an epileptic attack. Case Report: We describe a rare case of 30 year old gentleman who presented with first episode of seizure following alcoho...

  2. Dorsal traumatic dislocation of first and second metatarsophalangeal joint (A case study

    Baghery Fard A

    2001-11-01

    Full Text Available Dorsal traumatic dislocation of metatarsophalangeal joint of great toe is a rare injury. Ability to reduce the dislocation by nonoperative measures depends largely on the type of dislocation and involvement of the sesamoid complex. There are three basic types of dislocations. Type I cases are usually irreducible on closed reduction, the metatarsal head being incarcerated by the conjoined tendons with their intact sesamoids. In type II, the sesamoid complex disruption usually pemits closed reduction. We present an irreducible dislocation of the first metatarsophalangeal joint with fibular sesamoid fracture in an 80-year-old man. In addition, he had a concomitant dorsal dislocation of the second MTP of the same foot, to our knowledge only one case with this injury was reported in the literature.

  3. [Post-traumatic bipolar dislocation of the clavicle: is operative treatment reasonable?].

    Dudda, M; Kruppa, C; Schildhauer, T A

    2013-02-01

    Bipolar dislocation of the clavicle ("floating clavicle") is extremely rare. It exists no standardised treatment for this trauma and the treatment is often conservative. This is mainly an anterior displacement of the sternoclavicular joint (type III according to Allman) and a posterior dislocation of the acromioclavicular joint (type IV according to Rockwood).We report on a 60 year old male who fell onto the right shoulder. He sustained a 'floating clavicle' and had a massive dislocation, impairment of range of motion and pain. Venous congestion was observable. We stabilised the dislocated acromioclavicular joint with a Balser's plate, the sternoclavicular joint was fixed with PDS cord tension band technique around the first rip and the sternum. In addition we resected the anterior part of the distal clavicle to get a better cosmetic result. Post-operatively the patient had an excellent range of motion without any further symptoms after six weeks and one year. Venous congestion was not more observable.In most of the cases dislocations of both ends of the clavicle are treated conservatively. We recommend an operative treatment especially in young and active patients to avoid re-dislocation and to archive better cosmetic results. PMID:22367519

  4. Biepicondylar fracture dislocation of the elbow joint concomitant with ulnar nerve injury

    Konya, M Nuri; Aslan, Ahmet; Sofu, Hakan; Yıldırım, Timur

    2013-01-01

    In this article, we present a case of humeral biepicondylar fracture dislocation concomitant with ulnar nerve injury in a seventeen year-old male patient. Physical examination of our patient in the emergency room revealed a painful, edematous and deformed-looking left elbow joint. Hypoesthesia of the little finger was also diagnosed on the left hand. Radiological assessment ended up with a posterior fracture dislocation of the elbow joint accompanied by intra-articular loose bodies. Open redu...

  5. The Classic: A Dissertation Upon Dislocations and Fractures of the Clavicle and Shoulder-Joint

    Callaway, Thomas

    2011-01-01

    This Classic Article is a reprint of a section on scapula fractures in the original work by T. Callaway, Jr., A Dissertation Upon Dislocations and Fractures of the Clavicle and Shoulder-Joint. An accompanying biographical sketch of Thomas Callaway, Jr. is available at DOI 10.1007/s11999-011-2097-2. The Classic Article is ©1849 and is reprinted from Callaway T. A Dissertation Upon Dislocations and Fractures of the Clavicle and Shoulder-Joint. London: Samuel Highly; 1849.

  6. Dislocations

    Representations of main geometrical properties of dislocations, their interaction between each other and with a free surface are given. Mechanisms of dislocation formation and movements in different crystal lattices and their role in material strain hardening are considered. Grain boundaries and twin ones are described as dislocation rows imposed on each other

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

    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.

  8. The surgical treatment of the recurrent dislocation on the shoulder joint with minimum invasion anterior approach

    Ninković Srđan; Stanković Milan; Savić Dragan; Matijević Radmila; Milankov Miroslav

    2008-01-01

    Shoulder joint is one of the spherical joints and one of the most movable but also the most unstable joint of locomotive apparatus. The aims of this work are to review and analyze the results of medical treatment of frontal recurrent dislocations on the shoulder with open surgery technique on the Clinic for Orthopaedic Surgery and Traumatology in Novi Sad in the period from 2002 to 2005. Twenty one patients with anterior recurrent dislocations of the shoulder were operated on, 19 men and 2 wo...

  9. Ipsilateral dislocation of the shoulder and elbow joints with contralateral comminuted humeral fracture

    Ipsilateral dislocation of the shoulder and elbow joints is a rare and complex injury. During the last 25 years, only 3 cases have been reported in the literature. We report a 50-year-old woman who suffered ipsilateral elbow and shoulder dislocation with contralateral comminuted humeral fracture. Both shoulder and elbow joints were reduced, but the elbow was dislocated subsequently at follow-up. The reduction in the elbow was stabilized by a Kirschner wire that was removed at 3 weeks, and the elbow was then stable. A U-shaped coaptation splint was applied for the contralateral comminuted humeral fracture. At 6 months, she had acquired a nearly full range of motion of both shoulder and elbow with complete healing in the contralateral humerus. Although rare and complex, ipsilateral shoulder and elbow dislocation, which is the result of a high-energy trauma, can be treated conservatively. (author)

  10. Non-traumatic posterior atlanto-occipital joint dislocation

    Takechi, Yasuhiko; Iizuka, Haku; Sorimachi, Yasunori; Ara, Tsuyoshi; Nishinome, Masahiro; Takagishi, Kenji

    2010-01-01

    This report presents a case of non-traumatic posterior atlanto-occipital dislocation. A 36-year-old female was referred with a history of numbness of the extremities, vertigo and neck pain for 1 year. The patient had no history of trauma. The axial rotation of range of motion of the cervical spine was severely restricted. A lateral cervical radiograph in the neutral position demonstrated a posterior atlanto-occipital dislocation. A coronal view on a computed tomography (CT) reconstruction ima...

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

    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.

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

    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

  13. Arteriovenous Fistula Secondary to Recurrent Metacarpophalangeal Joint Dislocation: A Case Report

    Ha, Jennifer F.; Sieunarine, Kishore

    2009-01-01

    Acquired traumatic arteriovenous fistula in the hand is rare, and only a few cases have been reported in the literature. It should be considered as a possible complication when there is a persistent palpable lesion after the traumatic swelling in the hand has resolved. We report a case of a rare arteriovenous fistula secondary to recurrent metacarpophalangeal joint dislocation.

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

    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)

  15. Volar dislocation of the radiocarpal joint with volar radiocarpal ligament rupture: a case report

    Gokhan Meric

    2012-12-01

    Full Text Available Radiocarpal joint dislocation, with or without fracture of the radius, is an uncommon injury. Volar radiocarpal dislocation is often associated with injury to the dorsal capsular and ligamentous structures. It does not have clear information about the injury and functional outcomes of treatment. It has been reported successful results treatment of the radiocarpal dislocation with closed reduction cast immobilisation, Kirshner wire fixation and open reduction. We report a case of 19 years old man admitted to our emergency department who had radiocarpal dislocation, distal volar chip fracture and volar radiocarpal ligament rupture due to a motorbike accident. We treated open reduction of radiocarpal joint, internal fixation of fracture with Kirshner wire and velar radiocarpal ligament repair with anchor suture. 6 months after operation we observed the union of the fracture and that the joint was stable during controls and radiological examinations. We did not find any pain or discomfort during daily activity and found that the full range of motion. [Hand Microsurg 2012; 1(3.000: 107-110

  16. A comparison of ketamine versus etomidate for procedural sedation for the reduction of large joint dislocations

    Salen, Philip; Grossman, Michelle; Grossman, Michael; Milazzo, Anthony; Stoltzfus, Jill

    2016-01-01

    Study Objectives: Ketamine and etomidate are used for procedural sedation (PS) to facilitate the performance of painful procedures. We hypothesized that ketamine produces adequate and comparable sedation conditions for dislocated large joint reduction when compared to etomidate and results in fewer adverse events. Methods: This Institutional Review Board approved prospective trial compared a convenience sample of subjects, who were randomized to receive either ketamine or etomidate for PS to facilitate reduction of large joint dislocations. Following informed consent, subjects were assigned via a computer-generated algorithm to receive either etomidate (0.1 mg/kg) or ketamine (0.5 mg/kg) intravenously; if PS was not sufficient, subjects received repeat doses of etomidate or ketamine until adequate PS was achieved. The protocol's primary endpoint was a successful reduction of dislocated, large joints. Secondary endpoints included alteration in blood pressure, vomiting, recovery agitation, hypersalivation, laryngospasm, myoclonus, hypoxia, airway assistance with chin lift or jaw thrust, bag-valve-mask ventilation, endotracheal intubation, utilization of additional doses of ketamine or etomidate, and recovery time from sedation. Results: Total enrollment was eighty subjects, 46 in the ketamine cohort and 34 in the etomidate cohort. The two PS groups were comparable in terms of gender, age, and weight. There was no significant difference in the primary endpoint of large joint dislocation reduction between the ketamine and etomidate cohorts (46/46, 100%; 32/34, 94.1%; P – 0.1). Shoulder, hip, and ankle joints account for the majority of joint reductions in this trial. Titration of PS was necessary for almost half of each cohort as evidenced by the utilization of additional dosages of the sedative agents: ketamine (22/46, 47.8%) and etomidate (14/34, 41.2%; P – 0.56). Among secondary outcome variables, significant differences between ketamine and etomidate cohorts

  17. Reduction of temporomandibular joint dislocation: an ancient technique that has stood the test of time.

    Forshaw, R J

    2015-07-01

    The first known recorded evidence for the reduction of a mandibular joint dislocation is documented in a papyrus dated to c. 1500 BC that originated from ancient Egypt. This same technique was later discussed by Hippocrates in Greece and the Hippocratic corpus is referred to in early Islamic writings. It is detailed in medieval European texts and eventually was incorporated into modern dental and medical practice. Today, mandibular joint dislocation is probably not that common but to be included in an important ancient Egyptian treatise, predominately concerned with trauma to the head and neck, could suggest it was a more frequent occurrence in antiquity. This could relate to the heavy tooth wear, frequent antemortem tooth loss and the related sequelae of severe malocclusion and overclosure evident in many surviving ancient Egyptian skulls. PMID:26114704

  18. Lateral dislocation of the knee joint after total knee arthroplasty: a case report

    Ugutmen, Ender; Ozkan, Korhan; Unay, Koray; Mahirogullari, Mahir; Eceviz, Engin; Taser, Omer

    2008-01-01

    Background Total knee arthroplasty (TKA) is a successful therapy for functional improvement and pain relief in advanced symptomatic degeneration of the knee joint. But it can be associated with many complications, one of which is instability. Case presentation A 70-year-old woman was referred to our hospital because of right knee dislocation after TKA was performed on her right knee due to severe varus deformity and flexion contracture. This instability was caused by persistent MCL tightness ...

  19. Complete medial column dislocation at the cuneonavicular joint: an unusual Lisfranc-like injury.

    Schepers, T; de Jong, V M; Luitse, J S K

    2014-09-01

    Lisfranc injuries represent a wide spectrum of different injuries at the tarsometatarsal joint. Not all types fit the currently available classifications. This case illustrates a rare subtype of a Lisfranc injury, with a dislocation of the entire first ray. It is presented to create more awareness for midfoot injuries. This article reviews the literature and provides recommendations for the treatment of similar cases in the future. PMID:25063016

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

    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.

  1. Invited Hand Article: Current Concepts in Treatment of Fracture-Dislocations of the Proximal Interphalangeal Joint

    Haase, Steven C.; Chung, Kevin C.

    2014-01-01

    Background Proximal interphalangeal joint fracture-dislocations are common injuries that require expedient and attentive treatment for the best outcomes. Management can range from protective splinting and early mobilization to complex operations. In this review, the current concepts surrounding the managment of these injuries are reviewed. Methods A literature review was performed of all recent articles pertaining to proximal interphalangeal joint fracture-dislocation, with specific focus on middle phalangeal base fractures. Where appropriate, older articles, or articles on closely related injury types were included for completeness. The methodology and outcomes of each study were analyzed. Results When small avulsion fractures are present, good results are routinely obtained with reduction and early mobilization of stable injuries. Strategies for management of the unstable dorsal fracture-dislocation have evolved over time. To provide early stability, a variety of techniques have evolved, including closed, percutaneous, external, and internal fixation methods. Although each of these techniques can be successful in skilled hands, none have been subjected to rigorous, prospective, comparative trials. Volar dislocations fare less well, with significant loss of motion in many studies. Pilon fractures represent the most complicated injuries, and return of normal motion is not expected. Conclusion The best outcomes can be achieved by (1) establishing enough stability to allow early motion, (2) restoring gliding joint motion rather than non-congruent motion, and (3) restoring the articular surface congruity when possible. Although the majority of literature on this topic consists of expert opinion and retrospective case series, the consensus appears to favor less invasive techniques whenever possible. PMID:25415092

  2. Diagnostic challenges in acromioclavicular septic arthritis.

    Williams, Mark

    2016-01-01

    A 69-year-old man with Klinefelter's syndrome presented with a painful shoulder and staphylococcal sepsis. He received intravenous antibiotics while investigations were performed to locate the source of infection. MRI demonstrated infection in the acromioclavicular joint (ACJ). The patient clinically improved and a further 5 weeks of oral antibiotics were given. He remained asymptomatic at 2-year follow-up. Although ACJ septic arthritis is rare, independent of immune-competent status, a high index of suspicion is essential for prompt diagnosis. The condition presents additional diagnostic challenges due to unfamiliarity, the challenges of interpreting imaging, desire for radiological guided arthrocentesis and low volume aspirates. Overcoming these pitfalls is essential to avoid significant morbidity and mortality. PMID:27257000

  3. The surgical treatment of the recurrent dislocation on the shoulder joint with minimum invasion anterior approach

    Ninković Srđan

    2008-01-01

    Full Text Available Shoulder joint is one of the spherical joints and one of the most movable but also the most unstable joint of locomotive apparatus. The aims of this work are to review and analyze the results of medical treatment of frontal recurrent dislocations on the shoulder with open surgery technique on the Clinic for Orthopaedic Surgery and Traumatology in Novi Sad in the period from 2002 to 2005. Twenty one patients with anterior recurrent dislocations of the shoulder were operated on, 19 men and 2 women. The average age of those patients was 24.8 (15-40 year-olds. Ten patients had an injury of the left and 11 patients the injury of the right shoulder. There were eight handball players, four fighting skills players; two of them played volleyball and one was a basketball player. Six of them were not sportsmen. The preoperational and post operational mean value of the modified Rowe scale showed a statistically significant difference (P<0.001. Observing the patients after the operation in the period of 2 years, according to Neer scale, 3 patients (14.28% had great results (grade over 90, 16 patients (76.19% had a good result, (75-89, and only two patients (9.52% had results less than 75. The measuring of the volume of movements after physical treatment in 12 patients (57.14% has shown the decrease of the outside rotation. Open surgery treatment of the front unstable shoulder joint is reliable and time tested and it gives good clinical results in young sportsmen with undirected unstable, bigger number of dislocations and associated osseous defects. .

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

    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.

  5. Simultaneous Volar Dislocation of Distal Interphalangeal Joint and Volar Fracture-Subluxation of Proximal Interphalangeal Joint of Little Finger: A New Mechanism of Injury.

    Mozaffarian, Kamran; Bayatpour, Abdollah; Vosoughi, Amir Reza

    2016-10-01

    Simultaneous volar dislocation of distal interphalangeal (DIP) joint and volar fracture-subluxation of proximal interphalangeal (PIP) joint of the same finger has not been reported yet. A 19-year-old man was referred due to pain on the deformed left little finger after a ball injury. Radiographs showed volar dislocation of the DIP joint and dorsal lip fracture of the middle phalanx with volar subluxation of PIP joint of the little finger. This case was unique in terms of the mechanism of injury which was hyperflexion type in two adjacent joints of the same finger. The patient was treated by closed reduction of DIP joint dislocation and open reduction and internal fixation of the PIP joint fracture-subluxation and application of dorsal external fixator due to instability. Finally, full flexion of the PIP joint and full extension of the DIP joint were obtained but with 10 degree extension lag at the PIP joint and DIP joint flexion ranging from 0 degree to 30 degrees. Some loss of motion in small joints of the fingers after hyperflexion injuries should be expected. PMID:27595966

  6. Posterolateral dislocation of the knee joints:analysis of 9 cases

    顾敏琪; 邓磊; 刘沂

    2004-01-01

    Objective: To analyze the traumatic pathological characteristics of posterolateral dislocation of knee joints and its treatment.Methods: Nine cases of posterolateral dislocation of knee joint, 5 cases of fresh injuries (the fresh injury group) and 4 cases of old injuries ( the old injury group) were reviewed and analyzed. In the fresh injury group 4 cases failed in close reduction due to "buttonholing" through the medial joint, among them 3 cases underwent repair of the damaged ligaments. In the old injury group 2 cases underwent ACL and MCL repair only in acute stage, but re-dislocated. Of the rest 2 cases 1 was associated with peroneal nerve injury and the other was not treated in acute stage. One case was associated with comminuted fracture of the tibial condyle and popliteal artery injury. Open reduction was performed in 3 cases. One case was fixed with 2-crossed pin and another was fixed with one pin through the tibial and femoral condyle and second pin with olecranization fixation. Plaster immobilization for 6-8 weeks respectively was required. In the old injury group in 1 case ACL and PCL repair ( Augustine method ) and posterolateral structure were performed and olecranization fixation and plaster immobilization for 6 weeks was needed.Arthrodesis of the knee was done for the patient with comminuted fracture of the tibial condyle and popliteal artery injury.Results: All the cases were followed up for 1-23 years ( average 6 years). Knee stability in 4 cases with repair of the ligaments was improved, although PDT showed ( + ) with different degrees. The results of the patients treated with ligamentous reconstruction were much better than those of the patients without any repair. Conclusions: Well understanding of the traumatic pathological characteristics, repair of the damaged ligaments, augmentation of olecranization fixation and postoperative immobilization for 6 weeks are the key points of successful treatment.

  7. Irreducible open dorsal dislocation of the proximal interphalangeal joint: a case report.

    Muraoka, Shizuka; Furue, Yukihiro; Kawashima, Mahito

    2010-01-01

    We report a rare case of open dorsal dislocation of the proximal interphalangeal joint which needed operative reduction. A 39-year-old man injured his right middle finger while playing baseball. There was a laceration on the proximal interphalangeal crease, and the condyles of the proximal phalanx protruded through the wound. The flexor tendons had slipped behind the radial condyle, and made reduction impossible. After the flexor tendons and volar plate were replaced back into their normal position, the reduction was successful. Finally, the patient had full and painless motion of the digit. We review the reported cases of this injury in the relevant literature. PMID:20422730

  8. Histomorphologic Characteristics of Newly Formed Cavity of a Hip Joint in Dislocation in Experiment

    Ezhov I.Y.

    2013-06-01

    Full Text Available The aim of the investigation was to study in experiment the head of femur dislocation, which is a variety of transchondral damages, and the process of chondro- and osteogenesis in articular surface formation to create optimal conditions for their reparation and new formation. Materials and Methods. The experiment was carried out on 20 reproductive chinchilla rabbits. The head of femur was dislocated in experiment after joint capsule transaction, and exposed to dosing impact and force effect in the area of its upper pole. A blow was stricken by the device looking like an impact machine. The blow energy was regulated by changing load weight and the pendulum height. The animals were removed from the experiment 3, 7, 14, 30 days and 3 months after the injury. Results. For the initial few days in the dislocation area there were found fibrin effusions, hemorrhage, periosteal edema, and granulation tissue. In 2 weeks in fibrous tissue there were determined focal clusters of chondroblasts. By the end of the first month, near the head of femur, connective tissue was underlaid by newly formed fibrous cartilage with the areas of young hyaline cartilage forming a free margin. In 3 months a submarginal zone was formed of hyaline cartilage with ordered cytoarchitectonics of chondrocytes. Different-sized margins of the newly formed hyaline cartilage with the foci of complete osteogenesis in the wall of forming cavity (in the form of osseous tissue of sponge structure with the blood-forming bone marrow in interjoist were observed in close connection with periosteum of acetabular roof. Conclusion. A joint cavity forms on the basis of the mechanisms of pluripotent development of cambial cell elements towards chondro- and osteogenesis. Its successful formation can be accompanied by the mass of well blood-supplied muscles surrounding the dislocated head, periosteum of acetabular roof, as well as the capability of active movements the head of femur dislocated into

  9. Relação anatômica do nervo supraescapular com o processo coracoide, articulação acromioclavicular e acrômio Anatomical relationship of the suprascapular nerve to the coracoid process, acromio clavicular joint and acromion

    Bernardo Barcellos Terra

    2010-06-01

    Full Text Available OBJETIVO: Estabelecer a relação anatômica do nervo supraescapular (NSE localizado na fossa supraescapular com a borda medial da base do coracoide, face articular acromial da articulação acromioclavicular e a borda anterolateral do acrômio. MÉTODOS: Foram dissecados 16 ombros de 16 cadáveres, sendo nove masculinos e sete femininos, mensurando com auxílio do paquímetro a distância do nervo supraescapular (na sua passagem sob o ligamento transverso com pontos fixos determinados na borda medial da base do processo coracoide, na face articular do acrômio da articulação acromioclavicular e na borda anterolateral do acrômio, correlacionando com a idade e o sexo. Foram excluídos cadáveres com intervenção cirúrgica prévia. RESULTADOS: Com relação à medida do nervo supraescapular, na sua fossa à borda medial da base do processo coracoide, obtivemos uma média de 3,9cm (variando de 3,1cm a 5,2cm; com relação à articulação acromioclavicular, a média foi de 4,7 (3,9cm a 5,2cm; e, com relação à borda anterolateral do acrômio, a média foi de 6,1cm (5,7cm a 6,8cm. CONCLUSÃO: É fundamental o conhecimento exato da anatomia dos nervos da região anterior do ombro para evitar lesões iatrogênicas e para conseguir resultados satisfatórios no tratamento cirúrgico das doenças do ombro, seja ele realizado de forma aberta ou artroscópica.OBJECTIVE: To establish the anatomic relationship of the suprascapular nerve (SSN located in the suprascapular notch to the medial border of the base of the coracoid process, the medial acromial surface of the acromioclavicular joint and the anterolateral edge of the acromion. METHODS: We dissected 16 shoulders of 16 cadavers, 9 males and 7 females. The distance from the suprascapular nerve (in its course beneath the transverse ligament to certain fixed points in the medial base of the coracoid process was measured with the aid of a caliper, as well as to the articular surface of the acromion

  10. Delayed surgical treatment for a traumatic bilateral cervical facet joint dislocation using a posterior-anterior approach: a case report

    Shimada Takashi

    2013-01-01

    Full Text Available Abstract Introduction There have been few reports of patients with bilateral cervical facet dislocations that remain untreated for eight weeks or more. We report the case of a 76-year-old man with an old bilateral cervical facet joint dislocation fracture that was treated by posterior-anterior reduction and fixation. Case presentation A 76-year-old Asian man was involved in a road traffic accident. He presented with neck pain and arm pain on his right side, but motor weakness and paralysis were not observed. He was treated conservatively; however, instability and spondylolisthesis at the C5 to C6 joint increased eight weeks after the injury. We performed a posterior-anterior reduction and fixation. After surgery, bony union was achieved, and his neck pain and arm pain disappeared. Conclusion We recommend reduction and fixation surgery if a patient has an old bilateral facet joint dislocation fracture in the cervical spine.

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

    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.

  12. Neglected irreducible dislocation of the interphalangeal joint of the great toe: a case report.

    Hatori, Masahito; Goto, Masako; Tanaka, Kentaro; Smith, Richard A; Kokubun, Shoichi

    2006-01-01

    Irreducible dorsal dislocation of the interphalangeal joint of the great toe is rare. We report a case of a 58-year-old man with an irreducible interphalangeal joint of the great toe that had been untreated for 4 years. The mechanism of this injury was thought to be a combination of axial loading with a hyperextension force when the patient hit his great toe against a pipe. Invagination of the sesamoid became a barrier for manual reduction attempted after the initial injury. The patient did not seek treatment because of the minor deformity of the affected great toe and lack of severe symptoms. One year later, symptoms eventually developed on the plantar aspect of the great toe, particularly when the patient was walking upstairs. He decided to seek treatment as pain worsened and he became more active when he changed occupations 4 years later. Manual reduction was impossible. The patient was treated with operative exploration of the joint and arthrodesis of the great toe. The operative course was uneventful. At 4 years after surgery, the patient could walk, run, and walk up and down stairs without discomfort. PMID:16818156

  13. Comparison of different approaches to the reduction of anterior temporomandibular joint dislocation: a randomized clinical trial.

    Ardehali, M M; Tari, N; Bastaninejad, Sh; Amirizad, E

    2016-08-01

    This randomized clinical trial was designed to compare three different reduction methods for anterior temporomandibular joint (TMJ) dislocation. The three methods evaluated were the conventional method, wrist pivot method, and extraoral method. The study sample comprised 90 consecutive patients suffering from anterior dislocation of the TMJ, who were allocated randomly to one of the three groups. This study found success rates of 86.7% for the conventional method, 96.7% for the wrist pivot method, and 66.7% for the extraoral method. The extraoral method was more difficult for the physician and the patient than the other two methods. For the patients, the wrist pivot method was easier than the other methods. For the doctors, the extraoral method was significantly more difficult than the other methods. In conclusion, due to the absence of a biting risk with the extraoral method and the lack of a significant difference in success between this method and the conventional method, the extraoral method could be considered the appropriate first-line treatment where there is a risk of the patient biting the surgeon's hand. Given the overall benefits of the wrist pivot method, this method could be considered the first-line and gold standard treatment modality in other cases. PMID:27160610

  14. Traumatic dislocation of the incudostapedial joint repaired with fibrin tissue adhesive.

    Nikolaidis, Vasilios

    2011-03-01

    We present a case of traumatic dislocation of the incudostapedial joint (ISJ) and a simple method for controlled application of the glue using commercial fibrin tissue adhesive. A 26-year-old female presented to our ENT clinic for hearing impairment to her left ear 2 months after a head trauma due to a motorcycle accident. The audiogram revealed a 40- to 50-dB HL conductive hearing loss with a notch configuration in bone conduction curve on the left ear. Computed tomography of the left temporal bone revealed a longitudinal fracture line. An exploratory tympanotomy was performed under general anesthesia. The ISJ was found dislocated while the incus was trapped by the edges of the bony lateral attic wall fracture. A small bony edge that impeded incus movement was removed and a small amount of the glue was precisely applied to the lenticular process of the incus with an angled incision knife. The long process of the incus was firmly pressed over the stapes for 30 seconds with a 90° hook and 60 seconds after the application of the glue the ISJ was repaired. One year after our patient achieved full airbone gap (ABG) closure (ABG, ≤10 dB HL), while she demonstrated overclosure in frequencies 2 and 4 kHz. Fibrin tissue glue allowed safe, rapid, and accurate repair of the ISJ and resulted in an anatomically normal articulation as the mass and shape of the ossicles was preserved. Moreover, our patient achieved full ABG closure. PMID:21344438

  15. Lateral dislocation of the knee joint after total knee arthroplasty: a case report

    Ugutmen, Ender; Ozkan, Korhan; Unay, Koray; Mahirogullari, Mahir; Eceviz, Engin; Taser, Omer

    2008-01-01

    Background Total knee arthroplasty (TKA) is a successful therapy for functional improvement and pain relief in advanced symptomatic degeneration of the knee joint. But it can be associated with many complications, one of which is instability. Case presentation A 70-year-old woman was referred to our hospital because of right knee dislocation after TKA was performed on her right knee due to severe varus deformity and flexion contracture. This instability was caused by persistent MCL tightness and iatrogenic lateral collateral, arcuate ligament, and popliteus tendon injury. The torn lateral collateral ligament and arcuate ligament were sutured with no. 2 non-absorbable (Ethibond) sutures with plication of the posterolateral knee capsule. A deep-dish liner was inserted to optimize soft tissue tension. Conclusion This is a very severe complication, and surgeons must be cautious about ligament balancing and soft tissue resection during TKA for severe varus and valgus deformities. PMID:18687153

  16. Complex Dorsal Dislocation of the Metacarpophalangeal Joint: The Deep Transverse Metacarpal Ligament as a Barrier to Reduction

    DeCoster, Thomas A; McGrew, Deborah; Omer, George E.

    1988-01-01

    Dorsal dislocation of the second metacarpophalangeal (MCP) joint may involve dorsal displacement of the deep transverse metacarpal ligament (DTMCL). In addition to retraction of the volar plate, reduction of the deep transverse metacarpal ligament to its normal volar position is necessary to achieve stable, complete reduction of the MCP joint. The factors associated with this pathologic condition are reviewed as well as an anatomic study of the mechanism of injury.

  17. Bilateral anterior shoulder dislocation

    Meena, Sanjay; Saini, Pramod; Singh, Vivek; Kumar, Ramakant; Trikha, Vivek

    2013-01-01

    Shoulder dislocations are the most common major joint dislocations encountered in the emergency departments. Bilateral shoulder dislocations are rare and of these, bilateral posterior shoulder dislocations are more prevalent than bilateral anterior shoulder dislocations. Bilateral anterior shoulder dislocation is very rare. We present a case of 24-year-old male who sustained bilateral anterior shoulder dislocation following minor trauma, with associated greater tuberosity fracture on one side...

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

    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)

  19. Percutaneous Screw Fixation of Crescent Fracture-Dislocation of the Sacroiliac Joint.

    Shui, Xiaolong; Ying, Xiaozhou; Mao, Chuanwan; Feng, Yongzeng; Chen, Linwei; Kong, Jianzhong; Guo, Xiaoshan; Wang, Gang

    2015-11-01

    Crescent fracture-dislocation of the sacroiliac joint (CFDSIJ) is a type of lateral compression pelvic injury associated with instability. Open reduction and internal fixation is a traditional treatment of CFDSIJ. However, a minimally invasive method has never been reported. The purpose of this study was to assess the outcome of closed reduction and percutaneous fixation for different types of CFDSIJ and present their clinical outcome. The authors reviewed 117 patients diagnosed with CFDSIJ between July 2003 and July 2013. Closed reduction and percutaneous fixation was performed in 73 patients. Treatment selection was based on Day's fracture classification. For type I fractures, fixation perpendicular to the fracture line were performed. For type II fractures, crossed fixation was performed. For type III fractures, fixation was performed with iliosacral screws. Forty-four patients were treated by open reduction and plate fixation. Demographics, fracture pattern distribution, blood loss, incision lengths, revision surgeries, radiological results, and functional scores were compared. All 117 patients were followed for more than 6 months (mean, 14 months [range, 6-24 months]). Blood loss, extensive exposure, duration of posterior ring surgery, duration of hospital stay, and infection rates were lower in the closed group (P<.01). Patients in the closed group achieved better functional performance (P<.01). There were no significant differences in reduction quality (P=.32), revision surgery rates (P=.27), and iatrogenic neurologic injuries (P=.2) between the 2 groups. The authors' results indicate that closed reduction and percutaneous fixation is a safe and effective surgical method for CFDSIJ. PMID:26558677

  20. Comparative study on double Endobutton plate and clavicular hook plate for repair of Tossy grade Ⅲ acromioclavicular dislocation%双带袢纽扣钢板与锁骨钩钢板治疗TossyⅢ型肩锁关节脱位的疗效评价

    胡晓波; 蒋电明; 阳明明; 何镇江

    2014-01-01

    目的 探讨双带袢纽扣(Endobutton)钢板与锁骨钩钢板(clavicular hook plate,CHP)治疗TossyⅢ型肩锁关节脱位的效果. 方法 回顾性分析2010年1月-2012年8月收治的TossyⅢ型肩锁关节脱位患者82例,按治疗方式分为双Endobutton组(36例)和CHP组(46例),比较两组手术情况及住院指标,治疗后患肩视觉模拟评分(visual analogue scale,VAS)、外展上举及前屈上举活动度、肩关节Constant-Murley评分以及并发症情况. 结果 两组手术时间、出血量、住院时间差异均无统计学意义.双Endobutton组恢复工作时间(13.1±1.4)周,明显短于CHP组(15.5±2.6)周(P<0.01).术后并发症方面,两组差异无统计学意义.术后12个月双Endobutton组VAS (2.1±0.7)分,显著低于CHP组(2.9±0.8)分(P<0.05);患肩外展上举和前屈上举活动度[(138.6±15.7)°、(140.3±17.6)°]显著大于CHP组[(91.7±8.4)°、(96.7±l0.5)°](P<0.05). 结论 治疗TossyⅢ型肩锁关节脱位,双Endobutton钢板较CHP能更明显改善患者早期肩关节疼痛,恢复快,肩关节功能恢复更佳,且可避免二次手术取出.%Objective To compare the outcome of double Endobutton plate versus clavicular hook plate (CHP) in treatment of Tossy grade Ⅲ acromioclavicular dislocation.Methods A cohort of 82 patients with Tossy grade Ⅲ acromiocavicular dislocation treated between January 2010 and August 2012 were reviewed retrospectively.Based on the treatment choices,the patients were divided into double Endobutton group (36 cases) and CHP group (46 cases).Operative situation,in-hospital parameters,and postoperative visual analogue scale (VAS) of the shoulder,shoulder abduction-rise or anteflexionrise,Constant-Murley shoulder score as well as complications were evaluated.Results There were no statistical differences between the two groups in aspects of operation time,intraoperative blood loss,and length of stay.Mean time to return to work was (13.1 ± 1.4) weeks in double Endobutton

  1. Epidemiological survey of orthopedic joint dislocations based on nationwide insurance data in Taiwan, 2000-2005

    Yang Nan-Ping

    2011-11-01

    Full Text Available Abstract Background The epidemiology of acute orthopedic dislocations is poorly understood. A nationwide database provides a valuable resource for examining this issue in the Taiwanese population. Methods A 6-year retrospective cohort study of 1,000,000 randomly-sampled beneficiaries from the year 2005 was used as the original population. Based on the hospitalized and ambulatory data, the concomitant ICD9-CM diagnosis codes and treatment codes were evaluated and classified into 8 and 3 major categories, respectively. The cases matching both inclusive criteria of dislocation-related diagnosis codes and treatment codes were defined as incident cases. Results During 2000-2005, the estimated annual incidence (per 100,000 population of total orthopedic dislocations in Taiwan was 42.1 (95%CI: 38.1-46.1. The major cause of these orthopedic dislocations was traffic accidents (57.4%, followed by accident falls (27.5%. The annual incidence dislocation by location was shoulder, 15.3; elbow, 7.7; wrist, 3.5; finger, 4.6; hip, 5.2; knee, 1.4; ankle, 2.0; and foot, 2.4. Approximately 16% of shoulder dislocations occurred with other concomitant fractures, compared with 17%, 53%, 16%, 76% and 52%, respectively, of dislocated elbow, wrist, hip, knee, and ankle cases. Including both simple and complex dislocated cases, the mean medical cost was US$612 for treatment of a shoulder dislocation, $504 for the elbow, $1,232 for the wrist, $1,103 for the hip, $1,888 for the knee, and $1,248 for the ankle. Conclusions In Taiwan, three-quarters of all orthopedic dislocations were of the upper limbs. The most common complex fracture-dislocation was of the knee, followed by the wrist and the ankle. Those usually needed a treatment combined with open reduction of fractures and resulted in a higher direct medical expenditure.

  2. AO锁骨钩钢板中长期留置对肩锁关节脱位术后肩关节功能的影响%Effects of long-and mid-term indwelling of AO clavicular hook plate on the shoulder function following acromioclavicular dislocation surgery

    翟艳斌; 张永红; 王东

    2013-01-01

    目的 探讨AO锁骨钩钢板(CHP)中、长期留置对肩锁关节脱位(RockwoodⅢ~Ⅴ型)术后肩关节功能的影响. 方法 回顾性分析2002年 12月至2011年5月行切开复位AO CHP内固定治疗的95例肩锁关节脱位患者资料,男80例,女15例;年龄20 ~ 63岁,平均45.0岁;Rockwood分型:Ⅲ型40例,Ⅳ型35例,Ⅴ型20例;受伤至手术时间为2 ~7 d,平均4.6d.其中70例患者术后留置CHP,25例患者于术后12 ~ 23个月 (平均16.5个月)取出CHP.采用美国加州大学(UCLA)肩关节评分系统评定疗效,并比较CHP留置患者的患侧与健侧、CHP留置与取出患者患侧的肩关节功能. 结果 95例患者术后获7.5个月至9年(平均38个月)随访.70例CHP留置患者中,发生肩峰下骨侵蚀45例,内固定物断裂3例,肩峰撞击13例,螺钉松动2例,肩周炎5例,并发症发生率为97.1% (68/70).25例取出CHP患者中,发生肩峰下骨侵蚀3例,无肩锁关节再次脱位发生,并发症发生率为12.0%(3/25).70例CHP留置患者患侧的UCLA评分[(27.0±11.0)分]低于其健侧[(34.0±1.0)分]和CHP取出患者患侧评分[(32.0±6.5)分]. 结论 AO CHP中、长期留置对肩锁关节脱位(Rockwood Ⅲ~Ⅴ型)术后的肩关节功能存在不良影响,且术后并发症发生率非常高.%Objective To investigate the effects of long-and mid-term indwelling AO clavicular hook plate (CHP) on the shoulder function following surgery for acromioclavicular dislocation(from grade Ⅲ to grade Ⅴ by Rockwood's classification).Methods A retrospective study was done of 95 patients with acromioclavicular dislocation who had been fixed with AO CHP from December 2002 to May 2011.They were 80 men and 15 women,aged from 20 to 63 years (average,45.0 years).By the Rockwood's classification,there were 40 cases of type Ⅲ,35 ones of type Ⅳ and 20 ones of type Ⅴ.Time from injury to surgery ranged from 2 to 7 days (average,4.6 days).The CHP was indwelling in 70 patients but removed in 25

  3. Irreducible palmar metacarpophalangeal joint dislocation due to junctura tendinum interposition: a case report and review of the literature.

    Patel, M R; Bassini, L

    2000-01-01

    Three different anatomic structures have been reported to prevent reduction of a palmar dislocation of metacarpophalangeal joint: dorsal capsule, palmar plate, and a ruptured collateral ligament. In our case, extensor digitorum communis of the fifth finger and extensor digiti minimi subluxated on the ulnar side of the fifth metacarpal neck. Extensor digitorum communis of the fourth finger remained in its anatomic location. The junctura tendinum connecting the fourth and fifth extensor digitorum communis tendons slipped distal and then palmar to the metacarpal head, where it was trapped between the metacarpal neck and the base of the proximal phalanx. It was easily pulled out and the joint promptly reduced. Residual subluxation persisted due to rupture of the radial collateral ligament and the dorsal capsule. Repair restored joint reduction and stability. (J Hand Surg 2000; 25A:166-172. PMID:10642488

  4. Ipsilateral fracture dislocations of the hip and knee joints with contralateral open fracture of the leg: a rare case and its management principles

    Sen Ramesh Kumar

    2011-06-01

    Full Text Available 【Abstract】This paper discussed the injury mecha- nism and management of a patient who had concomitant ipsilateral hip and knee dislocations and contralateral open leg fracture. A 32-year-old man presented with ipsilateral fracture- dislocations of the left hip (Pipkin’s type IV and knee (Moore II joints and contralateral open fracture of the leg bones after a car accident. After emergency resuscitative measures, the hip joint was reduced and Pipkin’s fracture was fixed using Ganz approach with lag screws; knee joint was reduced closely and tibial plateau fracture was stabi- lized with lateral buttress plate and a transarticular span- ning fixator. The open fracture on the other leg was de- brided and fixed with an external fixator. There was no insta- bility in both joints after fixation when he was examined under anesthesia. The fractures united after 3 months and the patient had no residual instability of hip and knee. There was no clinical or radiological evidence of osteonecrosis in the hip joint after 6 months. At one-year follow-up, he had satisfactory functional outcome with almost normal range of motion at both joints. Ipsilateral hip and knee dislocations are rare injuries and more caution is needed for early diagnosis. A timely appro- priate intervention can provide good functional outcome to the patient in this situation. Key words: Hip dislocation; Knee dislocation; Fractures, bone

  5. Treatment of total dislocations of the ankle joint%踝关节完全脱位的治疗

    洪建军; 余可和; 赖红燕; 周一飞; 余洋; 左海强

    2010-01-01

    Objective To explore mechanism and treatment of total dislocations of the ankle joint.Methods Thirty-nine patients with total dislocations of the ankle joint were treated in our department from January 2003 to December 2008. There were 25 males and 14 females. Their ages ranged from 14 to 69 years old, averaging 31.6 years old. There were 10 cases of closed injury and 29 open injury; 23 cases of fracture-dislocation and 16 dislocation. According to the direction of talus dislocation, there were 15 cases of medial dislocation, 10 posterior dislocation, 10 lateral dislocation and 4 upward dislocation. Seven cases received conservative treatment and 32 surgery. Seven cases underwent flap transfer at the second stage and 2 amputation of the total ankle joint. Results Thirty-five patients were followed up for 1 to 4 years (average, 26 months). According to the AOFAS functional evaluation system, their pain score averaged 40,their functional score 50, and their objective sign score 10. The mean postoperative score was 86. 5(ranging from 48 to 96). Conclusions To prevent instability and traumatic arthritis of the ankle joint, it is essential to secure fine reduction and fixation of the fracture-dislocations, as well as repair of the ligaments of the ankle joint at an early stage. As skin necrosis often occurs in open dislocations, it is also important to prevent infection of the ankle joint by early flap transfer.%目的 探讨踝关节完全脱位的损伤机制与疗效.方法 2003年1月至2008年12月共收治39例踝关节完全脱位患者,男25例,女14例;年龄14~69岁,平均31.6岁.闭合性脱位10例,开放性脱位29例;伴踝关节骨折23例.按距骨移位方向分类:内侧脱位15例,外侧脱位10例,踝关节后脱位10例,旋转分离向上脱位4例.保守治疗7例,闭合复位短腿石膏固定6周;手术治疗32例,包括骨折脱位复位内固定22例,其中行外侧副韧带修复6例,三角韧带修复3例;单纯行三角韧带修复2

  6. Rehabilitation of a Completely Edentulous Patient with Nonreducible Bilateral Anterior Dislocation of the Temporomandibular Joint: A Prosthodontic Challenge-Clinical Report.

