Health Status of Total Hip Versus Total Knee Arthroplasty Patients and Possible Effects on Decisions Regarding Surgical Location, Cost, and Access to Care

Background: Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are no longer considered inpatient-only procedures. Qualifying for inpatient status reimbursement requires additional, unreimbursed administrative effort, and may limit care to these patients. Purpose: We sought to evaluate and compare the overall health status of patients receiving THA and TKA. Methods: We conducted a retrospective review evaluating 2207 patients undergoing primary THA and TKA from 2015 to 2018 at a single institution. Clinical parameters, surgical procedure, medical history, laboratory values, length of stay (LOS), and discharge location were recorded and compared between the 2 groups. Results: In 2202 patients, we observed differences for body mass index (THA = 29.4 ± 0.4, TKA = 32.1 ± 0.3), low-density lipoprotein cholesterol levels (THA = 105.8 ± 13.5 mg/dL; TKA = 128.6 ± 13.7 mg/dL), and blood glucose levels (THA = 98.2 ± 1.7 mg/dL; TKA = 101.4 ± 1.3 mg/dL), indicating that TKA patients were more likely than THA patients to be classified as obese, hypercholesterolemic, and hyperglycemic. We observed longer LOS in THA patients (51.25 hours, 95% CI ± 3.87 hours) than in TKA patients (36.93 hours, 95% CI ± 1.17 hours). A greater proportion of TKA patients were discharged home (81.97%, N = 1155) rather than to additional care facilities compared with THA patients (71.84%, N = 539). Conclusion: In this retrospective study, we observed that TKA patients had higher rates of comorbidities than did THA patients, but TKA patients spent less time in the hospital and were more likely to be discharged home. Future studies should evaluate reasons for poor clinical outcomes for patients undergoing total joint arthroplasty with an outpatient designation.