SIMULTANEOUS VERSUS STAGED TOTAL HIP ARTHROPLASTY FOLLOWING ACETABULAR FRACTURE FIXATION: A COMPARISON OF OUTCOMES

Acetabular fractures present a challenge. Anatomical reduction can be achieved by open reduction and internal fixation (ORIF). However, in elderly patients with complex fracture patterns and osteoporotic bone stock, “fix and replace” has become an option in the management of these injuries. This involves ORIF of the acetabulum to enable insertion of a press fit cup and subsequent cemented femoral stem at the index surgery. A Retrospective analysis of all operatively managed acetabular fractures by a regional Pelvic and Acetabular Trauma service (01/01/2018-30/05/2023) STATA used for analysis. 34 patients undergoing “fix and replace” surgery. Of the 133 patients managed with ORIF, 21 subsequently required Total Hip Arthroplasty (THA). Mean follow up was 2.7 years versus 5.1. There was no statistical significance between the two groups with regards to BMI or sex. Mean age in the “fix and replace” group was 68 compared to 48 in the ORIF and subsequent THA group. This reached statistical significance between the two groups (p=0.001).ASA and Charlson Comorbidity Index (3 and 3 in “fix and replace” and 2 and 1.2 in ORIF to THA group) and Charlson Comorbidity Index both were statistically significantly different (p=0.006 and p=0.027, respectively). High energy mechanism of injury accounted for 56% of the “fix and replace” group compared to 48% in the ORIF to THA. 74% of “fix and replace” were associated fractures compared to 53% of ORIF to THA. Wait to surgery was 3 days for “fix and replace” while 186 days was the mean wait time from listing to THA for the ORIF to THA group. Complication rate was 41% versus 43% in the two groups. 14% in the ORIF to THA group developed PJI versus 6% in “fix and replace”. Fix and replace allows early mobilisation in frailer, elderly patients. Our results show fewer returns to theatre and less PJI in patients having arthroplasty as part of “fix and replace” than subsequent to Open reduction internal fixation.