Does Total Knee Arthroplasty Affect Physical Activity Levels? Data from the Osteoarthritis Initiative.

Total knee arthroplasty (TKA) is associated with improved patient-reported pain levels, function, and quality of life; however, it is poorly understood whether there is increased physical activity following TKA. Using data from the Osteoarthritis Initiative (OAI), we compare physical activity, as measured using an accelerometer, and patient-reported outcome measures of 60 patients who had already received a TKA with 63 patients who eventually received a TKA during the OAI study. There was no significant difference in activity levels between the two groups as measured by the accelerometer. Total WOMAC, KOOS Quality of Life, KOOS Knee Pain, and KOOS Function scores improved in the post-TKA compared to the pre-TKA group. In both pre-TKA and post-TKA groups, physical activity guidelines were met in only 5% or less.