Perioperative Femur Fractures in muscle sparing anterolateral - Modified Watson-Jones approach to primary total hip arthroplasty: A retrospective cohort study

Background: Periprosthetic femur fractures (PFF) are a rare early complication in primary total hip arthroplasty (THA) that may result in revision and burden the healthcare system. A previous study identified a PFF rate of 8.3 % at 90 days with the modified anterolateral Watson-Jones (AL) approach to THA. This study assesses the PFF rate and risk factors with this approach at 90 days and 1-year post-operative follow-up. Methods: 580 primary THAs performed using the AL approach were retrospectively reviewed for risk factors associated with perioperative PFF including demographics, intra-operative and postoperative factors, and disposition. Results: 507 included patients had a 90-day PFF rate of 1.6 % (n = 8): 6 intraoperative (1.2 %), and 2 postoperative (0.4 %), significantly lower than previously reported (p < 0.001). 1 additional postoperative PFF fracture was operatively managed with open reduction internal fixation (ORIF) on day 302; 1-year PFF rate was 2.5 %. All fractures healed uneventfully after treatment. The 1-year return to operating room rate for PFF was 0.3 %. Patients with PFF were significantly older (p = 0.036) compared to non-PFF patients. Implant type significantly predicted PFF. Conclusion: The rarity of PFF among our cohort highlights the efficacy of the AL approach to avoid this complication.