The Effect of Knee Flexion Contracture Following Total Knee Arthroplasty on the Energy Cost of Walking.

This study evaluated the energy cost of walking (C-w) with knee flexion contractures (FC) simulated with a knee brace, in total knee arthroplasty (TKA) recipients (n = 16) and normal controls (n = 15), and compared it to baseline (no brace). There was no significant difference in C-w between the groups at baseline but TKA recipients walked slower (P = 0.048) and with greater knee flexion in this condition (P = 0.003). Simulated FC significantly increased C-w in both groups (TKA P = 0.020, control P = 0.002) and this occurred when FC exceeded 20 degrees in the TKA group and 15 degrees in the controls. Reported perceived exertion was only significantly increased by FC in the control group (control P < 0.001, TKA P = 0.058). Simulated knee FCs less than 20 degrees do not increase C-w or perceived exertion in TKA recipients. (C) 2014 Elsevier Inc. All rights reserved.