Failures of open reduction in developmental dislocation of the hip.

Eight patients with the same number of developmental dislocated hips were initially treated with open reduction through an anterolateral approach. The hips then became dislocated again. There were six girls, with a mean age at first open reduction of 13.3 months. We treated the hips with a new open reduction through an anteromedial approach. A constricted anteromedial capsule was always found as the main factor; all had an intact anteromedial capsule, there was an inverted transverse ligament in three cases and a very tight psoas tendon in another three cases. All were reduced, without complications and with only one simultaneous bone procedure. Risk of avascular necrosis and residual dysplasia could not be evaluated with this follow-up. We conclude that in any open reduction for developmental dislocation of the hip the surgeon must consider a release of the anteromedial capsule, which we have found to be the most important factor in technical failures.