1. Isolated dislocation of the radius at the elbow occurs most commonly as a pronation injury, associated with slight elbow flexion and a varus strain. Disruption of the radio-ulnar articulation occurs primarily because of tearing of the annular ligament, which is the most important reinforcing structure of this joint. The tensing of the interosseous membrane through neutral into supination, and consequently the approximation of the radius to ulna, supports the recognised supination manoeuvre to reduce such an injury. 2. It is suggested that this injury may be more common than previously appreciated. It may be not diagnosed, it may be over-diagnosed as total dislocation of the elbow, or it may be belatedly diagnosed as a congenital dislocation of the radial head

1. A collected series of forty-seven traumatic dislocations of the hip in children is reported and reviewed in detail. 2. All were simple hip dislocations, and no child was included in whom there was any other injury to the affected joint. 3. All were posterior dislocations. 4. No anatomical predisposition was observed. 5. Significant complications occurred in fourteen children: avascular necrosis of the head of the femur in four, degenerative joint changes in three, premature epiphysial fusion in one and overgrowth of the femoral head in six. Study of the children with these complications revealed no common cause except the dislocation itself. 6. The injury responsible was often trivial. 7. The results suggest that it is harmless to bear weight four weeks after reduction

To determine the natural history of dislocation of the hip in cerebral palsy, and to evolve methods to predict dislocation, the notes and radiographs of 462 patients with cerebral palsy were reviewed. Dislocation occurred in 10% of patients by progressive migration and subluxation of the proximal femur in the presence of acetabular dysplasia. Statistical analysis identified the radiographic features that helped to predict dislocation. Measurement of acetabular index, by a method that allows for rotation of the acetabulum, was the most powerful single predictor. Measurement of this index at two and four years of age could identify patients who would dislocate unless effective treatment was undertaken, those at risk of dislocation only if scoliosis developed, and those who would not dislocate. On the basis of this method of screening for dislocation, a logical system of surgical prophylaxis is proposed

The femoral head receives blood supply mainly from the deep branch of the medial femoral circumflex artery (MFCA). In previous studies we have performed anatomical dissections of 16 specimens and subsequently visualised the arteries supplying the femoral head in 55 healthy individuals. In this further radiological study we compared the arterial supply of the femoral head in 35 patients (34 men and one woman, mean age 37.1 years (16 to 64)) with a fracture/dislocation of the hip with a historical control group of 55 hips. Using CT angiography, we identified the three main arteries supplying the femoral head: the deep branch and the postero-inferior nutrient artery both arising from the MFCA, and the piriformis branch of the inferior gluteal artery. It was possible to visualise changes in blood flow after fracture/dislocation. Our results suggest that blood flow is present after reduction of the dislocated hip. The deep branch of the MFCA was patent and contrast-enhanced in 32 patients, and the diameter of this branch was significantly larger in the fracture/dislocation group than in the control group (p = 0.022). In a subgroup of ten patients with avascular necrosis (AVN) of the femoral head, we found a contrast-enhanced deep branch of the MFCA in eight hips. Two patients with no blood flow in any of the three main arteries supplying the femoral head developed AVN. Cite this article: Bone Joint J 2013;95-B:1453–7

Subtalar dislocation is a significant injury characterised by late complications, including subtalar arthritis. We describe a rare case of irreducible posterior subtalar dislocation due to incarceration of a fracture of the anterior process of the calcaneum in the subtalar joint, and discuss appropriate management

1. The results of treatment of 134 patients with congenital dislocation of 167 hips are reviewed. 2. Late diagnosis is still a major problem. 3. Subluxations rarely give rise to poor results, but in dislocations first treated over the age of five years there is a one-in-three risk of failure. 4. Manipulative reduction is successful less often than reduction on a frame and carries a higher risk of avascular necrosis. 5. Closed reduction on a frame was satisfactory in 58 per cent of patients under the age of three years, and can succeed up to the age of five. 6. Open reduction was required in 20 per cent of cases under the age of three, and can be used successfully up to the age of six. 7. Seven anatomical barriers to closed reduction have been recognised and two or more are commonly found in one hip when open reduction is performed. 8. The acetabular roof may fail to develop after reduction, especially if this is delayed. A C.E. angle of under 20 degrees does not necessarily forebode this, unless measured on an arthrograph. Sclerosis of a sloping acetabular roof is an indication for operation. Acetabuloplasty is the proper operation for a sloping acetabulum and can be done successfully up to the age of twelve. Over this age, a shelf operation should be performed; this is appropriate also in younger patients in whom the curvature of the acetabulum is normal but does not extend far enough laterally. These operations were required in 38 per cent of hips treated in patients under the age of three, and in 64 per cent over this age. There is a one-in-three risk of avascular necrosis when acetabular reconstruction is done in patients under three. 9. Anteversion, if excessive, should be corrected by subtrochanteric osteotomy, and any valgus of the femoral neck should be corrected simultaneously. 10. Unilateral dislocations in patients over the age of six are best treated by Colonna's operation. In our few bilateral cases over this age our results have been disappointing. 11. Avascular necrosis is less common but more serious when it occurs over the age of three. Manipulative reduction and the use of frog-leg plasters are two avoidable factors which appear to increase its incidence. The more serious degrees are accompanied by stiffness of the hip, and when this sign is present weight bearing should be avoided. 12. Prolonged, though rarely permanent, limitation of movement occurs in some 10 per cent of cases. In a few, operative correction was required