    Momani, Moath; Abdallah, Mohamed-Nur; Al-Sebaie, Derar; Tamimi, Faleh

    2016-07-01

    Nonreduced bilateral anterior dislocation of the temporomandibular joint (TMJ) is an extremely rare condition, and its prosthodontic rehabilitation is a clinical challenge, especially in patients who refuse to or cannot undergo surgery. There are no previous clinical reports of successful or standardized prosthetic rehabilitation approaches for patients with this condition. This clinical report describes the successful prosthodontic management of an edentulous patient with nonreduced bilateral anterior dislocation of the TMJ. PMID:26216338

  7. Acute spontaneous atraumatic bilateral anterior dislocation of the shoulder joint with Hill-Sachs lesions: first reported case and review of literature

    Manoharan, Gopikanthan; Singh, Rohit; Ahmed, Bessam; Kathuria, Vinod

    2014-01-01

    The anatomy of the shoulder joint comprises a relatively large humeral head with a shallow glenoid cavity allowing a remarkable range of motion at the expense of inherent instability. Despite anterior shoulder dislocations being the most common type encountered, bilateral dislocations are rare and almost always posterior. The aetiology is usually direct or indirect trauma related to sports, seizures, electric shock or electroconvulsive therapy. We present the first reported case of atraumatic...

  8. Successful closed manipulation of a pure lateral traumatic dislocation of the elbow joint using a modified Stimson's technique: a case report

    Khan Sameer K

    2008-05-01

    Full Text Available Abstract Introduction Pure lateral elbow dislocation is rare, and a successful closed reduction is even rarer. Reduction can be hindered by swelling, soft tissue interposition or associated fractures. Case presentation We present a pure lateral traumatic dislocation of the elbow joint in a 40-year-old man. This was successfully manipulated and reduced in casualty using a modification of the gravity-aided 'hanging arm' technique originally described for shoulder dislocations by Stimson. Conclusion We strongly recommend the use of this simple technique in these rare yet difficult injuries, in order to avoid potential complications with general anaesthesia and surgery.

  9. 肩关节后脱位3例报告%Posterior dislocation of shoulder joint in three cases

    寸新华; 李伟强; 鲁宁; 杨阳

    2011-01-01

    Objective By analyzing the diagnosis and treatment of the posterior shoulder dislocation, so as to improve its understanding and reduce the missed diagnosis and misdiagnosis. Methods Retrospective analysis was conducted in three patients with posterior shoulder dislocation, and clinical presentation, imaging characteristics and treatment were analyzed. Results The follow-up time ranged from 6 to 24 months. Shoulder joint movement was good in 2 cases, with 30 points and 33 points respectively scored by UCLA score system. And shoulder joint movement was limited in 1 case, with 25 points by UCLA score system. Conclusion Insufficient understanding is the main reason of the missed diagnosis, so careful physical examinations combined with appropriate imaging studies may prevent the missed diagnosis of posterior dislocation of the shoulder.%目的 通过分析肩关节后脱位的诊治情况,探讨其诊断及治疗方法,从而提高对这一损伤的认识,减少误漏诊.方法 回顾分析3例肩关节后脱位患者的临床资料,分析其临床表现,影像学特点及治疗方法.结果 随访6~24个月,2例肩关节活动良好,美国加州大学肩关节评分系统(UCLA)评分为30分、33分;1例肩关节活动受限,UCLA评分25分.结论 临床对该症认识不足是造成漏诊的主要原因,仔细的体检结合合适的影像学检查可以预防肩关节后脱位早期漏诊.

  10. Epidemiological survey of orthopedic joint dislocations based on nationwide insurance data in Taiwan, 2000-2005

    Yang Nan-Ping; Chen Hou-Chaung; Phan Dinh-Van; Yu I-Liang; Lee Yi-Hui; Chan Chien-Lung; Chou Pesus; Renn Jenn-Huei

    2011-01-01

    Abstract Background The epidemiology of acute orthopedic dislocations is poorly understood. A nationwide database provides a valuable resource for examining this issue in the Taiwanese population. Methods A 6-year retrospective cohort study of 1,000,000 randomly-sampled beneficiaries from the year 2005 was used as the original population. Based on the hospitalized and ambulatory data, the concomitant ICD9-CM diagnosis codes and treatment codes were evaluated and classified into 8 and 3 major ...

  11. Atlantoaxial dislocation

    Vijendra K Jain

    2012-01-01

    Full Text Available Atlanto-axial dislocations (AADs may be classified into four varieties depending upon the direction and plane of the dislocation i.e. anteroposterior, rotatory, central, and mixed dislocations. However, from the surgical point of view these are divided into two categories i.e. reducible (RAADs and irreducible (IAADs. Posterior fusion is the treatment of choice for RAAD. Transarticular screw fixation with sub-laminar wiring is the most stable& method of posterior fusion. Often, IAAD is due to inadequate extension in dynamic X-ray study which may also be due to spasm of muscles. If the anatomy at the occipito-atlanto-axial region {O-C1-C2; O: occiput, C1: atlas, C2: axis} is normal on X-ray, the dislocation should be reducible. In case congenital anomalies at O-C1-C2 and IAAD are seen on flexion/extension studies of the cervical spine, the C1-C2 joints should be seen in computerized tomography scan (CT. If the C1-C2 joint facet surfaces are normal, the AAD should be reducible by cervical traction or during surgery by mobilizing the joints. The entity termed "dolichoodontoid" does not exist. It is invariably C2-C3 (C3- third cervical vertebra fusion which gives an appearance of dolichoodontoid on plain X-ray or on mid-saggital section of magnetic resonance imaging (MRI or CT scan. The central dislocation and axial invagination should not be confused with basilar invagination. Transoral odontoidectomy alone is never sufficient in cases of congenital IAAD, adequate generous three-dimensional decompression while protecting the underlying neural structures should be achieved. Chronic post-traumatic IAAD are usually Type II odontoid fractures which get malunited or nonunited with pseudoarthrosis in dislocated position. All these dislocations can be reduced by transoral removal of the offending bone, callous and fibrous tissue.

  12. Systematics of glenohumoral and acromioclavicular arthritis; Systematik der glenohumeralen und akromioklavikulaeren Arthrose

    Seifarth, A. [Klinikum Augsburg, Klinik fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie, Augsburg (Germany); Roemer, F. [Klinikum Augsburg, Klinik fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie, Augsburg (Germany); Universitaetsklinikum Erlangen, Radiologisches Institut, Erlangen (Germany)

    2015-03-01

    A common risk factor for osteoarthritis (OA) of the glenohumeral joint is instability and is often observed as a sequel to dislocation. Altered biomechanics will ultimately result in joint degeneration including osteophyte development at the lower margin of the humerus, glenoidal cartilage loss and surface deformity. An OA of the glenohumeral joint is often coexistent with soft tissue derangement of the shoulder. In advanced stages defects of the rotator cuff and OA of the glenohumeral joint may accelerate disease progression. Degenerative changes of the acromioclavicular joint (AC joint) are commonly seen in older persons with only modest correlation with clinical symptoms. Symptomatic OA of the AC joint is often concomitantly observed with degenerative changes of the glenohumeral joint. Standard radiographs are the basis of a structural assessment of shoulder OA but lack correlation with clinical symptoms and are insensitive for the detection of early degenerative changes. Magnetic resonance imaging (MRI) provides increased sensitivity for the detection of cartilage defects and reveals relevant soft tissue changes, such as lesions of the glenoid labrum and capsuloligamentous structures, which are seen in conjunction with instability. It is also the method of choice to detect clinically relevant bone marrow edema-like lesions or synovial changes that are associated with symptomatic OA. Standard radiographs are not applicable for detection of early degenerative changes. Once OA is suspected clinically, MRI is the method of choice for further structural assessment. The administration of an intravenous contrast agent is useful for assessing synovitis, which commonly correlates with clinical disease manifestations. For preoperative and surgical planning of joint replacement, MRI or CT should be used. (orig.) [German] Eine haeufige Ursache der Omarthrose ist die Mikro- und Makroinstabilitaet, oft infolge von Luxationen. Bei veraenderter Biomechanik kommt es im Verlauf

  13. Traumatic Elbow Dislocations

    Iordens, Gijs

    2014-01-01

    markdownabstractThe elbow is the second most common major joint to dislocate after the shoulder in the adult population. Its stability is highly dependent on a complex interaction between bony articulations, capsuloligamentous structures and dynamic muscle restraints. Dislocations are traditionally classified by the presence (complex dislocations) or absence (simple dislocations) of associated fractures and by the direction of the displacement of the forearm relative to the humerus. The gener...

  14. A rare combined injury of dorsal fracture-dislocation of four carpometacarpal joints and trapezium, trapezoid and distal radius bone fractures.

    Touloupakis, Georgios; Stuflesser, Wilfried; Antonini, Guido; Ferrara, Fabrizio; Crippa, Cornelio; Lettera, Maria Gabriella

    2016-01-01

    Incorrect or delayed diagnosis and treatment of the carpometacarpal fracture-dislocations is often associated with poor prognosis. We present a rare case of unusual pattern of injury, involving dorsal dislocation of four ulnar carpometacarpal joints, associated with fracture of the trapezium, a burst fracture of the trapezoid  bone and an extra-articular fracture of the third distal  of the radius. The first surgical intervention was followed by unsatisfactory results, confirmed by the CT scans. A second surgery followed and an open reduction and pinning with K wires performed. Post-operative follow up lasting for nine months revealed a very good surgical outcome. PMID:27163903

  15. Dynamic posterior stabilization of shoulder hemiarthroplasty in long-standing neglected posterior dislocation of the glenohumeral joint

    Shyam Kumar A; Oakley Jeremy; Wootton Jamie

    2008-01-01

    Posterior dislocations of the shoulder are rare. They account for less than 3% of all shoulder dislocations. The treatment of neglected bilateral posterior dislocation of the shoulder is controversial. We present a novel operative technique to stabilize a shoulder hemiarthroplasty that we used in the treatment of a chronic posterior dislocation of a shoulder with an acute four-part fracture of the proximal humerus.

  16. Dynamic posterior stabilization of shoulder hemiarthroplasty in long-standing neglected posterior dislocation of the glenohumeral joint

    Shyam Kumar A

    2008-01-01

    Full Text Available Posterior dislocations of the shoulder are rare. They account for less than 3% of all shoulder dislocations. The treatment of neglected bilateral posterior dislocation of the shoulder is controversial. We present a novel operative technique to stabilize a shoulder hemiarthroplasty that we used in the treatment of a chronic posterior dislocation of a shoulder with an acute four-part fracture of the proximal humerus.

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

    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

  18. Ipsilateral fracture dislocations of the hip and knee joints with contralateral open fracture of the leg: a rare case and its management principles

    Ramesh Kumar Sen; Sujit Kumar Tripathy; Vibhu Krishnan; Tarun Goyal; Vanyambadi Jagadeesh

    2011-01-01

    This paper discussed the injury mechanism and management of a patient who had concomitant ipsilateral hip and knee dislocations and contralateral open leg fracture.A 32-year-old man presented with ipsilateral fracturedislocations of the left hip (Pipkin's type Ⅳ) and knee (Moore Ⅱ)joints and contralateral open fracture of the leg bones after a car accident. After emergency resuscitative measures, the hip joint was reduced and Pipkin's fracture was fixed using Ganz approach with lag screws; knee joint was reduced closely and tibial plateau fracture was stabilized with lateral buttress plate and a transarticular spanning fixator. The open fracture on the other leg was debrided and fixed with an external fixator. There was no instability in both joints after fixation when he was examined under anesthesia. The fractures united after 3 months and the patient had no residual instability of hip and knee. There was no clinical or radiological evidence of osteonecrosis in the hip joint after 6 months. At one-year follow-up, he had satisfactory functional outcome with almost normal range of motion at both joints.Ipsilateral hip and knee dislocations are rare injuries and more caution is needed for early diagnosis. A timely appropriate intervention can provide good functional outcome to the patient in this situation.

  19. Traumatic Elbow Dislocations

    G.I.T. Iordens (Gijs)

    2014-01-01

    markdownabstractThe elbow is the second most common major joint to dislocate after the shoulder in the adult population. Its stability is highly dependent on a complex interaction between bony articulations, capsuloligamentous structures and dynamic muscle restraints. Dislocations are traditionally

  20. Posterior talar fracture with dislocation of both talo-navicular and subtalar joints: a variant type II of the Sneppens classification

    Galanopoulos, Ilias; Fogg, Quentin; Ashwood, Neil

    2012-01-01

    A 63-year-old man fell from a ladder, thus causing an axial compression injury to the right ankle. Severe deformity was evident and the ankle could not be reduced by simple manipulation. The skin was tented and appearing critically contused. Radiographs revealed an oblique fracture of the posterior aspect of the talar body with dislocation of both the talo-navicular and subtalar joints, an injury previously not described in the literature. The fracture–dislocation was anatomically reduced within 3 h of presentation and stability achieved with two headless buried compression screws. CT scan confirmed anatomical reduction and the patient remained non-weight bearing in a cast for 6 weeks. One year postoperatively, the patient remains pain-free with no radiological signs of avascular necrosis of the talus. This injury is unique and despite its severity and soft tissue compromise good quality reduction and internal fixation resulted in an excellent clinical outcome. PMID:22847568

  1. Multiligamentous injuries and knee dislocations.

    Gimber, Lana H; Scalcione, Luke R; Rowan, Andrew; Hardy, Jolene C; Melville, David M; Taljanovic, Mihra S

    2015-11-01

    Complex capsular ligamentous structures contribute to stability of the knee joint. Simultaneous injury of two or more knee ligaments, aside from concurrent tears involving the anterior cruciate and medial collateral ligaments, is considered to be associated with femorotibial knee dislocations. Proximal tibiofibular joint dislocations are not always easily recognized and may be overlooked or missed. Patellofemoral dislocations can be transient with MR imaging sometimes required to reach the diagnosis. In this article, the authors describe the mechanism of injury, ligamentous disruptions, imaging, and treatment options of various types of knee dislocations including injuries of the femorotibial, proximal tibiofibular, and patellofemoral joints. PMID:26002747

  2. Complications following arthroscopic fixation of acromioclavicular separations: a systematic review of the literature

    Woodmass JM

    2015-04-01

    Full Text Available Jarret M Woodmass,1 John G Esposito,1 Yohei Ono,1,2 Atiba A Nelson,1 Richard S Boorman,1 Gail M Thornton,1,3 Ian KY Lo1 1Department of Surgery, Section of Orthopaedic Surgery, McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, Canada; 2Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, Nagoya, Japan; 3Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada Purpose: Over the past decade, a number of arthroscopic or arthroscopically assisted reconstruction techniques have emerged for the management of acromioclavicular (AC separations. These techniques provide the advantage of superior visualization of the base of the coracoid, less soft tissue dissection, and smaller incisions. While these techniques have been reported to provide excellent functional results with minimal complications, discrepancies exist within the literature. This systematic review aims to assess the rate of complications following these procedures. Methods: Two independent reviewers completed a search of Medline, Embase, PubMed, and the Cochrane Library entries up to December 2013. The terms “Acromioclavicular Joint (MeSH” OR “acromioclavicular* (text” OR “coracoclavicular* (text” AND “Arthroscopy (MeSH” OR “Arthroscop* (text” were used. Pooled estimates and 95% confidence intervals were calculated assuming a random-effects model. Statistical heterogeneity was quantified using the I2 statistic. Level of evidence: IV Results: A total of 972 abstracts met the search criteria. After removal of duplicates and assessment of inclusion/exclusion criteria, 12 articles were selected for data extraction. The rate of superficial infection was 3.8% and residual shoulder/AC pain or hardware irritation occurred at a rate of 26.7%. The rate of coracoid/clavicle fracture was 5.3% and occurred most commonly with techniques utilizing bony tunnels. Loss of AC joint reduction occurred in 26

  3. 环杓关节脱位一例并文献复习%Cricoarytenoid Joint Dislocation:Report of One Case and Literature Review

    邹小华; 杜云峰; 刘艳秋; 高鸿

    2014-01-01

    环杓关节脱位是全麻插管的一种少见并发症,一般可以通过临床症状及纤维喉镜等检查确诊。早期复位通常能取得良好的疗效,若延误诊断及治疗时机则可能导致永久的发声异常。本文报道了1例全麻插管后出现发声困难、饮水呛咳等症状,但纤维喉镜和CT检查不支持环杓关节脱位,最终通过诊断性复位确诊并通过2次全麻下环杓关节复位取得较好疗效的患者,并对相关文献进行回顾性分析,以加强临床医师对该疾病的认识、提高诊治能力。%Cricoarytenoid joint dislocation,arare complication,can be usually diagnosed through clinical symptoms and fibrolaryngoscope et al. Early reduction can usually get a good effect,and delayed diagnoses and treatments may lead to per-manent vocal abnormalities. This article reports a case of dysphonia,drinking cough and other symptoms after anesthesia intuba-tion. Fibrolaryngoscope and CT did not support cricoarytenoid joint dislocation,the diagnosis was made by a diagnostic reset and 2 times of cricoarytenoid joint reduction achieved good curative effect. Relevant literatures were analyzed retrospectively to en-hance the understanding of the disease and improve clinicians′capacity of diagnosis and treatment.

  4. 不修复喙锁韧带的锁骨钩钢板固定治疗TossyⅡ型和Ⅲ型肩锁关节脱位的疗效对比%Curative Effect of Clavicular Hook Plate Fixation Without Fixing Coracoclavicular Ligament in the Treatment of Tossy Type II and Type III Dislocation of the Shoulder

    何炜; 何发胜; 张海波; 蔡克冬

    2015-01-01

    目的:探讨锁骨钩板(CHP)固定但不修复喙锁韧带治疗急性 Tossy Ⅱ、Ⅲ型肩锁关节脱位的疗效对比。方法选取2011年1月~2014年3月采用锁骨钩钢板内固定治疗的44例新鲜 Tossy Ⅱ、Ⅲ型肩锁关节脱位患者,均使用 CHP 复位固定肩锁关节,其中Ⅲ型共20例均未修复喙锁韧带,对比Ⅱ型及Ⅲ型两组患者在取出 CHP 后的疗效。在取出 CHP 后,随访3个月。结果44例患者中有35例患者均在术后1年半内在我科取出 CHP。参照 Karlsson 标准:Ⅱ型组优14例、良4例、差1例,优良率94.7%。Ⅲ型组优12例、良3例、差1例,优良率93.8%。两组优良率差异无统计学意义(P >0.05)。结论 CHP 是目前治疗 Tossy Ⅱ、Ⅲ型肩锁关节脱位的有效方法,对于Ⅲ型急性脱位可不必修复喙锁韧带,愈合后及时取出 CHP 可获得满意的效果。%Objective To investigate the comparative efficacy of clavicular hook plate(CHP)fixation without coracoclavicular ligament repair in the treatment of acute Tossy II and III acromioclavicular dislocation. Methods Forty-four cases of patients with fresh Tossy II and III acromioclavicular dislocation, who were treated by CHP internal fixation from January 2011 to March 2014,were selected. Al of them underwent CHP reduction to fix the acromioclavicular joint. The efficacy of patients from Tossy II group and Tossy III group was compared after CHP removal. The patients were fol owed up for 3 months after CHP removal. Results Of these 44 patients,35 cases removed CHP in our department within one and a half years after surgery.According to Karlsson criteria,there were 14 cases of excel ent grade,4 cases of good grade and 1 case of poor grade in the Tossy II group,indicating an excel ent and good rate of 94.7%. There were 12 cases of excel ent grade,3 cases of good grade and 1 case of poor grade,indicating an excel ent and good rate of 93.8% in the Tossy III group. The

  5. Neglected Traumatic Locked Anterior Shoulder Fracture-Dislocation

    Er, Mehmet Serhan; Eroglu, Mehmet; Erten, Recep Abdullah; Metineren, Hasan; Altinel, Levent

    2015-01-01

    Anterior shoulder dislocations are the most common major joint dislocations encountered in the emergency departments and fractures of proximal humerus can accompany with dislocations. Although the treatment of acute isolated traumatic anterior shoulder dislocation is generally simple, the treatment of neglected fracture-dislocations becomes more complicated. In this report, a 22-year-old male patient who had posttraumatic locked, shoulder fracture-dislocation is presented. Open reduction and ...

  6. 肩关节前脱位坐位复位法及其解剖学基础%Anterior Dislocation of Shoulder Joint Seat reset Method and Its Anatomical Basis

    韩七十三

    2015-01-01

    Objective To study and analysis the anterior dislocation of shoulder joint seat reset method and anatomical basis. Methods According to the clinical work, 27 cases of patients with symptoms of shoulder joint dislocation were under the treatment through seat reset technology by orthopaedic surgeons. Results Through the treatment of shoulder joint dislocation by seat reset method, 25 cases succeeded and 2 cases after two reset successful, this method was effective. Conclusion Shoulder joint relevant anatomy knowledge and master reset technology, was great helpful to improve treatment and anterior dislocation of shoulder joint, seat reset method was worth promoting.%目的:研究分析肩关节前脱位坐位复位法与解剖学基础。方法针对临床工作中的27例具有肩关节脱位症状的患者,骨科医生通过坐位复位技术对其进行治疗。结果通过对肩关节脱位的患者进行坐位复位法治疗,25例一次性就复位成功,另外2例经过两次复位成功,此方法效果显著。结论了解肩关节相关解剖学知识与掌握复位技术,对治疗和改善肩关节前脱位有很大帮助,坐位复位法值得推广。

  7. 37 Cases of Shoulder Joint Dislocation Treatment by Hippocrates Combined with Traditional Chinese Medicine External Treatment%Hippocrates 法结合中药外敷治疗肩关节脱位37例

    穆中杰; 王昌兴

    2014-01-01

    目的:总结运用手牵足蹬手法结合中药外敷治疗37例肩关节脱位的临床疗效。方法:采用手牵足蹬手法结合本科室骨伤熏洗2号方治疗肩关节脱位37例,其中喙突下脱位25例,盂下脱位11例,锁骨下脱位1例;单纯脱位33例,合并肱骨大结节小片撕脱骨折4例,所有患者均根据临床表现和肩关节X线片确诊。结果:本组病例痊愈30例,显效5例,好转2例,总有效率为100%。结论:手法整复结合本院自制骨伤熏洗2号方外敷治疗肩关节脱位疗效可靠,方法简单,经济实惠,值得临床推广。%Objective:to summarize the clinical efficacy of using Hippocrates combined with Chinese medicine external treatment of 37 cases of shoulder joint dislocation .Methods: from April 2012 to February 2013 by Hippocrates combining fractures fumigation Ⅱ in treating of 37 cases whose shoulder joint dislocation ,including 30 cases of male, 7 cases of female; Aged from 15 to 72 years, mean age (36.1 ±4.9) years;The shortest duration after 0.5 h, the longest 3 d;under coronoid process dislocation in 25 cases, jar dislo-cation in 11 cases, subclavian dislocation in 1 case;Pure dislocation in 33 cases, small footprint of the merger of the greater tuberosity avulsion fractures in 4 cases, all patients according to clinical manifestations and shoulder joint X -ray diagnosis.Results: all cases healed 30 cases, accounting for 81.08%;5 cases were markedly improved (13.51%), Improvement in 2 cases, accounting for 5. 41%;0 case ineffective;Total efficiency of 100%.Conclusion:Manual reduction combined with our homemade fractures fumigationⅡreally reliable curative effect , topical treatment of shoulder joint dislocation and the treatment method is simple , economical and practical, is worth popularization and application in the clinical practice .

  8. Subtalar dislocation

    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.)

  9. Subtalar dislocation

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

    1982-05-01

    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.

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

    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

  11. 电子喉镜下喉异物钳治疗环杓关节脱位临床疗效分析%Clinical effect of reposition of cricoarytenoid joint dislocation through foreign body forceps under electronic laryngoscope

    余文兴; 黄红星; 黄远

    2012-01-01

    Objective To explore the operative efficacy and skills of repositing cricoarytenoid joint dislocation through foreign body forceps under electronic laryngoscope. Methods 8 cases of cricoarytenoid joint dislocation caused by gastrointestinal endoscopy, nasogastric tube, tracheal intubation and neck trauma were included in this study. All cases were treated by foreign body forceps under electronic laryngoscope with local anaesthesia. Results Seven cases were re-posited successfully with one time and one case with two times, and their voice were back to normal with a following-up of 6 to 24 months after operation. There were no complications during or after surgery. Conclusion The treatment of cricoarytenoid joint dislocation with foreign body forceps under electronic laryngoscope is simple, safe, and have high success rate, and it may be useful for patients with cricoarytenoid joint dislocation.%目的 探讨经电子喉镜下喉异物钳治疗环杓关节脱位的疗效及复位技巧.方法 8例因上消化道电子内镜检查、鼻饲管、全麻下气管插管、颈部外伤等所致环杓关节脱位患者,在电子喉镜下喉异物钳进行环杓关节复位术.结果 7例1次、1例2次手术复位成功,术后随访6~24个月,声音恢复正常.结论 电子喉镜下喉异物钳进行环杓关节复位方法简单、准确、安全、快速,手术成功率高,在临床上具有一定应用价值.

  12. Simultaneous shoulder and elbow dislocation

    Çobanoğlu, Mutlu; Yumrukcal, Feridun; KARATAŞ, Cengiz; Duygun, Fatih

    2014-01-01

    Ipsilateral shoulder and elbow dislocation is very rare and only six articles are present in the literature mentioning this kind of a complex injury. With this presentation we aim to emphasise the importance of assessing the adjacent joints in patients with trauma in order not to miss any accompanying pathologies. We report a case of a 43-year-old female patient with ipsilateral right shoulder and elbow dislocation treated conservatively. The patient reported elbow pain when first admitted to...

  13. The epidemiology of shoulder dislocations in Oslo

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

    2011-01-01

    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 5...

  14. 手牵足蹬配合呼吸放松疗法治疗肩关节脱位%Hand Drawing and Foot Pedaling with Breathing Relaxation Therapy for the Treatment of Dislocation of Shoulder Joint

    赵亮; 何斌斌; 陈肖; 温清波; 谢增军

    2012-01-01

    Objective To introduce the hand drawing and foot pedaling with breathing relaxation therapy in the treatment of dislocation of shoulder joint. Methods The causes, treatment methods and curative effects of the 89 cases of shoulder joint dislocation were analyzed retrospectively. Results All patients obtained successful reconstruction in acute stage by using the hand drawing and foot pedaling with breathing relaxation therapy. 2 to 8 months' follow - ups demonstrated that all 89 cases obtained clinical union. Conclusion The breathing relaxation therapy could create the most labor - saving opportunity for the reconstruction, and its combination with hand drawing and foot pedaling method could have a notably curative effect on dislocation of shoulder joint.%目的 探讨手牵足蹬配合呼吸放松疗法治疗肩关节脱位的效果.方法 回顾性分析89例肩关节脱位患者的病因、治疗方法和效果.结果 通过手牵足蹬配合呼吸放松疗法治疗肩关节脱位患者89例,脱位均能一次复位成功,随访2~8个月均完全治愈.结论 采用呼吸放松疗法,能够为复位创造最省力的时机,配合手牵足蹬手法治疗肩关节脱位疗效显著.

  15. Developmental Dislocation (Dysplasia) of the Hip (DDH)

    .org Developmental Dislocation (Dysplasia) of the Hip (DDH) Page ( 1 ) The hip is a “ball-and-socket” joint. In a normal hip, the ball at the ... American Academy of Orthopaedic Surgeons. .org Developmental Dislocation (Dysplasia) of the Hip cont. • Family history of DDH (parents or siblings) • ...

  16. A Bilateral Traumatic Hip Obturator Dislocation

    Karaarslan, Ahmet Adnan; Acar, Nihat; Karci, Tolga; Sesli, Erhan

    2016-01-01

    A case of a bilateral simultaneous traumatic obturator dislocation of both hip joints in an 18-year-old young man following a traffic accident is presented. We reduced the dislocated femoral heads immediately under general anesthesia followed by passive and active exercises and early full-weight bearing mobilization. After 5 years, the result was excellent. PMID:26977327

  17. Shoulder Joint Replacement

    ... en because of implant loosening, wear, infection, and dislocation. When this occurs, a second joint replacement surgery — called a revision surgery — may be necessary. Is Shoulder Joint Replacement for You? The decision to have ...

  18. Treatment of children′s heel open injuries with ankle joint dislocation%儿童足跟部开放性损伤伴踝关节脱位的治疗

    王磊; 王平均; 乔少林; 范克轩; 陈翰林; 孟勐; 黄东; 陆欢

    2015-01-01

    Objective To explore the treatment choice and effect of children′s heel open injuries with ankle joint dislocation.Meth-ods 10 cases of children's heel open injuries with ankle joint dislocation were studied.First,each patient underwent exhaustive debridement to the open injuries,with Kirschner wire fixation after the ankle joint dislocation being restored,and then the wounds were covered with dress-ings and VSD (vacuum sealing drainage)was used continuously.Two weeks later,the injured achilles tendons were reconstructed,and ple-rosis of the soft tissue defects were operated by reversed transferring of sural neurovascular fasciocutaneous flap or saphenous nerve nutritional vessels flap.Results The wounds healed well in all cases and the stitches were taken out on schedule.Six weeks after the skin flap repai-ring operation,Kirschner wires were removed and the children started rehabilitation training of ankle joint function.After the follow-up period of 6~16 months,the function of ankle joint was evaluated by Baird-Jackson grading standard:excellent in 7 cases,good in 2 cases,normal in 1 case,bad in 0 cases,with 90.0% excellent rate.The blood supply of all skin flaps was sufficient and the skin color was approximate normal.Conclusion Exhaustive debridement and fixed ankle joint restoration,together with later achilles tendon reconstruction and skin flap repairing operation,is a effective and reasonable treatment choice to children's heel open injuries with ankle joint dislocation.%目的:探讨儿童足跟部开放性损伤伴踝关节脱位的治疗方法和效果。方法10例足跟部开放性损伤伴踝关节脱位患儿急诊清创,踝关节复位后克氏针固定,行负压封闭引流(VSD)覆盖创面;2周后手术重建跟腱、腓肠神经营养血管皮瓣或隐神经营养血管皮瓣逆行转移覆盖软组织缺损创面。结果10例患者皮瓣愈合良好,按期拆线。皮瓣修复术后6周拔除固定踝关

  19. Neglected Anterior Dislocation of Shoulder: is surgery necessary? A Rare Case with review of literature

    Shah, Kunal; Ubale, Tushar; Ugrappa, Harish; Pilankar, Samir; Bhaskar, Atul; Kale, Satishchandra

    2015-01-01

    Introduction: Shoulder joint is the most frequently dislocated joint. However, it is rarely neglected and treatment is sought immediately. Delayed or neglected shoulder dislocations are difficult to manage and require extensive procedures to obtain good functional outcome. Very few cases are described in literature showing neglected shoulder dislocation with good functional range of movement. We report a case with 3 years of neglected anterior shoulder dislocation with preserved joint functio...

  20. Audit on necessity of radiographs in anterior shoulder dislocations

    K. Ahmadi, M.D; M. Mofidi, M.D.

    2008-01-01

    AbstractBackground and Purpose: Anterior shoulder dislocation is the most common major joint dislocation. In most cases, this dislocation is being relocated in emergency departments. Routinely, pre and post reduction radiographs are performed. This study was done to determine the necessity of radiographs in the emergency department for management of patients with suspected anterior shoulder dislocation.Materials and Methods: In this case series study, 116 patients suspected of anterior should...

  1. Hennipen 法治疗老年患者肩关节前脱位的临床疗效观察%Clinical effect of Hennipen method to treat elderly patients with anterior dislocation of the shoulder joint

    陈孙裕; 肖展豪; 李坚

    2016-01-01

    Objective To analyze the clinical curative effect of Hennipen method to treat elderly patients with anterior dislocation of shoulder joint.Methods Between February 2013 and June 2015,57 elderly patients with acute anterior dislocation of shoulder joint were colleted in our hospital.The patients aged from 65 to 81,with average age of 72.3 years.Hennipen method was used to replace the dislocation of shoulder joint.Visual analogue scale (VAS)scores and joint range of motion before and after treatment were recorded to evaluate its clinical effect.Results All cases were checked with X -ray to comfirm had been reducted,and had no complications,such as proximal humeral fractures,axillary nerve injured.1 case failed maneuver reduction,so was tracted and reseted again after anesthesia.Before treatment,the VAS scores was (5.4 ±0.9)points,which after treatment was (1.9 ±0.7)points, and the difference was significant(t =12.43,P <0.01).The range of motion of the shoulder joint was significantly improved.Conclusion Hennipen method is simple,to threat anterior dislocation of shoulder joint of elderly patients, it can effectively relieve pain,reduce complications,which is worthy of clinical promotion.%目的:分析 Hennipen 法治疗老年患者肩关节前脱位的临床疗效。方法收集厦门大学附属福州市第二医院治疗的急性肩关节前脱位老年患者57例,年龄65~81岁,平均72.3岁。所有患者采用Hennipen 法复位肩关节,治疗前后记录肩关节活动度,采用疼痛视觉模拟量表(VAS)评分,评估其临床效果。结果所有患者行 X 线检查,证实整复成功,未出现肱骨近端骨折、腋神经损伤等并发症,1例复位失败,改麻醉下牵引复位。治疗前 VAS 评分为(5.4±0.9)分,治疗后 VAS 评分为(1.9±0.7)分,治疗前后 VAS 评分差异有统计学意义(t =12.43,P <0.01)。治疗后患者关节活动度均明显改善。结论Hennipen 法复

  2. Arthroscopic findings after shoulder dislocation

    Medenica Ivica

    2009-01-01

    Full Text Available Background/Aim. Recurrent instability of the shoulder joint is frequently difficult to differentiate from diseased or injured rotator cuff or tendon of the forearm flexor (m. biceps brachii. Shoulder joint arthroscopy has been only recently introduced into instable shoulder joint lesion examination. The aim of this study was to present and analyze an arthroscopic finding on instable shoulder joint in order to determine causes and mechanisms of instability, as well as principles of surgical treatment. Methods. Arthroscopy of the shoulder joint was performed in 158 patients with at least one documented shoulder joint dislocation. These patients were divided into two groups. The group I included the patients with one to three dislocations, while the group II those with more than three dislocations. Preoperative diagnosis was based on anamnestic data and clinical examination using specific tests, and on the diagnosis of shoulder joint using radiography or computed tomography. Results. Out of the total number of the patients 138 (87.34% had injury of the anterior patellar brim, 119 (75.32% had failure of the anterior capsule, 126 (79.75% had compressive cartilage injury of the posterior part of the head of the upper arm bone (Hill-Sachs lesion, 102 (64.56% had insufficiency of glenohumeral tendon, 11 (6.96 had complete cut of the rotator cuff, 23 (14.56% had injury of the posterior patellar brim, 12 (7.59% had injury of the upper anterior-posterior patellar brim (SLAP. Conclusion. According to the obtained results it could be concluded that there is no a unique injury that leads to shoulder joint instability. It is necessary to point out to the significance of anamnesis and clinical examination in making diagnosis. Arthroscopic diagnostics is indicated in clinically unreliable findings as an additional method for determining operative treatment.

  3. A Case Report: Ipsilateral Closed Talus Dislocation and Navicular Fracture

    Tolga Atay

    2014-02-01

    Full Text Available Dislocation of the subtalar joint dislocations are rare. Three joint axes associated with that (which, tibiotalar, subtalar and talonavicular talus bone dislocation totally high-energy trauma or sports competitions outcome occurs, and this trauma as a result of complications of neurovascular injury, the talus capsular structure damage, skin necrosis and ligament damage may occur. Result of late term complications are avascular necrosis and degenerative arthritis. Talus fractures often are associated with one of the malleolus fracture or dislocation of the talus. Isolated talus dislocations without malleolus and talus fractures are usually occurs in open wounds. In this case, closed talus dislocation and ipsilateral navicular bone of foot fracture are observed as a result of the high energy trauma without malleolar fractures or fracture of the talus. Closed Talus dislocations are rare in the literature and has very less informations.

  4. Lisfranc fracture dislocation. Clinical case

    Lora-Fernández Alberto Carlos; Cabarcas-Montes Gustavo

    2010-01-01

    The Lisfranc fracture dislocation is a serious lesion occur in tarsometatarsian joint and produce importants consequence, for anatomic complexiti of this foot area. The injury mechanisms ocasionality is asociated to automovilistic accidents. Our report of a clinical case into a patient endure fall since 8 meter altitud. Quirurgical manegement was make, open reduction and osteosíntesis with Kirschner nails. Favorable evolution and adecuate reponse to rehabilitation.RESUMENLa luxofractura de Li...

  5. Posterior sternoclavicular dislocation: an American football injury

    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...... 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....

  6. Isolated Proximal Tibiofibular Dislocation during Soccer

    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.

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

    Patro Dilip K; Agarwal Dinesh K; Saseendar S; Menon Jagdish

    2009-01-01

    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 Engl...

  8. 肩关节镜带线锚钉内固定术治疗复发性肩关节脱位%Clinical Research of Arthroscopic Suture Anchor Fixation Treatment with Recurrent Shoulder Joint Dis-location

    沈烈军

    2014-01-01

    目的:探讨肩关节镜下带线锚钉内固定术治疗复发性肩关节脱位的效果。方法:选取复发性肩关节脱位患者76例,随机分为观察组与对照组各38例,观察组采用肩关节镜下带线锚钉内固定术治疗,对照组给予改良Bristow手术治疗。结果:观察组UCLA评分(33.13±1.49)分,VAS评分(0.54±0.49)分,外展90°位外旋角度(73.62±13.98)°,肩关节前屈上举角度为(157.24±17.38)°,优良率97.37%,均优于对照组的78.9%(P<0.05)。结论:肩关节镜下带线锚钉内固定术治疗复发性肩关节脱位,具有良好的应用价值,改善肩关节功能。%Objective To investigate the clinical effects of arthroscopic suture anchor fixation in the treat⁃ment with recurrent shoulder joint dislocation. Methods A total of 76 patients were included in study, were divided into observation group and control group randomly. Observation group were treated with arthroscopic su⁃ture anchor fixation, control group were treated with improved surgical bristow. Results In observation group after surgery, the UCLA score was (33.13±1.49), the VAS score was (0.54±0.49), the abduction and external rota⁃tion angle of 90° position was (73.62±13.98)°, the shoulder flexion angle was (157.24±17.38)°, the excellent rate was 97.37%. All indicators had significant differences compared with control group (P<0.05). Conclusion These results suggest that recurrent shoulder joint dislocation in the treatment of arthroscopic suture anchor fixa⁃tion has the exact value, can improve joint function.

