How Do the Outcomes of Total Hip Arthroplasty for Oncologic Hip Reconstruction Compare With Those Performed for End-Stage Osteoarthritis?-A Propensity-Matched Cohort Study.

Background: Compared with total hip arthroplasty (THA) for end-stage osteoarthritis, poorer outcomes have been reported in THA for oncologic hip reconstruction because of resection of surrounding stabilizing structures and higher patient comorbidity profile. In a matched cohort, we sought to compare postoperative outcomes between these cohorts.

Methods: A retrospective study of patients who underwent THA for oncologic (primary tumor or metastatic bone disease) or nononcologic (end-stage osteoarthritis) indications was conducted. The oncologic group was further subdivided into simple and complex; the latter included patients with concurrent proximal femur arthroplasty, Harrington reconstruction, and/or hemipelvectomy. Propensity-score matching based on age, sex, body mass index, and age-adjusted Charlson Comorbidity index was done. Primary outcomes were the cumulative incidence of reoperation, revision, and dislocation.

Results: After propensity-score matching, 150 nononcologic and 50 oncologic THA were included. At 2 years, the oncologic THA group increased rates of reoperation (25.4% vs. 1.8%), revision (25.4% vs. 1.3%), and dislocation (10.2% vs. 0.6%) compared with the nononcologic group. At 5 years, the oncologic THA group similarly showed poorer implant survival for all metrics; differences between the groups were notable at both time points ( P < 0.001). We observed no differences in reoperation, revision, and dislocation rates between the simple and complex oncologic THA subgroups ( P > 0.05). The oncologic THA group showed a higher rate of 90-day overall complications and readmission, as well as higher rates of 2-year (15.7% vs. 4.8%; P = 0.01) and 5-year (35% vs. 14.1%; P = 0.001) mortality as compared with the nononcologic group.

Conclusion: Although oncologic THA displayed poorer outcomes than their nononcologic counterparts, oncologic THA complexity did not play a role in surgical outcomes. These findings allow for improved patient expectations regarding the differing complication profile for different orthopaedic subpopulations. Further studies are needed to determine adequate surgical techniques to mitigate the increased complication profile of oncologic patients.