Dislocation Risk in Modern Total Hip Arthroplasty: Comparing Surgical Approaches With and Without Enabling Technology.

BACKGROUND

Dislocation remains a common complication following total hip arthroplasty (THA). Although surgical approach and enabling technologies may influence dislocation risk, their combined impact remains unclear. This study compared dislocation, periprosthetic fracture, and revision rates across four THA cohorts defined by surgical approach and technology use.

METHODS

We performed a retrospective cohort study of 3,243 consecutive primary THAs performed by seven fellowship-trained surgeons between May 2013 and December 2023. Patients were categorized into four cohorts: posterior approach (PA)-conventional (n = 1,817); direct anterior approach-conventional fluoroscopy (n = 979); direct anterior approach-navigation (n = 336); and PA-robotic (n = 111). The mean follow-up was 1.4 years (range, 90 days to three years). Multivariable logistic regressions were used to adjust for baseline differences.

RESULTS

Overall complication rates were low: dislocation 1.0% (33 of 3,243), periprosthetic fracture 2.2% (70 of 3,243), and revision 3.2% (104 of 3,243). Dislocation rates by cohort were PA-conventional 1.2%, direct anterior approach-conventional fluoroscopy 0.7%, direct anterior approach-navigation 0.3%, and PA-robotic 2.7% (P = 0.09). Neither unadjusted nor adjusted multivariable analyses demonstrated significant differences between cohorts for any outcome. Active tobacco use was significantly associated with increased dislocation risk (odds ratio 6.31, P < 0.001).

CONCLUSIONS

Multiple surgical approaches and technology platforms achieved excellent early outcomes with low complication rates in experienced hands. Although numeric trends favored direct anterior navigation (0.3% dislocation), differences were not statistically significant. Adequately powered prospective studies are needed to determine the incremental clinical benefit of enabling technologies.