Improving the Accuracy of Acetabular Component Orientation: Avoiding Malpositioning

Many factors such as poor visualization, greater patient size, inaccuracies of mechanical guides, and changes in patient positioning during surgery can negatively impact acetabular component positioning1. Improper orientation contributes to an increased dislocation rate, limb-length discrepancy, component impingement, bearing surface wear, and revision surgery. Acetabular malpositioning also contributes to altered hip biomechanics, pelvic osteolysis, and acetabular component migration2-8. Despite the established definitions of acetabular safe zones, a recent analysis of United States Medicare total hip arthroplasty data revealed dislocation rates during the first six postoperative months to be 3.9% for primary arthroplasty and 14.4% for revision arthroplasty9. A recent report cited instability and dislocation as accounting for 22.5% of revision cases10.