Is there a functional benefit to obtaining high flexion after total knee arthroplasty?

Abstract

Clinical evidence is lacking to support the functional benefit of high flexion after total knee arthroplasty (TKA). A retrospective review of 511 TKAs in 370 patients was performed. The mean follow-up was 3.7 years (range, 2-8 years). Regression analysis determined the effect of obtaining high flexion (>125 degrees ) on Knee Society, stair, function, and pain scores. Of 511 TKAs, 340 (66.5%) obtained range of motion greater than 115 degrees , and 63 (12.3%) TKAs obtained high flexion greater than 125 degrees . There was no difference between the patients who obtained flexion greater than 115 degrees and those who obtained high flexion greater than 125 degrees in Knee Society scores (P = .34) and function scores (P = .57). Patients with greater than 125 degrees of flexion are 1.56 times more likely to demonstrate optimal stair function (P = .02). Obtaining flexion greater than 125 degrees after TKA does not offer a benefit in overall knee function. However, obtaining a high degree of flexion appears to optimize stair climbing.