Risk Factors for Perioperative Nerve Injury Related to Total Hip Arthroplasty

Background: Nerve injury following total hip arthroplasty (THA) is a rare but serious adverse event. While prior studies have reported risk factors for nerve injury related to THA, they are limited to institutional data or small sample sizes. The current study aimed to leverage a large, national database to assess independent risk factors for sustaining nerve injury with THA. Methods: The 2010-2021 PearlDiver M157 database was queried for adult THA cases. Those with nerve injury within 90 days of THA were identified. Patient age, sex, body mass index (BMI), Elixhauser comorbidity index (ECI), fracture indication, and surgery type (index vs revision) were assessed for correlation with nerve injury by multivariate analyses. Results: Out of 750,695 THAs, 2659 (0.35%) had nerve injuries. Multivariate analysis revealed independent predictors of nerve injury in decreasing odds ratio (OR) order to include: revision procedure (OR: 2.13), female sex (OR 1.35), ECI (ECI 1-2 [OR 1.27], ECI 3-4 [OR 1.43], and ECI >= 5 [OR 1.59]) and age (OR 1.02 per decade decrease) (P < .05 for each). Pertinent negatives by multivariate analysis included underweight BMI (<20), and fracture indication. Individuals with morbidly obese BMI status (>= 35) had a decreased risk of nerve injury (OR 0.84, P = .019). Conclusions: THA-related nerve injury was found to be low at 0.35%. Factors independently associated with this adverse outcome were defined, of which the greatest risk was seen in revision procedures. These risk factors, derived from the largest cohort to date, may be helpful for risk stratification and patient counseling.