Effects of Acetabular Positioning in Total Hip Arthroplasty

Positioning of the acetabular component is critical to a successful total hip arthroplasty. This dissertation retrospectively examines 1,010 hips to study the effect of acetabular position on patient reported functional outcomes, which is not currently elucidated in literature. As the modified Hardinge approach is one of the most common surgical approaches used for total hip arthroplasty, we studied the same cohort to ascertain the accuracy of cup placement when using this approach. Moreover, the effect of acetabular position on polyethylene wear rates is prospectively examined in 43 hips with highly crosslinked polyethylene using radiostereometric analysis. Absolute and relative acetabular position was found to be weakly correlated with functional outcomes but the results are not clinically significant. Furthermore, cup position did not correlate with polyethylene wear in highly crosslinked polyethylene. The modified Hardinge approach was found to be 43.6% accurate in achieving the intended combined anteversion and inclination angle. While specific intraoperative targets for acetabular position may be important for hip stability, there may be no change in patient outcomes and polyethylene wear