Return to sports, recreational activity and patient-reported outcomes after lateral unicompartmental knee arthroplasty

As the indication for unicompartmental knee arthroplasty (UKA) in recent years has been extended to young and more active patients, the expectations concerning the postoperative level of activity are high. The aim of the following study was to survey the activity level and the health-related quality of life of patients following lateral UKA. Forty-five patients were surveyed to determine their sporting and recreational activities at a mean follow-up of 3 years (range 2.0-4.3 years) after lateral UKA. We also assessed health-related quality of life of our patients at the time of the survey by use of the SF-36 Health Survey. Before the onset of the first restricting symptoms, 42 of 45 (93 %) patients were active in at least one sport compared to 43 of 45 (96 %) patients after surgery resulting in a return to activity rate of 98 %. Within 3 months, 56 % returned to their activities after surgery and 78 % within 6 months. The mean postoperative UCLA score was 6.7 (+/- 1.5). Two-thirds of the patients reached a high activity level (UCLA a parts per thousand yen7). Most common activities after surgery were biking, hiking and long walks. While high-impact activities showed a significant decrease, low-impact activities showed a significant increase. The main reason for a decrease in patients' level of activity was precaution. There are no statistically significant differences in the postoperative scores of our patients and those of a matched healthy reference population in the SF-36 scores. The results of the present study demonstrate that a vast majority (98 %) of our patients independent to age or gender returned to sports and recreational activity after lateral UKA. Two-thirds of the patients reached a high activity level. Activities patients were most participating in were low- or mid-impact, whereas high-impact activities were mostly given up. Further follow-up is necessary to assess the effect of activity on implant fixation and wear. Retrospective case series, Level IV.