Predictors for activity following total and unicompartmental knee arthroplasty

Background Functional demands of patients undergoing knee arthroplasty are increasing. However, it remains unclear which patient-specific factors have an impact on postoperative activity and whether there is a difference between total and unicompartmental knee arthroplasties (TKA/UKA). Materials and methods This retrospective study analyzed 1907 knees with TKA ( n = 1746) or UKA ( n = 161), implanted for primary osteoarthritis. Pain and activity (lower extremity activity scale, LEAS) were assessed 2 years after surgery. High activity was defined as LEAS ≥ 14. Cohorts were compared using Kruskal–Wallis or Pearson-Chi-square test. A generalized least squares model was used to predict LEAS scores between cohorts adjusted for age, sex, BMI, Charlson Comorbidity Index, ASA score, and preoperative LEAS. Result There was no difference in pain 2 years after surgery between UKA and TKA ( p = 0.952). Preoperative LEAS was similar for UKA and TKA ( p = 0.994), and both groups showed significant (p