Accuracy of the acetabular index using the percutaneous assisted total hip technique.

In minimally invasive total hip arthroplasty (THA), proper acetabular component positioning can be difficult to achieve without navigational or intraoperative radiographic methods. Acetabular components placed in excessive abduction can lead to early failure and dislocation. This article describes a series of 74 consecutive primary THAs (71 patients, 3 bilateral) performed using a percutaneous assisted THA technique that does not require navigation, yet allows adequate visualization for accurate acetabular cup placement. No patients were excluded (because of body mass index or abnormal anatomy) from the study. Mean abduction angle for all hips was 45°. The goal was acetabular abduction angle between 35° and 55°. This goal was achieved in 72 of the 74 hips (97.3%). Proper acetabular abduction angle can be achieved in the majority of cases using this new soft-tissue sparing approach for THA.