Sports activity and patient-related outcomes after fixed-bearing lateral unicompartmental knee arthroplasty

Background: Unicompartmental osteoarthrosis increasingly affects younger patients who have high expectations concerning their postoperative level of activity. However, there is no available data on the activity level after fixed-bearing lateral unicompartmental knee arthroplasty (UKA). The aim of this study was to report sports activity after fixed-bearing lateral UKA with a minimum two-year follow up. Methods: Nineteen patients were surveyed to determine their sporting activities at a mean follow up of 4.6 years (range 2.0-9.7 years) after fixed-bearing lateral UKA. We also assessed the Knee Injury and Osteoarthritis Outcome Score Joint Replacement (KOOS JR) Score and the University of California, Los Angeles activity scale (UCLA scale) at baseline and latest follow up. Results: Before the onset of the first symptoms, 15 of 19 patients were active in at least one sport compared with 13 of 19 patients after surgery. Eighty-six per cent of the patients returned to activity. Within 6 months, 68% returned to their activities after surgery. The mean postoperative UCLA score was 6.4 (+/- 1.3). Half of the patients reached a high activity level (UCLA >= 7). Most common activities after surgery were long walks, biking and hiking. High-impact activities showed a significant decrease. Conclusion: Eighty-six per cent of the patients were able to return to regular recreational and sporting activities. In general, a shift from high-impact to low-impact activities was observed. There was no difference in the number of disciplines performed. Overall, the session length and frequency remained unchanged. However, male patients and younger patients participated in sports less frequently compared with preoperative levels. (C) 2020 Elsevier B.V. All rights reserved.