  9. Application of MSCT and MRI in diagnosing Bankart injury of recurrent anterior dislocation of shoulder joint%MSCT、MRI联合运用在复发性肩关节前脱位Bankart病损中的应用价值

    易雪冰; 张德洲; 钟鉴

    2011-01-01

    目的:探讨MSCT、MRI联合运用在复发性肩关节前脱位Bankart病损中的应用价值.方法:回顾性分析经临床、影像证实的复发性肩关节前脱位Bankart病损10例患者的MSCT、MRI表现,主要观察肩关节盂唇前方的CT、MRI改变.结果:10例中,CT发现肩关节盂前下份撕脱性骨折4例,MRI发现肩关节前下盂唇撕脱性骨折1例;MRI发现肩关节盂唇损伤10例,CT不能显示;CT发现合并Hill-Sachs损伤6例,MRI发现Hill-Sachs损伤8例;CT未能发现肱骨头骨挫伤3例;MRI发现肩袖损伤6例,Slap损伤1例.结论:MSCT、MRI能够相互补充,清晰显示Bankart病损及其他合并病变,为临床诊断及治疗提供更加充分的资料.%Objective : To investlgate the application of MSCT and MRI in B ankart injury of recurrent anterior dislocation of shoulder joint Methods :Retrospectively analyse 10 cases Bankart injury of recurrent anterior dislocatlon of shoulder joint by clinic and radiology.Analysed the manifestations of shoulder joint an terior labrum articularis of spiralCT and MRI.Results : In 10 cases of Bankart injury of recurrent an terior dislocation of shoulder pint , there were 4 cases of avulsion fiacture of shoulder pint anterior labrum examined by CT , 1 case by MRI; 6 cases of Hill-Sachs injury were found examined by CT , 8 cases of Hill-Sachs injury and 3 cases of bone contusion of hum eralhead were found by MRI; 6 cases of rotator cuff injury and 1 case of slap injury were found exam ined by MRI.Conclusion :Spial CT and MRI can display Bankart injury and other coexisting lesion , which provide sufficient data for the clinic.

  10. 伴有骶髂关节完全性前脱位的骨盆骨折治疗%Management of pelvic injury associated with complete anterior sacroiliac joint dislocation

    吴宏华; 吴新宝; 李宇能; 杨明辉; 王满宜

    2015-01-01

    Objective:To investigate the management of pelvic injury associated with complete anterior sacroiliac joint dislocation.Methods:In the study, 6 cases of pelvic injury associated with complete an-terior sacroiliac joint dislocation treated in Beijing Jishuitan Hospital from February 2008 to June 2014 were analyzed.We described the history and severity of injury, emergency treatment, and fracture radio-logy.In all the cases, the surgical treatment and postoperative functional exercise were performed.We followed up all the cases on an average of 1.6 years, assessed the postoperative recovery and summed up the treatment experience.Results:All the 6 patients with fractures recovered without infection and nerve symptoms after surgery.Their X-rays showed good reduction of sacroiliac joints.All the cases were followed up on an average of 1.6 years.Six months after surgery, the Majeed scores were perfect in 2 cases, good in 2, fair in 1, and poor in 1.The patients with poor scores suffered persistent pain, and decreased physical activity, and when walking long distances, they needed a walking stick.The 2 patients with low scores could not resume the original work.Conclusion:Pelvic injury associated with complete anterior sacroiliac joint dislocation is a special type of the pelvic injury since the managements during the emergency phase are difficult.The surgery should be done as early as possible, and the anterior approach is available for the reduction and fixation.%目的:总结伴有骶髂关节完全性前脱位的骨盆骨折的治疗经验。方法:对北京积水潭医院2008年2月至2014年3月收治的6例伴有骶髂关节完全性前脱位骨盆骨折的资料进行回顾性分析,描述患者病史、损伤程度、急诊救治等特征,通过影像学判断损伤情况,给予手术治疗,术后功能锻炼,并对患者进行随访以评估术后恢复情况,总结治疗经验。结果:全部6例患者术后愈合良好,无感染和术后

  11. Clinical research on humerus surgical neck fracture joint shoulder dislocation%肱骨外科颈骨折并肩关节脱位的临床研究

    钟泽林; 陈琦翔

    2013-01-01

      目的:研究手术治疗肱骨外科颈骨折合并肩关节脱位的有效方法。方法:按照计算机数字表法将99例肱骨外科颈骨折合并肩关节脱位患者随机分为A、B、C三组,各33例,A组采用切开交叉克氏内固定治疗,B组采用切开钢板内固定治疗,C组采用切开外展支架固定治疗,比较三组患者术后3、7、14d VAS评分,比较患者下床活动时间、骨折愈合时间、平均治疗费用、并发症发生率,术后6个月肩关节功能。结果:A组患者术后3、7、14d明显低于B组和C组,组间比较差异具有统计学意义(P<0.05)。A组患者下床时间、骨折愈合时间、平均治疗费用、并发症发生率均低于B组和C组,Neer评分高于B组和C组,组间比较差异具有统计学意义(P<0.05)。结论:切开交叉克氏内固定治疗手法闭合整复失败的肱骨外科颈骨折合并肩关节脱位患者具有骨折愈合快,治疗成本和并发症发生率低等优点,可优先选用。%Objective:To study the effective method of treating humerus surgical neck fracture joint shoulder dislocation. Methods:According to the computer digital table method, 99 patients of humerus surgical neck fracture joint shoulder dislocation were randomly divided into A, B, C three groups, 33 in each group. Group A was given crossed-pin interior fixation, Group B was given open reduction and internal fixation, Group C was given open reduction upper limbs abducens support fixed treatment. Compare VAS scores in three groups postoperative 3, 7, 14 days, out-of-bed activity time, fracture healing time, average treatment costs, complications, and postoperative 6 months of shoulder joint function. Results:VAS scores in group A postoperative 3, 7, 14 days were obviously lower than that in group B and group C, with significant differences (P<0.05). Group A has lower bed time, fracture healing time, average treatment costs and complication rate were

  12. CHP和TB两种内固定方式治疗Tossy Ⅲ型肩锁关节脱位的疗效比较%Clinical effects of CHP and TB in treatment of Tossy Ⅲ type acromioclavicular joint dislocation

    孙泰岩

    2010-01-01

    目的:比较锁骨钩钢板(clavicular hook plate,CHP)与克氏针张力带(tension band,TB)治疗Tossy Ⅲ型肩锁关节脱位的临床疗效.方法:选择Tossy Ⅲ型肩锁关节脱位患者78例,根据自愿原则,其中42例使用CHP治疗,作为观察组;36例使用TB治疗,作为对照组.比较两组治疗5个月后肩关节功能及术后并发症情况.结果:观察组与对照组术后并发症比较,差异有统计学意义(P<0.05);肩关节功能恢复在优良方面两组比较,差异有统计学意义(P<0.05).结论:CHP治疗创伤小,疗效确切,并发症少,应作为治疗Tossy Ⅲ型肩锁关节脱位的首选方法.

  13. 改良椅背复位法治疗肩关节脱位的效果分析%Improved Chair Back Reduction Method for the Treatment of Dislocation of the Shoulder Joint Effect Analysis

    王顺兴; 陈远宁

    2013-01-01

    目的:通过用经过改良后的椅背复位法来治疗肩关节脱位,对治疗效果进行分析。方法:86例肩关节脱位患者随机分为两组,分别为改良组合未改良组。改良组的患者采用改良后的椅背复位法来治疗肩关节脱位,而未改良组采用传统的椅背复位法来治疗。治疗结束后,对两组患者的复位成功率、患者满意度进行统计调查。对两种方法进行评价分析。结果:治疗结束后,调查统计结果显示,改良组的1次性复位成功为42例,成功率为97.7%,2次复位成功为1例,成功率为2.3%;未改良组的一次性复位成功为31例,成功率为72.1%,2次复位成功为12例,成功率为27.9%。患者的满意度情况为,改良组的41例满意,满意度为95.3%,未改良组满意35例,满意度81.4%,以上统计P均小于0.05。结论:经过改良的椅背复位法治疗肩关节脱位的一次性治愈率高于未经改良组的患者,且满意度也高于未经改良组。%Objective:By using the improved method to reset back after treatment of shoulder dislocation, the treatment effect analysis. Methods:86 cases of shoulder joint dislocation were randomly divided into two groups, respectively, for improved combination of unimproved group. The modified group of patients using a modified back reset method to the treatment of shoulder dislocation, without improvement group using the traditional back reset method to treatment of. After the end of treatment, two groups of patients with the success rate reduction, patient satisfaction survey. On two methods for evaluation and analysis. Results:After treatment, the survey results show the modified group, 1 reduction for the success of 42 cases, the success rate was 97.7%, 2 reduction was successful for 1 patients, the success rate is 2.3%;unimproved group disposable reset successfully for 31 patients, the success rate was 72.1%, 2 reset successfully for 12 cases, the success rate is 27.9%. Patient

  14. Medial subtalar dislocation: Case report

    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.

  15. Hip joint replacement

    ... may have problems with infection, loosening, or even dislocation of the new hip joint. Over time the artificial ... Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, ...

  16. Treatment Zygapophyseal Joints Dislocation of Inferior Thoracic Vertebra with Fixed-Point Oblique-Pulling Manipulation: A Report of 124 Cases

    JIN Cheng-zhong; LANG Bo-xu; FANG Zhen-yu; ZHU Han-ting

    2004-01-01

    以推拿手法治疗124例下胸椎关节突关节错位患者,先以滚揉松肌法和痛点弹拨法松解痛处肌肉,然后以定点斜扳整复法理筋平压法纠正关节错位,治疗3次后治愈94例,好转21例,未愈9例,总有效率为92.7%.%One hundred and twenty-four cases of articulations zyqapophysiales discocation of the inferior thoracic vertebra were treated first with Tuina manipulation of rolling-kneading to relax the affected muscles, next with that of tenderness-plucking to relax the tender muscles and next with that of fixed-point oblique-pulling to restore and treat the injured soft tissues and finally with that of palmpressing flatly to adjust the dislocation. The results showed that 94 cases were cured, 21 improved and 9 ineffective after three treatments. The total effective rate was 92.7 %.

  17. EFFECTIVENESS OF TRAUMATIC DISLOCATION OF KNEE JOINT COMBINED WITH MULTIPLE LIGAMENT INJURIES TREATED BY STAGES%分期治疗外伤性膝关节脱位合并多韧带损伤的疗效观察

    陈志伟; 刘春磊; 杨乐忠; 戴祝; 曹盛俊

    2011-01-01

    目的 观察分期治疗外性伤膝关节脱位合并多韧带损伤的临床疗效. 方法 2005年6月-2008年11月,收治13例外伤性膝关节脱位合并多韧带损伤患者.男9例,女4例;年龄18~54岁,平均30.7岁.致伤原因:运动伤8例,交通事故伤2例,高处哈落伤2例,扭伤1例.左侧3例,右侧10例.受伤至入院时间6 h~2 d,平均9h.8例前交叉韧带(anterior cruciate ligament,ACL)、后交叉韧带(posterior cruciate ligament,PCL)及内侧副韧带(medial collateral ligament,MCL)损伤,3例ACL、PCL及外侧副韧带(lateral collateral ligament,LCL)损伤,2例ACL、PCL、MCL及LCL损伤.10例外翻应力试验为++~+++,5例内翻应力试验为++~+++;13例前、后抽屉试验均为阳性,Lachman试验为++~+++.一期手术修复PCL、MCL、LCL及半月板,术后固定3~4周后开始功能锻炼,4~6个月后膝关节活动范围良好且存在前方不稳时二期于关节镜下重建ACL. 结果 两次手术后切口均Ⅰ期愈合,无感染及骨筋膜室综合征等并发症发生.患者均获随访,随访时间12~60个月,平均36个月.一期术后4周2例出现关节腔积液,经穿刺抽吸后缓解,其余患者均未出现膝关节不适.二期术后3个月1例外翻应力试验++,1例为+;1例内翻应力试验为+;1例Lachman试验++,1例为+;其余患者各试验均为阴性.二期术后12个月患膝关节屈曲达100~135°,平均123.4°;伸直达0~4°,平均2.3°.根据Lysholm膝关节功能评分标准评定:获优9例,良2例,可2例,优良率84.6%. 结论 分期治疗外伤性膝关节脱位合并多韧带损伤可获得较好的临床效果.%Objective To observe the effectiveness of traumatic dislocation of the knee joint combined with multiple ligament injuries treated by stages. Methods Between June 2005 and November 2008, 13 cases of traumatic dislocation of the knee joint combined with multiple ligament injuries were treated by stages, including 9 males and 4 females with an average age of 30

  18. Dislocated shoulder - aftercare

    Shoulder dislocation - aftercare; Shoulder subluxation - aftercare; Shoulder reduction - aftercare ... Horn AE, Ufberg JW. Management of common dislocations. In: ... Extremity 6th ed. Philadelphia, PA: ElsevierMosby; 2011:chap 92.

  19. Dislocated shoulder - aftercare

    Shoulder dislocation - aftercare; Shoulder subluxation - aftercare; Shoulder reduction - aftercare ... You most likely dislocated your shoulder from a sports injury or accident, such as a fall. You have likely injured (stretched or torn) some of the muscles, ...

  20. Distal clavicle osteolysis following fixation with a synthetic ligament

    Paul M.C Dearden

    2011-01-01

    Full Text Available We present a case of distal clavicle osteolysis following treatment of a chronic acromioclavicular joint dislocation with a synthetic ligament. The relevant literature is reviewed and discussed.

  1. Simultaneous shoulder and elbow dislocation

    Çobanoğlu, Mutlu; Yumrukcal, Feridun; Karataş, Cengiz; Duygun, Fatih

    2014-01-01

    Ipsilateral shoulder and elbow dislocation is very rare and only six articles are present in the literature mentioning this kind of a complex injury. With this presentation we aim to emphasise the importance of assessing the adjacent joints in patients with trauma in order not to miss any accompanying pathologies. We report a case of a 43-year-old female patient with ipsilateral right shoulder and elbow dislocation treated conservatively. The patient reported elbow pain when first admitted to emergency service but she was diagnosed with simultaneous ipsilateral shoulder and elbow injury and treated conservatively. As a more painful pathology may mask the additional ones, one should hasten to help before performing a complete evaluation. Any harm caused to the patient due to this reason would not be a complication but a malpractice. PMID:24859563

  2. Joint-sparing Corrections in Malunited Lisfranc Joint Injuries.

    Nery, Caio; Raduan, Fernando; Baumfeld, Daniel

    2016-03-01

    Lisfranc fracture-dislocations are very serious and potentially disabling injuries. Unfortunately, they are often misdiagnosed. Multiplanar midfoot deformities that result from these fracture-dislocations are precursors of joint degeneration and significant functional disabilities. Anatomic reduction with different types of internal fixation is an efficient method to reconstruct midfoot alignment and stability. Joint-preserving reconstruction techniques emerge as a viable alternative to corrective fusion as they achieve stable joint realignment with preserved motion. PMID:26915786

  3. Glenoid Dysplasia in the Recurrent Shoulder Dislocation: A Case Report

    Hamza Sucuoglu

    2016-01-01

    Glenoid dysplasia, which is often ignored, is a rare developmental anomaly. In most cases the patients remain asymptomatic. Although glenoid dysplasia has been diagnosed by incidentally on chest radiograph, also it has been described because of the developing instability of shoulder joint. Our young male patient who has recurrent dislocation of the shoulder-joint 4-5 times a year for last 5 years, dislocation has been reduced in the emergency department and he has been discharged from hospita...

  4. Scapular manipulation technique for reduction of traumatic anterior shoulder dislocations: experiences of an academic emergency department

    Baykal, B; Sener, S; Turkan, H

    2005-01-01

    Background: Shoulder dislocations account for almost 50% of all joint dislocations, which are most commonly anterior (90–98%) and occur due to trauma. This prospective study was conducted to report our experiences of using the scapular manipulation technique (SMT) to reduce traumatic anterior shoulder dislocations.

  5. The gauge theory of dislocations: A nonuniformly moving screw dislocation

    Lazar, Markus, E-mail: lazar@fkp.tu-darmstadt.d [Emmy Noether Research Group, Department of Physics, Darmstadt University of Technology, Hochschulstr. 6, D-64289 Darmstadt (Germany); Department of Physics, Michigan Technological University, Houghton, MI 49931 (United States)

    2010-07-05

    We investigate the nonuniform motion of a straight screw dislocation in infinite media in the framework of the translational gauge theory of dislocations. The equations of motion are derived for an arbitrarily moving screw dislocation. The fields of the elastic velocity, elastic distortion, dislocation density and dislocation current surrounding the arbitrarily moving screw dislocation are derived explicitly in the form of integral representations. We calculate the radiation fields and the fields depending on the dislocation velocities.

  6. A hinged external fixator for complex elbow dislocations: A multicenter prospective cohort study

    Verleisdonk Egbert JMM; Van Vugt Arie B; Van Thiel Tom PH; Van der Meulen Hub GWM; Sintenie Jan; Schipper Inger B; Roukema Gert R; Rhemrev Steven; Ham S John; Goslings J Carel; De Vries Mark R; Bronkhorst Maarten WGA; Tuinebreijer Wim E; Iordens Gijs IT; de Haan Jeroen

    2011-01-01

    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 of the radial head, olecranon, or coronoid process. The majority of patients with these complex dislocations are treated with open reduction and internal fixation (ORIF), or arthroplasty in case of a non-reconstructable radial head fracture. If the elbow joint remains unstable after fracture f...

  7. The external rotation method for reduction of acute anterior shoulder dislocations

    Marinelli, Mario; de Palma, Luigi

    2009-01-01

    Background Shoulder dislocations account for almost 50% of all joint dislocations, and are most commonly anterior (90–98%) and occur due to trauma. This prospective study was conducted to report our experiences of using the external rotation method (ERM) in the reduction of acute anterior shoulder dislocation. Materials and methods Between August 2006 and April 2007, ERM was applied to 31 patients who presented with traumatic anterior shoulder dislocation to the Emergency Department of our Ho...

  8. Ipsilateral fracture dislocation of the shoulder and elbow: A case report and literature review

    Behr, Ian; Blint, Andy; Trenhaile, Scott

    2013-01-01

    Ipsilateral dislocation of the shoulder and elbow is an uncommon injury. A literature review identified nine previously described cases. We are reporting a unique case of ipsilateral posterior shoulder dislocation and anterior elbow dislocation along with concomitant intra-articular fractures of both joints. This is the first report describing this combination of injuries. Successful treatment generally occurs with closed reduction of ipsilateral shoulder and elbow dislocations, usually reduc...

  9. Audit on necessity of radiographs in anterior shoulder dislocations

    K. Ahmadi, M.D

    2008-01-01

    Full Text Available AbstractBackground and Purpose: Anterior shoulder dislocation is the most common major joint dislocation. In most cases, this dislocation is being relocated in emergency departments. Routinely, pre and post reduction radiographs are performed. This study was done to determine the necessity of radiographs in the emergency department for management of patients with suspected anterior shoulder dislocation.Materials and Methods: In this case series study, 116 patients suspected of anterior shoulder dislocation were referred to Hazrat Rasoul Akram and Haftome Tir Hospitals emergency departments in Tehran, and were investigated for a one year period. The emergency physicians evaluated and documented the possibility of dislocation or relocation, before obtaining radiographs. Outcome measures were the assessment of joint positions on the x-rays by an orthopedic surgeon.Results: 84 cases (72% were male and 32 cases (28% were female. Mean age of the patients was 31.5±8.5 yrs. Thirty (30 patients had recurrent dislocations without traumatic mechanism (group 1 and eighty six (86 patients had no prior dislocation or a blunt mechanism of injury (group 2. The accuracy of the emergency physician’s assessment in dislocations was 100% in group 1 and 98% in group 2. False assessments occurred only in patients with fractures. There is no significant difference between emergency physicians and orthopedic surgeons in the assessment of dislocations and relocations, when the emergency physicians did accuralty diagnose them.Conclusion: Our study showed that the physicians are highly accurate in clinical determination of anterior shoulder dislocation and relocation. Pre-reduction films should be obtained when the mechanism of injury is trauma. Post-reduction films should be obtained in fracture-dislocations or when the physicians are uncertain of correct relocation.

  10. Akut akromioklaviküler eklem çıkıklarında endobutton ile tesbit yöntemi

    Raif Özden; Vedat Uruç; İbrahim Gökhan Duman; Yunus Doğramacı; Aydıner Kalacı; Erkam Kömürcü

    2014-01-01

    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 classifica...

  11. Dislocation Formation in Alloys

    Minami, Akihiko; Onuki, Akira

    2006-05-01

    An interaction between dislocations and phase transitions is studied by a phase field model both in two and three dimensional systems. Our theory is a simple extension of the traditional linear elastic theory, and the elastic energy is a periodic function of local strains which is reflecting the periodicity of crystals. We find that the dislocations are spontaneously formed by quenching. Dislocations are formed from the interface of binary alloys, and slips are preferentially gliding into the soft metals. In three dimensional systems, formation of dislocations under applied strain is studied in two phase state. We find that the dislocation loops are created from the surface of hard metals. We also studied the phase separation above the coexisting temperature which is called as the Cottrell atmosphere. Clouds of metals cannot catch up with the motion of dislocations at highly strained state.

  12. Dislocation-dynamics method

    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)

  13. Collective behavior of dislocations

    Deformation of a crystal involves the motion of dislocations. Since dislocations interact, a short range and at long range, it is basic to understanding plasticity to establish if dislocations move singly or collectively. If deformation involves the collective motion of dislocations how does it manifest itself or equivalently how can it be measured? While a variety of techniques measure the positions of single dislocations before and after a stress is applied to a crystal, giving an average dislocation velocity, these techniques do not related directly to what happens during deformation, that is the collective behavior of dislocations. The mobile dislocation density is measured as follows: Lead-10% indium crystals are deformed at 4.2K, while in a magnetic field in the range Hc1 c2 where Hc1 is the lower critical field, H the applied field and Hc2 the upper critical field. During deformation changes n the flux are observed; the changes in flux are proportional to the mobile dislocation density. These changes in flux show the following characteristics: When the deformation process changes from elastic to plastic deformation there is a pronounced increase in flux noise, well above the background noise level. In addition superposed on this noise are pronounced bursts of magnetic flux, corresponding to dislocation bursts or avalanches of dislocations. A number of checks establish that these pulses are solely related to dislocations. These include the fact that they are not reproducible in terms of time from test to test, ruling out systematic instabilities in the circuit. Also, they occur when the crystal is unloaded and then reloaded at times, after plasticity is reinitiated, which are inconsistent with any time constant of the circuit. Finally, the measuring circuit shows no instabilities or ringing in this frequency range

  14. Primary traumatic patellar dislocation

    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.

  15. Homogenization of dislocation dynamics

    In this paper we consider the dynamics of dislocations with the same Burgers vector, contained in the same glide plane, and moving in a material with periodic obstacles. We study two cases: i) the particular case of parallel straight dislocations and ii) the general case of curved dislocations. In each case, we perform rigorously the homogenization of the dynamics and predict the corresponding effective macroscopic elasto-visco-plastic flow rule.

  16. Homogenization of dislocation dynamics

    El Hajj, Ahmad; Ibrahim, Hassan; Monneau, Regis, E-mail: elhajj@cermics.enpc.fr, E-mail: ibrahim@cermics.enpc.fr, E-mail: monneau@cermics.enpc.fr [CERMICS, ENPC, 6 and 8 avenue Blaise Pascal, Cite Descartes, Champs sur Marne, 77455 Marne-la-Valle Cedex 2 (France)

    2009-07-15

    In this paper we consider the dynamics of dislocations with the same Burgers vector, contained in the same glide plane, and moving in a material with periodic obstacles. We study two cases: i) the particular case of parallel straight dislocations and ii) the general case of curved dislocations. In each case, we perform rigorously the homogenization of the dynamics and predict the corresponding effective macroscopic elasto-visco-plastic flow rule.

  17. Do normal hips dislocate?

    Alshameeri, Zeiad; Rehm, Andreas

    2014-11-01

    There have been a small number of case reports describing late normal-hip dislocations in children who were later diagnosed with developmental dysplasia of the hip. Here, we contest the assumption that normal hips can dislocate. We argue that (as in our case) the ultrasound scans in all published case reports on late dislocated normal hips did not show results that were entirely normal and therefore, so far, there has been no convincing evidence of a dislocation of a normal hip. We also want to highlight the importance of meticulous ultrasound and clinical assessments of high-risk children by an experienced orthopaedic surgeon. PMID:25144883

  18. Dislocations in yttrium orthovanadate

    Eakins, D. E.; LeBret, J. B.; Norton, M. G.; Bahr, D. F.

    2004-06-01

    Dislocation structures in single crystals of yttrium orthovanadate have been identified by transmission electron microscopy. Electron diffraction was used to predict possible Burgers vectors for the dislocations. Results suggest vectors of the type {1}/{2}[1 1 1] or {1}/{4}[0 2 1] . Arguments for the likelihood of each possible vector have been presented.

  19. Double dislocation of finger interphalangeal joints

    Jahangiri, Saqib Aziz; Mestha, Prabhakar; McNally, Scarlett

    2012-01-01

    A 62-year-old, right-hand-dominant man who had dementia and lived in an Elderly Mentally Infirm (EMI) nursing home was admitted through Accident & Emergency (A&E) department following unwitnessed injury to the left little finger.

  20. 肩关节镜下应用带线锚钉内固定方法治疗复发性肩关节脱位%Arthroscopic Application with Anchor Fixation Method in the Treatment of Recurrent Dislocation of the Shoulder Joint

    周吉湘

    2013-01-01

    Objective To explore the effect of arthroscopic application with anchor fixation method in the treatment of recurrent dislocation of the shoulder joint. Methods 80recurrent dislocation of the shoulder joint patients were randomly divided into 2 groups,control group were treated conservatively, the observation group routine arthroscopic operation treatment.Observation of effect of operation and clinical indexes. Results The total efficiency of the observation group 95%,better than the control group,with significant difference. Conclusion Effect of arthroscopic application with anchor fixation method in the treatment of recurrent dislocation of the shoulder joint is significant.%  目的探讨肩关节镜下应用带线锚钉内固定方法治疗复发性肩关节脱位的疗效。方法将在我院治疗的80名复发性肩关节脱位随机分为2组,常规组40例进行保守治疗,观察组40例行关节镜手术治疗。观察手术效果等临床指标。结果观察组总有效率为95%,优于常规组82.5%,差异有统计学意义(P<0.05)。结论肩关节镜下应用带线锚钉内固定方法治疗复发性肩关节脱位的疗效显著。

  1. Glenoid Dysplasia in the Recurrent Shoulder Dislocation: A Case Report

    Hamza Sucuoglu

    2016-02-01

    Full Text Available Glenoid dysplasia, which is often ignored, is a rare developmental anomaly. In most cases the patients remain asymptomatic. Although glenoid dysplasia has been diagnosed by incidentally on chest radiograph, also it has been described because of the developing instability of shoulder joint. Our young male patient who has recurrent dislocation of the shoulder-joint 4-5 times a year for last 5 years, dislocation has been reduced in the emergency department and he has been discharged from hospital with shoulder strap and rest. Finally when he admitted to our outpatient clinic with recurrent shoulder dislocation, the diagnosis of glenoid dysplasia is revealed by X-ray examination. We present the diagnose of glenoid dysplasia with clinical and radiological findings which should be kept in mind in patients with recurrent dislocations of shoulder as in our case.

  2. Tamponade following sternoclavicular dislocation surgical fixation.

    Bensafi, H; Laffosse, J-M; Taam, S A; Molinier, F; Chaminade, B; Puget, J

    2010-05-01

    The authors report a case of posterior sternoclavicular dislocation surgically reduced and stabilized with tenodesis, according to the Burrows technique completed by temporary wire fixation. The patient presented postoperative pericardiac tamponade appearing progressively from brachiocephalic blood vessels bleeding. Emergency drainage was surgically placed associated with removal of the material, thus curing the patient. This complication, although exceptional, formally contraindicates the use of wire fixation in surgery of the sternoclavicular joint. PMID:20488152

  3. Irreducible lateral dislocation of the elbow.

    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.

  4. Humeral shaft fracture with ipsilateral shoulder dislocation

    Behera Prateek; Kumar Vishal; Aggarwal Sameer

    2014-01-01

    【Abstract】Although fracture of the humeral shaft or dislocation of the shoulder joint is a common injury, a simutaneous injury is rare. We present such a case combined with head injury which took precedence over the skeletal injuries. The postoperative rehabilitation was slowed down by the head injury. This case report makes us aware of some problems when managing the patient with this rare injury and helps us understand the management options better. Also the need for proper follow-up ...

  5. Luxatio erecta: Inferior glenohumeral dislocation

    Baba Asif; Bhat Javid; Paljor S; Mir Naseer; Majid Suhail

    2007-01-01

    Inferior dislocation of the shoulder, also called luxatio erecta, is a rare form of the otherwise common shoulder dislocation. It accounts for less than 0.5% of all shoulder dislocations. A case involving the inferior dislocation of the shoulder is reported. A brief review of the presentation and management of the condition is described.

  6. Luxatio erecta: Inferior glenohumeral dislocation

    Baba Asif

    2007-01-01

    Full Text Available Inferior dislocation of the shoulder, also called luxatio erecta, is a rare form of the otherwise common shoulder dislocation. It accounts for less than 0.5% of all shoulder dislocations. A case involving the inferior dislocation of the shoulder is reported. A brief review of the presentation and management of the condition is described.

  7. Efficacy Analysis of Elbow Flexion and Shoulder Squaring Method as well as Hand Pulling and Foot Pedaling Method on Shoulder Joint Dislocation%屈肘肩顶法与手牵足蹬法治疗肩关节脱位的疗效分析

    陈洁; 姜为民; 李雪峰; 梁林; 刘义杰

    2014-01-01

    目的:比较屈肘肩顶法与手牵足蹬法对于复位肩关节脱位的疗效。方法2012年1月~2012年12月,共治疗肩关节前脱位72例,常规运用了两种手法复位治疗方法,将其分为两组,分别采用屈肘肩顶法(n=36)和手牵足蹬法(n=36)复位。结果采用屈肘肩顶法有6例首次复位失败,采用手牵足蹬法有10例首次复位失败,最终所有患者肩关节功能恢复佳。2组治疗方法比较,屈肘肩顶法较手牵足蹬法复位效率更高,但肩关节功能和活动度恢复无明显差别。结论屈肘肩顶法和手牵足蹬法治疗肩关节前脱位均可获得较好的肩关节功能和活动度,而屈肘肩顶法在复位成功率方面具有优越性,值得临床推广。%Objective To compare the two methods of shoulder joint dislocation therapy as elbow flexion and shoulder squaring, and the therapy of hand pulling and foot pedaling. Methods By two conservative therapies, we treated 72 patients with shoulder joint dislocation who were divided into two groups as 36 patients taking elbow flexion and shoulder squaring method and 36 patients taking hand pulling and foot pedaling method from January to December in 2012. Results There were 6 patients with failure of restoration of shoulder dislocation by first time through elbow flexion and shoulder squaring method, and 10 patients through hand pulling and foot pedaling. Finally, shoulder joints of all patients got well. Hand pulling and foot pedaling method was better than elbow flexion and shoulder squaring method by comparing on restoration of shoulder joint dislocation, but no significant differences on shoulder function and action. Conclusion Either elbow flexion and shoulder squaring or hand pulling and foot pedaling has good shoulder joint function and action. But elbow flexion and shoulder squaring method is superior in restoration of shoulder joint dislocation, which is worth to popularization.

  8. 手法治疗肩关节脱位并发症的早期预防及护理%Early prevention and nursing of complications of shoulder joint dislocation patients treated by manual therapy

    程俊阳; 张凤清; 方军

    2016-01-01

    总结了手法治疗肩关节脱位并发症的早期预防和护理方法,为进一步探讨有效的肩关节脱位并发症防治手法提供借鉴。%It summarized the early prevention and nursing of complications of shoulder j oint dislocation patients treated by manual therapy,so as to further provide references for the effective preventions and treatment of complications of patients with shoulder j oint dislocation.

  9. GPU accelerated dislocation dynamics

    Ferroni, Francesco; Tarleton, Edmund; Fitzgerald, Steven

    2014-09-01

    In this paper we analyze the computational bottlenecks in discrete dislocation dynamics modeling (associated with segment-segment interactions as well as the treatment of free surfaces), discuss the parallelization and optimization strategies, and demonstrate the effectiveness of Graphical Processing Unit (GPU) computation in accelerating dislocation dynamics simulations and expanding their scope. Individual algorithmic benchmark tests as well as an example large simulation of a thin film are presented.

  10. Acute traumatic patellar dislocation.

    Duthon, V B

    2015-02-01

    Inaugural traumatic patellar dislocation is most often due to trauma sustained during physical or sports activity. Two-thirds of acute patellar dislocations occur in young active patients (less than 20 years old). Non-contact knee sprain in flexion and valgus is the leading mechanism in patellar dislocation, accounting for as many as 93% of all cases. The strong displacement of the patella tears the medial stabilizing structures, and notably the medial patellofemoral ligament (MPFL), which is almost always injured in acute patellar dislocation, most frequently at its femoral attachment. Lateral patellar glide can be assessed with the knee in extension or 20° flexion. Displacement by more than 50% of the patellar width is considered abnormal and may induce apprehension. Plain X-ray and CT are mandatory to diagnose bony risk factors for patellar dislocation, such as trochlear dysplasia or increased tibial tubercle-trochlear groove distance (TT-TG), and plan correction. MRI gives information on cartilage and capsulo-ligamentous status for treatment planning: free bodies or osteochondral fracture have to be treated surgically. If patellar dislocation occurs in an anatomically normal knee and osteochondral fracture is ruled out on MRI, non-operative treatment is usually recommended. PMID:25592052

  11. 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

    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

  12. The Control Study of Treatment for Shoulder Joint Dislocation by Abduction, Lifting, Push and Squeeze%外展上举旋转推挤法治疗肩关节脱位的对照研究

    陈巍; 李彬; 李宣隆; 汪永泉; 吴滨

    2015-01-01

    目的:比较外展上举推挤法和手牵足蹬复位法治疗肩关节脱位的疗效,探索一种更加安全、有效的复位手法。方法2011年7月至2014年7月,收治肩关节前脱位患者123例,年龄19~82岁,其中120例按随机数字表法分为A组(实验组60例)和B组(对照组60例)。实验组采用外展上举推挤复位法;对照组采用传统手牵足蹬复位法,余3例同时伴有其他部位损伤或特殊类型脱位而不能采用Hippocrates复位者为C组,直接采用外展上举推挤法。结果对照组60例成功复位56例,1例导致医源性外科颈骨折而最终改为手术治疗,3例复位不能而采用外展上举推挤法后成功复位;实验组共60例均完成良好复位。结论外展上举推挤法整复肩关节脱位成功率高,患者痛苦少,复位方法易掌握,尤其对Hippocrates法不能成功复位者仍能取得较好复位效果。%Objective To compare the clinical effect between abduction, lifting, push and squeeze method and Hippocrates, explore a safer and more effective way of replacement for shoulder joint dislocation. Methods From July 2011 to July 2014, 123 patients with anterior dislocation of shoulder joint, ranging in age from 19 to 82.The patients were randomly divided into group A (treatment group, 60 cases) and group B (control group, 60 cases). Treatment group were treated by abduction, lifting, push and squeeze. Control group were treated with Hippocrates. The other three cases with other injuries and special dislocation were put in group C, and they were treated by abduction, lifting, push and squeeze directly. Results 56 patients in control group got replacement.1 patient was operated

  13. Statistical characterization of dislocation ensembles

    El-Azab, A; Deng, J; Tang, M

    2006-05-17

    We outline a method to study the spatial and orientation statistics of dynamical dislocation systems by modeling the dislocations as a stochastic fiber process. Statistical measures have been introduced for the density, velocity, and flux of dislocations, and the connection between these measures and the dislocation state and plastic distortion rate in the crystal is explained. A dislocation dynamics simulation model has been used to extract numerical data to study the evolution of these statistical measures numerically in a body-centered cubic crystal under deformation. The orientation distribution of the dislocation density, velocity and dislocation flux, as well as the dislocation correlations have been computed. The importance of the statistical measures introduced here in building continuum models of dislocation systems is highlighted.

  14. The clinical effect of reposition by manual reduction at different postures in 70 patients with anterior dislocation of shoulder joint%不同体位手牵足蹬法治疗肩关节前脱位70例临床疗效

    姚丽; 应盛国

    2015-01-01

    Objective: To observe the clinical effect of reposition by manual reduction at different postures in patients with the primary anterior dislocation of shoulder joint.Methods:Seventy patients with the primary anterior dislocation of shoulder joint were collected and divided into a prone position group with 35 cases and a supine position one with 35 ones according to the different postures. The treatment effects of two groups were evaluated with the reference of the standard of shoulder joint reposition.Results: The reposition rate without anesthetic and total reposition rate were 71.43% (25/35) and 94.29% (33/35) in the prone position group and 62.86% (22/35) and 80.00% (28/35) in the supine group. The difference between two groups had the statistical signiifcance (P<0.05).Conclusion: In the treatment of anterior dislocation of shoulder joint, the effect of Hippocrates (manual reduction) is obviously better in the prone posture than in the supine posture.%目的:观察不同体位手牵足蹬法治疗原发性肩关节前脱位的临床疗效.方法:收集原发性肩关节前脱位患者70例,根据不同体位分为俯卧位手牵足蹬法复位治疗(俯卧位组)35例和仰卧位手牵足蹬法复位治疗(仰卧位组) 35例.参照肩关节复位标准评价两组疗效.结果:观察组无麻药复位率为71.43%(25/35),总复位率为94.29%(33/35);对照组无麻药复位率为62.86%(22/35),总复位率为80.00%(28/35),组间差异有统计学意义(P<0.05).结论:俯卧位手牵足蹬法治疗肩关节前脱位疗效优于仰卧位手牵足蹬法.

  15. First-time anterior shoulder dislocations: should they be arthroscopically stabilised?

    Sedeek, Sedeek Mohamed; Bin Abd Razak, Hamid Rahmatullah; Ee, Gerard WW; Tan, Andrew HC

    2014-01-01

    The glenohumeral joint is inherently unstable because the large humeral head articulates with the small shadow glenoid fossa. Traumatic anterior dislocation of the shoulder is a relatively common athletic injury, and the high frequency of recurrent instability in young athletes after shoulder dislocation is discouraging to both the patient and the treating physician. Management of primary traumatic shoulder dislocation remains controversial. Traditionally, treatment involves initial immobilis...

  16. Comparison of four different reduction methods for anterior dislocation of the shoulder

    Guler, Olcay; Ekinci, Safak; Akyildiz, Faruk; Tirmik, Uzeyir; Cakmak, Selami; Ugras, Akin; Piskin, Ahmet; Mahirogullari, Mahir

    2015-01-01

    Background Shoulder dislocations account for almost 50 % of all major joint dislocations and are mainly anterior. Objective The aim is a comparative retrospective study of different reduction maneuvers without anesthesia to reduce the dislocated shoulder. Methods Patients were treated with different reduction maneuvers, including various forms of traction and external rotation, in the emergency departments of four training hospitals between 2009 and 2012. Each of the four hospitals had differ...

  17. Dislocation Dynamics During Plastic Deformation

    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.

