Acetabular component positioning after pelvic osteotomy: a retrospective comparison between the anterior and...

This study aimed to compare the acetabular component positioning accuracy and clinical outcomes between the direct anterior approach (DAA) and the posterolateral approach (PLA) for total hip arthroplasty (THA) in patients with a history of pelvic osteotomy.

This retrospective study included 37 hips from 35 patients who underwent THA following pelvic osteotomy between 2005 and 2023. The primary outcomes were acetabular component positioning accuracy within the target zones and Japanese Orthopaedic Association (JOA) scores. The component angles were measured using postoperative computed tomography.

The mean follow-up was 4.3 ± 3.0 years in the DAA group (short- to mid-term outcomes) and 11.2 ± 3.6 years in the PLA group (mid- to long-term outcomes). Significant improvement in JOA scores was observed in both groups, with no significant difference in final JOA scores. Mean inclination angles were similar with comparable variance. Although mean anteversion angles did not significantly differ, DAA demonstrated significantly lower variability. Optimal cup positioning within the target zones was significantly higher in the DAA group than in the PLA group. No dislocations occurred in the DAA group, whereas one did in the PLA group.

Both approaches demonstrated comparable clinical outcomes. Although the DAA showed higher rates of optimal cup placement and improved anteversion angle consistency, the overall clinical results were similar. The DAA and PLA are valid options for THA after pelvic osteotomy.