1. At an operation for recurrent posterior dislocation of the shoulder observations were made on the mechanism, head defect, method of reduction, and the position of greatest stability. 2. Experimentally, avulsion of the glenoid labrum in a monkey was shown to be capable of sound repair without operation. 3. In the treatment of primary posterior dislocation it is suggested that the position of abduction, lateral rotation and extension is favourable for the approximation of the stripped labrum and capsule to the glenoid rim, and for an effective buttress after cicatrisation. 4. If the risk of recurrence is to be reduced to a minimum the shoulder should be retained in the position of greatest stability for at least four weeks, to allow firm union of the avulsed soft tissues. 5. This position for an optimum buttress would also apply after surgical repair for recurrent posterior dislocation

1. Six cases of posterior dislocation of the shoulder are described. 2. In four cases the diagnosis was made on clinical grounds. 3. The important clinical signs are the adducted and medially rotated position of the arm, a hard mass posteriorly below the acromion representing the displaced humeral head, and limitation of movement, especially abduction and lateral rotation. 4. In two cases the dislocation was not recognised at the first examination. This confirms the statement of previous authors that posterior dislocation is easily missed. 5. The value of the vertical projection in the radiography of suspected posterior dislocation is emphasised. 6. Reduction was accomplished without difficulty in five cases and the subsequent progress of these was uneventful. In the remaining case reduction was difficult and unstable, and the final recovery incomplete. It is considered that this patient would have been better treated by early open reduction

Traumatic posterior dislocation of the hip associated with a fracture of the posterior acetabular wall and of the neck of the femur is a rare injury. A 29-year-old man presented at a level 1 trauma centre with a locked posterior dislocation of the right hip, with fractures of the femoral neck and the posterior wall of the acetabulum after a bicycle accident. An attempted closed reduction had failed. This case report describes in detail the surgical management and the clinical and radiological outcome. Open reduction and fixation with preservation of the intact retinaculum was undertaken within five hours of injury with surgical dislocation of the hip and a trochanteric osteotomy. Two years after operation the function of the injured hip was good. Plain radiographs and MR scans showed early signs of osteoarthritis with some loss of joint space but no evidence of avascular necrosis. The patient had begun skiing and hiking again. The combination of fractures of the neck of the femur and of the posterior wall of the acetabulum hampers closed reduction of a posterior dislocation of the hip. Surgical dislocation of the hip with trochanteric flip osteotomy allows controlled open reduction of the fractures, with inspection of the hip joint and preservation of the vascular supply

Aims. The aim of this study was to identify the optimal lip position for total hip arthroplasties (THAs) using a lipped liner. There is a lack of consensus on the optimal position, with substantial variability in surgeon practice. Methods. A model of a THA was developed using a 20° lipped liner. Kinematic analyses included a physiological range of motion (ROM) analysis and a provocative dislocation manoeuvre analysis. ROM prior to impingement was calculated and, in impingement scenarios, the travel distance prior to dislocation was assessed. The combinations analyzed included nine cup positions (inclination 30-40-50°, anteversion 5-15-25°), three stem positions (anteversion 0-15-30°), and five lip orientations (right hip 7 to 11 o’clock). Results. The position of the lip changes the ROM prior to impingement, with certain combinations leading to impingement within the physiological ROM. Inferior lip positions (7 to 8 o’clock) performed best with cup inclinations of 30° and 40°. Superior lip positions performed best with cup inclination of 50°. When impingement occurs in the plane of the lip, the lip increases the travel distance prior to dislocation. Inferior lip positions led to the largest increase in jump distance in a posterior dislocation provocation manoeuvre. Conclusion. The lip orientation that provides optimal physiological ROM depends on the orientation of the cup and stem. For a THA with stem anteversion 15°, cup inclination 40°, and cup anteversion 15°, the optimal lip position was posterior-inferior (8 o’clock). Maximizing jump distance prior to dislocation while preventing impingement in the opposite direction is possible with appropriate lip positioning. Cite this article: Bone Joint Res 2023;12(9):571–579

The treatment of a chronic posterior dislocation of the shoulder is often determined by the size of the associated impression fracture of the humeral head. Our hypothesis was that patients with a chronic unreduced posterior dislocation of the shoulder and a defect in the humeral head involving between 25% to 50% of the articular surface, would do better if reconstructed with an allograft from the femoral head rather than treated by a non-anatomical reconstruction. We reviewed ten men and three women with a mean age of 42 years (36 to 51) at a mean follow-up of 54 months (41 to 64) who had this procedure. At follow-up, nine had no pain or restriction of activities of daily living. Their mean Constant-Murley shoulder score was 86.8 (43 to 98). No patient had symptoms of instability of the shoulder. Reconstruction of the defect in the humeral head with an allograft provides good pain relief, stability and function for patients with a locked, chronic posterior dislocation where the defect involves between 25% and 50% of the circumference of the articular surface

A man of 52 years of age had a grand mal seizure. He presented to our unit three months later with irreducible bilateral posterior dislocation of the shoulder. CT scans revealed large compression defects on the anteromedial aspect of the heads of both humeri. The defect on the right side was of more than 50% of the articular surface, and on the left side of 40%. He was treated by a one-stage operation with a hemiarthroplasty on one side and reconstruction of the head by an osteochondral autograft on the other. Three years later the clinical and radiological results were excellent

1. A case of posterior dislocation of both shoulders, in a patient believed to be epileptic, is described. 2. The difficulties of early diagnosis are discussed

We describe two boys with bilateral deformity of the upper end of the radius. The condition appears to predispose to non-traumatic posterior dislocation of the radial head and is associated with posterior bowing of the upper end of the ulna. This problem has not been previously described

