2026 AAHKS Annual Meeting: In Vivo Impingement Risk During Activities of Daily Living Following Total Hip Arthroplasty

56 patients undergoing total hip arthroplasty (THA) through the direct anterior approach were evaluated, including 28 patients who received navigation-assisted THA and 28 matched controls who underwent conventional THA. The primary outcome was implant impingement risk, assessed using radiostereometric analysis (RSA) to measure minimum femoral neck-to-liner distances during functional activities. Secondary outcomes included the influence of implant geometry, component positioning, and spinopelvic mobility on impingement risk. Outcomes were assessed at least 6 months postoperatively across nine functional positions. Overall, the results revealed no significant difference in impingement risk between navigated and conventional THA. However, preoperative pelvic tilt and changes in sacral slope were important predictors of impingement risk, suggesting that spinopelvic mobility may be more influential than navigation in determining functional implant clearance.