[Is a dorsal access associated with an elevated luxation rate following total hip replacement?]

The use of the dorsal approach to the hip joint for insertion of an endoprosthesis is associated with a dislocation rate of 1-7%, which is higher than comparable operations using an anterolateral approach. In recent years an enhanced dorsal capsular reconstruction technique has been recommended with increasing frequency. This has reduced the likelihood of dislocation to 0-3%. Controlled studies comparing the dorsal approaches with and without soft tissue reconstruction have documented significantly better results after soft tissue reconstruction, with a probability of 0-3% for dislocation. In order to understand the dorsal instability of the hip joint following implantation of an endoprosthesis, we describe the pathophysiology and the possible reasons for dislocation. Many factors, such as cup position, length of the neck of the femoral implant, diameter of the implant head, the condition of the dorsal soft tissues and the patient's general condition, influence the outcome of the operation and the frequency of dislocation. Possible ways for preventing posterior dislocation are described with reference to both surgical technique and patient selection. The current range of surgical treatment options for recurrent dislocation are presented: modular cups, dual-head cups, constrained cups, high offset femoral neck and soft tissue interventions.