Patient-Reported Outcomes Following Total Knee Arthroplasty With Multiple Sclerosis Demonstrate Similar Functional Outcome Measures: A Propensity-Matched Analysis.

Introduction: Multiple sclerosis (MS) may negatively influence the patient-reported outcomes measures (PROMs) when undergoing total knee arthroplasty (TKA). However, functional outcomes in this select population remains poorly characterized. This study aimed to compare clinical outcomes and rate of achieving Minimal Clinically Important Difference for Improvement (MCID-I) and Minimal Clinically Important Difference for Worsening (MCID-W) between MS and non-MS TKAs.

Methods: We did a retrospective analysis of 61 TKAs in MS patients performed between 2015 and 2022 and it was propensity matched in a 3:1 ratio with 123 non-MS patients. Preoperative and postoperative assessments included Patient-Reported Outcomes Measurement Information System Global Health Mental and Physical, Patient-Reported Outcomes Measurement Information System Physical Function short form 10-a (PF-10a), and Knee injury and Osteoarthritis Outcome Score-Physical Function Short-form scores. Patients were categorized based on achieving MCID-I, MCID-W, or showing "no change" after TKA.

Results: A total of 244 TKAs (61 MS and 183 matched non-MS) were analyzed. MS TKAs had similar length of stay but lower rate of home discharges (73.8% vs. 90.2%, P = 0.003) compared with non-MS patients. Notably, both cohorts had similar rates of achieving MCID-I and MCID-W among all four PROM scores. However, MS patients had a notable higher rate of 90-day postoperative complications (26.2% vs. 12.6%, P < 0.001), revision surgeries (11.5% vs. 4.4%, P = .045), and revisions (6.6% vs. 0.5%, P = 0.004).

Conclusion: Using MCID methodology, this study found that MS patients have similar rates of achieving MCID-I and MCID-W but have higher rate of postoperative complications, revision surgeries, and revisions when compared with non-MS patients. These findings highlight that despite the elevated risks of complications, MS patients can achieve similar improvements to their non-MS counterparts. Further investigations into the long-term outcomes of MS patients are warranted to the determine the effectiveness of this intervention.