To Bundle or Not to Bundle? The Financial Impact of Pathologic Hip Disease on Hip Arthroplasty Episodes of Care

Abstract Background The Comprehensive Care for Joint Replacement (CJR) model aims to support more efficient care for patients. We examined the impact of patient and surgical characteristics, post-acute care and clinical outcomes on episode of care (EOC) costs in patients undergoing hip arthroplasty for all diagnoses. Methods We retrospectively collected data from a large database of patients undergoing hip arthroplasty for oncologic and non-oncologic diagnoses between 2014 and 2017. We compared EOC costs and outcomes between the two groups using Student’s t-tests. We estimated the association between an oncologic-associated procedure and EOC costs from a multiple regression analysis. Results There were 2122 total patients included: 1993 in the non-oncologic group and 129 in the oncologic group. The length of stay was significantly greater in the oncologic group (7.2 days vs 4.2 days, p = 0.00). In the post-acute period, a greater proportion of oncologic patients was re-admitted (29% vs 14%, p = 0.05) and discharged to skilled nursing (93% vs 51%, p = 0.00). Index hospitalization costs (mean difference (MD) $1,561, p = 0.05), skilled nursing costs (MD $5,932, p = 0.001), and total EOC costs (MD $20,012, p = 0.00) were all greater in the oncologic group. Along with increasing age and fracture diagnosis, an oncologic diagnosis is independently associated with greater EOC costs from a multivariate analysis (β = 16,163 ± 2,258, p = 0.00, r2 = 29%) Conclusion CJR should incorporate risk adjustment for oncologic disease because hip arthroplasty for an oncologic diagnosis is associated with worse outcomes and greater costs than in the general population.