Acetabular Component Positioning in Total Hip Arthroplasty: an Evidence-based Analysis

Advocates for navigated (NAV) total hip arthroplasty (THA) emphasize the potential for improved component placement. We reviewed published literature to investigate the claim of increased precision of acetabular component placement in navigated THA compared to conventional (N-NAV) THA. Major medical and publishers' databases were searched, making no restrictions for study type, yet restricting results to English-language sources. Nine studies of varying methodological quality involving 1479 THA with a mean age of 59.10 years were included. There was no statistically significant difference in mean acetabular component abduction and anteversion angles between the NAV and N-NAV groups. There was a statistically significant difference in the incidence of acetabular component placement in the "safe zone," with NAV having significantly more "safe placements" than N-NAV, regardless of the chosen safe zone. In addition, NAV had significantly fewer dislocations than N-NAV. These outcomes demonstrate the possible patient benefit from navigation and resulting tighter control of component position.