  18. To Observe the Clinical Effect of Stimson Reduction Method Cooperate with Zhuang Medicated Thread Moxibustion in Treating Adults with Acute Anterior Dislocation of Shoulder Joint%Stimson复位法配合壮医药线点灸治疗青壮年肩关节前脱位疗效观察

    于小中; 洪定钢; 王效柱

    2013-01-01

    Objective:To observe the clinical effect of Stimson reduction method cooperate with Zhuang medicated thread moxibus-tion in treating adults with acute anterior dislocation of shoulder joint. Methods:36 cases of patients with Stimson reduction method are reset, and cooperate with Zhuang medicated thread moxibustion therapy in the treatment of intraoperative and postoperative. Re-sults:36 patients were all one-time success, with no use of anesthesia, patients were followed up for 6 months, the shoulder joint function of the patients recovered well, the total efficiency was 100%. Conclusion:Using Stimson reduction method cooperate with Zhuang medicated thread moxibustion in treating adults with acute anterior dislocation of shoulder joint is simple and effective, avoiding the use of anesthesia, and worth further clinical application.%  目的:观察Stimson复位法配合壮医药线点灸治疗青壮年急性肩关节前脱位的临床疗效。方法:对36例青壮年急性肩关节前脱位采用Stimson复位法进行复位,并在术中及术后配合患肩壮医药线点灸治疗。结果:36例患者全部一次性复位成功,无一例使用麻醉,随访半年,患者肩关节功能均恢复良好,总有效率100%。结论:采用Stimson复位法配合壮医药线点灸治疗青壮年急性肩关节前脱位操作方法简单,疗效肯定,避免了使用麻醉,值得临床进一步推广应用。

  19. Dislocation-dislocation and dislocation-twin reactions in nanocrystalline Al by molecular-dynamics simulation.

    Yamakov, V.; Wolf, D.; Phillpot, S. R.; Gleiter, H.; Materials Science Division; Forschungszentrum Karlsruhe

    2003-08-15

    We use massively parallel molecular dynamics simulations of polycrystal plasticity to elucidate the intricate dislocation dynamics that evolves during the process of deformation of columnar nanocrystalline Al microstructures of grain size between 30 and 100 nm. We analyze in detail the mechanisms of dislocation-dislocation and dislocation-twin boundary reactions that take place under sufficiently high stress. These reactions are shown to lead to the formation of complex twin networks, i.e. structures of coherent twin boundaries connected by stair-rod dislocations. Consistent with recent experimental observations, these twin networks may cause dislocation pile-ups and thus give rise to strain hardening.

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

    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.

  1. Supersonic Dislocation Bursts in Silicon

    Hahn, E. N.; Zhao, S.; Bringa, E. M.; Meyers, M. A.

    2016-06-01

    Dislocations are the primary agents of permanent deformation in crystalline solids. Since the theoretical prediction of supersonic dislocations over half a century ago, there is a dearth of experimental evidence supporting their existence. Here we use non-equilibrium molecular dynamics simulations of shocked silicon to reveal transient supersonic partial dislocation motion at approximately 15 km/s, faster than any previous in-silico observation. Homogeneous dislocation nucleation occurs near the shock front and supersonic dislocation motion lasts just fractions of picoseconds before the dislocations catch the shock front and decelerate back to the elastic wave speed. Applying a modified analytical equation for dislocation evolution we successfully predict a dislocation density of 1.5 × 1012 cm‑2 within the shocked volume, in agreement with the present simulations and realistic in regards to prior and on-going recovery experiments in silicon.

  2. [Spasm of the adductor muscles, pre-dislocations and dislocations of the hip joints in children and adolescents with cerebral palsy. Clinical observations on aetiology, pathogenesis, therapy and rehabilitation. Part II. The importance of the iliopsoas tendon, its tenotomy, of the coxa valga antetorta, and correction through osteotomy turning the hip into varus (author's transl)].

    Fettweis, E

    1979-02-01

    The following factors besides spasm and contraction of the adductor muscles contribute to the occurrence of dislocations of the hip in spastic paralysis: Spasm and contraction of the iliopsoas muscle and enhanced valgus position and antetorsion. The author holds the opinion that in case of malformation of the proximal end of the femur, it is not only the indirect action of the spastic musculature via the proximal femur-epiphyseal cartilage which is responsible for this phenomen in accordance with the law on functional adaption through longitudinal growth (Pauwels), but also the direct traction of the iliopsoas tendon. A clue in this direction is the often very pronounced elongation or enlargement of the trochanter minor. The author demonstrates the pathogenetic importance of iliopsoas contracture and malpositioning of the neck of the femur by means of analyses of the course in two patients. The following principles of treatment are postulated for spastic dislocation of the hip: Elimination of the pathogenetic factors through myotenotomy of the adductor muscles and complete resection of the obturator nerve, with observation of strict aftertreatment criteria, tenotomy of the iliopsoas, repositioning and osteotomy with turning into varus. Osteotomy without previous elimination of the pathogenetically acting muscular forces does not appear useful. Likewise, permanent re-positioning by means of muscle-relaxing operation cannot be sufficiently safe-guarded without additional osteotomy once the dislocation has taken place. In twelve patients with spastic dislocation of the hip, treated in accordance with these guidelines (two without osteotomy) aged 6 6/12 and 19 5/12 years, a roentgenologically good result was obtained in half of the cases, whereas the functional result was satisfactory not only with these patients but also with part of the other patients. If surgical treatment is instituted early enough, and if the experiences described here are taken into consideration

  3. 解剖钢板治疗65例肩关节脱位合并肱骨大结节骨折效果分析%The effect analysis on anatomic plate for 65 cases with shoulder joint dislocation and humeral grea-ter tubercle fracture

    夏卫民

    2016-01-01

    Objective:To analyze and explore the clinical effect of anatomic plate for shoulder joint dislocation with hu-meral greater tubercle fracture. Methods:Sixty - five cases with shoulder joint dislocation and humeral greater tubercle fracture were selected and treatment by anatomic plate. For 3 ~ 4 weeks of rehabilitation,and a 6 - month follow - up for all patients. To evaluate and analyze the clinical treatment effect. Results:Plan and dysfunction is meliorative,range of motion,anatomical re-duction return to normal. 45 cases in 65 cases of patient are better,11 patients are good,the total rate is 86. 15% . Conclusion:The effect of anatomic plate for shoulder joint dislocation and humeral greater tubercle fracture was significant.%目的:分析和探讨解剖钢板治疗肩关节脱位合并肱骨大结节骨折的临床治疗效果。方法:应用解剖钢板治疗65例肩关节脱位合并肱骨大结节骨折患者。术后进行为期3~4周的康复训练,随访6个月。评价分析临床治疗效果。结果:解剖钢板治疗法临床疗效显著,疼痛、功能障碍、肩关节活动范围、解剖复位均恢复正常。65例患者中,优45例,良11例,总优良率为86.15%。结论:解剖钢板治疗肩关节脱位合并肱骨大结节骨折的临床治疗效果显著,具有一定的临床实用价值。

  4. Finite strain discrete dislocation plasticity

    Deshpande, VS; Needleman, A; Van der Giessen, E

    2003-01-01

    A framework for carrying out finite deformation discrete dislocation plasticity calculations is presented. The discrete dislocations are presumed to be adequately represented by the singular linear elastic fields so that the large deformations near dislocation cores are not modeled. The finite defor

  5. Behavior of dislocations in silicon

    Sumino, Koji [Nippon Steel Corp., Chiba Prefecture (Japan)

    1995-08-01

    A review is given of dynamic behavior of dislocations in silicon on the basis of works of the author`s group. Topics taken up are generation, motion and multiplication of dislocations as affected by oxygen impurities and immobilization of dislocations due to impurity reaction.

  6. Phonon-dislocation interaction

    Thermal conductivity measurements on LiF crystals in the temperature range 0.04 to 30 K have demonstrated that, throughout this range, thermal phonons interact with dislocations via a dynamic or resonant process which is highly frequency- and phonon-mode dependent. The results of earlier work are consistent with this interpretation

  7. 先天性髋关节脱位术后康复训练38例体会%Experience of postoperative rehabilitation training on 38 cases of congenital dislocation of hip joint

    闫庆荣; 丁新友

    2003-01-01

    @@ BACKGROUND: Postoperative long-tern immobilization ofdislocation of hip joint may lead to degradation of ligament structure, decreasing of intensity and decline of stress ability. Besides tissue proliferation, organization and adhesion in the course of repairing will lead to dysfunction of hip jolt even stiffness. So planned rehabilitation training on hip joint is very necessary.

  8. Clinical outcomes of the combined lumb-saero-iliac fixation in treatment of sacroiliac joint fractures and dislocation%腰骶髂联合固定治疗骶髂关节骨折脱位的疗效分析

    郭新钾; 孙兆云; 李雪芹; 董长军

    2011-01-01

    Objective To evaluate the clinical outcomes of the combined lumb-sacio-iliac fixation in treatment of sacroiliac joint fractures and dislocation. Methods From Jul 2007 to Jan 2010,11 patients(6 males and S females) with sacroiliac joint fractures and dislocation were treated with operation combined lumb-sacro-iliac fixation. According to the classification of Tile, 11 patients were classified as type C . This fixation combined a posterior pedicle screw system which fixed L5 / S1 with a ilium screw which fixed the posterior iliac spine after replacement by drafting affected leg and bracing or rejoining the screw. Results All 11 patients were followed up 12~20 months after surgery, with an average of 16.5 months. Postoperative X-ray showed satisfactory reduction of sacroiliac joint fractures and dislocation. No iatrogenic complications of neurovascular injury occurred. Patients now walk unassistedly without pain in the waist or legs, and with no shortening of lower limbs or claudication. By considering symptom and satisfactory scores, the Majeed functional assessment revealed that patients had 9 excellent and 2 good at 12 months after surgery. Conclusion The combined lumb-sacro-iliac fixation allowed early mobilization and ambulation, with general applicability and definite safety,is an effective surgical technique for the treatment of sacroiliac joint fractures and dislocation.%目的 探讨应用腰骶髂联合固定治疗骶髂关节骨折脱位的临床效果.方法 对2007年7月~2010年1月收治的11例骶髂关节骨折脱位的骨盆骨折患者进行手术治疗.男6例,女5例;年龄21~60岁,平均36岁.11例均为Tile C型骨盆骨折.采用后路腰骶髂切口,椎弓根钉棒系统固定L5/S1椎体和髂骨螺钉固定髂骨,配合患肢牵引和器械的撑开、合拢纠正垂直及分离移位.结果 11例患者术后获得12~20个月随访,平均16.5个月.术后X线片均示骶髂关节骨折脱位复位固定满意,骨盆后环形态恢

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

    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.

  10. Humeral shaft fracture with ipsilateral shoulder dislocation

    Behera Prateek

    2014-02-01

    Full Text Available 【Abstract】Although fracture of the humeral shaft or dislocation of the shoulder joint is a common injury, a simutaneous injury is rare. We present such a case combined with head injury which took precedence over the skeletal injuries. The postoperative rehabilitation was slowed down by the head injury. This case report makes us aware of some problems when managing the patient with this rare injury and helps us understand the management options better. Also the need for proper follow-up and rehabilitation is emphasized.

  11. Humeral shaft fracture with ipsilateral shoulder dislocation

    Prateek Behera; Vishal Kumar; Sameer Aggarwal

    2014-01-01

    Although fracture of the humeral shaft or dislocation of the shoulder joint is a common injury,a simutaneous injury is rare.We present such a case combined with head injury which took precedence over the skeletal injuries.The postoperative rehabilitation was slowed down by the head injury.This case report makes us aware of some problems when managing the patient with this rare injury and helps us understand the management options better.Also the need for proper follow-up and rehabilitation is emphasized.

  12. Fractures and Dislocations About the Elbow and Their Adverse Sequelae: Contemporary Perspectives.

    Horrigan, Patrick; Braman, Jonathan P; Harrison, Alicia

    2016-01-01

    Fractures and dislocations of the elbow can result in adverse outcomes. The elbow is a unique joint that allows for great mobility but is predisposed to instability, either simple or complex, in traumatic settings. Even simple elbow instability, in which no fracture is present, may be associated with tremendous soft-tissue injury. Surgical treatment is often required for complex instability in which various fractures are present. The treatment goals for fixation of elbow fractures and dislocations include stable fracture fixation, a stable concentrically reduced joint, and early range of motion. Continued pain, stiffness, and instability as well as heterotopic ossification are common sequelae of elbow fractures and dislocations. PMID:27049181

  13. Multiple spontaneous dislocations in a patient with Ehlers-Danlos syndrome.

    Dabbas, N; Saker, R; Blakeley, C

    2008-03-01

    Ehlers-Danlos syndrome (EDS) consists of a heterogeneous group of inherited connective tissue disorders, characterised by generalised joint hypermobility, hyperextensibility of the skin, dystrophic scars, and a tendency to excessive bleeding. Sequelae include recurrent low impact trauma dislocations, chronic joint pain, and early osteoarthritis. This report describes a case of multiple simultaneous dislocations at distant sites. We highlight the importance of paying consideration to the exposure of patients to large cumulative doses of ionising radiation to diagnose and confirm reduction of frequent dislocations, and ask whether radiographic confirmation is necessary on every occasion in this subset of patients. PMID:18299375

  14. Interaction of dislocation loops with dislocations studied by dislocation dynamics in α-iron

    Shi, X. J.; Dupuy, L.; Devincre, B.; Terentyev, D.; Vincent, L.

    2015-05-01

    Interstitial dislocation loops with Burgers vector of 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.

  15. Motor evoked potentials and spontaneous electromyography in reconstruction of pelvic fracture combined with sacroiliac joint dislocation%骨盆骨折合并骶髂关节脱位术中电生理监测技术的应用

    陈艺; 林志雄; 黎文; 刘琦; 严广斌; 张姝江; 余楠生

    2013-01-01

    目的 探讨骨盆骨折合并骶髂关节脱位手术中应用电生理监测技术预防神经损伤的效果.方法 对需要手术治疗的骨盆骨折合并骶髂关节脱位患者,术中对术侧采用经颅电刺激运动诱发电位(TES-MEP)和自由肌电图(EMG)进行实时监测,观察其对坐骨神经和腰5神经根医源性损伤的预防效果.结果 骶髂关节复位固定时,术侧股二头肌、胫前肌、胫后肌MEP波幅下降,但波形均能引出.耻骨复位时,MEP波形稳定.因手术操作引发趾短伸肌、胫后肌短暂、高幅EMG反应,即刻提醒术者,避免频繁,粗暴骚扰神经组织.术后骶髂关节、耻骨复位良好,且未出现医源性神经损伤.结论 联合运用MEP和自由EMG实时监测能及时反映骨盆骨折合并骶髂关节脱位切开复位内固定术中坐骨神经及L5神经根受激惹情况和运动功能状态,提高手术精确性,值得在临床推广应用.%Objective To investigate the efficacy of nerve damage prevention using electrophysiological monitoring techniques during reconstruction of pelvic fracture combined with sacroiliac joint dislocation. Methods Intraoperative real-time monitoring by motor evoked potentials with trans-cranial electrical stimulation (TES-MEP) and spontaneous electromyogram (EMG) were performed during surgical treatment for the patient of pelvic fracture combined with sacroiliac joint dislocation. The preventive effects on iatrogenic injury of sciatic nerve and L5 nerve root were observed. Results The TES-MEP volatility of biceps femoris, tibialis anterior muscle and posterior tibial muscle dropped on the surgical side when resetting sacroiliac joint, but the waveform could be elicited. The TES-MEP waveform was stable when resetting pubis. Some short, high-amplitude EMG response appeared in extensor digitorum brevis and posterior tibial muscle due to surgical operation, so that the surgeons could be immediately aware of avoiding irritation for nerve tissues

  16. Bilateral inferior dislocation of the hip-a case report

    Bhagwat Kishan R

    2012-04-01

    Full Text Available 【Abstract】Inferior dislocation of the hip is the ra-rest type in hip dislocation. Very few cases have been re-ported in the anglophonic literature, most of which involved the pediatric age group. Surprisingly, we came across a 30-year-old patient with a bilateral inferior hip dislocation. He had sustained a road traffic accident and the attitude of both hip joints was flexion and abduction. The diagnosis was confirmed by radiographs which revealed the long axis of the femur at an angle of 110 (right degrees and 100 (left degrees respectively away from the axis. Closed reduction under sedation was successfully performed. Skin traction for a period of 6 weeks was advised and the follow-up re-vealed an excellent result. We present the details of this case, the first of its kind along with a review of the literature, discussing the various modes and mechanisms of injury inducing inferior dislocation of the hip. Key words: Hip dislocation; Joints; Femur

  17. 肩关节前、后路手术治疗产瘫肩关节内旋挛缩伴盂肱关节后脱位%Surgical treatment of shoulder joint posterior dislocation secondary to internal rotation contractnre deformity in brachial plexus birth palsy

    王树锋; 栗鹏程; 薛云皓; 李玉成; 孙燕琨

    2012-01-01

    目的 观察肩关节前路松解复位、后路关节囊紧缩治疗产瘫肩关节内旋挛缩畸形伴肩关节后脱位的临床效果. 方法 19例产瘫并发肩关节内旋挛缩畸形患者,经X线和CT检查确诊为盂肱关节半脱位伴假盂形成或完全脱位.男14例,女5例,年龄2.5 ~ 8.5岁,平均5岁.盂肱关节畸形按照改良的Water的标准进行分型,Ⅳ型15例,Ⅴ型4例.19例均行肩关节前路挛缩软组织松解、复位,同时行后路剥离关节囊与假盂的粘连并紧缩后下方关节囊,肩关节外旋0°位石膏固定4周. 结果 术后随访12 ~ 36个月,平均20个月.肩关节Mallet评分由术前平均(11.4±1.7)(7~16)分至术后(15.5±1.8)(13~19)分,两者差异有统计学意义(P<0.05);术后盂肱关节达到中心性复位的有16例;3例肱骨头仍向后脱位. 结论 对于产瘫肩关节内旋挛缩导致的肩关节脱位,前路松解复位、后路剥离关节囊与假盂粘连、紧缩后下侧关节囊,不但使脱位的盂肱关节达到中心复位,同时明显改善其肩关节的功能.%Objective To observe the functional recovery of shoulder joint and the reduction of posterior dislocated humeral head in children with shoulder joint internal rotation contracture and humeral head posterior dislocation secondary to brachial plexus birth palsy treated by a modified surgical procedure through the anterior combined posterior approach of the shoulder. Methods Ninteen patients,ranging in age from 2.5 to 8.5 years (average 5 years),suffered posterior dislocation of the shoulder joint secondary to internal rotation contracture in brachial plexus birth palsy. The gleno-humeral joint deformity was confirmed by X-ray and CT examination and classified as type Ⅳ in 15 eases and typeⅤin 4 cases according to the modified water's criteria.The surgical procedure was as follows:the contracture soft tissue around the anterior of shoulder joint was released firstly through the anterior approach

  18. Thermodynamically consistent continuum dislocation dynamics

    Hochrainer, Thomas

    2016-03-01

    Dislocation based modeling of plasticity is one of the central challenges at the crossover of materials science and continuum mechanics. Developing a continuum theory of dislocations requires the solution of two long standing problems: (i) to represent dislocation kinematics in terms of a reasonable number of variables and (ii) to derive averaged descriptions of the dislocation dynamics (i.e. material laws) in terms of these variables. The kinematic problem (i) was recently solved through the introduction of continuum dislocation dynamics (CDD), which provides kinematically consistent evolution equations of dislocation alignment tensors, presuming a given average dislocation velocity (Hochrainer, T., 2015, Multipole expansion of continuum dislocations dynamics in terms of alignment tensors. Philos. Mag. 95 (12), 1321-1367). In the current paper we demonstrate how a free energy formulation may be used to solve the dynamic closure problem (ii) in CDD. We do so exemplarily for the lowest order CDD variant for curved dislocations in a single slip situation. In this case, a thermodynamically consistent average dislocation velocity is found to comprise five mesoscopic shear stress contributions. For a postulated free energy expression we identify among these stress contributions a back-stress term and a line-tension term, both of which have already been postulated for CDD. A new stress contribution occurs which is missing in earlier CDD models including the statistical continuum theory of straight parallel edge dislocations (Groma, I., Csikor, F.F., Zaiser, M., 2003. Spatial correlations and higher-order gradient terms in a continuum description of dislocation dynamics. Acta Mater. 51, 1271-1281). Furthermore, two entirely new stress contributions arise from the curvature of dislocations.

  19. Shoulder dislocation in patients older than 60 years of age

    Rapariz Jose

    2010-01-01

    Full Text Available Purpose: Recurrent anterior shoulder dislocation in elderly patients is a little studied condition. The goal of this paper is to clarify the role of associated injuries with respect to loss of function and recurrence of dislocation. Materials and Methods: We have conducted a retrospective, descriptive study on 29 patients older than 60 years at the moment they suffered their first dislocation episode. All patients were assessed clinically (Constant test and by imaging testing (X-ray, MRI. Results: Nine (31.03% out of 29 patients had a recurrent dislocation. Four of them required reconstructive surgery to maintain joint stability. Injury to the anterior support (anterior labrum, anterior glenoid rim showed a statistically significant relation to the recurrence of dislocations. The occurrence or non-occurrence of a rotator cuff tear does have an impact on the shoulder function. The degree of rotator cuff involvement on the coronal plane does not significantly affect the shoulder′s functional outcome. The tear extension on the sagittal plane does cause impairment on the Constant test. Conclusions: Labrum and/or anterior glenoid involvement should be suspected in elderly patients presenting with recurrent shoulder dislocation. Recurrence is due to an injury in the anterior support or both (anterior and posterior, even though shoulder function gets impaired when a rotation cuff tear occurs with anterior extension on the sagittal plane. Evidence level: IV Case series.

  20. CT findings of traumatic posterior hip dislocation after reduction

    Moon, Sung Kyoung; Park, Ji Seon; Ryu, Kyung Nam; Jin, Wook [Kyung Hee University Medical Center, Seoul (Korea, Republic of); Jin Wook

    2008-06-15

    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.

  1. Imaging of traumatic dislocation of the hip in childhood

    Vialle, Raphael; Pannier, Stephanie; Odent, Thierry; Glorion, Christophe [Necker Enfants-Malades Hospital, Department of Paediatric Orthopaedics, Paris Cedex 15 (France); Schmit, Pierre [Necker Enfants-Malades Hospital, Department of Paediatric Radiology, Paris (France); Pauthier, Francois [CHI Poissy Saint Germain en Laye, Department of Orthopaedic Surgery, Poissy (France)

    2004-12-01

    Traumatic hip dislocation in childhood is a rare consequence of violent trauma. After reduction, outcome is usually favourable although epiphyseal necrosis can occur. Reduction must be carried out as soon as possible and is achieved easily, although if the labrum is involved, surgery may be required to achieve complete reduction. To analyze a retrospective series of traumatic hip dislocations in children, describing the therapeutic and imaging strategy. A total of 42 patients were studied. Their mean age was 10 years 3 months. All relevant radiographic, CT, MRI and radionuclide bone scan examinations were reviewed. Special attention was paid to associated lesions. In 22 patients the dislocation was caused by low-energy trauma. Road traffic accidents accounted for 17 dislocations. An acetabular fracture was present in six patients and the femoral head was fractured in three. Reduction was easily achieved in 31 patients. In 11 patients the postreduction radiograph and CT showed joint space asymmetry secondary to labral entrapment. Only two patients developed epiphyseal necrosis. It has been difficult to define and evaluate accurate principles for a medical imaging strategy in this group of patients. Analysis of plain radiographs is essential before and after reduction of the joint, and it is important to perform postreduction CT in every patient whose joint space remains widened. A radionuclide bone scan should be performed between the second and third weeks after injury to assess epiphyseal vascularity. With the use of specific sequences, MRI may be an alternative modality to assess epiphyseal vitality. (orig.)

  2. Imaging of traumatic dislocation of the hip in childhood

    Traumatic hip dislocation in childhood is a rare consequence of violent trauma. After reduction, outcome is usually favourable although epiphyseal necrosis can occur. Reduction must be carried out as soon as possible and is achieved easily, although if the labrum is involved, surgery may be required to achieve complete reduction. To analyze a retrospective series of traumatic hip dislocations in children, describing the therapeutic and imaging strategy. A total of 42 patients were studied. Their mean age was 10 years 3 months. All relevant radiographic, CT, MRI and radionuclide bone scan examinations were reviewed. Special attention was paid to associated lesions. In 22 patients the dislocation was caused by low-energy trauma. Road traffic accidents accounted for 17 dislocations. An acetabular fracture was present in six patients and the femoral head was fractured in three. Reduction was easily achieved in 31 patients. In 11 patients the postreduction radiograph and CT showed joint space asymmetry secondary to labral entrapment. Only two patients developed epiphyseal necrosis. It has been difficult to define and evaluate accurate principles for a medical imaging strategy in this group of patients. Analysis of plain radiographs is essential before and after reduction of the joint, and it is important to perform postreduction CT in every patient whose joint space remains widened. A radionuclide bone scan should be performed between the second and third weeks after injury to assess epiphyseal vascularity. With the use of specific sequences, MRI may be an alternative modality to assess epiphyseal vitality. (orig.)

  3. Les dislocations: textes et contextes

    Leonarduzzi, Laetitia; Herry, Nadine

    2005-01-01

    In this paper we analyse the contexts in which left and right dislocations appear. Our corpus is based on written as well as oral discourse, with texts ranging from the year 1884 to 2005. After trying to define both types of dislocation, and seeing how far the definitions can be extended, we notice that the dislocated NP is most of the time definite (90% of our examples). This phenomenon may be explained by the notions of anaphora, deixis and thematisation. Dislocations appear both in oral an...

  4. Design rules for dislocation filters

    The efficacy of strained layer threading dislocation filter structures in single crystal epitaxial layers is evaluated using numerical modeling for (001) face-centred cubic materials, such as GaAs or Si1−xGex, and (0001) hexagonal materials such as GaN. We find that threading dislocation densities decay exponentially as a function of the strain relieved, irrespective of the fraction of threading dislocations that are mobile. Reactions between threading dislocations tend to produce a population that is a balanced mixture of mobile and sessile in (001) cubic materials. In contrast, mobile threading dislocations tend to be lost very rapidly in (0001) GaN, often with little or no reduction in the immobile dislocation density. The capture radius for threading dislocation interactions is estimated to be approximately 40 nm using cross section transmission electron microscopy of dislocation filtering structures in GaAs monolithically grown on Si. We find that the minimum threading dislocation density that can be obtained in any given structure is likely to be limited by kinetic effects to approximately 104–105 cm−2

  5. Design rules for dislocation filters

    Ward, T.; Sánchez, A. M.; Beanland, R., E-mail: r.beanland@warwick.ac.uk [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom); Tang, M.; Wu, J.; Liu, H. [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Dunstan, D. J. [School of Physics and Astronomy, Queen Mary University of London, London E1 4NS (United Kingdom)

    2014-08-14

    The efficacy of strained layer threading dislocation filter structures in single crystal epitaxial layers is evaluated using numerical modeling for (001) face-centred cubic materials, such as GaAs or Si{sub 1−x}Ge{sub x}, and (0001) hexagonal materials such as GaN. We find that threading dislocation densities decay exponentially as a function of the strain relieved, irrespective of the fraction of threading dislocations that are mobile. Reactions between threading dislocations tend to produce a population that is a balanced mixture of mobile and sessile in (001) cubic materials. In contrast, mobile threading dislocations tend to be lost very rapidly in (0001) GaN, often with little or no reduction in the immobile dislocation density. The capture radius for threading dislocation interactions is estimated to be approximately 40 nm using cross section transmission electron microscopy of dislocation filtering structures in GaAs monolithically grown on Si. We find that the minimum threading dislocation density that can be obtained in any given structure is likely to be limited by kinetic effects to approximately 10{sup 4}–10{sup 5 }cm{sup −2}.

  6. Dislocation dynamics in nanocrystalline nickel.

    Shan, Z W; Wiezorek, J M K; Stach, E A; Follstaedt, D M; Knapp, J A; Mao, S X

    2007-03-01

    It is believed that the dynamics of dislocation processes during the deformation of nanocrystalline materials can only be visualized by computational simulations. Here we demonstrate that observations of dislocation processes during the deformation of nanocrystalline Ni with grain sizes as small as 10 nm can be achieved by using a combination of in situ tensile straining and high-resolution transmission electron microscopy. Trapped unit lattice dislocations are observed in strained grains as small as 5 nm, but subsequent relaxation leads to dislocation recombination. PMID:17359167

  7. Annealing of dislocation loops in dislocation dynamics simulations

    We report of 3-dimensional discrete dislocation dynamics (DDD) simulations of dislocation loops coarsening by vacancy bulk diffusion. The calculation is based upon a model which couples the diffusion theory of vacancies to the DDD in order to obtain the climb rate of the dislocation segments. Calculation of isolated loops agrees with experimental observations, i.e. loops shrink or expand, depending on their type and vacancy supersaturation. When an array of dislocation loops of various sizes is considered, and the total number of vacancies in the simulation is maintained constant, the largest dislocations are found to increase in size at the expense of small ones, which disappear in a process known as Ostwald ripening.

  8. Annealing of dislocation loops in dislocation dynamics simulations

    Mordehai, Dan; Clouet, Emmanuel [SRMP, CEA-Saclay, 91191 Gif-sur-Yvette Cedex (France); Fivel, Marc; Verdier, Marc, E-mail: danmord@tx.technion.ac.il [CNRS/SIMAP, INPG, BP 75, 38402 St Martin d' Heres (France)

    2009-07-15

    We report of 3-dimensional discrete dislocation dynamics (DDD) simulations of dislocation loops coarsening by vacancy bulk diffusion. The calculation is based upon a model which couples the diffusion theory of vacancies to the DDD in order to obtain the climb rate of the dislocation segments. Calculation of isolated loops agrees with experimental observations, i.e. loops shrink or expand, depending on their type and vacancy supersaturation. When an array of dislocation loops of various sizes is considered, and the total number of vacancies in the simulation is maintained constant, the largest dislocations are found to increase in size at the expense of small ones, which disappear in a process known as Ostwald ripening.

  9. Biomechanical loading of the shoulder complex and lumbosacral joints during dynamic cart pushing task.

    Nimbarte, Ashish D; Sun, Yun; Jaridi, Majid; Hsiao, Hongwei

    2013-09-01

    The primary objective of this study was to quantify the effect of dynamic cart pushing exertions on the biomechanical loading of shoulder and low back. Ten participants performed cart pushing tasks on flat (0°), 5°, and 10° ramped walkways at 20 kg, 30 kg, and 40 kg weight conditions. An optoelectronic motion capturing system configured with two force plates was used for the kinematic and ground reaction force data collection. The experimental data was modeled using AnyBody modeling system to compute three-dimensional peak reaction forces at the shoulder complex (sternoclavicular, acromioclavicular, and glenohumeral) and low back (lumbosacral) joints. The main effect of walkway gradient and cart weight, and gradient by weight interaction on the biomechanical loading of shoulder complex and low back joints was statistically significant (all p distraction loading of glenohumeral joint and inferosuperior loading of the acromioclavicular joint may contribute to the risk of work-related low back and shoulder musculoskeletal disorder with prolonged and repetitive use of carts. PMID:23566675

  10. Treatment of patients with acromioclavicular joint injuries (Rockwood II-VI) with modeled Kirschner wire and cortical screw

    Ivan Viktorovich Borozda; Mikhail Anatolievich Danilov; Kirill Sergeevich Golokhvast

    2015-01-01

    Objective:To propose an original method of surgical treatment for the acromial extremity of the clavicle rupture (Rockwood II-VI) with modeled Kirschner wire and cortical screw. Methods:Anatomical study and a test method were applied to 43 cadavers of both sexes. During the period between 2000 and 2013, 34 patients of both sexes were operated upon using the new method. In the comparison group (n=120), the fixation of the acromial extremity of the clavicle rupture was performed with hamate plate, Lee hook and Kirschner wires. Results:Its application allows, according to the evaluation scale of Constant and Murley (1987), 10%more preservation of the function of the shoulder compared with traditional methods of surgical treatment, and shortens the required hospital treatment and temporary disability periods. Conclusions: It is shown that the proposed author’s method combines low invasiveness, minimum dimensions of the construction and low-cost treatment.

  11. Treatment of patients with acromioclavicular joint injuries(Rockwood II-VI) with modeled Kirschner wire and cortical screw

    Ivan; Viktorovich; Borozda; Mikhail; Anatolievich; Danilov; Kirill; Sergeevich; Golokhvast

    2015-01-01

    Objective: To propose an original method of surgical treatment for the acromial extremity of the clavicle rupture(Rockwood II-VI) with modeled Kirschner wire and cortical screw. Methods: Anatomical study and a test method were applied to 43 cadavers of both sexes. During the period between 2000 and 2013, 34 patients of both sexes were operated upon using the new method. In the comparison group(n = 120), the fixation of the acromial extremity of the clavicle rupture was performed with hamate plate, Lee hook and Kirschner wires.Results: Its application allows, according to the evaluation scale of Constant and Murley(1987), 10% more preservation of the function of the shoulder compared with traditional methods of surgical treatment, and shortens the required hospital treatment and temporary disability periods.Conclusions: It is shown that the proposed author’s method combines low invasiveness, minimum dimensions of the construction and low-cost treatment.

  12. Traumatic hip dislocations in children

    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

  13. Nature of Dislocations in Silicon

    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...

  14. CT diagnosis in the elbow joint

    The normal anatomy of the elbow joint is described. Diverse pathologic joint alterations, e.g. fractures and dislocations, ostheochondritis, inflammatory changes, and ulnar nerve lesion are demonstrated. Particular attention is paid to threedimensional (3D-) reconstruction of demonstrable pathologic findings. (orig.)

  15. Subtalar dislocation: management and prognosis for an uncommon orthopaedic condition.

    Prada-Cañizares, Alfonso; Auñón-Martín, Ismael; Vilá Y Rico, Jesús; Pretell-Mazzini, Juan

    2016-05-01

    Subtalar dislocations were first described in 1811 as the simultaneous dislocation of the talo-calcaneal and talo-navicular joints without any tibio-talar or talar neck associated fractures. They were classified in 1853 as: medial, lateral, posterior and anterior based on the displacement of the foot in relationship to the talus. These are uncommon injuries, representing approximately 1 % of all traumatic injuries of the foot and 1-2 % of all dislocations, being associated with high energy trauma.Closed reduction of these dislocations should be performed as early as possible to avoid further damage to the skin and neurovascular structures. If this is not possible, then open reduction without further delay is recommended. Irreducible injuries have been reported in 0 to 47 % of cases. Open dislocations represent between 46 and 83 % of all cases, and have been associated with poor prognosis. Associated fractures have a high incidence, the most frequent ones are the posterior process of the talus, talar head, external malleolus, medial malleolus and the tubercle of the fifth metatarsal.These types of injuries are not faced by orthopaedic surgeons on a daily basis and having a source of information on how to manage and what to expect is important. We present an up-to-date literature review on the epidemiology, clinical presentation, radiologic assessment, treatment options and prognostic factors of these uncommon injuries. PMID:26208589

  16. 120 Cases of Shoulder Dislocation referred to Emergency Department during One Year; a Case Series Study

    Payman Asadi

    2015-05-01

    Full Text Available Shoulder dislocation is identified as displacement of humerus head from the glenoid cavity of scapula bone, which makes up about 50% of total joint dislocations. Taking into account the importance of the side effects and disabilities caused by this type of dislocation and that it can be prevented, the present study was designed aiming to evaluate the epidemiologic characteristics of the patients with shoulder dislocation. In this retrospective cross-sectional study, all the patients referred to the emergency department (ED with complaint of shoulder dislocation throughout one year were evaluated. Demographic data and characteristics regarding the type of dislocation, presence of accompanying fractures, mechanism of dislocation, history of dislocation and the method of reduction were extracted from the patients’ profiles and recorded in a checklist designed for this purpose. Data were then statistically analyzed using SPSS version 19. Statistics showed that 120 patients with the mean age of 39.3 ± 21.2 years had been admitted to ED of the studied center in one year (79.2% male. The most common type of dislocation was anterior dislocation (95.8% and in the right shoulder (52.5% and the most common cause was falling on open arm (34.2%. Reduction method was non-operative in 93.3% of the cases and surgery in 6.7%. Based on the results of this study, in the studied population, most patients with shoulder dislocation were young men who had an anterior dislocation in their right shoulder because of falling on out stretched hand and treated with close reduction.

  17. Determination of prevalence of glenoid bony lesions after recurrent anterior shoulder dislocation using the 3-D CT scan

    Guity, Mohamad Reza; Akhlaghpour, Shaharam; Yousefian, Reza

    2014-01-01

    Background: Glenoid bone damages consisting of anterior rim erosion and bony avulsion are very important in decision making for treatment of recurrent dislocation in shoulder joint. This study was aimed to determine the prevalence of these damages in patients with anterior recurrent shoulder dislocation. Methods: The study was a cross-sectional study evaluating patients with unstable shoulder joint. Glenoid bone damage was assessed using three dimensional (CT) scan implementing either glenoid...

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

    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.

  19. 关节镜下盂唇修补与关节囊复合部分肩胛下肌紧缩修复复发性肩关节前脱位%Arthroscopic glenoid labrum repair and combined joint capsule and partial subscapularis suture for recurrent anterior shoulder dislocation

    徐斌; 涂俊

    2015-01-01

    BACKGROUND:Arthroscopic glenoid labrum repair is the main therapy for recurrent anterior shoulder dislocation, which cannot meet the demands of shoulder stability. How to strengthen the anterior shoulder stability is an issue that is always explored and pursued. OBJECTIVE:To explore the effectiveness of arthroscopic glenoid labrum repair and combined joint capsule and partial subscapularis suture for recurrent anterior shoulder dislocation. METHODS:Seventy patients admitted for recurrent anterior shoulder dislocation at the Department of Orthopedics, First Affiliated Hospital of Anhui Medical University in China from October 2010 to August 2013 were enroled, who received the arthroscopic glenoid labrum repair and combined joint capsule and partial subscapularis suture. Patients undergoing post-operative systematical rehabilitation were folowed up for Constant-Murley Score and the ROWE Score for Instability, and shoulder stability and motor functions were evaluated in patients. RESULTS AND CONCLUSION: The 70 patients were folowed-up for 11-46 months. Complications only appeared in one patient with acute pulmonary edema and five patients with elbow or forearm skin blisters, but al were cured by treatment. Anterior shoulder dislocation disappeared postoperatively in al patients. Sixty-five patients almost recovered in the range of motion of the shoulder, who were satisfied with normal life and work activity. Al the patients returned to work. At the last folow-up, the Constant-Murley score was improved from 71.2±5.3 to 94.3±4.9, and the ROWE score was increased from 32.1±4.2 to 95.1±4.7, both of which were better than before (P < 0.05). This study demonstrated arthroscopic glenoid labrum repair and combined joint capsule and partial subscapularis suture is better for recurrent anterior shoulder dislocation, which is conductive to shoulder stability and motor function recovery.%背景:复发性肩关节前脱位的修复目前以关节镜下盂唇修补为主,

  20. Fractures and dislocations of the midfoot: Lisfranc and Chopart injuries.

    Benirschke, Stephen K; Meinberg, Eric G; Anderson, Sarah A; Jones, Clifford B; Cole, Peter A

    2013-01-01

    The midfoot is a complex association of five bones and many articulations between the forefoot metatarsals and the talus and calcaneus, which make up the hindfoot. These anatomic relationships are connected and restrained by an even more complex network of ligaments, capsules, and fascia, which must function as a unit to provide normal and painless locomotion. The common eponyms of Lisfranc and Chopart refer to the distal and proximal joint relationships of the midfoot, respectively. Midfoot injuries range from single ligament strains to complicated fracture-dislocations involving multiple bones and joints. To provide best outcomes for patients, it is important to understand the anatomy and the mechanical function of the midfoot; to review the epidemiology, mechanism, and classification of injuries encountered in an orthopaedic clinical practice; and to review the principles, indications, and surgical techniques for managing midfoot fractures and dislocations. PMID:23395016

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

    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.

  2. Moving Dislocations in Disordered Alloys.

    Marian, J; Caro, A

    2006-11-18

    Using atomistic simulations of dislocation motion in Ni and Ni-Au alloys we report a detailed study of the mobility function as a function of stress, temperature and alloy composition. We analyze the results in terms of analytic models of phonon radiation and their selection rules for phonon excitation. We find a remarkable agreement between the location of the cusps in the {sigma}-v relation and the velocity of waves propagating in the direction of dislocation motion. We identify and characterize three regimes of dissipation whose boundaries are essentially determined by the direction of motion of the dislocation, rather than by its screw or edge character.

