Comparable PROM Gains and Satisfaction After TKA in Medicare Advantage vs. Traditional Medicare: A Multivariable Analysis of 6,010 Patients.

Abstract

As value-based care reshapes the landscape of orthopedic surgery, understanding how insurance type influences patient-reported outcomes (PROMs) after total knee arthroplasty (TKA) is increasingly important. While Traditional Medicare (TM) and Medicare Advantage (MA) differ significantly in structure and access, limited data exist comparing functional outcomes between these groups. This retrospective cohort study used a prospectively collected institutional registry to evaluate 6,010 Medicare beneficiaries who underwent primary TKA between 2016 and 2023. Patients were categorized by insurance type (TM or MA) at the time of surgery. Primary PROMs included the KOOS pain, physical function shortform (PS), and Joint Replacement (JR) subscales. Clinically meaningful improvement was assessed using minimal clinically important difference (MCID), substantial clinical benefit (SCB), and Patient Acceptable Symptom State (PASS) thresholds. Multivariable logistic regression was performed to evaluate the independent association between insurance type and each outcome, adjusting for demographic, clinical, and socioeconomic covariates. At baseline, MA patients had significantly lower KOOS pain, PS, and JR (p < 0.001). However, by 1-year follow-up, both groups achieved similar KOOS pain and PS scores, and comparable PROM improvements from baseline. MA patients had slightly lower KOOS JR scores (p = 0.006) at 1-year, but equivalent odds of achieving MCID, PASS, and SCB thresholds across all KOOS domains after multivariable adjustment. Patient satisfaction at 1 year also did not differ by Medicare plan type (p = 0.729). Despite presenting with worse baseline functional status, MA patients achieved similar postoperative outcomes, PROM gains, and satisfaction as their TM counterparts. These findings suggest that MA enrollment does not negatively impact patient-perceived benefit after TKA and may not warrant differential risk-adjustment in PROM-based value assessments.