The Influence of Hip OA Associated Gait Impairments on Efficiency of Gait and A Possible Rehabilitation

Gait impairment may contribute to reduced physical activity in hip osteoarthritis. Abnormal disease-related gait patterns could lead to higher energy expenditure during gait. The consequence of the greater energy used during walking due to gait impairment may contribute to reduce physical activity. However, the mechanism of how abnormal disease-related gait patterns lead to higher energy expenditure during gait and possible rehabilitation strategy in people with hip osteoarthritis is still unclear. To test the hypothesis that step length asymmetry is a modifiable factor associated with gait inefficiency, kinematic, and kinetic deviation in older adults with hip osteoarthritis, Gait analysis, oxygen consumption testing during walking, and split-belt treadmill training were conducted with women with unilateral hip osteoarthritis. Data were analyzed using Spearman correlation, linear regression models, and Repeated measures ANOVA. The results showed that the participants with hip osteoarthritis who demonstrated a greater step length asymmetry presented with lower sagittal plane hip range of motion during gait. Increased step length asymmetry was associated with lower mechanical energy exchange in people with hip osteoarthritis. In addition, more mechanical energy exchange was associated with lower O2 cost during gait. Moreover, Step length asymmetry and O2 rate significantly decreased, while mechanical energy exchange increased after split-belt treadmill training. Reduction of step length asymmetry was significantly associated with reduction of O2 rate. These results suggest that modifying step length asymmetry could enhance metabolic gait efficiency indirectly by improving mechanical energy exchange in women with hip osteoarthritis. This is important because metabolic gait inefficiency contributes to reducing daily physical activity to conserve energy.