Lower limb biomechanics in individuals with knee osteoarthritis before and after total knee arthroplasty surgery.
Total knee arthroplasty (TKA) patients experience significant reductions in pain following surgery, yet many patients do not achieve normal joint function due to retaining pre-surgery knee joint loading pattern.
The aim was to identify biomechanical changes in the lower limb in the sagittal plane following TKA prior to and 12 months following surgery in 32 end-stage osteoarthritis patients (mean 68yrs) who needed to be able to walk at least 45m independently. 28 asymptomatic age-matched participants served as controls. Gait analysis was performed using 3D motion analysis system (VICON, 10 cameras,100 Hz). Physical function, pain and stiffness were assessed using WOMAC index.
TKA patients walked significantly slower, with shorter stride length and reduced cadence before surgery compared to the control group. These parameters remained lower 12 months post-surgery compared to the control group. Improvements were found for pain, stiffness, function and the overall WOMAC score. Within-group differences revealed no changes between pre- and post-surgery for hip measures. Peak knee flexion moment increased following surgery. Compared to controls, TKA-patients demonstrated greater ankle dorsiflexion before and after surgery.
Despite improvements in pain and self-reported function, biomechanical changes in the knee and ankle were identified before and following TKA because of retention of pre-surgery gait patterns with the ankle compensating for impaired knee function. Rehab strategies should not only focus on improving knee function, but also on gait retraining. > From: Levinger et al., J Arthroplasty 28 (2013) 994-999. All rights reserved to Elsevier Inc.
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