Dislocation of the hip in cerebral palsy. Natural history and predictability.

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 place of threaded pin fixation in the treatment of slipped upper femoral epiphysis.

Pin fixation in the treatment of slipped upper femoral epiphysis was evaluated in 60 patients admitted to the authors' hospital in Melbourne between 1970 and 1978. Forty-three cases were reviewed at an average of eight years following initial treatment. For chronic slips, in situ fixation with pins prevented further slip and promoted growth plate closure. The complication rate was low. Best results were achieved with two or three threaded pins placed into the posteroinferior segment of the femoral head to avoid avascular necrosis. Early upper femoral osteotomy was not required, as considerable bone remodeling occurred even after growth plate closure. In contrast, avascular necrosis was common following treatment of acute, severe slips, even with gentle internal rotation of the leg to reduce the acute component of the slip and pinning.

The lumbar theco-peritoneal shunt syndrome and its surgical management.

Seven patients treated in infancy by a lumbar theco-peritoneal shunt for idiopathic communicating hydrocephalus presented later in childhood after developing a characteristic orthopaedic syndrome. This included a severe, rigid and progressive lumbar hyperlordosis, severe bilateral restriction of straight leg raising and abnormalities of stance and gait. Four of the patients, who had severe hyperlordotic curves of over 90 degrees, required operations to correct their extreme deformity. The recommended method of correction is a three-stage procedure: first, anterior wedge resection osteotomies at several levels in the lumbar spine, then a period of "90-90" femoral traction, and finally a posterior fusion and stabilisation using Harrington instrumentation. The results were good, with few complications.

Simultaneous dislocation of the elbow and the proximal radio-ulnar joint.

Simultaneous dislocation of the elbow and the proximal radio-ulnar joint is rare. Two children with this uncommon injury are reported. One child had a transverse divergent dislocation that was treated successfully by closed reduction. The other had a convergent dislocation (or translocation of the radius and ulna) which needed open reduction. Convergent dislocation is even rarer than transverse divergent dislocation, and this is believed to be the first time it has been reported.

Synovial chondromatosis of the knee in childhood. A report of two cases.

Synovial chondromatosis is a rare metaplastic condition affecting major synovial joints. It is extremely rare in childhood. The two children reported here are believed to be the youngest patients with this condition affecting the knee to have been described in the literature.