[Pathogenesis and prevention of spastic hip dislocation].

Based on retrospective analysis of 82 hips of 41 patients with cerebral palsy, a pathogenetic model of spastic paralytic dislocation of the hip is introduced including recent observations of the normal hip development. According to this model the reduced activity of the gluteus maximus, medius, minimus and quadriceps femoris muscles, which normally cause a decrease of valgus and anteversion, results in an increased subluxating coxa valga antetorta with a consecutive dislocation. In order to prevent a dislocation, these muscle groups have to undergo increased activation. Since walking has to be to undergo increased activation. Since walking has to be considered the strongest stimulus for the dislocation-preventing hip abductors, hip extensors, outward rotators and knee extensors, the erect gait should be encouraged with statomotorically favored children early as possible. This can be supported by muscle relaxing surgery of the antagonistically effective hip flexors, hip adductors and inward rotators as well as the knee flexors. These muscle release operations will counteract, although to a limited extent, a dislocation even with a severely handicapped child who is unable to walk.