Introduction: rapidly destructive hip arthropathy is a recognised condition. Some authors considered it as a subset of osteoarthritis but none has identiþed the aetiology, pathogenesis or risk factors. Patients and methods: Authors present 14 cases of an extreme subset of rapidly destructive hip arthropathy. The radiological deterioration occurred dramatically over a short period ranging from 2 weeks up to few months. Loss of femoral head ranged from 25% up to 100% of the head volume. Acetabulum was damaged in all cases and femoral neck was partially lost in 9 cases (up to 75%). 4 cases were associated with dislocation. Age ranges from 53 to 85, female to male ratio (8 to 6), 2 patients had bilateral disease. Results: Clinical and radiological features were similar to those of neuropathic joint, infection, neoplasia, or avascular necrosis. However these conditions were excluded by further investigations; laboratory, imaging, surgical exploration and histopathology. All patients underwent hip arthroplasty. Some common (at risk) features included elderly patients, long history of receiving strong NSAIDs, radiologically atrophic and predominantly lateral disease. Conclusion: It appears that this condition represents a new entity but authors were not able to identify the aetiology. Awareness of this condition is important and at risk patients should be closely monitored.

We reviewed 15 children with transient synovitis of the hip who had aspiration of an effusion under local anaesthesia with ultrasound guidance. There were no significant complications; aspiration was useful for diagnosis and gave considerable symptomatic relief. We discuss the role of ultrasound in diagnosis and treatment.

One-hundred newborn children at high risk of hip instability were prospectively assessed clinically and by ultrasound. The decision to treat was based only on the clinical examination. At the age of three months all the children were evaluated clinically and with an anteroposterior radiograph of the pelvis. None of the standard ultrasound measurements of acetabular depth and femoral head cover correlated with the outcome at three months. Dynamic assessment of stability was the only ultrasound technique that had a significant relation with outcome.