Increased Complications and Cost Associated With Hip Arthroplasty for Femoral Neck Fracture: Evaluation of 576,119 Medicare Patients Treated With Hip Arthroplasty.

Background: The benefit of total hip arthroplasty (THA) for treatment of osteoarthritis (OA) and femoral neck fractures (FNFs) in the geriatric population is well established. We compare perioperative complications and cost of THA for treatment of OA to hemiarthroplasty (HA) and THA for treatment of FNF.

Methods: Data from the Centers for Medicare & Medicaid Services were used to identify all patients 65 years and older undergoing primary hip arthroplasty between 2013 and 2017. Patients were divided into 3 cohorts: THA for OA (n = 326,313), HA for FNF (n = 223,811), and THA for FNF (n = 25,995). Generalized regressions were used to compare group mortality, 90-day readmission, thromboembolic events, and 90-day episode costs, controlling for age, gender, race, and comorbidities.

Results: Compared to patients treated for OA, FNF patients were older and had significantly more comorbidities (all P < .001). Even among the youngest age group (65-69 years) without comorbidities, FNF was associated with a greater risk of mortality at 90 days (THA-FNF odds ratio [OR] 9.3, HA-FNF OR 27.0, P < .001), 1 year (THA-FNF OR 7.8, HA-FNF OR 19.0, P < .001) and 5 years (THA-FNF hazard ratio 4.5, HA-FNF hazard ratio 10.0, P < .001). The average 90-day direct cost was $12,479 and $14,036 greater among THA and HA for FNF respectively compared to THA for OA (all P < .001).

Conclusion: Among Centers for Medicare & Medicaid Services hip arthroplasty patients, those with an FNF had significantly higher rates of mortality, thromboembolic events, readmission, and greater direct cost. Reimbursement models for arthroplasty should account for the distinctly different perioperative complication and resource utilization for FNF patients.