Analysis of postural adaptation in elderly individuals with unilateral knee osteoarthritis: implications for postural control and gait initiation

Abstract

Objective: To investigate the impact of unilateral knee osteoarthritis on static and dynamic postural control during gait initiation in elderly individuals, comparing them to active, healthy older adults. Methodology: Forty elderly individuals were divided into two groups: G1, composed of 20 individuals with unilateral knee osteoarthritis awaiting total knee arthroplasty (TKA), and G2, composed of 20 active elderly individuals without osteoarthritis. Biomechanical assessments were conducted using a plantar pressure platform to measure variables related to the Center of Pressure (COP) during bipedal postural control with eyes open and closed, and gait initiation. The variables analyzed included COP displacement amplitude in the anteroposterior (COPAP) and mediolateral (COPML) directions, and mean COP displacement velocity in the anteroposterior (VELAP) and mediolateral (VELML) directions. Results: Individuals with knee osteoarthritis (G1) exhibited greater COP displacement amplitude in the anteroposterior direction (COPAP) during bipedal postural control with both eyes open and closed compared to the control group (G2). During gait initiation, G1 displayed greater COPAP and COPML values in the anticipatory phase compared to G2. No significant differences were observed between groups in the execution phases of the first and second steps. Conclusion: Unilateral knee osteoarthritis negatively affects postural control, especially static and dynamic balance, in elderly individuals. The results suggest the need for targeted intervention programs to improve postural control and dynamic stability in older adults with knee osteoarthritis, aiming to reduce fall risk and enhance mobility.