  3. Patellar Dislocations and Reduction Procedure.

    Ramponi, Denise

    2016-01-01

    Acute patellar dislocations are a common injury occurring in adolescents involved in sports and dancing activities. This injury usually occurs when the knee is in full extension and sustains a valgus stress on the knee. The medial patellofemoral ligament is the medial restraint that assists in stabilizing the patella from lateral dislocations. The patella usually dislocates laterally and is usually not difficult to reduce after patient evaluation and prereduction radiographs. After postreduction radiographs confirm proper position of the patella postreduction and the absence of fractures, the patient is usually treated conservatively with initial immobilization, orthopedic referral, and physical therapy. PMID:27139130

  4. An Alternate Conservative Management of Shoulder Dislocations and Subluxations

    Sawa, Thomas M.

    1992-01-01

    This paper presents clinical observations/results of the application of an alternate method to traditional conservative management of subluxations and dislocations of the glenohumeral joint on major junior hockey players. The proposed program involves three stages: 1) rest and nutrition, 2) interferential current and faradic muscle stimulation, and 3) a traditional progressive-resistance weight-training program in conjunction with a specially designed orthosis. Current scientific theory on so...

  5. Dislocation of the ulnar nerve at the elbow in an elite wrestler

    Molnar, Szabolcs Lajos; Lang, Peter; Skapinyecz, János; Shadgan, Babak

    2011-01-01

    Dislocation of the ulnar nerve is uncommon among the general population, but it has been reported more frequently in athletes who use their upper limbs to make forceful and resisted flexion of elbow joint. The authors report a unique case of ulnar nerve dislocation in an elite wrestler treated by partial epicondylectomy and subcutaneous transposition of the ulnar nerve. Following the surgery, a supervised and well-designed sport-specific rehabilitation program is a necessary requirement for a...

  6. Management and Prognostic Factors for Delayed Reconstruction of Neglected Posterior Shoulder Fracture-Dislocation

    Bekmezci; Altan

    2015-01-01

    Introduction Posterior fracture-dislocations of the shoulder are rare conditions. Misdiagnosis can occur in 50% - 80% of the patients. Due to the size of the lesion, stability of the joint could not be achieved with transfer of subscapular tendon or tuberosity. Case Presentation A 54-year-old male patient was referred to our hospital with a neglected posterior shoulder fracture-dislocation. Functional results of the patient, and t...

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

    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.

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

    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

  9. Joint swelling

    Swelling of a joint ... Joint swelling may occur along with joint pain . The swelling may cause the joint to appear larger or abnormally shaped. Joint swelling can cause pain or stiffness. After an ...

  10. Avaliação do tratamento cirúrgico da fratura-luxação de Lisfranc Evaluation of the surgical treatment of Lisfranc joint fracture-dislocation

    Cléber de Jesus Pereira

    2008-01-01

    Full Text Available Estudo retrospectivo de 19 casos de fratura-luxação de Lisfranc tratados cirurgicamente no período de 1995 a 2003. O tempo de acompanhamento foi de 35 meses (variando de 4 a 97 meses. O tratamento cirúrgico foi realizado no dia do trauma em 14 casos, com média de demora de 4,78 horas. Ocorreram 5 lesões expostas (36,32% e 5 pacientes foram vítimas de politraumatismo. O mecanismo de lesão mais freqüente foi o acidente motociclístico, seguido da queda de animais e de altura. Utilizou-se a avaliação funcional proposta pela AOFAS (The American Orthopaedic Foot And Ankle Society, que apresentou média de 77,53 (variou de 44 a 100. Houve relação entre a qualidade da redução obtida e o resultado do tratamento (p = 0,0449 e entre o fato do pacientes ser vítima de politraumatismo e um resultado inferior do escore AOFAS (p= 0.0143. Houve como complicação a presença de Osteoartrose em 8 casos (42,10%, confirmando-a como a principal complicação radiográfica destas lesões. Sua ocorrência foi analisada comparando-se com a qualidade da redução e com os diferentes tipos de lesão (exposta,lesão ligamentar ou fratura, se lesão isolada ou politraumatismo não encontrando relação com significância estatística (p This was a retrospective study of 19 cases of Lisfranc fracture-dislocation surgically treated during the period of 1995 - 2003. The follow-up period was 35 months (range: 4 - 97 months. Surgical treatment was provided on the day of the injury in 14 cases, taking an average of 4.78 hours. There were 5 open injuries (36.32% and 5 patients experienced multiple injuries. The most frequent mechanisms of injury were motorcycle accidents, followed by falls from animals, and high falls. The functional evaluation proposed by AOFAS (The American Orthopaedic Foot and Ankle Society was employed, which reported an average of 77.53 (ranging from 44 to 100. A correlation was found between the quality of the reduction achieved and

  11. Position of the prosthesis and the incidence of dislocation following total hip replacement

    HE Rong-xin; YAN Shi-gui; WU Li-dong; WANG Xiang-hua; DAI Xue-song

    2007-01-01

    Background Dislocation is the second most common complication of hip replacement surgery, and impact of the prosthesis is believed to be the fundamental reason. The present study employed Solidworks 2003 and MSC-Nastran software to analyze the three dimensional variables in order to investigate how to prevent dislocation following hip replacement surgery.Methods Computed tomography (CT) imaging was used to collect femoral outline data and Solidworks 2003 software was used to construct the cup model with variabilities. Nastran software was used to evaluate dislocation at different prosthesis positions and different geometrical shapes. Three dimensional movement and results from finite element method were analyzed and the values of dislocation resistance index (DRI), range of motion to impingement (ROM-I),range of motion to dislocation (ROM-D) and peak resisting moment (PRM) were determined. Computer simulation was used to evaluate the range of motion of the hip joint at different prosthesis positions.Results Finite element analysis showed: (1) Increasing the ratio of head/neck increased the ROM-I values and moderately increased ROM-D and PRM values. Increasing the head size significantly increased PRM and to some extent ROM-I and ROM-D values, which suggested that there would be a greater likelihood of dislocation. (2) Increasing the anteversion angle increased the ROM-I, ROM-D, PRM, energy required for dislocation (ENERGY-D) and DRI values,which would increase the stability of the joint. (3) As the chamber angle was increased, ROM-I, ROM-D, PRM, Energy-D and DRI values were increased, resulting in improved joint stability. Chamber angles exceeding 55(°-) resulted in increases in ROM-I and ROM-D values, but decreases in PRM, Energy-D, and DRI values, which, in turn, increased the likelihood of dislocation. (4) The cup, which was reduced posteriorly, reduced ROM-I values (2.1-5.3(°-)) and increased the DRI value (0.073). This suggested that the posterior high side

  12. Simultaneous bilateral anterior shoulder dislocation: report of two cases and review of the literature

    Tripathy Sujit Kumar

    2012-02-01

    Full Text Available 【Abstract】Bilateral shoulder dislocations are rare and almost always occur in the posterior direction. Simultaneous bilateral anterior shoulder dislocation is even rarer and only a few cases are stated in the literature. The most interesting part of a bilateral shoulder dislocation is about its injury mechanism as a synchronous and simultaneous force is needed to result in it. In cases of epilepsy or electrocution, the mechanism is different and the forceful contractions of the selective group of muscles result in the dislocation. This article reports two cases of bilateral simultaneous anterior shoulder joint dislocation that occurred after a road side accident and after an episode of convulsion in an epileptic patient. The dislocations were diagnosed early and reduced immediately with a proper postreduction rehabilitation. During their follow-up, both patients had sa-tisfactory functional outcome. This article emphasizes on the importance of shoulder examination in road side accident victims and epileptic patients. All orthopedic surgeons and emergency physicians should be aware of such unusual possibilities to have an early diagnosis and treatment. An early reduction and appropriate rehabilitation can provide satisfactory functional outcome. This article also briefly discusses the injury mechanisms, diagnoses and treatments of bilateral shoulder dislocation as reported in the literature. Key words: Shoulder dislocation; Epilepsy; Accidents, traffic

  13. The value on high frequency ultrasound in the diagnosing of congenital dislocation and dysplasia of the hip joint of infant%高频超声在婴幼儿先天性髋关节脱位和发育不良中的诊断价值

    李志威

    2011-01-01

    Objective: To explore the clinical value on high frequency ultrasound in the diagnosing of congenital dislocation and dysplasia of the hip joint of infants to offer help for clinical diagnosis and treatment. Methods: 421 infants (842 hips) who were under the age seven months were examined by Graf method of ultrasound examination in hip joint. The hip joint was classified with Graf method by observing the skeletal dysplasia, skeletal dysplasia boundary, soft skeletal dysplasia morphology, angels a and p. Results: Among 421 infants (842 hips) who were under the age of seven months, and there were 370 cases (740 hips) to be normal, there were 14 cases (28 hips) suffered from congenital subluxation of hip, 8 cases (16 hips) suffered from congenital dislocation of hip, 29 cases (58 hips) suffered from contracted congenital dysplasia of hip. Conclusion: Ultrasonic has the advantages of non-invasive and no radiation, what's more, it's convenient to use for checking, and with no contraindication, and it can be applied repeatedly. It is the first choice as screening for the infants, and it can help observing the effect of the clinical therapy.%目的:探索高频超声在婴幼儿先天性髋关节脱位和发育不良诊断中的临床价值,为临床的诊断治疗提供帮助.方法:对421例7个月以内的婴幼儿(842个髋关节)行Graf法髋关节超声检查,通过观察骨性髋臼、骨性髋臼外侧缘、软骨性髋臼形态及测量α、β角,对髋关节进行Graf分型,探讨高频超声作为新生儿髋关节发育不良筛查的诊断工具对临床治疗效果进行动态观察的价值.结果:检查7个月以下婴幼儿421例(842个髋关节),其中,正常髋关节370例(740个髋关节),婴幼儿先天性髋关节半脱位14例(28个髋关节),全脱位8例(16个髋关节),发育不良29例(58个髋关节).结论:超声波具有无创、无射线的特性,且检查方便,无禁忌证,可以重复应用,可作为对新生儿进行筛查工作的首

  14. Posterior sternoclavicular Salter-Harris fracture-dislocation in a patient with unossified medial clavicle epiphysis.

    Beckmann, Nicholas; Crawford, Lindsay

    2016-08-01

    Sternoclavicular injuries are relatively rare, composing less than 1 % of all musculoskeletal fractures or dislocations. When sternoclavicular injuries do occur, they typically present as an isolated dislocation of the sternoclavicular joint without associated fracture of the clavicle or manubrium. However, in patients with unfused medial clavicle physis, sternoclavicular joint injuries can present as a fracture-dislocation through the unfused physis. These physeal injuries are important to recognize as the displaced epiphysis can block reduction of the sternoclavicular joint. We present a case of a 15-year-old female basketball player presenting with suspected sternoclavicular joint injury after sustaining a direct blow to the left shoulder. An initial shoulder CT confirmed the presence of the clinically suspected posterior sternoclavicular dislocation without fracture identified. An MRI of the left sternoclavicular joint was then performed for suspected physeal fracture, which confirmed the presence of a fracture through the medial clavicle physis with anterior displacement of the unossified epiphysis, blocking reduction of the metaphysis. Given the findings on MRI, the pediatric orthropedic surgeon was able to counsel the family of the high likelihood of failed closed reduction of the sternoclavicular joint requiring conversion to open reduction and internal fixation. The patient underwent successful open reduction and internal fixation of the medial clavical physeal fracture after an initial gentle attempt at closed reduction was unsuccessful. PMID:27107998

  15. Management of dislocated intraocular implants.

    Chan, C K; Agarwal, A; Agarwal, S; Agarwal, A

    2001-12-01

    Implant dislocation may occur in the absence of appropriate capsular or zonular support (PCIOL) (11,35,53) or following traumatic injury to anterior ocular tissues (ACIOL). (11,19,20) Other factors (e.g., advanced patient age, high myopia, previous vitrectomy, pseudoexfoliation syndrome, and certain connective tissue disorders) also may predispose implant dislocation. (9,52) Although reported for all types of IOLs, implant dislocation is becoming more manageable because of the advancement of surgical techniques. A dislocated ACIOL or PCIOL may be explanted, exchanged, or repositioned. (11,48,71) Repositioning the dislocated PCIOL in the ciliary sulcus with modern vitreoretinal techniques provides an optimal environment for visual recovery. (11,71) Implant repositioning techniques generally may be categorized into the external or the internal approaches. (8,11) The former involves external suturing methods for a primary or secondary implant in the absence of adequate capsular or zonular support (15,16,31,42,56,60,61,64,66,73,76) and the latter is achieved through modern pars plana techniques. 8,11,62,69) Recently, several implant repositioning methods gaining increasing acceptance include the scleral loop fixation, (45) the snare approach, (43) the use of the 25-gauge implant forceps, (13) temporary haptic externalization, (8,11,36,71) and the use of perfluorocarbon liquids. (1,28,40,41,44) The temporary haptic externalization method combines the best features of the external and the internal approaches, avoids complex intraocular maneuvers, and allows precise scleral fixation of the dislocated IOL on a consistent basis. (8,11,71) Endoscopy provides the surgeon with optimal viewing of the anterior retropupillary anatomy that is often difficult to appreciate (e.g., capsular-zonular complex, ciliary sulcus, anterior retina, and vitreous base). (6,11) As a result, precise haptic placement is possible during the repositioning process. (6,11) However, a three

  16. Dislocations in Monolayers and Semiconductors.

    Ren, Qiang

    1995-01-01

    Four different aspects of the properties of dislocations in monolayer and semiconductors have been investigated: (i) Using atomic relaxation techniques, dislocation dipoles of various sizes and orientations have been studied for monolayers with the Lennard-Jones potential (LJP) and the nearest-neighbour piecewise linear force (PLF) interactions. In the WP system the lower energy vacancy dipoles have over a wide range of angles an energy which is mainly a function of the vacancy content of the dipole. There is a competition between the elastic forces and the topological constraints which favour a five-fold coordinate vacancy (FCV) at the centre of each core. For the short range PLF system the lattice usually compresses upon the introduction of a dislocation, a consequence of the soft core of the interaction potential, and interstitial dipoles are lower in energy. For the long range LJP system the dislocations are mobile whereas for the PLF system they are pinned. The relevance of these results to existing theories of melting are discussed. (ii) Using generalized stacking-fault (GSF) energies obtained from first-principles density-functional calculations, a zero-temperature model for dislocations in silicon is constructed within the framework of a Peierls-Nabarro (PN) model. Core widths, core energies, PN pinning energies, and stresses are calculated for various possible perfect and imperfect dislocations. Both shuffle and glide sets are considered. 90^circ partials are shown to have a lower Peierls stress (PS) than 30 ^circ partials in accord with experiment. (iii) We have also studied by atomic relaxation techniques the properties of dislocations in silicon, modelled by the empirical potential of Stillinger and Weber. In order to compare with the preceding calculation no reconstruction is allowed. We find no evidence of dissociation in the shuffle dislocations. Within this model shuffle dislocations glide along their slipping planes. On the other hand, glide sets

  17. Injuries and treatment of the Lisfranc s joint

    Gorgec, Mucahit; Esenkaya, Irfan; Nalbantoglu, Ufuk; Turkmen, Metin

    2004-01-01

    Lisfranc s joint is a stabil joint its injuries are very rare. During the period of March 1990 to June 1993, 21 patients with Lisfranc s fracture dislocations were treated. They were classified according to Quenu and Kuss classification as: 11 totallateral, 1 partial medial, 3 partiallateral, 3 partial divergent and 3 total divergent dislocations. Closed reduction and Kirschner wire fixation was performed a of them, open reduction and Kirschner wire fixation performed 10 of them and open redu...

  18. A hinged external fixator for complex elbow dislocations: A multicenter prospective cohort study

    Verleisdonk Egbert JMM

    2011-06-01

    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 of the radial head, olecranon, or coronoid process. The majority of patients with these complex dislocations are treated with open reduction and internal fixation (ORIF, or arthroplasty in case of a non-reconstructable radial head fracture. If the elbow joint remains unstable after fracture fixation, a hinged elbow fixator can be applied. The fixator provides stability to the elbow joint, and allows for early mobilization. The latter may be important for preventing stiffness of the joint. The aim of this study is to determine the effect of early mobilization with a hinged external elbow fixator on clinical outcome in patients with complex elbow dislocations with residual instability following fracture fixation. Methods/Design The design of the study will be a multicenter prospective cohort study of 30 patients who have sustained a complex elbow dislocation and are treated with a hinged elbow fixator following fracture fixation because of residual instability. Early active motion exercises within the limits of pain will be started immediately after surgery under supervision of a physical therapist. Outcome will be evaluated at regular intervals over the subsequent 12 months. The primary outcome 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, radiographic healing of the fractures and formation of periarticular ossifications, rate of secondary interventions and complications, and health-related quality of life (Short-Form 36. Discussion The outcome of this study will yield quantitative data on the functional outcome in patients with a complex elbow dislocation and who are

  19. Mycobacterium avium-intracellulare cellulitis occurring with septic arthritis after joint injection: a case report

    Murdoch David M

    2007-02-01

    Full Text Available Abstract Background Cellulitis caused by Mycobacterium avium-intracellulare has rarely been described. Mycobacterium avium-intracellulare is a rare cause of septic arthritis after intra-articular injection, though the causative role of injection is difficult to ascertain in such cases. Case presentation A 57-year-old with rheumatoid arthritis treated with prednisone and azathioprine developed bilateral painful degenerative shoulder arthritis. After corticosteroid injections into both acromioclavicular joints, he developed bilateral cellulitis centered over the injection sites. Skin biopsy showed non-caseating granulomas, and culture grew Mycobacterium avium-intracellulare. Joint aspiration also revealed Mycobacterium avium-intracellulare infection. Conclusion Although rare, skin and joint infections caused by Mycobacterium avium-intracellulare should be considered in any immunocompromised host, particularly after intra-articular injection. Stains for acid-fast bacilli may be negative in pathologic samples even in the presence of infection; cultures of tissue specimens should always be obtained.

  20. Dislocations and other topological oddities

    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.

  1. Patellar dislocation with genu valgum treated by DFO.

    Kwon, Jae Ho; Kim, Jong In; Seo, Dong-Hyun; Kang, Kyung-Woon; Nam, Ji Ho; Nha, Kyung-Wook

    2013-06-01

    Congenital habitual patellar dislocation is a rare condition of the knee where the patella dislocates during flexion and relocates during extension. The congenital form is permanent, irreducible, and presents at birth. It is characterized by a short quadriceps and a major patellofemoral dysplasia and short height. This article presents a rare case of a 27-year-old woman with recurring bilateral habitual dislocation of the patella after a failed previous proximal and distal realignment procedure. Clinical examinations of both knees revealed genu valgus knees and lateral joint pain that recurred after several previous operations. Radiographs of both knees showed patellar dislocation and genu valgum associated with patellofemoral dysplasia and osteoarthritis of the lateral compartment. Long-leg standing radiographs showed an anatomic tibiofemoral angle of right 13° and left 6° valgus and a mechanical tibiofemoral angle of right 8° and left 2° valgus and weight-bearing line of 65% on the right and 48% on the left. The authors performed a distal femoral closing wedging osteotomy to correct the valgus deformity, and then percutaneous lateral release and medial reefing were performed to stabilize the patellas of both knees simultaneously. PMID:23746026

  2. Arthroplasty versus arthroscopy for recurrent anterior dislocation of the shoulder joint with severe bone defects:3-year follow-up%关节置换与关节镜下修复肩关节复发性前脱位伴重度骨缺损:3年随访对比

    陈辉; 王群; 燕双喜; 董天云; 邹海兵

    2015-01-01

    背景:随着外科技术、重建材料技术的发展,关节置换在肩关节脱位中也得到了广泛应用,特别是各种定制型或装配型假体使得置换适应证明显提高。  目的:观察与随访关节镜与关节置换治疗肩关节复发性前脱位伴重度骨缺损的远期疗效。  方法:纳入肩关节复发性前脱位伴重度骨缺损患者144例,根据随机抽签分为治疗组与对照组,每组72例。对照组行关节镜下内固定治疗,治疗组行关节置换治疗。通过电话调查与复诊完成3年随访,记录患者Neer肩关节功能评分、肩关节活动度及并发症发生情况。  结果与结论:随访3年,治疗组的肩关节功能优良率90%明显高于对照组81%(P RESULTS AND CONCLUSION:After 3-year fol owed-up, the excel ent and good rate of shoulder function was significantly higher in the treatment group (90%) than in the control group (81%) (P<0.05). The magnitude of the flexion in the 3-year fol owed-up was apparently increased, while the lateral margin external rotation was decreased, which showed significant differences after intragroup comparison (P<0.05). Simultaneously, the magnitude of the flexion and the lateral margin external rotation in the treatment group had statistical y significant differences compared to the control group in the 3-year fol owed-up (P<0.05). The complications of wound infection, shoulder dislocation, and implant loosening in the treatment group during fol ow-up were significantly lower than in the control group (P<0.05). These findings verified that compared with arthroscopic surgery, arthroplasty for treating recurrent anterior dislocation of the shoulder joint with severe bone defects in long-term fol ow-up can effectively restore shoulder function and range of motion, and it has few complications, thereby effectively rebuilds shoulder joint.

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

    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

  4. Tarsometatarsal/Lisfranc joint.

    DiDomenico, Lawrence A; Cross, Davi

    2012-04-01

    Accurate early diagnosis with adequate reduction and maintenance of anatomic alignment of the dislocation or fracture within the Lisfranc joint complex have been found to be the key to successful outcomes regarding this injury. Because of the anatomic variations, the thin soft tissue envelop, and the abundance of ligamentous and capsular structures in the region, repair of these injuries can be a challenge. The classification systems used to describe these injuries aid in describing the mechanism of injury or displacement type present, which may aid in determining what treatment modality can provide the best outcome. PMID:22424486

  5. Simultaneous bilateral anterior shoulder dislocation: report of two cases and review of the literature

    Sujit Kumar Tripathy; Ramesh Kumar Sen; Sameer Aggarwal; Sarvdeep Singh Dhatt; Naveen Tahasildar

    2011-01-01

    Bilateral shoulder dislocations are rare and almost always occur in the posterior direction. Simultaneous bilateral anterior shoulder dislocation is even rarer and only a few cases are stated in the literature. The most interesting part of a bilateral shoulder dislocation is about its injury mechanism as a synchronous and simultaneous force is needed to result in it. In cases of epilepsy or electrocution, the mechanism is different and the forceful contractions of the selective group of muscles result in the dislocation. This article reports two cases of bilateral simultaneous anterior shoulder joint dislocation that occurred after a road side accident and after an episode of convulsion in an epileptic patient. The dislocations were diagnosed early and reduced immediately with a proper postreduction rehabilitation. During their follow-up, both patients had satisfactory functional outcome. This article emphasizes on the importance of shoulder examination in road side accident victims and epileptic patients. All orthopedic surgeons and emergency physicians should be aware of such unusual possibilities to have an early diagnosis and treatment.An early reduction and appropriate rehabilitation can provide satisfactory functional outcome. This article also briefly discusses the injury mechanisms, diagnoses and treatments of bilateral shoulder dislocation as reported in the literature.

  6. Bilateral inferior dislocation of the hip——a case report

    Kishan R Bhagwat; Bhavuk Garg; Sameer Aggarwal; Mandeep S Dhillon

    2012-01-01

    Inferior dislocation of the hip is the rarest type in hip dislocation.Very few cases have been reported in the anglophonic literature,most of which involved the pediatric age group.Surprisingly,we came across a 30-year-old patient with a bilateral inferior hip dislocation.He had sustained a road traffic accident and the attitude of both hip joints was flexion and abduction.The diagnosis was confirmed by radiographs which revealed the long axis of the femur at an angle of 110 (fight) degrees and 100 (left) degrees respectively away from the axis.Closed reduction under sedation was successfully performed.Skin traction for a period of 6 weeks was advised and the follow-up revealed an excellent result.We present the details of this case,the first of its kind along with a review of the literature,discussing the various modes and mechanisms of injury inducing inferior dislocation of the hip.

  7. Subtalar dislocation secondary to a low energy injury.

    McKeag, Philip; Lyske, Jonathan; Reaney, Jonathan; Thompson, Neville

    2015-01-01

    An 18-year-old young man presented with an ankle injury, after landing on a supinated right foot following jumping while playing football. A plain X-ray revealed a medial subtalar dislocation. Despite obvious ankle deformity, the surrounding skin remained intact. Closed reduction of the subtalar joint was successfully performed under general anaesthesia in theatre. A CT of the ankle, after reduction, demonstrated a non-displaced fracture of the neck of the talus; no osteochondral defect was observed. This was successfully managed conservatively, with immobilisation of the ankle, in a non-weight bearing cast for 6 weeks. This case highlights that subtalar dislocation may follow a low-energy mechanism and that such injuries can be managed without open reduction. PMID:25650063

  8. Light scattering from dislocations in silicon

    Monier, Vanessa; Capello, Luciana; Kononchuk, Oleg; Pichaud, Bernard

    2010-11-01

    Nondecorated glide dislocations in Czochralski grown silicon have been studied by laser scattering tomography technique. Dependence of intensity of scattered light on polarization of the incident light has been measured for different orientations of the dislocation line and Burgers vector. Detailed theory of light scattering by dislocation in silicon crystals is presented. It is shown that by combination of polarization and tomography measurements it is possible to determine slip system of nondecorated mixed dislocation in Si.

  9. Intermittent dislocation flow in viscoplastic deformation

    Miguel, M. -Carmen; Vespignani, Alessandro; Zapperi, Stefano; Weiss, Jerome; Grasso, Jean-Robert

    2001-01-01

    The viscoplastic deformation (creep) of crystalline materials under constant stress involves the motion of a large number of interacting dislocations. Analytical methods and sophisticated `dislocation-dynamics' simulations have proved very effective in the study of dislocation patterning, and have led to macroscopic constitutive laws of plastic deformation. Yet, a statistical analysis of the dynamics of an assembly of interacting dislocations has not hitherto been performed. Here we report ac...

  10. Drift of dislocation tripoles under ultrasound influence.

    Murzaev, R T; Bachurin, D V; Nazarov, A A

    2016-01-01

    Numerical simulations of dynamics of different stable dislocation tripoles under influence of monochromatic standing sound wave were performed. The basic conditions necessary for the drift and mutual rearrangements between dislocation structures were investigated. The dependence of the drift velocity of the dislocation tripoles as a function of the frequency and amplitude of the external influence was obtained. The results of the work can be useful in analysis of motion and self-organization of dislocation structure under ultrasound influence. PMID:26278625

  11. Bilateral fracture dislocation of the shoulder (Presentation of a Case)

    Kuzgun, Unal; Baskir, Orhan; Temelli, Yener; Yazicioglu, Onder; Temocin, Bahattin O.; Kokino, Misel

    2004-01-01

    The largest portion of the dislocations encountered in the adults comprises shoulder dislocations and 2.16% of these dislocations constitute posterior dislocations. It is possible to detect that a dislocation develops secondary to convulsions due to immediate loss of consciousness in the history of most of the posterior dislocations of the shoulder. Approximately 20 cases have been so far reported in literature regurding bilateral dislocations of the shoulder. Bilateral dislocation associated...

  12. Traumatic Knee Dislocation with Acute Artery Injury

    Hüseyin Şahin1; Mustafa Uzkeser2; Ayhan Aköz; et al.

    2014-01-01

    Traumatic knee dislocation is very rare injury in patients presenting to the emergency room. The complications associated with knee dislocation such as amputation of extremities and die is required emergency response. We discussed a case, that he has only knee dislocation and popliteal artery injury and mortal as soon as possible.

  13. A Galeazzi-variant type fracture-dislocation in adults

    Raju Vaishya; Sundar Kumar Shrestha; Abhishek Vaish

    2013-01-01

    Objective:Fracture of either radius or ulna with a dislocation either at the proximal or distal radioulnar joint (DRUJ) is not a common injury and is inherently unstable.Here we report a case series,with both-bone forearm fractures associated with dislocation of DRUJ,as a Galeazzi-variant type fracture-dislocation,and try to analyze this injury pattern.Methods:The study was based on 6 patients having Galeazzi-variant type fracture-dislocation of different age (20 to 45 years).All fractures were closed type.Two fractures involved the same level and three fractures were at different levels of radius and ulna shaft.After thorough examination and investigations they were treated with limited contact dynamic compression plate without additional fixation for DRUJ.Results:All cases were followed up for 24 weeks.The maximum incidence occurred in age group between 31 and 40 years.All the fractures of both radius and ulna were united in average time of 12 weeks.Range of motion of wrist and elbow,supination and pronation at final follow-up were normal.There was no subsequent re-subluxation or dislocation of the DRUJ in any of the cases.Conclusion:Galeazzi variant in adult is a new undescribed pattern of forearm with wrist injury.Stable open reduction and internal fixation of both-bone forearm fractures is mandatory,followed by 3 to 4 weeks of immobilization in a cast for the healing of disrupted DRUJ.

  14. Scattering of phonons by dislocations

    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. = 109 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

  15. Metal working and dislocation structures

    Hansen, Niels

    2007-01-01

    Microstructural observations are presented for different metals deformed from low to high strain by both traditional and new metal working processes. It is shown that deformation induced dislocation structures can be interpreted and analyzed within a common framework of grain subdivision on a finer...... metals with structures on the scale from about 10 nm to 1 mu m....

  16. Arthroscopic findings after shoulder dislocation

    Medenica Ivica; Radunović Aleksandar; Madžarac Dragan; Zorić Miodrag; Bokonjić Dubravko; Stojković Bratislav

    2009-01-01

    Background/Aim. Recurrent instability of the shoulder joint is frequently difficult to differentiate from diseased or injured rotator cuff or tendon of the forearm flexor (m. biceps brachii). Shoulder joint arthroscopy has been only recently introduced into instable shoulder joint lesion examination. The aim of this study was to present and analyze an arthroscopic finding on instable shoulder joint in order to determine causes and mechanisms of instability, as well as principles of surgical t...

  17. The temporomandibular joint

    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

  18. Distal radioulnar joint injuries.

    Thomas, Binu P; Sreekanth, Raveendran

    2012-09-01

    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. PMID:23162140

  19. Distal radioulnar joint injuries

    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.

  20. Posterior dislocation of the elbow as an unusual presentation after a total hip replacement: a case report

    Periasamy Kumar

    2008-02-01

    Full Text Available Abstract Introduction Posterior dislocation of the elbow is usually associated with trauma to the joint with a reported incidence of 3%to 6%. Chronic instability is usually symptomatic following the initial injury. Case presentation We report a case of posterior dislocation of the elbow occurring in a patient while using her arm to lift herself using a monkey pole on the second day following a total hip replacement. The dislocation was reduced under sedation in the ward. There were no signs or symptoms suggesting any joint hypermobility syndrome in the patient. Follow up 4 months following the injury revealed a complete recovery in the range of motion and a pain free elbow. There were no signs and symptoms of any instability. Conclusion This is the first time such a case is reported in the literature. It certainly demonstrates that even in the absence of instability a patient can be predisposed to low energy dislocation of the elbow.

  1. Atomistic simulations of dislocation processes in copper

    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 of...

  2. Slip systems, lattice rotations and dislocation boundaries

    Winther, Grethe

    of dislocation structure formed, in particular the crystallographic alignment of dislocation boundaries, and the slip pattern are demonstrated. These relations are applied to polycrystals deformed in tension and rolling, producing good agreement with experiment for rolling but less good agreement for......Plastic deformation by slip induces rotations of the crystallographic lattice and evolution of dislocation structures. Both lattice rotations and dislocation structures exhibit a dependence on the grain orientation, which reflects underlying relations to the slip pattern. Relations between the type...... these discrepancies is discussed. Finally, the implications of the relations between slip and dislocation structures for the modelling of mechanical properties are discussed....

  3. Kinetic Monte Carlo simulation of dislocation dynamics

    A kinetic Monte Carlo simulation of dislocation motion is introduced. The dislocations are assumed to be composed of pure edge and screw segments confined to a fixed lattice. The stress and temperature dependence of the dislocation velocity is studied, and finite-size effects are discussed. It is argued that surfaces and boundaries may play a significant role in the velocity of dislocations. The simulated dislocations are shown to display kinetic roughening according to the exponents predicted by the Kardar-Parisi-Zhang equation. copyright 1999 The American Physical Society

  4. Solute drag on perfect and extended dislocations

    Sills, R. B.; Cai, W.

    2016-04-01

    The drag force exerted on a moving dislocation by a field of mobile solutes is studied in the steady state. The drag force is numerically calculated as a function of the dislocation velocity for both perfect and extended dislocations. The sensitivity of the non-dimensionalized force-velocity curve to the various controlling parameters is assessed, and an approximate analytical force-velocity expression is given. A non-dimensional parameter S characterizing the strength of the solute-dislocation interaction, the background solute fraction ?, and the dislocation character angle ?, are found to have the strongest influence on the force-velocity curve. Within the model considered here, a perfect screw dislocation experiences no solute drag, but an extended screw dislocation experiences a non-zero drag force that is about 10 to 30% of the drag on an extended edge dislocation. The solutes can change the spacing between the Shockley partials in both stationary and moving extended dislocations, even when the stacking fault energy remains unaltered. Under certain conditions, the solutes destabilize an extended dislocation by either collapsing it into a perfect dislocation or causing the partials to separate unboundedly. It is proposed that the latter instability may lead to the formation of large faulted areas and deformation twins in low stacking fault energy materials containing solutes, consistent with experimental observations of copper and stainless steel containing hydrogen.

  5. [Anterior dislocation of the fibula resulting from surgical malreduction: a case report].

    Wang, Z Y; Wu, X B

    2016-04-18

    Ankle joint fracture is one of the most common types of fracture. There are many researches on the injury mechanism, treatment principles and surgical techniques. A type of injury which combines posterior dislocation of fibula, known as the Bosworth injury, is relatively rare. In 1947, Bosworth first described this type of injury as an unusual ankle fracture dislocation with fixed posterior fracture dislocation of the distal part of the fibula. In this type of fracture, the proximal fibular shaft fragment locks behind the tibialis posterior tubercle. This rare ankle fracture variant is often not recognized in initial radiographs and requires a computed tomographic (CT) scan for verification. But there are already many reports, discussing the injury mechanism, treatment principles and surgical techniques. However, there are few reports of anterior dislocation of the fibula, caused by either injury or surgery. The mechanism of the injury is still not clear. This article reports a case of anterior dislocation of the fibula. We report a patient with left ankle open fracture (Lauge-Hansen pronation-external rotation stage III, Gustilo IIIA). Open reduction and internal fixation was done in the initial surgery, but ended up with poor reduction, resulting in fibula anterior dislocation, anterior dislocation of talus and tibia fibular dislocation. The fibula was dislocated anteriorly of the tibia, which rarely happened. The patient suffered severe ankle joint dysfunction. The second operation took out the original internal fixation, reduced the fracture, and reset the internal fixation. The function of ankle joint was improved obviously after operation. But because of the initial injury and the two operations, the soft tissue around the fracture was greatly damaged. 6 months after the second operation, and the fracture still not healed, so the bone graft was carried out in the third surgery. Two months after the third surgery, the function of the ankle was significantly

  6. Discrete dislocation dynamics simulations in a cylinder

    Li, Maosheng; Gao, Chan; Xu, Jianing

    2015-02-01

    Mechanical properties of material are closely related to the motion of dislocations, and predicting the interactions and resulting collective motion of dislocations is a major task in understanding and modelling plastically deforming materials. A discrete dislocation dynamics model is used to describe the orientation substructure within the microstructure. Discrete dislocation dynamics simulations in three dimensions have been used to examine the role of dislocation multiplication and mobility on the plasticity in small samples under uniaxial compression. In this paper we describe the application of the dislocation dynamics simulations in a cylindrical geometry. The boundary conditions for the simulation were estimated from the distribution of the geometrically necessary dislocation density which was obtained from the orientation map. Numerical studies benchmark could validate the accuracy of the algorithms and the importance of handling the singularity correctly. The results of the simulation explain the formation of the experimentally observed substructure.

  7. Dislocation motion in tungsten: Atomistic input to discrete dislocation simulations

    Srivastava, K.; Gröger, Roman; Weygand, D.; Gumbsch, P.

    2013-01-01

    Roč. 47, AUG (2013), s. 126-142. ISSN 0749-6419 R&D Projects: GA ČR GAP204/10/0255; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : body-centered cubic * non-Schmid effects * anomalous slip * discrete dislocation dynamics Subject RIV: BM - Solid Matter Physics ; Magnetism; BM - Solid Matter Physics ; Magnetism (UFM-A) Impact factor: 5.971, year: 2013

  8. Evolution of geometrically necessary dislocation density from computational dislocation dynamics

    This paper presents a method for calculating GND densities in dislocation dynamics simulations. Evolution of suitably defined averages of GND density as well as maps showing the spatial nonuniform distribution of GNDs are analyzed under uniaxial loading. Focus is laid on the resolution dependence of the very notion of GND density, its dependence upon physical dimensions of plastically deformed specimens and its sensitivity to initial conditions. Acknowledgments Support from the National Science Foundation (CMMI-0748187) is gratefully acknowledged.

  9. Evolution of geometrically necessary dislocation density from computational dislocation dynamics

    Guruprasad, P J; Benzerga, A A, E-mail: pjguru@tamu.edu, E-mail: benzerga@aero.tamu.edu [Department of Aerospace Engineering, Texas A and M University, College Station, TX 77843-3141 (United States)

    2009-07-15

    This paper presents a method for calculating GND densities in dislocation dynamics simulations. Evolution of suitably defined averages of GND density as well as maps showing the spatial nonuniform distribution of GNDs are analyzed under uniaxial loading. Focus is laid on the resolution dependence of the very notion of GND density, its dependence upon physical dimensions of plastically deformed specimens and its sensitivity to initial conditions. Acknowledgments Support from the National Science Foundation (CMMI-0748187) is gratefully acknowledged.

  10. SIDELINE MANAGEMENT OF ACUTE DISLOCATION OF THE GLENOHUMERAL JOINT‐ A UNIQUE APPROACH TO ATHLETE SELF‐REDUCTION

    Smith, Danny; Hoogenboom, Barbara

    2013-01-01

    The acute anterior dislocation of the glenohumeral joint (GHJ) poses a challenge to sports medicine providers at all levels and in all settings. This macrotraumatic injury occurs in athletes who participate in a wide variety of sports, most typically as a result of contact or collision mechanisms. Quick and effective relocation of the GHJ is an important skill for on the sideline or on the field management of this type of dislocation when appropriate and allowable by facility protocol. This c...

  11. Closed subtalar dislocation with non-displaced fractures of talus and navicular: a case report and review of the literature

    Fotiadis, Elias; Lyrtzis, Christos; Svarnas, Theodoros; Koimtzis, Miltos; Akritopoulou, Kiriaki; Chalidis, Byron

    2009-01-01

    Closed subtalar dislocations associated with talus and navicular fractures are rare injuries. We report on a case of a 43-year-old builder man with medial subtalar dislocation that was further complicated by minimally displaced talar and navicular fractures. Successful closed reduction under general anesthesia was followed by non-weight bearing and ankle immobilization with a below-knee cast for 6 ;weeks. At 3 years post-injury, the subtalar joint was stable, the foot and ankle mobility was i...

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

    Gvozdenovic, R; Vadstrup, Lars Soelberg

    2015-01-01

    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 in the...

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

    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.

  14. Diabetic Lisfranc fracture-dislocations and Charcot neuroarthropathy.

    Levitt, Bradley A; Stapleton, John J; Zgonis, Thomas

    2013-04-01

    The goal with Lisfranc fracture-dislocations is to regain joint congruity and reestablish midfoot stability to avoid debilitating posttraumatic arthrosis and chronic pain in the sensate patient. In the diabetic population, dense peripheral neuropathy and/or vascular disease are equally important and may alter the surgical approach to traumatic tarsometatarsal injuries. The initial diagnosis in the diabetic population may be delayed due to subtle radiographic findings and/or patient unawareness of trauma in the insensate foot. Failure to initiate treatment in the early stages of acute diabetic neuropathic Lisfranc injuries can predispose the patient to midfoot instability, potential ulceration, infection, and Charcot neuroarthropathy. PMID:23465814

  15. Anterior dislocation of shoulder in eclampsia:a case report

    Seema Rawat; Sanjay Meena; Shreesh Kumar Gangari; Lalit Kumar Lohia

    2012-01-01

    This case report presents a 25-year-old female patient with anterior dislocation of right shoulder secondary to seizures as a complication of eclampsia.This is an unusual mechanism of injury,but similar to other uncontrolled muscular contractions caused by electroconvulsive therapy,etc.To the best of our knowledge only one such case has been reported in the English literature.Closed reduction under general anaesthesia was successfully achieved.High suspicion in patients complaining of pain over shoulder joint is necessary for early diagnosis of this condition.

