Performance-based functional assessments are rarely performed, but the results from these tests reveal that recovery of function to preoperative levels takes longer, as compared to questionnaire scores, and functional performance of TKA cohorts never approach age-matched population norms.
The extent of deficits can be dramatic. For example, at 12 months after surgery, patients with TKA perform stair climbing at approximately half the speed of healthy
age-matched groups.
Physically demanding tasks, such as stair climbing, squatting, gardening, and heavy domestic duties, are typically associated with greater functional limitations and less improvement after surgery relative to walking tasks, which are typically less demanding.
The residual disability following TKA has a large potential for societal impact, as hundreds of thousands of people undergo TKA each year.