Plain radiographs: Idiopathic chondrolysis of the hip

The hallmark of idiopathic chondrolysis of the hip is narrowing of the hip joint space without frank osteophyte formation in conjunction with periarticular osteopenia in a young female. The plain radiographs A and B above depict bilateral idiopathic chondrolysis of the hip. Note the concentric and uniform narrowing of the joint space bilaterally. Also observe the bilateral protrusio acetabuli (arrows) and periarticular osteopenia. Both of these hips were active on nuclear bone scan.