We report the results at a mean of 24.3 years (20 to 32) of 61 previously reported consecutive total hip replacements carried out on 44 patients with severe congenital hip disease, performed with reconstruction of the acetabulum with an impaction grafting technique known as cotyloplasty. The mean age of the patients at operation was 46.7 years (23 to 68) and all were women. The patients were followed post-operatively for a mean of 24.3 years (20 to 32), using the Merle d’Aubigné and Postel scoring system as modified by Charnley, and with serial radiographs. At the time of the latest follow-up, 28 acetabular components had been revised because of aseptic loosening at a mean of 15.9 years (6 to 26), and one at 40 days after surgery because of repeated dislocations. The overall survival rate for aseptic failure of the acetabular component at ten years was 93.1% (95% confidence interval (CI) 86.5 to 96.7) when 53 hips were at risk, and at 23 years was 56.1% (95% CI 49.4 to 62.8), when 22 hips remained at risk. These long-term results are considered satisfactory for the reconstruction of an acetabulum presenting with inadequate bone stock and circumferential segmental defects. Cite this article: Bone Joint J 2013;95-B:887–92

A lesion similar to that described by Bankart in recurrent dislocation of the shoulder was seen in seven patients with recurrent dislocation of the peroneal tendons. Detachment of the periosteum had resulted in the formation of a false pouch on the surface of the lower end of the fibula; into this pouch the peroneal tendons could easily dislocate. Reattachment of the periosteum to drill holes in the fibula prevented dislocation, and this anatomical method of repair is described. This lesion is one of the causes of recurrent dislocation of the peroneal tendons

1. Two types of paralytic dislocation of the hips are discussed. 2. The mechanics of dislocation and the methods of reduction are described, with emphasis on the importance of maintaining or increasing stability where possible

We describe a case of rotational dislocation of the proximal interphalangeal joint of the ring finger. This injury was not initially appreciated and therefore closed reduction failed. The clinical findings included puckering of the skin on the dorsum of the joint and rotational incongruity on radiographs. At open reduction there was interposition of the lateral band. Identification of the pathology allows early successful treatment

1. The symptoms, signs and treatment of three patients with a posterior dislocation of the clavicle are described. 2. The value of tomography in confirming the diagnosis is outlined. 3. Certain experimental work has been done in an attempt to determine the factors necessary to produce this dislocation

Simultaneous bilateral posterior dislocation of the hip is very uncommon and most cases are caused by road accidents. Simultaneous bilateral posterior dislocation of the hip due to convulsions is extremely rare. We report the case of a man who was diagnosed late and operated on 15 weeks after the injury. We discuss the treatment of chronic dislocation of the hip and review the literature

1. Congenital dislocation of the hip in identical twins is reported. 2. The heredity of congenital dislocation of hip is discussed. Studies in twins show that congenital dislocation of hip is probably a hereditary dysplasia of the acetabulum and upper end of the femur, and that external factors play a less important role

We reviewed 16 patients with spina bifida and unilateral dislocation of the hip at an average age of 17 years. Nine had a high neurological level (thoracic to L3) and seven a low lesion (L4 to sacral). We assessed the influence of unilateral dislocation of the hip on leg-length discrepancy, hip pain, hip stiffness and pressure sores of the ischial tuberosity. In non-walking patients with high-level lesions, unilateral dislocation gave little functional disability and did not appear to require reduction. In walking patients with low-level lesions, leg-length discrepancy led to a poor gait and functional problems which could be prevented by reduction of the dislocation. In all patients with low lesions, surgery was successful in maintaining reduction; in two of five patients with high lesions it was unsuccessful

We used laser Doppler flowmetry (LDF) with a high energy (20 mW) laser to measure perfusion of the femoral head intraoperatively in 32 hips. The surgical procedure was joint debridement requiring dislocation or subluxation of the hip. The laser probe was placed within the anterosuperior quadrant of the femoral head. Blood flow was monitored in specific positions of the hip before and after dislocation or subluxation. With the femoral head reduced, external rotation, both in extension and flexion, caused a reduction of blood flow. During subluxation or dislocation, it was impaired when the posterosuperior femoral neck was allowed to rest on the posterior acetabular rim. A pulsatile signal returned when the hip was reduced, or was taken out of extreme positions when dislocated. After the final reduction, the signal amplitudes were first slightly lower (12%) compared with the initial value but tended to be restored to the initial levels within 30 minutes. Most of the changes in the signal can be explained by compromise of the extraosseous branches of the medial femoral circumflex artery and are reversible. Our study shows that LDF provides proof for the clinical observation that perfusion of the femoral head is maintained after dislocation if specific surgical precautions are followed

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

The incidence of congenital dislocation of the hip in 156 children with infantile idiopathic scoliosis was 6.4 per cent, approximately 10 times its frequency in the general population. In both of these deformities there was a predominance of girls (eight girls: two boys). In unilateral dislocation of the hip the convexity of the thoracic scoliosis was on the same side as the dislocation. Eight out of the 10 children with both deformities also had plagiocephaly

1. Recurrent dislocation of the elbow is caused primarily by collateral ligament laxity with secondary damage to the capitulum and head of radius. 2. The pathological changes resemble those of recurrent dislocation of the shoulder. 3. Subluxation or instability of the radial head is often associated with capsular ossification and deserves wider recognition because it may be confused with osteochondritis dissecans. 4. A simple method of soft-tissue repair has successfully prevented redislocation of eight elbows

Five knees with congenital dislocation were explored. The cruciate ligaments were found to be absent or hypoplastic. The results obtained by reconstructing an anterior cruciate ligament appear to be good. On the basis of dissections of foetal knees we believe that the cruciate ligaments are the main structures preventing an anterior dislocation of the knee in early foetal life; this deviation from the adult pattern is due to the bony configuration of the foetal knee. We therefore postulate that the basic defect in congenital dislocation of the knee is an absence or hypoplasia of the cruciate ligaments