Factors Associated With Dynamic Balance in People With Knee Osteoarthritis

Objective: To identify potential neuromuscular factors associated with dynamic balance in individuals with knee osteoarthritis (OA). Design: Cross-sectional observational study; backward stepwise multiple linear regression was used to identify factors associated with dynamic balance in 2 statistical models. Setting: University clinical research laboratory. Participants: Individuals aged >= 50 years (N=52) with osteoarthritic changes on radiograph participated. Interventions: Not applicable. Main Outcome Measures: Dynamic balance was assessed using the Community Balance and Mobility Scale (CB&M). Potentially modifiable neuromuscular factors associated with dynamic balance were measured, including the sum of concentric and eccentric lower-extremity muscle strength, 2 quadriceps-hamstrings muscle strength ratios, knee joint proprioception (joint position sense), anticipatory postural control velocity, and knee joint range of motion. Results: The first model for explaining variance in CB&M scores consisted of eccentric lower-extremity muscle strength and knee joint range of motion as factors. The model containing these 2 variables explained 50% of the variance in CB&M scores. The second model adjusted for descriptive variables, including age, body mass index, and knee pain, contained only the neuromuscular variables eccentric lower-extremity muscle strength, and explained 68% of the variance in CB&M scores. Conclusions: These results suggest that muscle strength and, to a lesser extent, knee joint range of motion are important factors associated with dynamic balance as measured by the CB&M and should be considered in dynamic balance interventions. (C) 2015 by the American Congress of Rehabilitation Medicine