Twenty-three patients, aged from 10 to 60 years, underwent open reduction for untreated posterior dislocations of the elbow. The dislocations had been unreduced for periods varying from one month to two years. All patients underwent a standard procedure based on the Speed technique. Complications after operation included one case of gross sepsis and five cases of ulnar neuritis. Most patients gained a useful range of flexion-extension of the elbow. Neither the age of the patient nor the duration of the unreduced dislocation influenced the result

Posterior dislocation of the shoulder is an unusual injury and there is often much delay before the diagnosis is made. Nevertheless, if the condition is borne in mind when examining the patient and studying the X-ray films the diagnosis should not be missed. A single antero-posterior radiograph of the shoulder joint is inadequate. For the radiologist a pair of stereoscopic films is desirable; but for routine emergency work in hospital other projections are necessary. A vertical view should be taken, either with the limb abducted and the tube in the axilla, or with the tube above the shoulder and a curved cassette in the axilla. When this is impossible a profile or posterior oblique view of the scapula may be substituted

1. A review of fifty-eight posterior dislocations or fracture-dislocations of the hip is presented. 2. With few exceptions, patients were treated by immediate reduction of the dislocation under general anaesthesia, traction for six weeks and avoidance of weight-bearing for a further six weeks. 3. The results are discussed with reference to the age of the patient, length of follow-up, side affected and type of dislocation. 4. As a result ofthis review, we propose to reduce the period oftreatment in Type I dislocations (posterior dislocation without fracture) and to continue a conservative policy in respect to treatment and reconstructive hip surgery in Types II and HI fracture-dislocations

A case of simultaneous posterior dislocation of both shoulders, occurring in an epileptiform fit, is described. Manipulative reduction succeeded after five days, and full function was gained

The factors involved in the mechanism leading to traumatic posterior dislocation of the hip are examined. In 47 adult patients who had previously suffered such a dislocation, ultrasound scans were used to measure femoral anteversion on both the affected and the uninjured side. In 36 normal adult volunteers, used as controls, similar measurements were made. Femoral anteversion on both the injured and uninjured side was significantly reduced in the patients compared with the volunteers. These findings are discussed in the light of previous work which indicates that medial rotation is a factor in the mechanism of posterior dislocation of the hip. It is suggested that reduced anteversion acts like medial rotation to make the hip more susceptible to posterior dislocation, and that the less the anteversion the more likely is the injury to be a dislocation rather than a fracture-dislocation. It is concluded that patients who suffer such dislocated hips belong at one extreme of the normal population, having either reduced femoral anteversion or even retroversion, and that this anatomical feature selects towards hip dislocation rather than to injury of the femoral shaft, knee or tibia during the appropriate type of accident

A new technique for repair of neglected posterior dislocation of the elbow is described, consisting of open reduction with tendon graft stabilisation to create a medial collateral and an intra-articular "cruciate" ligament. This allows flexion-extension exercises to start six days after operation. Eleven cases are reported in which the average range of movement improved from 38 degrees before operation to 105 degrees after a minimum follow-up of two years, with a mean valgus-varus instability of only 13 degrees. One patient had a postoperative infection but all the others were satisfied with the functional result

Out of a total of 91 patients with traumatic posterior dislocation of the hip treated between 1936 and 1974 in the Mansfield area, 81 patients were reviewed. The average follow-up period was 12.5 years, although there was a large number of cases with a follow-up of more than 15 years and a smaller number with a follow-up of 30 years. The overall results were surprisingly poor despite early reduction of the dislocation in the majority of cases. We found that 15 years after simple dislocation 24 per cent of the cases had a poor result by both clinical and radiological criteria, but in the more severe grades of initial injury the results became worse, with 73.3 per cent of the patients graded as fair and poor, and only 26.7 per cent graded excellent or good

We aimed to identify variables associated with clinical and radiological outcome following fractures of the acetabulum associated with posterior dislocation of the hip. Using a prospective database of 1076 such fractures, we identified 109 patients with this combined injury managed operatively within three weeks and followed up for two or more years. The patients had a mean age of 42 years (15 to 79), 78 (72%) were male, and 84 (77%) had been involved in motor vehicle accidents. Using multivariate analysis the quality of reduction of the fracture was identified as the only significant predictor of radiological grade, clinical function and the development of post-traumatic arthritis (p < 0.001). All patients lacking anatomical reduction developed arthritis whereas only 25.5% (24 patients) with an anatomical reduction did so (p = 0.05). The quality of the reduction of the fracture is the most important variable in forecasting the outcome for patients with this injury. The interval to reduction of the dislocation of the hip may be less important than previously described

Four cases of posterior dislocation of the shoulder at birth in association with obstetric brachial plexus palsy are presented. Review of the literature suggests that this association is not generally recognised. All cases were diagnosed late; two were treated by open reduction, one by humeral osteotomy and one managed conservatively

Four cases of arterial damage resulting from closed posterior dislocation of the elbow are described. Two of these have been successfully treated by conservative methods and two by vein graft to the damaged artery. Sixteen previous cases are detailed and the management of this uncommon complication of dislocated elbow is discussed

Four patients who had injured the lower end of the humerus in childhood with resulting cubitus varus developed recurrent posterior dislocation of the head of the radius after further injury to the elbow. Dislocation occurred when the forearm was supinated and spontaneous reduction took place on pronation. At operation the lateral ligament complex was seen to be lax and elongated. After tightening of the ligament and with a supracondylar osteotomy of the humerus to correct the cubitus varus the recurrent dislocation was eliminated

1 . A case of posterior dislocation of the shoulder treated by open reduction and obliteration of the defect in the head of the humerus by implantation of the subscapularis tendon is reported. 2. It is suggested that this method is indicated in cases in which there is a deep V-shaped depression on the anterior aspect of the humeral head