Perthes' disease--a long term follow-up.

PERTHES' disease is a condition affecting children's hips in which the upper femoral epiphysis apparently becomes avascular and then revascularises over the next few years. We have undertaken a long term follow-up of patients with Perthes' disease to assess the outcome of the disease process over a long period of time with regard to the clinical condition of the hip. Most of the recent studies lay stress on the radiological assessment of the diseased hip reviewed over a relatively short period of time with little mention of the clinical condition of the hip with regard to pain, stiffness or function. Because major decisions regarding the form of treatment are made on information gained from these relatively short term follow-up reviews, we felt that it was important to assess the long term clinical result of the hip, treated conservatively, in order to try to understand the natural history of the disease process so that a valid judgement could be made on more recent methods of treatment. The age at onset of the disease process, the sex of the child, the Catterall ' grading and the amount of lateral extrusion of the femoral head from the acetabulum in the early stages of the disease were studied.