Abstract
1. Six cases of necrosis of articular cartilage complicating slipping of the upper femoral epiphysis are reviewed: histological examination in one case showed death of the superficial two-thirds of the articular cartilage, with survival of a layer of basal chondrocytes. In all six cases, after severe initial reduction of joint space as seen radiographically, there was gradual return of joint space, suggesting some regeneration of articular cartilage. The prognosis after cartilage necrosis is therefore not always so bad as has been supposed.
2. Various hypotheses concerning the cause of cartilage necrosis complicating slipped epiphysis are reviewed. The precise cause remains unknown, but there is substantial evidence against its being a consequence of ischaemia of the femoral head.
