Predictors of immobility following surgery for periprosthetic hip fractures

Periprosthetic femoral fractures (PPF) following total hip arthroplasty (THA) are a growing clinical challenge, particularly in the elderly. Postoperative mobility is a key determinant of outcome, yet little is known about how surgical treatment and weight-bearing protocols influence functional recovery in this population. We conducted a retrospective cohort study of 186 patients aged ≥ 65 years treated surgically for Vancouver type B or C PPF between January 2017 and August 2023 at a level 1 trauma center. Patients underwent either open reduction and internal fixation (ORIF) or revision arthroplasty. Postoperative weight-bearing protocols were categorized as full weight bearing (FWB) or partial weight bearing (PWB). The primary outcome was mobility status at hospital discharge. Binary logistic regression was used to identify independent risk factors for immobility. Of the 186 patients included (mean age 82.4 ± 7.4 years), 64.5% were mobilized with FWB. In the ORIF group, patients allowed FWB were significantly older (85.5 ± 7.4 vs. 80.2 ± 6.3 years, p < 0.001). No significant differences in mobility, complication rates, revision surgery, or in-hospital mortality were observed between weight-bearing regimens, regardless of the type of surgery. Logistic regression identified intraoperative blood transfusion (OR = 3.17) and higher ASA scores (ASA III: OR = 9.10; ASA IV: OR = 32.03) as independent predictors of postoperative immobility. Neither the postoperative weight-bearing protocol nor the surgical procedure had a significant impact on mobility outcomes. This study examines postoperative weight-bearing strategies on clinical outcomes in patients with periprosthetic hip fractures and simultaneously identifies independent risk factors associated with postoperative immobility. Our findings suggest that mobility outcomes are more influenced by patient-related factors than by surgical procedure. Our findings support the safe implementation of full weight-bearing protocols in elderly patients following periprosthetic femoral fractures, regardless of the type of surgical intervention.