Risk Factors for Early Periprosthetic Fracture after Primary Total Hip Arthroplasty

Abstract Periprosthetic fracture (PPF) after total hip arthroplasty (THA) is associated with adverse outcomes. Many studies have sought to determine risk factors for PPF, though controversy exists regarding several variables. This study sought to determine risk factors for early PPF using the National Surgical Quality Improvement Program (NSQIP) dataset. Patients with a primary current procedural terminology for THA were identified. The primary outcome was reoperation/readmission for PPF within 30 days. Multivariable logistic regression was utilized to adjust for confounding factors. A total of 159,234 patients were included in the study, of whom 195 patients (0.12%) had a PPF within 30 days, with a mean day of reoperation/readmission of 14.6 (standard deviation 7.7). A total of 68 patients (34.9% of those fractured) underwent one or more reoperations. In multivariable analysis, risk factors for PPF were higher body mass index (BMI; odds ratio [OR] 1.03 per mg/kg2, 95% confidence interval [CI] 1.0–1.05) and higher preoperative leukocyte count (OR 1.04 per 103/mL, 95% CI 1.01–1.06). Among females, age (OR 1.05 per year, 95% CI 1.04–1.07) was significantly associated with PPF, but a similar difference was not observed among males (OR 1.01, 95% CI 0.98–1.04). Controlling for patient age, there was no significant difference in risk of PPF for females versus males (p = 0.2213). PPF was associated with the development of additional complications (OR 4.10, 95% CI 2.68–6.27). This study identified risk factors for PPF after primary THA. These results have implications for preoperative planning and postoperative precautions among patients with particularly elevated risk of PPF.