The potential utility of patient-reported range of motion after total knee arthroplasty

Total knee arthroplasty (TKA) is a safe, cost-effective treatment for pain relief and improvement of knee function in patients with knee arthritis. The procedure has become extremely common in the United States: in 2008 alone, over 615,000 TKAs were performed mainly driven by the high prevalence of symptomatic osteoarthritis (OA). Candidates for the procedure typically have diminished quality of life due to persistent knee pain and significant functional limitation. OA is the main clinical indication for TKA (approximately 97% of cases). Advanced OA is associated with reduced knee range of motion (ROM), which leads to increased disability: an individual requires 67° of knee flexion to walk normally, 83° of flexion to climb stairs, 90° to walk down stairs, 105° to get up from a chair, and 115° to rise from a sofa.