No difference in sports participation and patient-reported functional outcomes between total knee arthroplasty and unicompartmental knee arthroplasty at minimum 2-year follow-up in a matched control study

Purpose The purpose of this study was to compare (1) sports participation and type of sports activity between TKA and UKA patients; (2) functional outcome and activity level between TKA and UKA; and (3) survivorship of the prosthesis in both the groups. Methods Prospectively collected data were obtained from an arthroplasty database to identify patients who underwent primary TKA and UKA. Both the cohorts of TKA and UKA were matched, controlling for age, sex, BMI and preoperative patient-reported outcomes, which include Oxford Knee Score (OKS), Tegner activity level, and visual analog scale (VAS) for pain score. After matching the two groups, 287 TKA and 69 UKA cases were available to be included in the study. Patients were evaluated pre- and postoperatively at 2 years for sports participation and sports preference, patient-reported outcomes, activity levels, and improvement in knee pain. Results The mean age of the TKA and UKA groups were 75.7 +/- 8.1 and 74.2 +/- 8.8, respectively. There was no significant difference between the two groups concerning the demographic variables. Significant improvement was noted in the weekly sports participation at the final follow-up compared to preoperative sports participation in both the TKA and UKA groups (p < 0.05). All patients were able to return to their desired sporting activity. No significant difference was noted between the two groups in sports participation preoperatively and postoperatively (p > 0.05). OKS, Tegner activity level and VAS for pain demonstrated a significant improvement from preoperative to 2 years postoperatively (p < 0.05). However, preoperative and postoperative patient-reported outcomes did not differ significantly between the TKA and UKA groups (p > 0.05). No case of revision surgery was found at a 2-year follow-up in both groups. Conclusion Traditionally, in isolated medial compartment osteoarthritis, UKA has been considered to be the procedure with better functional outcomes, but the current study demonstrates that when confounding factors are controlled, both TKA and UKA are effective, and offer similar functional outcomes and result in similar improvement in sports participation. These findings will be helpful to counsel the patients to choose the best suitable operative procedure between UKA and TKA.