  16. Lattice dislocation in Si nanowires

    Omar, M.S., E-mail: dr_m_s_omar@yahoo.co [Department of Physics, College of Science, University of Salahaddin, Arbil, Iraqi Kurdistan (Iraq); Taha, H.T. [Department of Physics, College of Science, University of Salahaddin, Arbil, Iraqi Kurdistan (Iraq)

    2009-12-15

    Modified formulas were used to calculate lattice thermal expansion, specific heat and Bulk modulus for Si nanowires with diameters of 115, 56, 37 and 22 nm. From these values and Gruneisen parameter taken from reference, mean lattice volumes were found to be as 20.03 A{sup 3} for the bulk and 23.63, 29.91, 34.69 and 40.46 A{sup 3} for Si nanowire diameters mentioned above, respectively. Their mean bonding length was calculated to be as 0.235 nm for the bulk and 0.248, 0.269, 0.282 and 0.297 nm for the nanowires diameter mentioned above, respectively. By dividing the nanowires diameter on the mean bonding length, number of layers per each nanowire size was found to be as 230, 104, 65 and 37 for the diameters mentioned above, respectively. Lattice dislocations in 22 nm diameter wire were found to be from 0.00324 nm for the 1st central lattice to 0.2579 nm for the last surface lattice. Such dislocation was smaller for larger wire diameters. Dislocation concentration found to change in Si nanowires according to the proportionalities of surface thickness to nanowire radius ratios.

  17. 3D Dislocation dynamics modelling of interactions between prismatic loops and mobile dislocations in pure iron

    Novokshanov, Roman [Department of Materials, University of Oxford, Oxford (United Kingdom)], E-mail: novoksha@maths.ox.ac.uk; Roberts, Steve [Department of Materials, University of Oxford, Oxford (United Kingdom)

    2009-04-30

    3D Dislocation dynamics simulations have been carried out to model the interaction between prismatic loops and dislocations in pure iron subject to uniaxial loading conditions. The primary goal was to understand the mechanism of interaction of an a/2 <1 1 1> interstitial loop and a mobile dislocation. The secondary goal was to investigate the dependence of the critical stress needed for dislocations to overcome the obstacles as a function of size of loops and their orientation with respect to the glide plane. The simulations have shown a complicated 3D interaction resulting in the mobile dislocation bowing around a loop, either reacting with the loop dislocation or leaving it behind unchanged.

  18. Visualization of dislocation dynamics in colloidal crystals.

    Schall, Peter; Cohen, Itai; Weitz, David A; Spaepen, Frans

    2004-09-24

    The dominant mechanism for creating large irreversible strain in atomic crystals is the motion of dislocations, a class of line defects in the crystalline lattice. Here we show that the motion of dislocations can also be observed in strained colloidal crystals, allowing detailed investigation of their topology and propagation. We describe a laser diffraction microscopy setup used to study the growth and structure of misfit dislocations in colloidal crystalline films. Complementary microscopic information at the single-particle level is obtained with a laser scanning confocal microscope. The combination of these two techniques enables us to study dislocations over a range of length scales, allowing us to determine important parameters of misfit dislocations such as critical film thickness, dislocation density, Burgers vector, and lattice resistance to dislocation motion. We identify the observed dislocations as Shockley partials that bound stacking faults of vanishing energy. Remarkably, we find that even on the scale of a few lattice vectors, the dislocation behavior is well described by the continuum approach commonly used to describe dislocations in atomic crystals. PMID:15448265

  19. A RARE CASE OF IPSILATERAL HIP AND KNEE DISLOCATION

    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.

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

    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

  1. Dislocation climb in GaAs

    The weak-beam technique of transmission-electron-microscopy is used to investigate dislocation climb in GaAs, a high supersaturation of point defects being introduced by electron irradiation in a high-voltage-electron-microscope. It is shown that, at room temperature, climb of dissociated a/2 dislocations proceeds by nucleation of both Frank and perfect interstitial loops on the individual partials. Irradiation carried out at higher temperature (4500C) showed evidence for the interaction of the new loops with the non-parent partial, leading to climb of the total dislocation. Dislocations of α and β-type, i.e. of opposite edge character, exhibit the same climb mechanism. In this paper, the microscopic mechanism of dislocation climb is analysed and the relevance of this study to the understanding of the degradation of GaAs devices by climbing dislocations is considered

  2. Mobility Laws in Dislocation Dynamics Simulations

    Cai, W; Bulatov, V V

    2003-10-21

    Prediction of the plastic deformation behavior of single crystals based on the collective dynamics of dislocations has been a challenge for computational materials science for a number of years. The difficulty lies in the inability of existing dislocation dynamics (DD) codes to handle a sufficiently large number of dislocation lines, to establish a statistically representative model of crystal plasticity. A new massively-parallel DD code is developed that is capable of modeling million-dislocation systems by employing thousands of processors. We discuss an important ingredient of this code--the mobility laws dictating the behavior of individual dislocations. They are materials input for DD simulations and are constructed based on the understanding of dislocation motion at the atomistic level.

  3. Mobility laws in dislocation dynamics simulations

    Cai, Wei; Bulatov, Vasily V

    2004-12-15

    Prediction of the plastic deformation behavior of single crystals based on the collective dynamics of dislocations has been a challenge for computational materials science for a number of years. The difficulty lies in the inability of existing dislocation dynamics (DD) codes to handle a sufficiently large number of dislocation lines, to establish a statistically representative model of crystal plasticity. A new massively parallel DD code is developed that is capable of modeling million-dislocation systems by employing thousands of processors. We discuss an important ingredient of this code - the mobility laws dictating the behavior of individual dislocations. They are materials input for DD simulations and are constructed based on the understanding of dislocation motion at the atomistic level.

  4. Craniovertebral realignment for basilar invagination and atlantoaxial dislocation secondary to rheumatoid arthritis

    Goel Atul

    2004-07-01

    Full Text Available Objective: We present our experience of treating nine consecutive cases of rheumatoid arthritis involving the craniovertebral junction by atlantoaxial joint manipulation and attempts towards restoration of craniovertebral region alignments. Material and results: Between November 2001 and March 2004, nine cases of rheumatoid arthritis involving the craniovertebral junction were treated in our department of neurosurgery. Six patients had basilar invagination and 'fixed' atlantoaxial dislocation and three patients had a retroodontoid process pannus and mobile and incompletely reducible atlantoaxial dislocation. The patients ranged from 24 to 74 years in age. Six patients were males and three were females. Neck pain and spastic quadriparesis were the most prominent symptoms. Surgery involved attempts to reduce the atlantoaxial dislocation and basilar invagination by manual distraction of the facets of the atlas and axis. Reduction of the atlantoaxial dislocation and of basilar invagination and stabilization of the region was achieved by placement of bone graft and metal spacers within the joint and direct inter-articular plate and screw method of atlantoaxial fixation. Following surgery all the patients showed symptomatic improvement and restoration of craniovertebral alignments. Follow-up ranged from four to 48 months (average 28 months. Conclusion: Manipulation of the atlantoaxial joints and restoring the anatomical craniovertebral alignments in selected cases of rheumatoid arthritis involving the craniovertebral junction leads to remarkable and sustained clinical recovery.

  5. Risk of dislocation using large- vs. small-diameter femoral heads in total hip arthroplasty

    Plate Johannes F

    2012-10-01

    Full Text Available Abstract Background Dislocation remains a difficult problem in total hip arthroplasty. Large-diameter femoral heads may lower the incidence of dislocation by enhancing the jump distance and decreasing impingement, but their performance against small-diameter heads has not been assessed. This study compared the mid-term radiographic and functional outcomes of two matched cohorts of patients undergoing total hip arthroplasty who had a high pre-operative risk for dislocation and who received either small-diameter (26- or 28-millimeters or large-diameter (≥36-millimeters femoral heads. Methods All patients who received large-diameter heads (≥36-millimeter between 2002 and 2005, and who had pre-operative risk factors for dislocation, were identified in the institution’s joint registry. Forty-one patients (52 hips who received large-diameter heads were identified, and these patients were matched to 48 patients (52 hips in the registry who received small-diameter femoral heads. Results At mean final follow-up of 62 months (range, 49 to 101 months, both groups achieved excellent functional outcomes as measured by Harris Hip scores, with slightly better final scores in the large-diameter group (90 vs. 83 points. No patient showed any radiographic signs of loosening. No patient dislocated in the large-diameter femoral head group; the smaller-diameter group had a greater rate of dislocation (3.8%, 2 out of 52. Conclusions Large-diameter femoral head articulations may reduce dislocation rates in patients who have a high pre-operative risk for dislocation while providing the same functional improvements and safety as small-diameter bearings.

  6. On the measure of dislocation densities from diffraction line profiles: A comparison with discrete dislocation methods

    In this work the accuracy and range of applicability of peak broadening models, from which dislocation densities can be extracted, is studied. For that purpose dislocation microstructures are generated via a discrete dislocation dynamics method and the internal elastic strains within the simulated volume are calculated. Diffraction peaks are generated from the simulations and a whole pattern line profile analysis method based on the Wilkens model is used to quantify the dislocation densities associated with the simulated microstructures. The work is applied to the case of face-centered cubic crystals deforming in coplanar slip. The accuracy of the analytical models is quantified by considering realistic three-dimensional microstructures containing curved dislocations with a specified distribution. The dependence and sensitivity of the analytical models upon dislocation density and long-range order are investigated. It was found that, provided the distribution of dislocations is rather homogeneous, line profile analysis provides fairly accurate predictions of the dislocation density.

  7. A Numeric Study on Chaotic Dislocation Emission

    HonglaiTan; WeiYang

    1996-01-01

    Crack tip atom-string model is devised to study non-linear features of dislocation emission processes under mode II loads.Dynamic analysis shows that the atom motion at the crack tip changes from periodic to chaotic as the stress intensity factor increases.Study on the dislocation emission band reveals the phenomenon of cloud-like drifting of the dislocation core ahead of the crack tip.

  8. Rare Inferior Shoulder Dislocation (Luxatio Erecta)

    Hakan Cift; Salih Soylemez; Murat Demiroglu; Korhan Ozkan; Vahit Emre Ozden; 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...

  9. Coupled dislocation and martensitic phase transformation dynamics

    Barros, Kipton; Acharya, Amit; Lookman, Turab

    2013-03-01

    We present a field theoretic model that couples dislocation dynamics and plasticity with martensitic phase transformation. Dislocations produce long-range stress via incompatibility of the elastic-distortion field. Phase transformations are modeled with a non-convex elastic potential that contains the crystal symmetries of austenite and martensite phases. We discuss the effects of dislocation dynamics on material microstructure produced under extreme conditions.

  10. Hybrid Dislocated Control and General Hybrid Projective Dislocated Synchronization for Memristor Chaotic Oscillator System

    Junwei Sun; Chun Huang; Guangzhao Cui

    2014-01-01

    Some important dynamical properties of the memristor chaotic oscillator system have been studied in the paper. A novel hybrid dislocated control method and a general hybrid projective dislocated synchronization scheme have been realized for memristor chaotic oscillator system. The paper firstly presents hybrid dislocated control method for stabilizing chaos to the unstable equilibrium point. Based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization has been...

  11. Massively-Parallel Dislocation Dynamics Simulations

    Cai, W; Bulatov, V V; Pierce, T G; Hiratani, M; Rhee, M; Bartelt, M; Tang, M

    2003-06-18

    Prediction of the plastic strength of single crystals based on the collective dynamics of dislocations has been a challenge for computational materials science for a number of years. The difficulty lies in the inability of the existing dislocation dynamics (DD) codes to handle a sufficiently large number of dislocation lines, in order to be statistically representative and to reproduce experimentally observed microstructures. A new massively-parallel DD code is developed that is capable of modeling million-dislocation systems by employing thousands of processors. We discuss the general aspects of this code that make such large scale simulations possible, as well as a few initial simulation results.

  12. Anderson localization of light with topological dislocations

    Lobanov, Valery E; Vysloukh, Victor A; Torner, Lluis

    2013-01-01

    We predict Anderson localization of light with nested screw topological dislocations propagating in disordered two-dimensional arrays of hollow waveguides illuminated by vortex beams. The phenomenon manifests itself in the statistical presence of topological dislocations in ensemble-averaged output distributions accompanying standard disorder-induced localization of light spots. Remarkably, screw dislocations are captured by the light spots despite the fast and irregular transverse displacements and topological charge flipping undertaken by the dislocations due to the disorder. The statistical averaged modulus of the output local topological charge depends on the initial vorticity carried by the beam.

  13. Robust atomistic calculation of dislocation line tension

    Szajewski, B. A.; Pavia, F.; Curtin, W. A.

    2015-12-01

    The line tension Γ of a dislocation is an important and fundamental property ubiquitous to continuum scale models of metal plasticity. However, the precise value of Γ in a given material has proven difficult to assess, with literature values encompassing a wide range. Here results from a multiscale simulation and robust analysis of the dislocation line tension, for dislocation bow-out between pinning points, are presented for two widely-used interatomic potentials for Al. A central part of the analysis involves an effective Peierls stress applicable to curved dislocation structures that markedly differs from that of perfectly straight dislocations but is required to describe the bow-out both in loading and unloading. The line tensions for the two interatomic potentials are similar and provide robust numerical values for Al. Most importantly, the atomic results show notable differences with singular anisotropic elastic dislocation theory in that (i) the coefficient of the \\text{ln}(L) scaling with dislocation length L differs and (ii) the ratio of screw to edge line tension is smaller than predicted by anisotropic elasticity. These differences are attributed to local dislocation core interactions that remain beyond the scope of elasticity theory. The many differing literature values for Γ are attributed to various approximations and inaccuracies in previous approaches. The results here indicate that continuum line dislocation models, based on elasticity theory and various core-cut-off assumptions, may be fundamentally unable to reproduce full atomistic results, thus hampering the detailed predictive ability of such continuum models.

  14. Enabling Strain Hardening Simulations with Dislocation Dynamics

    Arsenlis, A; Cai, W

    2006-12-20

    Numerical algorithms for discrete dislocation dynamics simulations are investigated for the purpose of enabling strain hardening simulations of single crystals on massively parallel computers. The algorithms investigated include the /(N) calculation of forces, the equations of motion, time integration, adaptive mesh refinement, the treatment of dislocation core reactions, and the dynamic distribution of work on parallel computers. A simulation integrating all of these algorithmic elements using the Parallel Dislocation Simulator (ParaDiS) code is performed to understand their behavior in concert, and evaluate the overall numerical performance of dislocation dynamics simulations and their ability to accumulate percents of plastic strain.

  15. Dislocation-driven surface dynamics on solids.

    Kodambaka, S; Khare, S V; Swiech, W; Ohmori, K; Petrov, I; Greene, J E

    2004-05-01

    Dislocations are line defects that bound plastically deformed regions in crystalline solids. Dislocations terminating on the surface of materials can strongly influence nanostructural and interfacial stability, mechanical properties, chemical reactions, transport phenomena, and other surface processes. While most theoretical and experimental studies have focused on dislocation motion in bulk solids under applied stress and step formation due to dislocations at surfaces during crystal growth, very little is known about the effects of dislocations on surface dynamics and morphological evolution. Here we investigate the near-equilibrium dynamics of surface-terminated dislocations using low-energy electron microscopy. We observe, in real time, the thermally driven nucleation and shape-preserving growth of spiral steps rotating at constant temperature-dependent angular velocities around cores of dislocations terminating on the (111) surface of TiN in the absence of applied external stress or net mass change. We attribute this phenomenon to point-defect migration from the bulk to the surface along dislocation lines. Our results demonstrate that dislocation-mediated surface roughening can occur even in the absence of deposition or evaporation, and provide fundamental insights into mechanisms controlling nanostructural stability. PMID:15129275

  16. Interactions between dislocations and point defects

    Copper and copper-aluminum alloys were irradiated using a 3MV EM, and the interactions between straight dislocations and point defects were studied. Edge-dislocations climb up during irradiation and the interstitial-type loops are not formed around them. On the other hand, screw-dislocations turn into the helical ones by absorbing interstitials induced by irradiation. During irradiation, the number of helical turns do not change but the radius of helix increases. At the same time, the interstitial-type dislocation loops are formed close by the helical dislocations. The growth rate of these loops is the same as that of the radius of helical dislocations. From these facts, the sink efficiency of dislocations for point defects can be determined. Furthermore, when the fresh screw-dislocations are introduced by in-situ deformation during irradiation, the interstitial-type loops are preferentially formed on the active slip planes. The enhanced nucleation of the loops is closely related to the point defects formed by the motion of dislocation-jogs

  17. Moving dislocations studied by nuclear magnetic resonance

    Movements of dislocations in alkalihalogenides under strain conditions have been investigated by NMR techniques. From theory, it follows that electric quadrupole interactions contribute much more to dislocation motion than tripole interactions. Under the experimental conditions, the actual movement takes place in a time much shorter than 10-8 sec, and the period between successive jumps lasts much longer than 10-4 sec. The distance between the dislocations is found to vary from 5.10-4 cm to 5.10-5 in a deformation test. The mean distance covered by a moving dislocation agrees well with this distance

  18. Multiscale modeling of dislocation-precipitate interactions in Fe: From molecular dynamics to discrete dislocations

    Lehtinen, Arttu; Granberg, Fredric; Laurson, Lasse; Nordlund, Kai; Alava, Mikko J.

    2016-01-01

    The stress-driven motion of dislocations in crystalline solids, and thus the ensuing plastic deformation process, is greatly influenced by the presence or absence of various pointlike defects such as precipitates or solute atoms. These defects act as obstacles for dislocation motion and hence affect the mechanical properties of the material. Here we combine molecular dynamics studies with three-dimensional discrete dislocation dynamics simulations in order to model the interaction between different kinds of precipitates and a 1/2 {110 } edge dislocation in BCC iron. We have implemented immobile spherical precipitates into the ParaDis discrete dislocation dynamics code, with the dislocations interacting with the precipitates via a Gaussian potential, generating a normal force acting on the dislocation segments. The parameters used in the discrete dislocation dynamics simulations for the precipitate potential, the dislocation mobility, shear modulus, and dislocation core energy are obtained from molecular dynamics simulations. We compare the critical stresses needed to unpin the dislocation from the precipitate in molecular dynamics and discrete dislocation dynamics simulations in order to fit the two methods together and discuss the variety of the relevant pinning and depinning mechanisms.

  19. Internal derangement of the temporomandibular joint

    Internal Derangement is one of the most common disorders of the Temporomandibular joint. It is defined as an abnormal anatomical relationship between the discus articularis and the other structures of the temporomandibular joint. More than 2/3 of patients with clinical symptoms of the temporomandibular joint have an internal derangement. The most frequent finding in internal derangement is an anterior dislocation of the disc with reduction after mouth opening. In more severe cases a complete anterior dislocation is found without reduction of the disc. Internal derangement is a risk factor for developing osteoarthritis with remodeling of the condylus and the fossa mandibularis. The most important modalities of radiologic diagnosis are arthrography, CT and MRI. The diagnosis of craniofacial dysfunction has been improved dramatically by modern imaging techniques, which have become essential tools for primary diagnostic and evaluation after conservative or surgical therapy. MRI has become the gold standard. (orig.)

  20. Proximal tibiofibular joint: Rendezvous with a forgotten articulation

    Amitav Sarma; Bhaskar Borgohain; Bishwajeet Saikia

    2015-01-01

    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, espe...

  1. Soft Tissue Aspects of the Shoulder Joint

    Khoschnau, Shwan

    2012-01-01

    The aim of this thesis was to study different aspects of the soft tissues of the shoulder joint. The variation in the quality of the tendons and ligaments can be explained by genetic factors. To test the hypothesis that collagen 1 α1 Sp1 polymorphism is related to the occurrence of cruciate ligament ruptures and shoulder dislocations, a total of 358 patients (233 patients with cruciate ligament ruptures and 126 with shoulder dislocations) were included in the study. We found a decreased risk ...

  2. Atomistic simulation of hydrogen dynamics near dislocations in vanadium hydrides

    Ogawa, Hiroshi, E-mail: h.ogawa@aist.go.jp

    2015-10-05

    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.

  3. Atomistic simulation of hydrogen dynamics near dislocations in vanadium hydrides

    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

  4. "Dislocation"

    Li Wei

    2006-01-01

    @@ Over the past five years since September 11, the international community has been highly focused on the increasingly serious terrorist threat. In order to strike the international terrorist force, with al Qaeda as its core, the United Nations Security Council has established a special counter-terrorism committee, drawing up 12 related resolutions, agreements and conventions; multilateral and bilateral counter-terrorism cooperation has been expanding and deepening unceasingly. Many countries have brought counter-terrorism into their national security strategy, established or revised relevant laws, increased the input of manpower, material resources, and funds, actively researched and developed new technology and strengthened all kinds of counter-terrorist measures. Theoretically, international society has created an "inescapable net" for terrorism.

  5. Denervation of the wrist joint.

    Buck-Gramcko, D

    1977-01-01

    A collective review was made of the results of denervation of the wrist joint for painful restrictiorn of motion done in 313 patients and follow-up studies on 195 (average 4.1 years, ranging from 9 months to 14 years). Complete denervation was done in only 30, partial denervation in the others being done after testing with local anesthetic blocks. Sixty-nine of the patients retained a moble wrist without pain or with slight pain with heavy work. No evidence of Charcot-like joints was seen. Poorest results followed when the operation was done for sequelae of intra-articular fracture of the radius, fracture dislocations, unstable ligamentous support, joint surface destruction, or for those required to do heavy manual labor. Arthrodesis was done secondarily in nine patients. PMID:839055

  6. Dislocated interests and climate change

    Davis, Steven J.; Diffenbaugh, Noah

    2016-06-01

    The predicted effects of climate change on surface temperatures are now emergent and quantifiable. The recent letter by Hansen and Sato (2016 Environ. Res. Lett. 11 034009) adds to a growing number of studies showing that warming over the past four decades has shifted the distribution of temperatures higher almost everywhere, with the largest relative effects on summer temperatures in developing regions such as Africa, South America, southeast Asia, and the Middle East (e.g., Diffenbaugh and Scherer 2011 Clim. Change 107 615–24 Anderson 2011 Clim. Change 108 581; Mahlstein et al 2012 Geophys. Res. Lett. 39 L21711). Hansen and Sato emphasize that although these regions are warming disproportionately, their role in causing climate change—measured by cumulative historical CO2 emissions produced—is small compared to the US and Europe, where the relative change in temperatures has been less. This spatial and temporal mismatch of climate change impacts and the burning of fossil fuels is a critical dislocation of interests that, as the authors note, has ‘substantial implications for global energy and climate policies.’ Here, we place Hansen and Sato’s ‘national responsibilities’ into a broader conceptual framework of problematically dislocated interests, and briefly discuss the related challenges for global climate mitigation efforts.

  7. Evaluation of mobile dislocation density based on distribution function of dislocation segments

    周志敏; 孙艳蕊; 周海涛

    2004-01-01

    A function is offered to represent the distribution of reduced length of dislocation segments. The segment distribution of materials, e. g. , MgO and Cu, can be well described by taking appropriate values of parametersm and n. Based on this function, a model for evaluating the mobile dislocation density is developed. Provided the total dislocation density and applied stress are known, the mobile dislocation density could be readily assessed by using this model. For pure copper the mobile dislocation density and strain rates at deferent strains are evaluated. The calculated results are consistent with the known experimental data.

  8. Dislocation-Free Czochralski Silicon Crystal Growth without the Dislocation-Elimination-Necking Process

    Hoshikawa, Keigo; Huang, Xinming; Taishi, Toshinori; Kajigaya, Tomio; Iino, Takayuki

    1999-12-01

    Dislocation-free silicon crystals have been grown successfully from heavily-boron-doped silicon melts by the Czochralski method without the dislocation-elimination-necking process (Dash neck). A dislocation-free silicon seed of orientation with a boron concentration of about 4×1019 atoms/cm3 was used to grow a silicon crystal with the same boron concentration. No dislocation was generated in the seed during the dipping process, and no misfit dislocation occurred in the grown crystal. These results show that shoulder and body growth can be started immediately after the seeding process.

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

    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.

  10. Interactions between Dislocations and Grain Boundaries

    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

  11. Dislocation networks in phosphorus-implanted silicon

    Observations, by transmission electron microscopy have been made on defects generated in 50 keV, high-dose (1 x 1015 to 3 x 1016 ions/cm2) phosphorus-implanted silicon (111) wafers followed by 11000C isothermal annealing in inert (dry N2) and oxidizing (wet O2) atmospheres. The formation of dislocation networks is closely associated with the generation of interstitial type dislocation loops which grow from point defects produced by ion implantation in silicon wafers. Also, dislocations grow more easily in wet O2 annealing than in dry N2. In wet O2 annealing, dislocation networks are formed by annealing within 1-2 min for samples implanted with doses above 3 x 1015 ions/cm2, and they move to deeper depths in the wafers during annealing. On the other hand, in dry N2 annealing, the critical ion dose for generation of dislocation networks is 1 x 1016 ions/cm2 and the location of dislocation networks in the wafers is usually unchanged during annealing. Such a difference in the generation and motion of dislocations between the two atmospheres can be explained in terms of the analysis of Sanders and Dobson (1969) for the vacancy flow between defect and surface. It is also shown that by implanting silicon into phosphorus-diffused layers, the generation of dislocation networks is strongly correlated with the formation of secondary defects caused by implantation and annealing. (author)

  12. Simulations of dislocation dynamics in aluminum interconnects

    Nicola, L; Van der Giessen, E; Needleman, A; Zavaliangos, A; Tikare,; Olevsky, EA

    2002-01-01

    A discrete dislocation simulation of plastic deformation in metallic interconnects caused by thermal stress is carried out. The calculations are carried out using a two dimensional plane strain formulation with only edge dislocations. A boundary value problem is formulated and solved for the evoluti

  13. The neuropathic joint.

    Sequeira, W

    1994-01-01

    Neuropathic arthritis is a destructive arthropathy frequently associated with loss of proprioception. A third of patients, however, may have no demonstrable neurological deficit. Patients with diabetes, syphilis, syringomyelia and other neuropathies are particularly prone to developing this joint disease. The diagnosis of Charcot's joints should be considered in anyone who develops what appears to be a severe osteoarthritis or a transverse fracture of the tibia or fibula after minor trauma. Scoliosis with particularly destructive changes on radiography should prompt a search for syringomyelia or syphilis. The most common radiographic abnormalities are those of distension in 3D (Dislocation, Destruction and Degeneration). An atrophic form with resorption of the proximal humerus, most frequently described in syringomyelia, has been observed in diabetes. Loss of the distal end of the clavicle has not been described before in the neuropathies. These changes coupled with speckled calcification or shards of bone in the periarticular soft tissue confirm the diagnosis. Infection and CPPD crystal disease can be difficult to exclude. The joint fluid may be inflammatory and infection may be a complication. Treatment includes anti-inflammatories and splinting. Indications for surgery are limited. PMID:8070170

  14. A nonsingular solution of the edge dislocation in the gauge theory of dislocations

    A (linear) nonsingular solution for the edge dislocation in the translational gauge theory of defects is presented. The stress function method is used and a modified stress function is obtained. All field quantities are globally defined and the solution agrees with the classical solution for the edge dislocation in the far field. The components of the stress, strain, distortion and displacement fields are also defined in the dislocation core region and they have no singularity there. The dislocation density, moment and couple stress for an edge dislocation are calculated. The solutions for the stress and strain fields obtained here are in agreement with those obtained by Gutkin and Aifantis through an analysis of the edge dislocation in the strain gradient elasticity. Additionally, the relation between the gauge theory and Eringen's so-called nonlocal theory of dislocations is given

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

    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. Joint ventures

    Sørensen, Karsten Engsig

    Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret......Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret...

  17. Joint Disorders

    A joint is where two or more bones come together, like the knee, hip, elbow, or shoulder. Joints can be damaged by many types of injuries or diseases, including Arthritis - inflammation of a joint. It causes pain, stiffness, and swelling. Over time, ...

  18. Coracoclavicular joint

    The coracoclvicular joint, a rear abnormality which may be the cause of pain in the shoulder and limitation of motion of the shoulder joint, is discussed. A case of coracoclvicular joint with shoulder pain was observed in 65 yrs old Korean male

  19. TRAUMATIC HIP DISLOCATION IN CHILDREN YOUNGER THAN 3 YEARS : A SERIES OF 3 CASES

    Navin

    2015-03-01

    Full Text Available The musculoskeletal anatomy of children is qui te different from that of adults. The capsule, periosteum and other soft tissues surrounding the joints is very pliable and dislocations can occur even following trivial injuries . However dislocation occurring in a child population is a rare entity. There are a few case reports of hip dislocations in children < 3 years. We present here a series of 3 cases of paediatric hip dislocations which presented to us for management. The age of the children were between 24 - 27 months. Incidentally all 3 patients were b oys and all 3 were right sided dislocations. None of them had any associated fractures. Two of them had a fall from height and one child fell off a slide. All 3 patients presented within 5 hours following injury. Closed reduction under anaesthesia was perf ormed and post reduction the children were immobilized in a broom - stick plaster for 6 weeks. All children were followed up with serial x - rays and a MRI done immediately following reduction then at 6 and 18 months. There was no evidence of chondrolysis or a vascular necrosis in any of the children at the last follow - up. They all had full range of movements with no limitation of function. We conclude that with early recognition and early reduction of the hip within the golden period (6 hours the occurrence of complications can be prevented.

  20. A new autoreduction method for anterior shoulder dislocation: the GONAIS method.

    Gonai, Shiro; Kamio, Yoshito; Matsuoka, Tomoyuki; Harunari, Manabu; Saito, Yutaka; Takuma, Kiyotsugu

    2016-01-01

    Although techniques for autoreduction of anterior shoulder dislocation have been developed, no reports have detailed an autoreduction method using the zero position and traction on the affected arm. Therefore, we developed a new autoreduction technique using the zero position and gentle autotraction. The objective of this study is to present our experience with a new method for autoreduction of anterior shoulder dislocation called the GONAIS (a backronym for “Grasp a waist-high object, Opposite arm assists, Nonsedated, Autoreduction/autotraction, Immobilize the grasped object, and Squatting and stooping”) method. A 41-year-old healthy woman with a history of left shoulder dislocation presented to the emergency department with left shoulder pain while attaching her seatbelt. The X-ray examination revealed subcoracoid dislocation of the left shoulder. The patient tried the GONAIS method after simple guidance and demonstration. Although she felt pain once when weakening traction, she achieved autoreduction successfully in only 2 min and 50 s. Clinical examination after autoreduction revealed normal neurovascular findings and appearance of the shoulder. The X-ray revealed glenohumeral joint reduction and no fracture. Here, our patient using the GONAIS method achieved shoulder autoreduction in a short time. The GONAIS method does not require lying down or sitting on the ground, does not necessarily require the opposite arm, and is minimally invasive. This method would likely be helpful for those who cannot quickly reach a hospital for treatment of anterior shoulder dislocation. PMID:26168697

  1. Diffusion along and around dislocations

    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: ∂C/∂t=D[∂2C/∂r2+1/r∂C/∂ r + ∂2C/∂z2] 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/(a2D'); 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 √(D/(a2D')) 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)

  2. Tratamento da luxação paralítica do quadril na paralisia cerebral tetraparética espástica com osteotomia do fêmur e do ilíaco sem abertura da cápsula articular (capsuloplastia Hip dislocation treatment in cerebral palsy patients with spastic quadriplegia with femoral and pelvic osteotomies, without opening of the joint capsule (capsuloplasty

    Fernando Farcetta Junior

    2010-01-01

    Full Text Available OBJETIVO: Mostrar o planejamento pré-operatório, e os resultados do tratamento cirúrgico da luxação paralítica do quadril em pacientes com paralisia cerebral. A técnica utilizada foi a osteotomia derrotatória e varizante do fêmur proximal, associada à osteotomia do ilíaco tipo Dega, sem abertura da cápsula articular. MÉTODOS: Realizamos um estudo retrospectivo de 10 quadris em oito pacientes com paralisia cerebral tipo tetraparesia espástico, submetidos a tratamento cirúrgico entre 2003 e 2005 com a mesma técnica cirúrgica. Foram avaliados parâmetros clínicos e radiográficos pré e pós-operatórios, bem como o planejamento pré-operatório com uso do intensificador de imagem. Os parâmetros clínicos analisados foram: dor, dificuldade de higiene e dificuldade de posicionamento. Os parâmetros radiológicos foram os índices de Reimers, índice acetabular e ângulo cervicodiafisário. Estes resultados foram submetidos a análise estatística. RESULTADOS: Obtivemos bons resultados com esta técnica. Com um seguimento médio de três anos, todos os quadris estavam reduzidos na última consulta, com alto grau de satisfação dos familiares, em relação ao tratamento. Além disso, mostramos que o planejamento pré-operatório com uso do intensificador de imagem nos permite a redução e estabilização desses quadris sem a necessidade de capsuloplastia. CONCLUSÃO: Os autores concluíram que no tratamento da luxação do quadril dos pacientes com paralisia cerebral tetraparéticos espásticos com o planejamento pré-operatório, não é necessária a capsuloplastia para estabilização da articulação coxofemoral.OBJECTIVES: To show the preoperative planning and the results of surgical treatment for paralytic hip dislocation in children with cerebral palsy. The techniques used were proximal femoral varus derotation osteotomy and Dega osteotomy without opening of the joint capsule. METHODS: We performed a retrospective review of

  3. Evolution, Interaction, and Intrinsic Properties of Dislocations in Intermetallics: Anisotropic 3D Dislocation Dynamics Approach

    Qian Chen

    2008-08-18

    The generation, motion, and interaction of dislocations play key roles during the plastic deformation process of crystalline solids. 3D Dislocation Dynamics has been employed as a mesoscale simulation algorithm to investigate the collective and cooperative behavior of dislocations. Most current research on 3D Dislocation Dynamics is based on the solutions available in the framework of classical isotropic elasticity. However, due to some degree of elastic anisotropy in almost all crystalline solids, it is very necessary to extend 3D Dislocation Dynamics into anisotropic elasticity. In this study, first, the details of efficient and accurate incorporation of the fully anisotropic elasticity into 3D discrete Dislocation Dynamics by numerically evaluating the derivatives of Green's functions are described. Then the intrinsic properties of perfect dislocations, including their stability, their core properties and disassociation characteristics, in newly discovered rare earth-based intermetallics and in conventional intermetallics are investigated, within the framework of fully anisotropic elasticity supplemented with the atomistic information obtained from the ab initio calculations. Moreover, the evolution and interaction of dislocations in these intermetallics as well as the role of solute segregation are presented by utilizing fully anisotropic 3D dislocation dynamics. The results from this work clearly indicate the role and the importance of elastic anisotropy on the evolution of dislocation microstructures, the overall ductility and the hardening behavior in these systems.

  4. Dislocation dynamics based modelling of dislocation-precipitate interactions in bcc metals

    The influence of dislocation core on the interaction between an edge dislocation and a spherical precipitate was investigated using the combination of the parametric dislocation dynamics and the boundary element method with a dislocation core model. In the results of the simulations, the dislocation core of the edge dislocation behaves differently between inside and outside the precipitate. The calculated critical resolved shear stress is strongly affected by the dislocation core. Therefore, it could be found that the influence of dislocation core is a dominant factor in determining the strength of the interaction. Then, we derived an equation for evaluating the influence of dislocation core on the critical resolved shear stress. The derivation was done using the difference between the γ-surface energy in iron and that in copper, because there is a significant difference in-between. The equation can be solved without any simulation runs. The result of the equation was then compared to that of the simulations, which showed that the equation gives a good evaluation of the influence of dislocation core. Since the equation is derived without any limitation on the kind of materials, it can be applicable to the evaluation of the strength of the other alloys with precipitates.

  5. Continuum framework for dislocation structure, energy and dynamics of dislocation arrays and low angle grain boundaries

    Zhu, Xiaohong; Xiang, Yang

    2014-09-01

    We present a continuum framework for dislocation structure, energy and dynamics of dislocation arrays and low angle grain boundaries that are allowed to be nonplanar or nonequilibrium. In our continuum framework, we define a dislocation density potential function on the dislocation array surface or grain boundary to describe the orientation dependent continuous distribution of dislocations in a very simple and accurate way. The continuum formulations incorporate both the long-range dislocation interaction and the local dislocation line energy, and are derived from the discrete dislocation model. The continuum framework recovers the classical Read-Shockley energy formula when the long-range elastic fields of the low angle grain boundaries are canceled out. Applications of our continuum framework in this paper are focused on dislocation structures on static planar and nonplanar low angle grain boundaries and misfitting interfaces. We present two methods under our continuum framework for this purpose, including the method based on the Franks formula and the energy minimization method. We show that for any (planar or nonplanar) low angle grain boundary, the Franks formula holds if and only if the long-range stress field in the continuum model is canceled out, and it does not necessarily hold for a total energy minimum dislocation structure.

  6. New Criterion for Evaluating the Peak Shear Strength of Rock Joints Under Different Contact States

    Tang, Zhi Cheng; Wong, Louis Ngai Yuen

    2016-04-01

    In practice, the peak shear strength of rock joints is not dictated only by the surface roughness, but also the degree of matching between the joint surfaces. The latter is due to alteration/dislocation caused by external factors, such as the vibration due to nearby blasting, excavation or earthquake. In the present study, the peak shear strengths of rock joints under different contact states are investigated by direct shear test using artificial rock joints. The rock joints under different contact states are modeled by imposing varying magnitude of horizontal dislocation along the shear direction between the upper and lower rock blocks. The peak shear strength was found to decrease with increasing dislocation. A new empirical shear strength criterion is put forward to capture the peak shear strength of un-matching rock joints as an extension of a previously published peak shear strength criterion for matching rock joints by the first author and his co-workers. In the present proposed criterion, a new joint contact state coefficient, which is a function of the normalized dislocation and the quantified three-dimensional roughness metric of joint surface, is proposed. The good agreement between calculated values and test results indicates that the proposed criterion is capable of estimating the peak shear strength of rock joints under different contact states. The proposed criterion is expressed in a quantitative way and the required parameters can be easily determined in the laboratory.

  7. Magnetic resonance imaging evaluation of capsulolabral tears after traumatic primary anterior shoulder dislocation. A prospective comparison with arthroscopy of 25 cases

    Suder, P.A.; Frich, Lars Henrik; Hougaard, K.;

    1995-01-01

    The purpose of our study was to evaluate the use of static magnetic resonance imaging (MRI) as a preoperative diagnostic tool in young patients with a traumatic primary anterior shoulder dislocation. Twenty-five patients who had acute primary traumatic anterior shoulder dislocation were examined...... with MRI and arthroscopy. The patients (18 male and 7 female) were between 16 and 39 years old (mean age, 27 years). They had no previous shoulder dislocations. The dislocations were confirmed radiographically. Examination with MRI and arthroscopy was performed within 10 days after the trauma. The MRI...... joint side rotator cuff tear, 1 partial rupture of the biceps tendon, and 1 osseous Bankart lesion. Anterior capsulolabral tears and Hill-Sachs lesions appeared with a high incidence after acute anterior primary shoulder dislocation. Conventional MRI was only moderately reliable in the preoperative...

  8. Ultrasonic Study of Dislocation Dynamics in Lithium -

    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.

  9. [Preliminary treatment of congenital hip dislocation using physical therapy based on neurophysiology].

