Sport and Physical Activity Following Primary Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

Background: This systematic review and meta-analysis aims to analyze the sport habits of patients before and after primary total knee arthroplasty (TKA) by answering the following questions: (1) Is there a postoperative improvement of sport activity based on validated activity scores? (2) Does age influence the postoperative improvement of sport activity based on validated activity scores? (3) What are the preoperative and postoperative sport participation rates and the return to sport rates (RTS)? (4) What are the sport disciplines and sport patterns? Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, MEDLINE and Scopus were searched for studies reporting the physical activity level and sport habits of patients before and after primary TKA based on validated activity scores or an activity questionnaire. Random effect models were implemented to pool the mean differences (MDs) of activity score values and the difference between preoperative and postoperative sport participation rates. Results: Twenty-five studies were included reporting on 6035 TKAs. Physical activity levels improved significantly according to the University of California, Los Angeles (UCLA) activity score (MD 1.55, 95% confidence interval [CI] 0.35-2.76, n = 1239, I-2 = 99%, P < .01) and the Tegner score (MD 1.14, 95% CI -0.48 to 2.76, n = 483, I-2 = 93%, P < .01). Younger patients (<= 55 years) had the highest improvement in the UCLA activity scores following primary TKA (MD 3.12, 95% CI -1.79 to 8.04, n = 67, I-2 = 96%, P < .01). Sport participation decreased slightly but not significantly (incidence rate difference -8%, 95% CI -0.14 to -0.2, n = 2673 patients, I-2 = 38%, P = .09). The median RTS was 71.2%. Patients predominantly engaged in low-impact sports, especially walking, cycling, and swimming. Conclusion: According to validated activity scores, the level of physical activity significantly increases following primary TKA. Young patients (<= 55 years) had the highest gain in physical activity according to the UCLA activity score following primary TKA. Sport participation shows a slight but nonsignificant decrease; intermediate and high-impact sports were abandoned to a large degree while participation rates for low-impact sports predominantly increased. RTS varied, although approximately 70% resume sport activities. (C) 2020 Elsevier Inc. All rights reserved.