Legg-Calvé-Perthes Disease—Pathogenesis and Evolution

We suspect that the primary lesion in Legg-Calvé-Perthes disease is a weakening and disruption of the upper femoral epiphyseal plate. Aseptic necrosis of the femoral head results from the interruption of the retinacular vessels when they cross the cartilage at the edge of the disrupted plate. Early clinical signs of Legg-Calvé-Perthes disease are related to synovitis, which usually follows total femoral-head necrosis and collapse of the center of ossification. The speed of recovery of the necrotic epiphysis is related to the severity of the epiphyseal-plate lesion and of bone collapse. No evidence of thyroid dysfunction was discovered in our patients. Administration of large doses of l-triiodothyronine during periods of from six to eighteen months did not alter the speed of reconstruction of the necrotic femoral head.