    Niethard, F U

    1987-01-01

    Adductor tightness is a typical symptom in CDH. In cases of subluxation and complete dislocation even a rigid abduction contracture can occur, preventing reduction and favouring redislocation. The contracture of the hip joint is the result of neurophysiological disorders, which can be treated by an exercise program on a neurophysiological basis. 62 children with 73 severely contracted and 5 hypotonic hip dislocations have been treated by the so-called "Vojta-program" before reduction. In a prospective study over 5 years this kind of treatment has been very successful: the incidence of necrosis of the femoral head could be reduced to 4%, long-lasting traction was not necessary anymore and the rigid hip joints required open reduction only in 2 cases. PMID:3577341

  10. Transition joint

    A transition joint is disclosed for joining together tubular pieces formed respectively from a low alloy or carbon steel and a high temperature alloy composition having substantially different characteristics such as coefficient of thermal expansion, the transition joint including a plurality of tubular parts interconnected with each other by means of friction weld joints formed at an angle of 900 to the axis of the transition joint, the tubular parts at opposite ends of the transition joint being selected to facilitate in situ welding to the low alloy or carbon steel and high temperature alloy respectively. This friction welded transition joint can be used whenever different tubular pieces need to be joined together so that the joint can withstand high temperatures, for instance in heat exchangers and the such like. (Auth.)

  11. Treatment of cervical dislocation with locked facets

    YU Ze-sheng; James J.Yue; WEI Feng; LIU Zhong-jun; CHEN Zhong-qiang; DANG Geng-ting

    2007-01-01

    Background Lower cervical dislocation with locked facets is common in cervical injury. The locked facets include unilateral and bilateral types. Different successful closed reduction rates has been achieved between unilateral and bilateral types by using rapid skull traction, which was commonly used to reduce the cervical dislocation. It is important to investigate a suitable management specific to patients with different types of cervical locked facets.Methods A total of 38 patients with cervical dislocation with locked facet due to cervical injury treated by rapid skull traction and operation from 1988 to 2005 were reviewed. Rapid skull traction was used in all the patients. Successful closed reduction rate was 88.0% in patients with bilateral cervical locked facets and that was 15.4% in those with unilateral cervical locked facets. These data were then statistically compared by Chi-square test. Patients who were reduced successfully underwent anterior cervical discectomy and fusion at the injured level, and those who failed in closed reduction received posterior open reduction and fixation.Results In this series, there was statistically significant difference (P<0.05) in the rate of successful closed skull traction reduction between unilateral and bilateral locked facets dislocation. Unilateral cervical locked facets dislocation was not easily reduced by skull traction which was suitable for reduction of bilateral cervical locked facets dislocation. However,unilateral cervical locked facets dislocation can be reduced by posterior open reduction.Conclusions Unilateral cervical locked facets dislocation should be treated immediately with posterior open reduction and instrumentation. Bilateral cervical locked facets dislocation can be reduced by rapid skull traction firstly and anterior cervical discectomy and interbody fusion later.

  12. Knee Dislocation in the Morbidly Obese Patient.

    Carr, James Bradley; Werner, Brian Christopher; Miller, Mark D; Gwathmey, Frank Winston

    2016-05-01

    Though a relatively rare orthopedic injury, knee dislocation in the morbidly obese population has been increasingly reported in the literature. These injuries are often referred to as "ultralow-velocity knee dislocations" since they commonly occur after a seemingly trivial injury, such as a ground level fall. As a result, these injuries are often underappreciated and initially misdiagnosed. Even though these injuries are low-velocity, they should still be regarded as a high energy injury because of the large amount of mass contributing to the dislocating force. Knee dislocations in the morbidly obese are associated with a particularly high rate of neurovascular injury. A timely and accurate diagnosis is crucial to avoid serious limb-threatening complications, including the need for amputation. Therefore, evaluating physicians should maintain a high suspicion for a knee dislocation in any morbidly obese patient who presents with knee pain following a seemingly innocuous injury. Management of these injuries is controversial. Associated vascular injuries must be identified promptly and appropriately managed by a vascular surgery team. There is no consensus on the ideal orthopedic treatment of knee dislocations in the morbidly obese patient. Operative treatment can be fraught with complications, including a higher rate of neurovascular injury, increased surgical complications, and poor subjective patient outcome scores compared with nonobese patients sustaining a high-velocity knee dislocation. It is paramount that treating physicians are familiar with the unique challenges of treating knee dislocations in the morbidly obese patient when discussing risks and benefits of treatment options. This article presents a review of the existing literature on knee dislocations in the morbidly obese population, including diagnosis, management, and outcomes. PMID:26838970

  13. Dislocations in SmS single crystals

    Single crystals of SmS with NaCl structure are grown by zone melting in a sealed molybdenum tube. Dislocations introduced during cleaving the crystal are investigated by transmission electron microscopy. The dislocations have Burgers vector of 1/2 and their glide plane is (11-bar0), i.e. the slip system is (11-bar0) as in alkali-halide NaCl-type crystals. The slip seems to be governed by the Peierls mechanism for the screw dislocation. (author)

  14. MODERN DIAGNOSTIC AND TREATMENT PRINCIPLES OF LISFRANC MIDFOOT DISLOCATIONS IN ATHLETES

    Răzvan BANDAC

    2012-01-01

    Lisfranc midfoot dislocations include bone and ligament injuries to the tarsometatarsal joint complex. Rarelesion, with an incidence rate of 1 to 55,000 patients annually, 20% of injuries remain undiagnosed. Mechanisms ofinjury are direct and indirect, including traffic accidents and sports. Clinical signs and symptoms are: midfoot pain,inability to bear weight, leg deformity and swelling, and plantar ecchymosis. Pedal artery or deep peroneal nerve maybe compromised and the compartment syndro...

  15. Post traumatic subconjunctival dislocation of lens in Ehlers-Danlos syndrome.

    Sharma Yograj

    2003-01-01

    Full Text Available Ehlers-Danlos Syndromes are a rare group of inherited connective tissue disorders of defective collagen synthesis. They predominantly involve the skin, joints and vessels. Ocular involvement in the form of blue sclera, microcornea and susceptibility to trauma is a common feature of EDS type VI. A minor ocular trauma in these patients can cause globe rupture. We herein report simple and successful management of a case of traumatic subconjunctival dislocation of lens in a patient of EDS type VI.

  16. Unusual presentation of Lisfranc fracture dislocation associated with high-velocity sledding injury: a case report and review of the literature

    Benejam Christopher E; Potaczek Steven G

    2008-01-01

    Abstract Introduction Lisfranc fracture dislocations of the foot are rare injuries. A recent literature search revealed no reported cases of injury to the tarsometatarsal (Lisfranc) joint associated with sledding. Case presentation A 19-year-old male college student presented to the emergency department with a Lisfranc fracture dislocation of the foot as a result of a high-velocity sledding injury. The patient underwent an immediate open reduction and internal fixation. Conclusion Lisfranc in...

  17. On dislocation-defect interactions and patterning: stochastic discrete dislocation dynamics (SDD)

    Hiratani, M.; Zbib, H.M. E-mail: zbib@wsu.edu

    2003-12-01

    The problem of dislocation patterning and interaction of threading dislocations with immobile dislocation loops and defects is investigated analytically and computationally based on a statistical analysis and a recently developed model of discrete stochastic dislocation dynamics (SDD), respectively. The statistical analysis is based on the Friedel-Kocks model and shows the validity of the Friedel relation for the critical resolved stress while a power law with different stress dependence is obtained for the average pinning distance on a stable dislocation array. The difference of the stress dependence is attributed to each model assumptions, such as stable dislocation configurations in athermal system or meta-stable configurations in thermally activated system. The SDD computational study includes thermal and strain fluctuation, predicting non-trivial fractal instability of the plastic strain. The height difference correlations of the plastic strain show that the external load causes a multifractality, and enhances the instability at higher order moments.

  18. A nonsingular solution of the edge dislocation in the gauge theory of dislocations

    Lazar, Markus

    2002-01-01

    A (linear) nonsingular solution for the edge dislocation in the translational gauge theory of defects is presented. The stress function method is used and a modified stress function is obtained. All field quantities are globally defined and the solution agrees with the classical solution for the edge dislocation in the far field. The components of the stress, strain, distortion and displacement field are also defined in the dislocation core region and they have no singularity there. The dislo...

  19. Increasing preoperative dislocations and total time of dislocation affect surgical management of anterior shoulder instability

    Denard, Patrick J.; Xuesong Dai; Burkhart, Stephen S.

    2015-01-01

    Purpose: Our purpose was to determine the relationship between number of preoperative shoulder dislocations and total dislocation time and the need to perform bone deficiency procedures at the time of primary anterior instability surgery. Our hypothesis was that need for bone deficiency procedures would increase with the total number and hours of dislocation. Materials and Methods: A retrospective review was performed of primary instability surgeries performed by a single surgeon. Patient...

  20. Dislocation dynamics simulations with climb: kinetics of dislocation loop coarsening controlled by bulk diffusion

    Dislocation climb mobilities, assuming vacancy bulk diffusion, are derived and implemented in dislocation dynamics simulations to study the coarsening of vacancy prismatic loops in fcc metals. When loops cannot glide, comparison of the simulations with a coarsening model based on the line tension approximation shows good agreement. Dislocation dynamics simulations with both glide and climb are then performed. Allowing for glide of the loops along their prismatic cylinders leads to faster coarsening kinetics, as direct coalescence of the loops is now possible. (authors)

  1. 21 CFR 888.3640 - Shoulder joint metal/metal or metal/polymer constrained cemented prosthesis.

    2010-04-01

    ... intended to be implanted to replace a shoulder joint. The device prevents dislocation in more than one... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Shoulder joint metal/metal or metal/polymer... § 888.3640 Shoulder joint metal/metal or metal/polymer constrained cemented prosthesis....

  2. Total hip arthroplasty in paralytic dislocation from poliomyelitis.

    Laguna, Rafael; Barrientos, Jesús

    2008-02-01

    This article presents a case of a patient with degenerative hip disease in paralytic dislocation by poliomyelitis. Poliomyelitis is an acute infection disease caused by a group of neurotrophic viruses, which has a special affinity by the anterior horns cells of the spinal cord and for certain motor nuclei of the brain stem. Paralysis is a flaccid type and characteristically paralysis is asymmetrical. It is said that the joints of the affected limb by poliomyelitis are protected from the development of osteoarthritis. Hip dislocation in poliomyelitis is an acquired deformity caused by flaccid paralysis and the resulting muscular imbalance. In young children, when the gluteus maximus and medius muscles are paralyzed and the hip flexors and adductors are of normal strength, eventual luxation of the hip is almost inevitable. Hip osteoarthritis in a limb with poliomyelitis is an unusual entity because these limbs do not support excessive loads. In patients who present with the residual effects of poliomyelitis including degenerative disease and hip dysplastic, surgery is one of the most difficult challenges faced by reconstructive surgeons. In such cases, surgeons should attempt to optimize the component position and choice, surgical approach, and soft tissue tensioning because stability of the prosthesis can be problematic. PMID:19292189

  3. Double-contrast computed tomographic examination techniques in habitual and recurrent shoulder dislocation

    Preoperative planning of recurrent shoulder dislocation requires an accurate knowledge of bone and soft tissue lesions affecting the joint. A new method of double-contrast CT examination is presented which allows an accurate evaluation of the soft tissue structures important for the stability of the joint. Forty-two patients were examined with this technique, twenty-seven of whom (28 shoulders) were operated on, the procedure being selected on the basis of the CT findings. In all cases the preoperative CT findings corresponded to the intraoperative findings. (orig.)

  4. Dislocation dynamics simulations of interactions between gliding dislocations and radiation induced prismatic loops in zirconium

    The mechanical behavior of Pressurized Water Reactor fuel cladding tubes made of zirconium alloys is strongly affected by neutron irradiation due to the high density of radiation induced dislocation loops. In order to investigate the interaction mechanisms between gliding dislocations and loops in zirconium, a new nodal dislocation dynamics code, adapted to Hexagonal Close Packed metals, has been used. Various configurations have been systematically computed considering different glide planes, basal or prismatic, and different characters, edge or screw, for gliding dislocations with 〈a〉-type Burgers vectors. Simulations show various interaction mechanisms such as (i) absorption of a loop on an edge dislocation leading to the formation of a double super-jog, (ii) creation of a helical turn, on a screw dislocation, that acts as a strong pinning point or (iii) sweeping of a loop by a gliding dislocation. It is shown that the clearing of loops is more favorable when the dislocation glides in the basal plane than in the prismatic plane explaining the easy dislocation channeling in the basal plane observed after neutron irradiation by transmission electron microscopy

  5. Short-range dislocation interactions using molecular dynamics: Annihilation of screw dislocations

    We present results of a large-scale atomistic study of the annihilation of oppositely signed screw dislocations in an fcc metal using molecular dynamics (MD) and an Embedded-Atom-Method (EAM) potential for Cu. The mechanisms of the annihilation process are studied in detail. From the simulation results, we determined the interaction energy between the dislocations as a function of separation. These results are compared with predictions from linear elasticity to examine the onset of non-linear-elastic interactions. The applicability of heuristic models for annihilation of dislocations in large-scale dislocation dynamics simulations is discussed in the light of these results. copyright 1998 Materials Research Society

  6. Dislocation dynamics simulations of interactions between gliding dislocations and radiation induced prismatic loops in zirconium

    Drouet, Julie, E-mail: julie.drouet@cea.fr [Service de Recherches Métallurgiques Appliquées, CEA-Saclay, 91191 Gif-sur-Yvette (France); Dupuy, Laurent; Onimus, Fabien [Service de Recherches Métallurgiques Appliquées, CEA-Saclay, 91191 Gif-sur-Yvette (France); Mompiou, Frédéric [CEMES-CNRS and Université de Toulouse, 29 Rue Jeanne Marvig, 31055 Toulouse Cedex 4 (France); Perusin, Simon [AREVA NP SAS Fuel Business Unit 10, Rue Juliette Recamier, 69456 Lyon Cedex 06 (France); Ambard, Antoine [EDF/R and D Les Renardières, Ecuelles, 77818 Moret sur Loing Cedex (France)

    2014-06-01

    The mechanical behavior of Pressurized Water Reactor fuel cladding tubes made of zirconium alloys is strongly affected by neutron irradiation due to the high density of radiation induced dislocation loops. In order to investigate the interaction mechanisms between gliding dislocations and loops in zirconium, a new nodal dislocation dynamics code, adapted to Hexagonal Close Packed metals, has been used. Various configurations have been systematically computed considering different glide planes, basal or prismatic, and different characters, edge or screw, for gliding dislocations with 〈a〉-type Burgers vectors. Simulations show various interaction mechanisms such as (i) absorption of a loop on an edge dislocation leading to the formation of a double super-jog, (ii) creation of a helical turn, on a screw dislocation, that acts as a strong pinning point or (iii) sweeping of a loop by a gliding dislocation. It is shown that the clearing of loops is more favorable when the dislocation glides in the basal plane than in the prismatic plane explaining the easy dislocation channeling in the basal plane observed after neutron irradiation by transmission electron microscopy.

  7. Dislocation dynamics simulations of interactions between gliding dislocations and radiation induced prismatic loops in zirconium

    Drouet, Julie; Dupuy, Laurent; Onimus, Fabien; Mompiou, Frédéric; Perusin, Simon; Ambard, Antoine

    2014-06-01

    The mechanical behavior of Pressurized Water Reactor fuel cladding tubes made of zirconium alloys is strongly affected by neutron irradiation due to the high density of radiation induced dislocation loops. In order to investigate the interaction mechanisms between gliding dislocations and loops in zirconium, a new nodal dislocation dynamics code, adapted to Hexagonal Close Packed metals, has been used. Various configurations have been systematically computed considering different glide planes, basal or prismatic, and different characters, edge or screw, for gliding dislocations with -type Burgers vectors. Simulations show various interaction mechanisms such as (i) absorption of a loop on an edge dislocation leading to the formation of a double super-jog, (ii) creation of a helical turn, on a screw dislocation, that acts as a strong pinning point or (iii) sweeping of a loop by a gliding dislocation. It is shown that the clearing of loops is more favorable when the dislocation glides in the basal plane than in the prismatic plane explaining the easy dislocation channeling in the basal plane observed after neutron irradiation by transmission electron microscopy.

  8. Extracting dislocations and non-dislocation crystal defects from atomistic simulation data

    We describe a novel method for extracting dislocation lines from atomistic simulation data in a fully automated way. The dislocation extraction algorithm (DXA) generates a geometric description of dislocation lines contained in an arbitrary crystalline model structure. Burgers vectors are determined reliably, and the extracted dislocation network fulfills the Burgers vector conservation rule at each node. All remaining crystal defects (grain boundaries, surfaces, etc), which cannot be represented by one-dimensional dislocation lines, are output as triangulated surfaces. This geometric representation is ideal for visualization of complex defect structures, even if they are not related to dislocation activity. In contrast to the recently proposed on-the-fly dislocation detection algorithm (ODDA) Stukowski (2010 Modelling Simul. Mater. Sci. Eng. 18 015012) the new method is extremely robust. While the ODDA was designed for a computationally efficient on-the-fly analysis, the DXA method enables a detailed analysis of dislocation lines even in highly distorted crystal regions, as they occur, for instance, close to grain boundaries or in dense dislocation networks

  9. Dislocation engineered silicon light emitting devices

    The influence of boron-induced dislocation loops on the luminescence efficiency of silicon-based light-emitting diodes is investigated. Luminescence measurements and transmission-electron-microscopy images from devices fabricated by boron implantation into crystalline silicon, and subsequently processed under different conditions to form dislocation loops of different size and densities, were compared. Light emitting devices were also fabricated in an otherwise identical but a pre-amorphized substrate, to prevent boron-induced loop formation. The results demonstrate a strong correlation between the dislocation loop density and areal coverage, and the light emission efficiency. The devices produced in the pre-amorphized substrate, without dislocation loops, show strongly quenched light emission

  10. Dislocation equation from the lattice dynamics

    Wang Shaofeng [Institute for Structure and Function, Chongqing University, Chongqing 400044 (China)

    2008-01-11

    A dislocation equation satisfied by both horizontal displacement parallel to the glide plane and vertical displacement perpendicular to the glide plane has been derived generally from the lattice dynamics. In the slow-varying approximation that can be well applied to the dislocation, the equation has been changed into an integro-differential equation that possesses a universal form except the coefficients. If the higher-order derivatives of the displacement are canceled, the classic Peierls equation is recovered. The terms proportional to the higher-order derivatives represent the lattice effects that cannot be obtained in the continuum theory, and cannot be neglected in the core of the dislocation. The results are helpful to link the plasticity with the electronic structure of material because it is rigorously shown that the dislocation structure is mainly controlled by a few factors.

  11. Quenched pinning and collective dislocation dynamics.

    Ovaska, Markus; Laurson, Lasse; Alava, Mikko J

    2015-01-01

    Several experiments show that crystalline solids deform in a bursty and intermittent fashion. Power-law distributed strain bursts in compression experiments of micron-sized samples, and acoustic emission energies from larger-scale specimens, are the key signatures of the underlying critical-like collective dislocation dynamics - a phenomenon that has also been seen in discrete dislocation dynamics (DDD) simulations. Here we show, by performing large-scale two-dimensional DDD simulations, that the character of the dislocation avalanche dynamics changes upon addition of sufficiently strong randomly distributed quenched pinning centres, present e.g. in many alloys as immobile solute atoms. For intermediate pinning strength, our results adhere to the scaling picture of depinning transitions, in contrast to pure systems where dislocation jamming dominates the avalanche dynamics. Still stronger disorder quenches the critical behaviour entirely. PMID:26024505

  12. Hip dysplasia and congenital hip dislocation

    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.

  13. Dislocation dynamics of web type silicon ribbon

    Dillon, O. W., Jr.; Tsai, C. T.; De Angelis, R. J.

    1987-01-01

    Silicon ribbon grown by the dendritic web process passes through a rapidly changing thermal profile in the growth direction. This rapidly changing profile induces stresses which produce changes in the dislocation density in the ribbon. A viscoplastic material response function (Haasen-Sumino model) is used herein to calculate the stresses and the dislocation density at each point in the silicon ribbon. The residual stresses are also calculated.

  14. Investigation of the Dynamics of a Screw Dislocation in Copper

    Kolupaeva, S. N.; Petelina, Yu. P.; Polosukhin, K. A.; Petelin, A. E.

    2015-08-01

    A modification of the mathematical model of forming the crystallographic shear band is proposed in which the strength of elastic interaction between all dislocations of the forming dislocation pileups is taken into account in addition to the Peach-Keller force; lattice, impurity, and dislocation friction; linear tension; viscous braking; and intensity of generation of point defects behind kinks. The model is used to investigate the influence of the dislocation density on the time characteristics of the formation of dislocation loops in copper.

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

    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.

  16. Magnetic resonance imaging of hip joint cartilage and labrum

    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.

  17. Computing of dislocation motion in a material: coupling of molecular dynamics and dislocation dynamics

    Recently, molecular dynamics (MD) computer simulation technique is becoming very promising approach to predict materials behavior such as dislocation motion owing to the development of reliable inter-atomic potentials and high-speed modern computers. The MD technique enables us to perform very realistic simulation of local interactions between a dislocation and an obstacle, for example, if we could handle more than 10 million atoms in a model crystal. However, even such a very large scale MD simulation is still insufficient to investigate real complex interactions that occur in real materials in terms of the length and time scales. On the other hand, a new computer simulation technique known as a dislocation dynamics (DD) has been studied in recent years. This method simulates dislocation behavior based on the elasticity theory of dislocation motion, and enables us to study the phenomena of the length scale up to tens of micro-meters which is a typical length scale for crystal grains. The method also predicts the stress-strain behavior of the model crystal. However, one disadvantage of DD is that the elasticity theory does not predict the behavior of dislocations when they meet obstacles. In this paper, we couple the MD and DD techniques to perform simulations of complex dislocation behavior in nickel-base super-alloy. Information on the local interactions between a dislocation and obstacles, such as γ' phase in the nickel-base super-alloy, are obtained from large-scale MD simulations. The results are modeled as local rules between a dislocation and obstacles, and the rule is used in the DD simulations to predict the dislocation behavior in a complex material. In the MD simulation of the interaction between a γ' particle with a diameter of about 8 nm and a straight edge dislocation, we can clearly observe that the motion of a straight dislocation, which extends to two partial dislocations, is delayed at he position where the leading partial dislocation meets the

  18. Crystal Dislocations with Different Orientations and Collisions

    Patrizi, Stefania; Valdinoci, Enrico

    2015-07-01

    We study a parabolic differential equation whose solution represents the atom dislocation in a crystal for a general type of Peierls-Nabarro model with possibly long range interactions and an external stress. Differently from the previous literature, we treat here the case in which such dislocation is not the superposition of transitions all occurring with the same orientations (i.e. opposite orientations are allowed as well). We show that, at a long time scale, and at a macroscopic space scale, the dislocations have the tendency to concentrate as pure jumps at points which evolve in time, driven by the external stress and by a singular potential. Due to differences in the dislocation orientations, these points may collide in finite time. More precisely, we consider the evolutionary equation where is the atom dislocation function at time t > 0 at the point is an integro-differential operator of order is a periodic potential, is an external stress and is a small parameter that takes into account the small periodicity scale of the crystal. We suppose that is the superposition of N- K transition layers in the positive direction and K in the negative one (with ); more precisely, we fix points and we take Here is either -1 or 1, depending on the orientation of the transition layer u, which in turn solves the stationary equation . We show that our problem possesses a unique solution and that, as , it approaches the sum of Heaviside functions H with different orientations centered at points x i ( t), namely The point x i evolves in time from , being subject to the external stress and a singular potential, which may be either attractive or repulsive, according to the different orientation of the transitions; more precisely, the speed is proportional to The evolution of such a dynamical system may lead to collisions in finite time. We give a detailed description of such collisions when N = 2, 3 and we show that the solution itself keeps track of such collisions; indeed, at

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

    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.

  20. Advances in the theory of the Hall-Petch relation, dislocation pileups and dislocation sources

    Friedman, Lawrence Henry

    Advances in the theory of dislocations are reported. The Hall-Petch relation is extended, and a continuum level simulation of curvilinear dislocations is developed and used to study the operation of Frank-Read sources. The Hall-Petch relation states that the yield stress, sigma y, or strength against plastic deformation of polycrystalline materials is enhanced by decreasing the grain diameter: sigma y = Kd--1/2 + sigma 0, with K and sigma0 constants. One explanation of this relation is that yielding results from stress concentrated by queues of dislocations known as pileups. The pileup theory of the Hall-Petch relation is extended in two ways. First, two important aspects of pileup formation are incorporated into the theory: the existence of a threshold stress for dislocation production and the necessity of a finite-sized dislocation-free region in which a dislocation source may operate. Using a continuum theory of dislocation pileups, a closed form expression is obtained for the dependence of yield stress on grain size and source characteristics. The continuum model agrees closely with the corresponding discrete dislocation model. Second, a scaling theory describing the strength of lamellar materials is developed. The Hall-Petch relation is found to result from the similarity between dislocation densities of pileups of different lengths and under different applied stresses. For multilayers, the scaling theory predicts sigma y = KΛ--a + sigma0, where Λ is the compositional wavelength of the multilayer and a is a material dependent exponent. The scaling theory is then enlarged to incorporate parameters important to the operation of dislocation sources. The simulation of curvilinear dislocations, based on linear isotropic elasticity theory, includes self stress and dislocation-dislocation interactions. The operation stress of a Frank-Read source is found as a function of source size. Additionally, the plastic strain produced by a continuously operating source was

  1. Scaling properties of dislocation simulations in the similitude regime

    Dislocation systems exhibit well-known scaling properties such as the Taylor relationship between flow stress and dislocation density, and the ‘law of similitude’ linking the flow stress to the characteristic wavelength of dislocation patterns. Here, we discuss the origin of these properties, which can be related to generic invariance properties of the equations of evolution of discrete dislocation systems, and their implications for a wide class of models of dislocation microstructure evolution. We demonstrate that under certain conditions dislocation simulations carried out at different stress, dislocation density and strain rate can be considered to be equivalent, and we study the range of deformation conditions (‘similitude regime’) over which this equivalence can be expected to hold. In addition, we discuss restrictions imposed by the stated invariance properties for density-based, non-local or stochastic models of dislocation microstructure evolution, and for dislocation patterns and size effects. (paper)

  2. Dislocation dynamics in multiwalled carbon nanotubes at high temperatures.

    Huang, J Y; Ding, F; Yakobson, B I

    2008-01-25

    Dislocation dynamics dictate the mechanical behavior of materials. Dislocations in periodic crystalline materials have been well documented. On the contrary, dislocations in cylindrical carbon nanotubes, particularly in multiwalled carbon nanotubes (MWCNTs), remain almost unexplored. Here we report that a room temperature 1/2 sessile dislocation in a MWCNT becomes highly mobile, as characterized by its glide, climb, and the glide-climb interactions, at temperatures of about 2000 degrees C. The dislocation glide leads to the cross-linking of different shells; dislocation climb creates nanocracks; and the interaction of two 1/2 dislocations creates kinks. We found that dislocation loops act as channels for mass transport. These dislocation dynamics are drastically different from that in conventional periodic crystalline materials due to the cylindrical, highly anisotropic structures of MWCNTs. PMID:18232998

  3. Bauschinger effect in thin metal films: Discrete dislocation dynamics study

    Davoudi, Kamyar M.; Nicola, Lucia; Vlassak, Joost J.

    2014-01-01

    The effects of dislocation climb on plastic deformation during loading and unloading are studied using a two-dimensional discrete dislocation dynamics model. Simulations are performed for polycrystalline thin films passivated on both surfaces. Dislocation climb lowers the overall level of the stress inside thin films and reduces the work hardening rate. Climb decreases the density of dislocations in pile-ups and reduces back stresses. These factors result in a smaller Bauschinger effect on unloading compared to simulations without climb. As dislocations continue to climb at the onset of unloading and the dislocation density continues to increase, the initial unloading slope increases with decreasing unloading rate. Because climb disperses dislocations, fewer dislocations are annihilated during unloading, leading to a higher dislocation density at the end of the unloading step.

  4. Radiographic evaluation of anterior dislocation of the shoulder

    To establish radiographic criteria to choose the most appropriate technique of reduction for each type of anterior glenohumeral dislocation, and to determine the type of dislocation which requires general anesthesia. Material and Methods: Radiography in two different projections was performed in 67 patients with antero-inferior shoulder dislocations before a reduction attempt. The method proposed by Boss-Holzach-Matter was used as the primary technique for all shoulder dislocations. Results: Most subcoracoid dislocations (84.4%) could be reduced by the Boss-Holzach-Matter method while only a few subglenoid dislocations (15.8%) were reducible by this technique. Displaced associated fractures significantly reduced the success rate of the reduction attempts. Conclusion: Anterior dislocations of the shoulder require different methods of reduction depending upon the type (sub-group) of dislocation. Reduction of subglenoid dislocations with associated greater tuberosity fracture should be performed under general anesthesia to avoid head-splitting fracture

  5. Hybrid Dislocated Control and General Hybrid Projective Dislocated Synchronization for Memristor Chaotic Oscillator System

    Junwei Sun

    2014-01-01

    Full Text Available Some important dynamical properties of the memristor chaotic oscillator system have been studied in the paper. A novel hybrid dislocated control method and a general hybrid projective dislocated synchronization scheme have been realized for memristor chaotic oscillator system. The paper firstly presents hybrid dislocated control method for stabilizing chaos to the unstable equilibrium point. Based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization has been studied for the drive memristor chaotic oscillator system and the same response memristor chaotic oscillator system. For the different dimensions, the memristor chaotic oscillator system and the other chaotic system have realized general hybrid projective dislocated synchronization. Numerical simulations are given to show the effectiveness of these methods.

  6. Influence of dislocation and dislocation loop biases on microstructures simulated by rate equation cluster dynamics

    Jourdan, T.

    2015-12-01

    Sensitivity of microstructures under irradiation to absorption biases of dislocations and dislocation loops is investigated by rate equation cluster dynamics (RECD). Contrary to standard rate theory which is often used to estimate sensitivity of cavity growth to biases, it is possible with RECD to quantify the effect of biases on nucleation, growth and coarsening of loops and cavities. For this purpose simple and accurate expressions for dislocation and dislocation loop biases are derived, based on finite element calculations. They are used in a RECD code to quantify the effect of biases on microstructures of austenitic steels irradiated with electrons. It is shown that biases have a strong influence not only on the loop and dislocation network evolutions, but also on cavity nucleation. Sensitivity to some other parameters of the model is also discussed.

  7. Dislocation-void interaction in Fe: A comparison between molecular dynamics and dislocation dynamics

    Hafez Haghighat, S.M. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, CH 5232 Villigen PSI (Switzerland)], E-mail: masood.hafez@psi.ch; Fivel, M.C. [SIMAP-GPM2, CNRS/INPG, BP 46, 38402 St Martin d' Heres cedex (France); Fikar, J.; Schaeublin, R. [Ecole Polytechnique Federale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas, Association Euratom-Confederation Suisse, CH 5232 Villigen PSI (Switzerland)

    2009-04-30

    Multiscale 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 concerns the influence of irradiation on the plasticity of pure Fe and focuses on the interaction of a single dislocation with a spherical void at various geometries. MD simulation shows that the void strengthening is proportional to the interaction area. Stress field around the void influences also the dislocation passage. DDD calculation coupled to finite element method (FEM) is used to simulate the interaction of an edge dislocation with a void. DDD calculations present a good match to the MD simulation results at the near-atomic scale. They highlight the impact of image forces on the dislocation due to the free internal surface of the void and the one of its surrounding stress field.

  8. Elbow joint stability following experimental osteoligamentous injury and reconstruction

    Deutch, Søren R; Jensen, Steen Lund; Tyrdal, Stein; Olsen, Bo S; Sneppen, Otto

    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 al...

  9. Elbow joint stability following experimental osteoligamentous injury and reconstruction

    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...

  10. Molecular dynamics simulation of dislocation intersections in aluminum

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

    2003-12-20

    The molecular dynamics method is used to simulate dislocation intersection in aluminum containing 1.6x10{sup 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.

  11. Isolated dorsal dislocation of the tarsal naviculum.

    Hamdi, Kaziz; Hazem, Ben Ghozlen; Yadh, Zitoun; Faouzi, Abid

    2015-01-01

    Isolated dislocation of the tarsal naviculum is an unusual injury, scarcely reported in the literature. The naviculum is surrounded by the rigid bony and ligamentous support hence fracture dislocation is more common than isolated dislocation. The mechanism and treatment options remain unclear. In this case report, we describe a 31 year old man who sustained an isolated dorsal dislocation of the left tarsal naviculum, without fracture, when he was involved in a motor vehicle collision. The reported mechanism of the dislocation is a hyper plantar flexion force applied to the midfoot, resulting in a transient disruption of the ligamentous support of the naviculum bone, with dorsal displacement of the bone. The patient was treated with open reduction and Krischner-wire fixation of the navicular after the failure of closed reduction. The wires were removed after 6 weeks postoperatively. Physiotherapy for stiffness and midfoot pain was recommended for 2 months. At 6 months postoperatively, limping, midfoot pain and weakness were reported, no X-ray abnormalities were found. The patient returned to his obvious activities with a normal range of motion. PMID:26806978

  12. Isolated dorsal dislocation of the tarsal naviculum

    Kaziz Hamdi

    2015-01-01

    Full Text Available Isolated dislocation of the tarsal naviculum is an unusual injury, scarcely reported in the literature. The naviculum is surrounded by the rigid bony and ligamentous support hence fracture dislocation is more common than isolated dislocation. The mechanism and treatment options remain unclear. In this case report, we describe a 31 year old man who sustained an isolated dorsal dislocation of the left tarsal naviculum, without fracture, when he was involved in a motor vehicle collision. The reported mechanism of the dislocation is a hyper plantar flexion force applied to the midfoot, resulting in a transient disruption of the ligamentous support of the naviculum bone, with dorsal displacement of the bone. The patient was treated with open reduction and Krischner-wire fixation of the navicular after the failure of closed reduction. The wires were removed after 6 weeks postoperatively. Physiotherapy for stiffness and midfoot pain was recommended for 2 months. At 6 months postoperatively, limping, midfoot pain and weakness were reported, no X-ray abnormalities were found. The patient returned to his obvious activities with a normal range of motion.

  13. Dislocation dynamics in an anisotropic stripe pattern.

    Kamaga, Carina; Ibrahim, Fatima; Dennin, Michael

    2004-06-01

    The dynamics of dislocations confined to grain boundaries in a striped system are studied using electroconvection in the nematic liquid crystal N4. In electroconvection, a striped pattern of convection rolls forms for sufficiently high driving voltages. We consider the case of a rapid change in the voltage that takes the system from a uniform state to a state consisting of striped domains with two different wave vectors. The domains are separated by domain walls along one axis and a grain boundary of dislocations in the perpendicular direction. The pattern evolves through dislocation motion parallel to the domain walls. We report on features of the dislocation dynamics. The kinetics of the domain motion is quantified using three measures: dislocation density, average domain wall length, and total domain wall length per area. All three quantities exhibit behavior consistent with power-law evolution in time, with the defect density decaying as t(-1/3), the average domain wall length growing as t(1/3), and the total domain wall length decaying as t(-1/5). The two different exponents are indicative of the anisotropic growth of domains in the system. PMID:15244714

  14. A Comparative Study on the Close Reduction of Arytenoid Dislocation under Indirect and Direct Laryngoscope

    王志斌; 刘秋润

    2002-01-01

    Summary: To assess the curative effects of different reduction techniques on the dislocation ofcricoarytenoid joint caused by intubation, indirect laryngoscope (IL) and direct laryngoscope (DL)were utilized for the closed reduction of the displaced arytenoid under local anesthesia. 23 patientswho underwent the reduction for dislocated arytenoid under IL or DL from January 1991 to June2001 were reviewed. The data were collected on the duration of the laryngeal injury, times of re-ceiving reduction, side-effects after the treatment and the period for voice to return to normal.The relationship between the duration of the laryngeal lesion and the period of the voice rehabilita-tion was examined. 13 patients received the reduction under IL and 10 patients under DL. Exceptthe times of the reduction, which showed significant difference, no differences were found betweenIL group and DL group in the course and the period of voice rehabilitation, as well as sore throatafter the manipulation. The patients' voice recovery was positively related to their course of dis-ease in both IL and DL group. It is concluded that the recovery of normal voice is obviously affect-ed by the duration of arytenoid dislocation. The reduction under IL is as effective as under DL inthe treatment of arytenoid dislocation. Reduction by DL is better suit the patients with long timecourse of disease.

  15. High dislocation density of tin induced by electric current

    Liao, Yi-Han; Liang, Chien-Lung; Lin, Kwang-Lung, E-mail: matkllin@mail.ncku.edu.tw [Department of Material Science and Engineering, National Cheng Kung University, Tainan 70101, Taiwan, R. O. C (China); Wu, Albert T. [Department of Chemical and Material Engineering, National Central University, Jhongli 32001, Taiwan, R. O. C (China)

    2015-12-15

    A dislocation density of as high as 10{sup 17} /m{sup 2} in a tin strip, as revealed by high resolution transmission electron microscope, was induced by current stressing at 6.5 x 10{sup 3} A/ cm{sup 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.

  16. Joint pain

    ... or conditions. It may be linked to arthritis , bursitis , and muscle pain . No matter what causes it, ... Autoimmune diseases such as rheumatoid arthritis and lupus Bursitis Chondromalacia patellae Crystals in the joint: gout (especially ...

  17. Clusters of dislocations in a carrier wave

    Clusters of point dislocations (wave vortices) may be present within an otherwise perfect plane scalar wave, a carrier wave in two dimensions, which may be evanescent. The question arises: is it possible to deduce the orientation of the distant undisturbed carrier wave purely from local information about the cluster itself? For groups of two and four dislocations in a carrier wave, this may be done by using no other information than the local phase map or the individual positions of the singularities. The maximum number possible in a cluster with a carrier wave is 4 and the total strength (topological charge) of a cluster is always zero or ± 2. The study includes an examination of degenerate dislocations of strength zero or ± 1

  18. Successful Conservative Management of a Dislocated IUD

    Hasan Ali Inal

    2015-01-01

    Full Text Available Background. Intrauterine contraceptive devices (IUDs are widely utilized all over the world owing to their low cost and high efficacy. Uterine perforation is a rare complication that may occur at IUD insertion resulting in extrauterine location of the IUD. Traditionally, surgical removal of dislocated IUDs has been recommended. Case. A 68-year-old patient who had an IUD (Lippes loop inserted 32 years ago and whose routine examination incidentally revealed a dislocated IUD in the abdominal cavity. The patient remained asymptomatic during three years of follow-up and the IUD was left in place. Conclusion. Asymptomatic patients, whose vaginal examinations and ultrasonography or X-ray results reveal a dislocated IUD, may benefit from conservative management.

  19. Micromechanics and dislocation theory in anisotropic elasticity

    Lazar, Markus

    2016-01-01

    In this work, dislocation master-equations valid for anisotropic materials are derived in terms of kernel functions using the framework of micromechanics. The second derivative of the anisotropic Green tensor is calculated in the sense of generalized functions and decomposed into a sum of a $1/R^3$-term plus a Dirac $\\delta$-term. The first term is the so-called "Barnett-term" and the latter is important for the definition of the Green tensor as fundamental solution of the Navier equation. In addition, all dislocation master-equations are specified for Somigliana dislocations with application to 3D crack modeling. Also the interior Eshelby tensor for a spherical inclusion in an anisotropic material is derived as line integral over the unit circle.

  20. Rare Inferior Shoulder Dislocation (Luxatio Erecta

    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.

  1. Discrete dislocation dynamics: an important recent break-through in the modelling of dislocation collective behaviour; Dynamique des dislocations discretes: modelisation du comportement collectif des dislocations

    Fivel, M.C. [SIMaP-GPM2, CNRS, INP Grenoble, 38 - Saint-Martin-d' Heres (France)

    2008-04-15

    Recent results obtained by 3-dimensional discrete Dislocation Dynamics (DD) simulations are reviewed. First, in the case of the fatigued AISI 316L stainless steel, it is shown how DD simulations can both explain the formation of persistent slip bands and give a criterion for crack initiation. The same study is performed in the case of precipitate hardened metals where the precipitate size plays a crucial role. Secondly, we show how molecular dynamics (MD) simulations can feed the DD simulations for two applications. The first concerns the modelling of body-centred-cubic Fe for which the dislocation mobility is derived from MD simulations. The second considers the modelling of irradiated stainless steels (face-centred-cubic crystals), where MD is used to define the local rules of interactions between dislocations and Frank loops. (author)

  2. Electron paramagnetic resonance at dislocations in germanium

    Pakulis, E.J.

