The place of valgus extension femoral osteotomy in the late management of children with Perthes' disease.

Despite considerable research into the aetiology and management of Perthes' Disease, patients late with symptoms related to serious femoral head deformity. The process of progressive deformity is discussed and the clinical signs which recognize it identified. The clinical signs of the established condition are shortening, loss of abduction proceeding to a flexion/adduction contracture with unstable movement and hinge abduction on the dynamic arthrogram. Treatment must result in stable movement as the child stand and walks. This is achieved by a valgus/extension upper femoral osteotomy. The advantage of this procedure is that it relieves pain, improves leg length, restores the normal abductor lever and in consequence improves the limp, which is one of the patient's chief complaints. The results in the long term are discussed.