Transient ischaemia of the proximal femoral epiphysis in the child. Interpretation of bone scintimetry for diagnosis in hip pain.

99mTc-MDP-scintimetry was performed in 25 consecutive cases of radiographically silent transient synovitis of the hip in children. Fourteen cases had normal scintimetry; seven cases had an increased uptake in the epiphysis; four cases had markedly defective uptake in the epiphysis, indicating interrupted vascular supply. At repeat scintimetry 6 weeks later, the uptake was normal or increased in three of these four cases; the one case with a persistent defect was the only case in this series who later developed radiographic evidence of Legg-Calvé-Perthes' disease. In some cases presenting with clinical symptoms of synovitis of the hip, there is a transient, spontaneously recovering ischaemia of the proximal femoral epiphysis, not followed by radiographic evidence of necrosis. This should be considered in attempts to make a pre-radiographic diagnosis of Legg-Calvé-Perthes' disease by radionuclide methods.