    1982-06-01

    The first observation of the paramagnetic resonance of electrons at dislocations in germanium single crystals is reported. Under subband gap optical excitation, two sets of lines are detected: four lines about the <111> axes with g/sub perpendicular to/ = 0.34 and g/sub parallel/ = 1.94, and 24 lines with g/sub perpendicular to/ = 0.73 and g/sub parallel/ = 1.89 about <111> axes with the six-fold 1.2/sup 0/ distortion. This represents the first measurement of the disortion angle of a dislocation dangling bond. The possibility that the distortion results from a Peierls transition along the dislocation line is discussed.

  3. C1-C2 rotary subluxation following posterior stabilization for congenital atlantoaxial dislocation.

    Behari S

    2000-04-01

    Full Text Available The authors report a rare complication of C1-C2 rotary subluxation in two children following posterior stabilization for congenital atlantoaxial dislocation (AAD. A patient, with mobile AAD, underwent Brook′s C1-C2 fusion while the other, with fixed AAD, underwent transoral decompression followed by Jain′s occipitocervical fusion. A pre-existing ligamentous laxity associated with an asymmetrical wire tightening or slippage of the wires due to rotation of the neck in the former, and the drilling of the C1-C2 lateral joints during the transoral procedure in the latter, could have contributed to the rotary subluxation. Both patients presented with persistent torticollis due to fusion in an asymmetrical position with dislocated facet joints. Rotary C1-C2 subluxation, when coexisting with anterior dislocation, has the potential to cause severe and occasionally fatal cord compression. Well defined criteria to diagnose this entity by conventional radiology exist, however, due to the overlap of anatomy, the condition is often overlooked. In the present study, three dimensional reconstruction images using helical computerized tomography were very useful in delineating the subluxation and in planning its surgical reduction and arthrodesis.

  4. Management and Prognostic Factors for Delayed Reconstruction of Neglected Posterior Shoulder Fracture-Dislocation

    Bekmezci

    2015-12-01

    Full Text Available Introduction Posterior fracture-dislocations of the shoulder are rare conditions. Misdiagnosis can occur in 50% - 80% of the patients. Due to the size of the lesion, stability of the joint could not be achieved with transfer of subscapular tendon or tuberosity. Case Presentation A 54-year-old male patient was referred to our hospital with a neglected posterior shoulder fracture-dislocation. Functional results of the patient, and technical informations were explained in this case report. The reverse Hill-Sachs lesion involved 40% of the articular surface. Depressed and malunited fragment was elevated, and fixated to the humeral head. Conclusions Glenohumeral joint reduction with reconstruction of the humeral head seems to be possible even in a neglected locked posterior shoulder fracture-dislocation. If the depressed osteochondral fragment is still spheric, signs of the avascular necrosis are absent on CT, and malunion of the fragment has occurred, it is quite possible to reconstruct the head. Although results of the case are good, it is worthwhile to follow these patients for long-term complications.

  5. Dislocation dynamics modelling of dislocation-loop interactions in irradiated metals

    Rong, Zhouwen [University of Liverpool; Mohles, Volker [University of Munster, Germany; Bacon, David J [University of Liverpool; Osetskiy, Yury N [ORNL

    2005-01-01

    The resistance dislocation loops provide to the glide of dislocations is an important element of several features of plasticity of irradiated metals. In the present work, a dislocation dynamics model based on the elasticity treatment of dislocations, with self-stress effects included, has been used to investigate the critical applied stress required for a gliding dislocation to overcome the stress field of a row of sessile loops near the glide plane. The critical stress has been determined for wide ranges of loop size, spacing and distance from the glide plane. Various approximations to the loop distribution have been tested, including an edge dipole, a single dislocation and a row of infinitesimal loops. The infinitesimal loop model, in particular, is shown to give good agreement with the accurate simulation data over a wide range of loop size and spacing. The ranges of applicability are discussed and compared with previous treatments in which such approximations have been used to investigate hardening due to dislocation-loop interactions.

  6. A preliminary investigation of dislocation cell structure formation in metals using continuum dislocation dynamics

    Xia, S. X.; El-Azab, A.

    2015-08-01

    A continuum dislocation dynamics model capable of capturing the cellular arrangements of dislocations in deformed crystals is presented. A small strain formulation of the model is given, followed by sample results of stress-strain behaviour, dislocation density evolution, dislocation cell pattern, lattice rotation, and geometrically necessary dislocation density and strain energy density distributions. An important finding of the current work is that dislocations form patterns under all circumstances due to their long range interactions. It is found, however, that the famous cell structure pattern forms when cross slip is activated. It is also found that cells are 3D sub-regions surrounded by dislocations walls in all directions, and they form, disappear, and reappear as a result of the motion of cell walls and formation of new walls by cross slip. It is further found that the average cell size is connected with the applied resolved shear stress according to the similitude principle observed in related experiments. The importance of these results is briefly discussed in the context of recrystallization.

  7. Dislocation microstructure evolution in cyclically twisted microsamples: a discrete dislocation dynamics simulation

    Miniaturization in technical devices has increased interest in the investigation of the deformation and fatigue behaviour of metals in the micrometre regime. Due to the small dimensions of these devices, mechanical properties depend on the motion of a marginal number of dislocations. In this paper, the evolution of dislocation microstructure in torsion loaded single crystalline aluminium wires is analysed by three-dimensional discrete dislocation dynamics simulations. It is shown that the size of pile-ups and the number of the active slip systems is significantly influenced by cross-slip events independent of the crystallographic orientation. Dislocations are driven by the stress gradient from the applied loading to move into the centre of the sample. These dislocations cannot escape through the surface because of the reversal of the sign of the stress in the centre of the sample. If the micrometre-sized specimens are untwisted, the remaining dislocation microstructure in these samples depends on the maximum torsion angle reached before unloading. The larger the torsion angle, the higher is the remaining dislocation density in the unloaded specimens. These results are discussed with respect to cyclic deformation mechanisms at small scale

  8. Contribution to the study of screw dislocations

    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)

  9. Dislocation dynamics in SiGe alloys

    Yonenaga, I.

    2013-11-01

    The dislocation velocities and mechanical strength of bulk crystals of SixGe1-x alloys grown by the Czochralski method have been investigated by the etch pit technique and compressive deformation tests, respectively. Velocity of dislocations in the SiGe alloys of the composition range 0.004 < x < 0.08 decreases monotonically with an increase in Si content at temperature 450-700°C and under stress 3-24MPa. In contrast, velocity of dislocations in the composition range 0.92 < x < 1 first increases, then decreases and again increases with a decrease in Si content at temperature 750-850°C and under stress 3-30MPa. The velocity of dislocations was quantitatively evaluated as functions of stress and temperature. Stress-strain behaviour in the yield region of the SiGe alloys of composition 0 < x < 0.4 is similar to that of Ge at temperatures lower than about 600°C. However, the yield stress becomes temperature-insensitive at high temperatures and increases with increasing Si content. The stress-strain curves of the SiGe alloys of composition 0.95 < x < 1 are similar to those of pure Si at temperatures 800-1000°C and the yield stress increases with decreasing Si content down to x = 0.95. The yield stress of the SiGe alloys is dependent on the composition, being proportional to x(1-x), showing a maximum around x ≈ 0.5. Built-in stress fields related to local fluctuation of the alloy composition and the dynamic development of a solute atmosphere around the dislocations, may suppress the activities of dislocations and lead to the hardening of SiGe alloys.

  10. Dislocation dynamics in SiGe alloys

    The dislocation velocities and mechanical strength of bulk crystals of SixGe1−x alloys grown by the Czochralski method have been investigated by the etch pit technique and compressive deformation tests, respectively. Velocity of dislocations in the SiGe alloys of the composition range 0.004 < x < 0.08 decreases monotonically with an increase in Si content at temperature 450–700°C and under stress 3–24MPa. In contrast, velocity of dislocations in the composition range 0.92 < x < 1 first increases, then decreases and again increases with a decrease in Si content at temperature 750-850°C and under stress 3–30MPa. The velocity of dislocations was quantitatively evaluated as functions of stress and temperature. Stress-strain behaviour in the yield region of the SiGe alloys of composition 0 < x < 0.4 is similar to that of Ge at temperatures lower than about 600°C. However, the yield stress becomes temperature-insensitive at high temperatures and increases with increasing Si content. The stress-strain curves of the SiGe alloys of composition 0.95 < x < 1 are similar to those of pure Si at temperatures 800–1000°C and the yield stress increases with decreasing Si content down to x = 0.95. The yield stress of the SiGe alloys is dependent on the composition, being proportional to x(1−x), showing a maximum around x ≈ 0.5. Built-in stress fields related to local fluctuation of the alloy composition and the dynamic development of a solute atmosphere around the dislocations, may suppress the activities of dislocations and lead to the hardening of SiGe alloys

  11. High-temperature discrete dislocation plasticity

    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.

  12. Geometry of dislocated de Broglie waves

    Holland, P. R.

    1987-04-01

    The geometrical structures implicit in the de Broglie waves associated with a relativistic charged scalar quantum mechanical particle in an external field are analyzed by employing the ray concept of the causal interpretation. It is shown how an osculating Finslerian metric tensor, a torsion tensor, and a tetrad field define respectively the strain, the dislocation density, and the Burgers vector in the “natural state” of the wave, which is a non-Riemannian space of distant parallelism. A quantum torque determined by the quantum potential is introduced and the example of a screw dislocated wave is discussed.

  13. Dislocation evolution with rheological forming of metal

    1999-01-01

    It is known that some internal defects exist in metal materials. Preliminary attempt to relate dislo cation evolution with metal rheological forming was done. By the attempt, it is learned that the evolution of dislocation density p( x, y, t ) is essentially the change of n independent internal variables qα (α = 1, 2, …n ) with material. The preliminary research in theory and experiments showed that dislocations piling-up could be avoided. One can improve the internal microstructure and mechanical properties of products by rheological forming method.

  14. [Clinical and ultrasonic diagnosis of congenital hip dislocation (dynamics of changes in early therapy)].

    Poul, J; Procházka, J; Klimsová, J; Janovec, M; Bajerová, J; Jíra, I; Straka, M; Sommernitz, M

    1990-08-01

    The authors present part of their prospective epidemiological study of congenital dysplasia of hip joints within which newborns were examined by ultrasonogram prior to the beginning of the therapy. Apart from the standard examination in the frontal plane after Graf they examined on principle also the ultrasonographic stability by the dynamic test after Schuler as well as by the application of the probe anteriorly with the simultaneous provocation according to Palmén. The authors have processed pathological ultrasonographic findings in 53 newborns (64 hip joints). The technique of the examination by ultrasound from the anterior approach is explained in detail. The comparison of both dynamic tests has shown that the examination from the anterior approach is considerably more sensitive than Schuler's dynamic test and also fully correlates with the clinical finding. It is a fact that the shift of the head in the flexion dorsally represents the most important component of the movement in unstable hip joint during provocation, it is far more noticeable than the lateralization of the head or the shift in the cranial direction. After achieving ultrasonographic stability the classical Graf method is sufficient for the registration of residual changes on the acetabular rim. The follow-up of patients until their complete healing has shown a surprisingly rapid remodellation of hip joints. The whole complex of clinically unstable hip joints has been divided into subgroups according to Graf classification. In type IIc or IId on the basis of ultrasonographic examination from the anterior approach the stable joints from the ultrasonographic viewpoint have been distinguished from unstable ones. The follow-up carried out in short intervals has shown that of longest duration is the remodellation of total dislocation and, on the contrary, of shortest duration is the healing of joints in the IIc or IId type. An absolute majority of affected hip joints have become normal until 3rd

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

    Hafez Haghighat, S.M.; Schaeublin, R. [CRPP- EPFL, Association EURATOM-Confederation Suisse, ODGA-C103, Villigen-PSI (Switzerland); Fivel, M.C. [SIMAP-GPM2, CNRS/INPG, 38 - St Martin d' Heres (France)

    2007-07-01

    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

  16. Application of MRI in indirect temporomandibular joint injury without condylar fracture

    WANG Mei-hao; WU En-fu; FANG Yi-ming; LI Jin-lin; WANG Jing-xiao; YUAN Xiang-zhi; DENG Yong; LI Jian-ce; YANG Yun-jun; CHEN Wei-jian

    2007-01-01

    Objective: To discuss the application of MRI in indirect temporomandibular joint injury without condylar fracture. Methods: MRI examination on temporomandibular joint was conducted in 28 patients with indirect injury to temporomandibular joint without condylar fracture. The scanning sequence included T1WI, PDWI on oblique sagittal section at both open and closed mouth positions,and T1WI,T2WI on oblique coronal section. The MRI appearance was analyzed by 2 senior radiologists. Results: Among the 56 temporomandibular joints of 28 patients, 35 joints exhibited pathological changes on MRI, in which there were 9 bone injuries, 21 articular disc dislocation, 24 intracapsular hematocele and hydrops. Conclusions: MRI can clearly reveal bone injury, articular disc dislocation as well as articular capsule abnormality in the indirect injury of temporomandibular joint without condylar fracture. It is highly advocated in clinical use.

  17. A model for nucleation of tin whisker through dislocation behavior

    Nakai, K.; Sakamoto, T.; Kobayashi, S.; Takamizawa, M.; Murakami, K.; Hino, M.

    2009-05-01

    A model for the nucleation and growth processes of Sn whisker is offered. High density of localized screw dislocations by deformation form the dense spiral steps of atomic scale on Sn surface. The spiral steps would induce the nucleation of Sn whisker. Edge dislocations localized at the same region where dense screw dislocations exist supply Sn atoms to the Sn whisker through pipe diffusion. Both screw and edge dislocations would bend along almost one direction, namely, to relax the external shear stress. The image force also helps to bend the dislocations perpendicular to the whisker side-surface. The bending of dislocations at root of whisker leads the bend of whisker. The pipe diffusion of Sn atoms through edge dislocations from bulk Sn toward whisker is suppressed at the bent part of edge dislocation, resulting in release of Sn atoms inside whisker and leading to the growth of whisker near its root.

  18. A model for nucleation of tin whisker through dislocation behavior

    A model for the nucleation and growth processes of Sn whisker is offered. High density of localized screw dislocations by deformation form the dense spiral steps of atomic scale on Sn surface. The spiral steps would induce the nucleation of Sn whisker. Edge dislocations localized at the same region where dense screw dislocations exist supply Sn atoms to the Sn whisker through pipe diffusion. Both screw and edge dislocations would bend along almost one direction, namely, to relax the external shear stress. The image force also helps to bend the dislocations perpendicular to the whisker side-surface. The bending of dislocations at root of whisker leads the bend of whisker. The pipe diffusion of Sn atoms through edge dislocations from bulk Sn toward whisker is suppressed at the bent part of edge dislocation, resulting in release of Sn atoms inside whisker and leading to the growth of whisker near its root.

  19. Level set simulation of dislocation dynamics in thin films

    Quek, S.S. [Institute of High Performance Computing, 1 Science Park Road, 01-01, The Capricorn, Singapore Science Park II, Singapore 117528 (Singapore)]. E-mail: quekss@ihpc.a-star.edu.sg; Xiang, Y. [Department of Mathematics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Zhang, Y.W. [Department of Materials Science and Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260 (Singapore); Srolovitz, D.J. [Princeton Materials Institute and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Lu, C. [Institute of High Performance Computing, 1 Science Park Road, 01-01, The Capricorn, Singapore Science Park II, Singapore 117528 (Singapore)

    2006-05-15

    We develop a level set method-based, three-dimensional dislocation dynamics simulation method to describe the motion of dislocations in a heteroepitaxial thin film. The simulations accurately describe the elastic interactions of the dislocations, stress fields throughout the film and substrate, dislocation annihilation, and dislocation reactions. As an example application, we consider the expansion of dislocation half-loops in a Si{sub 1-{eta}}Ge{sub {eta}} thin film on a Si substrate. The expansion of the loop(s) creates interfacial misfit dislocations connected to propagating threading segments. The simulations show cross-slip of screw segments from one (1 1 1) glide plane to another, topological changes, and thermodynamically favorable dislocation reactions.

  20. Continuum dislocation dynamics: Towards a physical theory of crystal plasticity

    Hochrainer, Thomas; Sandfeld, Stefan; Zaiser, Michael; Gumbsch, Peter

    2014-02-01

    The plastic deformation of metals is the result of the motion and interaction of dislocations, line defects of the crystalline structure. Continuum models of plasticity, however, remain largely phenomenological to date, usually do not consider dislocation motion, and fail when materials behavior becomes size dependent. In this work we present a novel plasticity theory based on systematic physical averages of the kinematics and dynamics of dislocation systems. We demonstrate that this theory can predict microstructure evolution and size effects in accordance with experiments and discrete dislocation simulations. The theory is based on only four internal variables per slip system and features physical boundary conditions, dislocation pile ups, dislocation curvature, dislocation multiplication and dislocation loss. The presented theory therefore marks a major step towards a physically based theory of crystal plasticity.

  1. Acute Concomitant Anterior Cruciate Ligament and Patellar Tendon Tears in a Non-dislocated Knee

    Robert D Wissman

    2012-01-01

    Full Text Available Anterior cruciate ligament (ACL tears are common and may occur in isolation or with other internal derangements of the joint. Tears of the patellar tendon (PT occur less frequently and are rarely associated with intra-articular pathology. Acute combined tears of both the ACL and PT are known complications of high-energy traumatic knee dislocations. We present a case of an acute concomitant ACL and PT tears in a low-energy non-dislocated knee. To our knowledge, this injury has only been described in a limited number of case reports in the orthopedic literature. We present the imaging findings of this combined injury and discuss the importance of magnetic resonance (MR in diagnosis.

  2. Sidewall penetration of dislocations in ion-implanted bipolar transistors

    Phosphorus-doped emitters have been formed by either conventional diffusion or implantation, anneal, and drive-in processes. Transmission electron microscopy and measurements of transistor characteristics were made to evaluate the two processes. Comparison of structures with similar dislocation densities indicated that the dislocations in the implanted structures penetrated the emitter-base sidewall, whereas the dislocations in the diffused structure were confined to the emitter region. The transistor with extended dislocations exhibited high leakage current and excess popcorn noise generating

  3. Bilateral posterior shoulder dislocation after electrical shock: A case report

    Ismail Emre Ketenci; Tahir Mutlu Duymus; Ayhan Ulusoy; Hakan Serhat Yanik; Serhat Mutlu; Mehmet Oguz Durakbasa

    2015-01-01

    Introduction: Posterior dislocation of the shoulder is a rare and commonly missed injury. Unilateral dislocations occur mostly due to trauma. Bilateral posterior shoulder dislocations are even more rare and result mainly from epileptic seizures. Electrical injury is a rare cause of posterior shoulder dislocation. Injury mechanism in electrical injury is similar to epileptic seizures, where the shoulder is forced to internal rotation, flexion and adduction. Presentation of case: This report...

  4. Midterm results after operatively stabilised shoulder dislocations in elderly patients

    Maier, Marcus; Geiger, Emanuel V.; Ilius, Christine; FRANK, JOHANNES; Marzi, Ingo

    2008-01-01

    Anterior shoulder dislocation is frequently seen in young patients. The therapeutic regime in elderly patients after shoulder dislocation is less clearly defined. The aim of this study was to compare the clinical benefit of operative stabilisation following anterior shoulder dislocation in young versus elderly patients. Seventy-two patients with anterior shoulder dislocations were allocated into two groups. Group 1 (> 40 years of age) consisted of 23 patients, and group 2 (

  5. A Case of Simultaneous Bilateral Anterior Shoulder Dislocation

    Patil, Mallanagouda N

    2013-01-01

    Introduction: Anterior dislocation of shoulder is commonest dislocation one encounters in day to day Orthopaedic practice. But bilateral shoulder dislocations are relatively uncommon frequently posterior and secondary to violent muscle contraction. Simultaneous bilateral anterior dislocations of shoulder following trauma is rare occurrence. Case Report: 35 year old male presented to emergency department with history fall by tripping on a stone (fall on outstretched hand). He complained of...

  6. Dislocation dynamics in Rayleigh-Bénard convection.

    Walter, Th; Pesch, W; Bodenschatz, E

    2004-09-01

    Theoretical results on the dynamics of dislocations in Rayleigh-Bénard convection are reported both for a Swift-Hohenberg model and the Oberbeck-Boussinesq equations. For intermediate Prandtl numbers the motion of dislocations is found to be driven by the superposition of two independent contributions: (i) the Peach-Koehler force and (ii) an advection force on the dislocation core by its self-generated mean flow. Their competition allows to explain the experimentally observed bound dislocation pairs. PMID:15447003

  7. Cervical facet dislocation adjacent to the fused motion segment

    Kunio Yokoyama

    2016-01-01

    Full Text Available This study reports on a case that forces re-examination of merits and demerits of anterior cervical fusion. A 79-year-old male was brought to the emergency room (ER of our hospital after he fell and struck the occipital region of his head following excessive alcohol consumption. Four years prior, he had undergone anterior cervical discectomy and fusion of C5/6 and a magnetic resonance imaging (MRI performed 3 years after this surgery indicated that he was suffering from degeneration of C6/7 intervertebral discs. After arriving at the ER, he presented motor impairment at level C7 and lower of manual muscle testing grade 1 as well as moderate loss of physical sensation from the trunk and peripheries of both upper limbs to the peripheries of both lower limbs (Frankel B. Cervical computed tomography (CT indicated anterior dislocation of C6/7, and MRI indicated severe spinal cord edema. We performed manipulative reduction of C6/7 with the patient under general anesthesia. Next, we performed laminectomy on C5-T1 and posterior fusion on C6/7. Postoperative CT indicated that cervical alignment had improved, and MRI indicated that the spinal cord edema observed prior to surgery had been mitigated. Three months after surgery, motor function and sensory impairment of the lower limbs had improved, and the patient was ambulatory upon discharge from the hospital (Frankel D. In the present case, although C5 and 6 were rigidly fused, degeneration of the C6/7 intervertebral disc occurred and stability was compromised. As a result, even slight trauma placed a severe dynamic burden on the facet joint of C6/7, which led to dislocation.

  8. Cervical facet dislocation adjacent to the fused motion segment.

    Yokoyama, Kunio; Kawanishi, Masahiro; Yamada, Makoto; Tanaka, Hidekazu; Ito, Yutaka; Kuroiwa, Toshihiko

    2016-01-01

    This study reports on a case that forces re-examination of merits and demerits of anterior cervical fusion. A 79-year-old male was brought to the emergency room (ER) of our hospital after he fell and struck the occipital region of his head following excessive alcohol consumption. Four years prior, he had undergone anterior cervical discectomy and fusion of C5/6 and a magnetic resonance imaging (MRI) performed 3 years after this surgery indicated that he was suffering from degeneration of C6/7 intervertebral discs. After arriving at the ER, he presented motor impairment at level C7 and lower of manual muscle testing grade 1 as well as moderate loss of physical sensation from the trunk and peripheries of both upper limbs to the peripheries of both lower limbs (Frankel B). Cervical computed tomography (CT) indicated anterior dislocation of C6/7, and MRI indicated severe spinal cord edema. We performed manipulative reduction of C6/7 with the patient under general anesthesia. Next, we performed laminectomy on C5-T1 and posterior fusion on C6/7. Postoperative CT indicated that cervical alignment had improved, and MRI indicated that the spinal cord edema observed prior to surgery had been mitigated. Three months after surgery, motor function and sensory impairment of the lower limbs had improved, and the patient was ambulatory upon discharge from the hospital (Frankel D). In the present case, although C5 and 6 were rigidly fused, degeneration of the C6/7 intervertebral disc occurred and stability was compromised. As a result, even slight trauma placed a severe dynamic burden on the facet joint of C6/7, which led to dislocation. PMID:26933361

  9. Cervical facet dislocation adjacent to the fused motion segment

    Yokoyama, Kunio; Kawanishi, Masahiro; Yamada, Makoto; Tanaka, Hidekazu; Ito, Yutaka; Kuroiwa, Toshihiko

    2016-01-01

    This study reports on a case that forces re-examination of merits and demerits of anterior cervical fusion. A 79-year-old male was brought to the emergency room (ER) of our hospital after he fell and struck the occipital region of his head following excessive alcohol consumption. Four years prior, he had undergone anterior cervical discectomy and fusion of C5/6 and a magnetic resonance imaging (MRI) performed 3 years after this surgery indicated that he was suffering from degeneration of C6/7 intervertebral discs. After arriving at the ER, he presented motor impairment at level C7 and lower of manual muscle testing grade 1 as well as moderate loss of physical sensation from the trunk and peripheries of both upper limbs to the peripheries of both lower limbs (Frankel B). Cervical computed tomography (CT) indicated anterior dislocation of C6/7, and MRI indicated severe spinal cord edema. We performed manipulative reduction of C6/7 with the patient under general anesthesia. Next, we performed laminectomy on C5-T1 and posterior fusion on C6/7. Postoperative CT indicated that cervical alignment had improved, and MRI indicated that the spinal cord edema observed prior to surgery had been mitigated. Three months after surgery, motor function and sensory impairment of the lower limbs had improved, and the patient was ambulatory upon discharge from the hospital (Frankel D). In the present case, although C5 and 6 were rigidly fused, degeneration of the C6/7 intervertebral disc occurred and stability was compromised. As a result, even slight trauma placed a severe dynamic burden on the facet joint of C6/7, which led to dislocation. PMID:26933361

  10. On onsagers principle, dislocation motion and hydrogen embrittlement

    Louthan, M. R., Jr.; Mcnitt, R. P.

    1976-01-01

    Onsager's reciprocal relationships from the linear theory of irreversible thermodynamics are applied to hydrogen - dislocation interactions. Existing experimental evidence shows that dislocation motion causes localized hydrogen accumulation; thus, from the Onsager principle, localized hydrogen accumulations will affect dislocation motion and therefore the properties of metals and alloys exposed to hydrogen environments.

  11. Bypassing of a barrier by dissociated and superlattice dislocations

    Bhushan, Karihaloo

    1975-01-01

    Very simple procedures are used to calculate the upper and lower bounds for the applied stress required for the leading extended (superlattice) dislocation in a group of n coplanar screw dislocations of like sign with Burgers vector b to bypass a noncoplanar perfect screw dislocation with Burgers...... vector mb (m...

  12. Kinetics of dislocation step ensembles and edge dislocation climb in supersaturated solution of radiation-induced point defects

    Formation kinetics of step ensemble on the linear edge dislocation under conditions when supersaturated solution of radiation-induced point defects - vacancies and interstitials - was created in a material inder the effect of irradiation, is investigated. With regard to microscopic processes in dislocation nuclei the concentration of steps on the dislocation is found in a self-consistent way. Conditions under which the dislocations can be considered as discrete discharges for point defects so that the distance between dislocation steps exceeds considerably the average length of point defect free pass along the dislocation line are determined. The dislocation climb rate for the cases of material irradiation and annealing, which are of practical value, is found. Considerably nonlinear dependence of the dislocation climb rate on point defect supersaturation in material and its strong dependence on the temperature is demonstrated

  13. Assessment of hardening due to dislocation loops in bcc iron: Overview and analysis of atomistic simulations for edge dislocations

    Bonny, G.; Terentyev, D.; Elena, J.; Zinovev, A.; Minov, B.; Zhurkin, E. E.

    2016-05-01

    Upon irradiation, iron based steels used for nuclear applications contain dislocation loops of both and ½ type. Both types of loops are known to contribute to the radiation hardening and embrittlement of steels. In the literature many molecular dynamics works studying the interaction of dislocations with dislocation loops are available. Recently, based on such studies, a thermo-mechanical model to threat the dislocation - dislocation loop (DL) interaction within a discrete dislocation dynamics framework was developed for ½ loops. In this work, we make a literature review of the dislocation - DL interaction in bcc iron. We also perform molecular dynamics simulations to derive the stress-energy function for loops. As a result we deliver the function of the activation energy versus activation stress for loops that can be applied in a discrete dislocation dynamics framework.

  14. Causal Stroh formalism for uniformly-moving dislocations in anisotropic media: Somigliana dislocations and Mach cones

    Pellegrini, Yves-Patrick

    2016-01-01

    In this work, Stroh's formalism is endowed with causal properties on the basis of an analysis of the radiation condition in the Green tensor of the elastodynamic wave equation. The modified formalism is applied to dislocations moving uniformly in an anisotropic medium. In practice, accounting for causality amounts to a simple analytic continuation procedure whereby to the dislocation velocity is added an infinitesimal positive imaginary part. This device allows for a straightforward computation of velocity-dependent field expressions that are valid whatever the dislocation velocity ---including supersonic regimes--- without needing to consider subsonic and supersonic cases separately. As an illustration, the distortion field of a Somigliana dislocation of the Peierls-Nabarro-Eshelby-type with finite-width core is computed analytically, starting from the Green tensor of elastodynamics. To obtain the result in the form of a single compact expression, use of the modified Stroh formalism requires splitting the Gr...

  15. Missed isolated volar dislocation of the scaphoid

    Kolby, Lise; Larsen, Søren; Jørring, Stig; Sørensen, Allan Ibsen; Leicht, Pernille

    2007-01-01

    A patient presented with volar dislocation of the scaphoid, the diagnosis of which had been missed for two weeks. He was treated with open reduction through a combined volar and dorsal approach with decompression of the median nerve, internal fixation, and a cast for eight weeks. One year postope...

  16. [Open total dislocation of the talus].

    Grabski, R S; Sosiński, R

    1992-01-01

    A case of 35 years old patient with open, total, fixed dislocation of the talus reduced with heel traction is presented. The Sudeck syndrome subsided after one year. Weight bearing was not allowed for 7 months. An examination after 2.5 years revealed minor osteoarthritis, full range of movement in the foot but limited walking capability. PMID:7555299

  17. Completion of a Dislocated Metric Space

    P. Sumati Kumari

    2015-01-01

    Full Text Available We provide a construction for the completion of a dislocated metric space (abbreviated d-metric space; we also prove that the completion of the metric associated with a d-metric coincides with the metric associated with the completion of the d-metric.

  18. Screening for congenital dislocation of the hip

    Although the prevalence of (idiopathic) congenital dislocation of the hip (CDH) within the Member States of the European Community is not exactly known, it must be considered as a major problem of public health care and protection. By assessment of available data one can assume that between 1 and 2% of all newborns have dislocation or instability of one or both hips. There is a female predominance of 4:1 and some risk factors are known. The reasons of a higher prevalence in some areas are not yet well understood. Most of instable hips will spontaneously become stable within the first days or weeks of life. However, a considerable number of infants (less than 1%) will remain with instable hips which may dislocate. Dislocation either present at birth or as a result of persistent instability leads to subsequent hip deformation. This is a serious event for each affected individual, and is a heavy load on health care and social costs for the public. Treatment of CDH is easy and usually effective when started early, i.e. before the fourth month of life. The earlier treatment is started the easier, shorter, safer and less expensive it is and its impairment on child development and mother-child interaction can be held to a minimum. Screening for CDH is therefore the most important part of health protection in early infancy. However, this paper concludes that neither sonography nor X-ray examinations are appropriate for CDH screening

  19. Dislocation nucleation and multiplication during nanoindentation testing

    Small volumes of crystalline material can exhibit near theoretical lattice strengths due to the absence of pre-existing defects. The authors show here that careful control of experimental parameters and surface preparation are important in observing these increased stresses. In particular, tip impact kinetic energies at the initial contact of only a few eV have been found to influence events occurring at a much later stage in the loading cycle. This can be understood in terms of the energy required to deform a small number of atomic scale asperities and thus release sufficient surface energy to permit dislocation nucleation at impact. If the K.E. is not sufficient to overcome the asperities, dislocations must be nucleated at a later stage in the loading cycle, giving an apparently different mechanical property. The authors outline the implications for thin film systems where a hard surface layer may play a vital role, firstly, in preventing dislocation nucleation on impact and, secondly, in impeding the propagation of any such dislocations into the bulk below

  20. Dislocation Microstructures in Fatiqued Copper Polycrystals

    Winter, A.T.; Pedersen, Ole Bøcker; Rasmussen, K.V.

    1981-01-01

    Dislocation structures characteristic of persistent slip bands were observed in the interior of polycrystalline copper after fatigue. At low strain amplitudes, within the plateau on the cyclic stress-strain curve, only structures identical to those seen in single crystals were observed. This allo...

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

    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.

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

    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.

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

    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

  4. Screw dislocation in hcp Ti : DFT dislocation excess energies and metastable core structures

    An extensive DFT search of (meta)stable structures of the (a/3)〈1 1 2-bar 0〉 screw dislocation in hcp-Ti is presented. It reveals that the stable core structures are never basal but always prismatic. This prismatic core dissociates into two partial dislocations in the same or neighboring prismatic planes depending on the initial position of the dislocation line, leading to either a symmetric or an asymmetric core. An alternative way of defining the core region from an electronic structure point of view is also proposed. It evidences clearly the symmetric or asymmetric character of the cores. We then introduce an ansatz for a straightforward and fast calculation of the excess energy, per unit length of dislocation, of a screw dislocation applicable to DFT calculations, in the cluster approach. The method is first validated on calculations of a (a/3)〈1 1 2-bar 0〉 screw dislocation in hcp-Ti, performed with an EAM potential from which exact excess energies can be extracted. Then, it is shown that it does work in a DFT calculation, through its application to the same screw dislocation in hcp-Ti with an accuracy of 8.4 meV/Å (1.8% of the excess energy for a cluster of 126 atoms per plane normal to the dislocation line). The comparison of the excess energies of the symmetric and assymmetric cores, calculated with the proposed ansatz, reveals that their energy difference is within the uncertainty of the method, which implies that the potential energy surface is very flat and that there could be many metastable core structures in hcp-Ti. (paper)

  5. The gauge theory of dislocations: static solutions of screw and edge dislocations

    Lazar, Markus; Anastassiadis, Charalampos

    2009-01-01

    Abstract We investigate the T(3)-gauge theory of static dislocations in continuous solids. We use the most general linear constitutive relations bilinear in the elastic distortion tensor and dislocation density tensor for the force and pseudomoment stresses of an isotropic solid. The constitutive relations contain six material parameters. In this theory both the force and pseudomoment stresses are asymmetric. The theory possesses four characteristic lengths ...

  6. Closed reduction of displaced or dislocated mandibular condyle fractures in children using threaded Kirschner wire and external rubber traction.

    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. PMID:26117724

  7. Transfer of molecular dynamics data to dislocation dynamics to assess dislocation–dislocation loop interaction in iron

    We propose a computationally fast and physically justifiable method to treat dislocation loops as stochastic thermally activated finite-size obstacles in discrete dislocation dynamics simulations. The method was parameterized using molecular dynamics data for the interaction of dislocations with a0/2〈1 1 1〉 dislocation loops. As demonstration, the method is applied to rationalize experimental hardening of neutron-irradiated iron. The obtained results show good agreement with experimental data

  8. Benign Joint Hypermobility Syndrome – not so ‘Benign’

    Yathish GC

    2015-05-01

    Full Text Available Benign joint hypermobility syndrome (BJHS was earlier considered as a mild or trivial entity, but nowadays it is reported as a multisystem hereditary connective tissue disorder with serious morbidities. In fact, the term ‘Benign’ has been removed, renaming the disease as ‘Joint Hypermobility Syndrome’ (JHS. In addition to the well-known musculoskeletal consequences of joint pain and instability, it can cause chronic widespread pain, gastrointestinal dysmotility, anxiety, phobic states and dysautonomia. We present here the case of a 53-year-old lady who presented with history of irritable bowel syndrome, elbow dislocation, repeated knee injuries, and instability resulting in severe secondary osteoarthritis (OA.

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

    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 χ 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

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

    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.

  11. Proximal tibiofibular joint: Rendezvous with a forgotten articulation

    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.

  12. Proximal tibiofibular joint: Rendezvous with a forgotten articulation.

    Sarma, Amitav; Borgohain, Bhaskar; Saikia, Bishwajeet

    2015-01-01

    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. PMID:26538753

  13. Dislocation dynamics. II. Applications to the formation of persistent slip bands, planar arrays, and dislocation cells

    The dynamic organization of dislocations into spatially heterogeneous substructures is demonstrated by applying the principles of dislocation dynamics that were outlined in the preceding paper. Here it is shown that the formation of persistent slip bands is a consequence of the competition between dipole formation and annihilation of dislocations of opposite Burgers vectors in the absence of temperature-enhanced climb recovery under cyclic stress conditions. Planar arrays, which are also uniaxial structures, are shown to arise from enhanced dislocation multiplication and the formation of stable dipole configurations along a slip plane at lower temperatures where climb is unimportant. Biaxial dislocation systems experience additional degrees of freedom compared with uniaxial systems because of available motion along additional slip systems. It is demonstrated that for a system of orthogonal slip directions at high temperatures in which climb and glide motion are competitive, dislocation cellular structures form as a result of immobile dipole and junction formation and by the internal elastic strain energy minimization caused by long-range self-shielding. It is shown that the internal elastic strain energy is reduced by the self-organization process. However, the short-range nonlinear processes (i.e., dipole and junction formation) are shown not to allow absolute elastic energy minimization

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

    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

  15. Photoluminescence of Dislocations in Nitrogen Doped Czochralski Silicon

    LI Dong-Sheng; YANG De-Ren; E.Leoni; S.Binetti; S.Pizzini

    2004-01-01

    @@ We investigate optical properties of dislocations in nitrogen-doped and nitrogen-free Czochralski silicon. The dislocations are formed during crystal growth, but not formed during deformation. The results show that in nitrogen-doped samples, a broad band replaced the D1 band of dislocation, regardless of dislocation density. The replacement ofD1 band is caused by the non-irradiation combination induced by oxygen precipitation. Moreover,a new emission at 0.975 eV is observed in both the nitrogen-free and doped samples when the dislocation density is lower than 104 cm-2.

  16. Disorientations in dislocation structures: Formation and spatial correlation

    Pantleon, W.

    2002-01-01

    activation of slip systems on both sides of geometrically necessary boundaries. On the basis of these mechanisms, the occurrence of disorientations across both types of dislocation boundaries is modeled by dislocation dynamics. The resulting evolution of the disorientation angles with strain is in good......During plastic deformation, dislocation boundaries are formed and orientation differences across them arise. Two different causes lead to the formation of two kinds of deformation-induced boundaries: a statistical trapping of dislocations in incidental dislocation boundaries and a difference in the...

  17. Observation of Dislocation Dynamics in the Electron Microscope

    Lagow, B W; Robertson, I M; Jouiad, M; Lassila, D H; Lee, T C; Birnbaum, H K

    2001-08-21

    Deformation experiments performed in-situ in the transmission electron microscope have led to an increased understanding of dislocation dynamics. To illustrate the capability of this technique two examples will be presented. In the first example, the processes of work hardening in Mo at room temperature will be presented. These studies have improved our understanding of dislocation mobility, dislocation generation, and dislocation-obstacle interactions. In the second example, the interaction of matrix dislocations with grain boundaries will be described. From such studies predictive criteria for slip transfer through grain boundaries have been developed.

  18. Joint imaging

    Joint imaging is a proven diagnostic procedure which has become indispensable to the detection and treatment of different joint diseases in almost all disciplines. The method is suited for early diagnosis of joint affections both in soft tissue and bone which cannot be detected by X-ray or other procedures. The local activity accumulation depends on the rate of metabolism and is visualized in the scan, which in turn enables the extension and floridity of focal lesions to be evaluated and followed-up. Although joint scans may often give hints to probabilities relevant to differential diagnosis, the method is non-specific and only useful if based on the underlying clinical picture and X-ray finding, if possible. The radiation exposure is very low and does not represent a hazard in cases of adequate assessment of indication. In pregnant women and children the assessment of indication has to be based on very strict principles. The method is suited for out-patient diagnosis and can be applied in all installations equipped with a gamma camera and a technetium generator. (orig.)

  19. Thermally activated dislocation motion including inertial effects in solid solutions

    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

  20. The role of reduction and internal fixation of Lisfranc fracture–dislocations: a systematic review of the literature

    Stavlas, Panagiotis; Roberts, Craig S.; Xypnitos, Fragiskos N; Giannoudis, Peter V.

    2010-01-01

    A systematic review of the literature was performed in order to evaluate the role of reduction and internal fixation in the management of Lisfranc joint fracture–dislocations. Articles were extracted from the Pubmed database and the retrieved reports were included in the study only if pre-specified eligibility criteria were fulfilled. Eleven articles were eligible for the final analysis, reporting data for the management of 257 patients. Injuries of the first three metatarsal rays were treate...