Author(s): REN, X., LUTTER, C., KEBBACH, M., BRUHN, S., YANG, Q., BADER, R., TISCHER, T., Institution: ZHEJIANG NORMAL UNIVERSITY, Country: CHINA, Abstract-ID: 1294

INTRODUCTION:
The lower limb maintains stability after a gait perturbation by establishing a new base of support and generating joint moments, thus contributing to balance recovery. However, different perturbations may require distinct strategies, especially for patients. This study was to investigate the characteristics of normal gait and the first recovery step following forward trip perturbations (trip_Rec1) and compensatory strategies produced by the lower extremities in patients with knee osteoarthritis (OA).
METHODS:
Nine patients with knee OA and 15 age-matched able-bodied healthy older individuals volunteered to participate in this investigation. The measurement sessions were performed on the Gait Real-time Analysis Interactive Lab including normal walking and forward tripping perturbed walking. Lower limb joint angles and joint moments were recorded. An independent samples t-test and one-dimensional statistical mapping were employed for statistical analyses of knee flexion excursions and ankle, knee, hip moments throughout the gait cycle between patients with knee OA and older adults, respectively.
RESULTS:
Patients with knee OA demonstrated significantly smaller knee flexion excursion than older adults during normal gait (10.70±5.51 vs 17.92±3.48, P=0.0007), whereas no significant difference was observed in the trip_Rec1. At the hip joint, significant differences in sagittal moment were observed between the two groups, at 41.04-58.24% (P < 0.001) in the stance phase and at 71.17-84.74% (P < 0.001) in the swing phase in normal gait, as well as at 56.44-62.63% (P = 0.003) in the stance phase in trip_Rec1. Significant differences in frontal moment were solely observed between the two groups in normal gait at 32.45-41.3% (P < 0.001).
CONCLUSION:
Patients with knee OA have an increased potential risk of falls during walking due to inherent pathological characteristics. Moreover, the compensation for the hip abduction moment in the frontal plane may keep the gait pattern of patients with knee OA largely consistent with a normal gait as well as with older adults in terms of the stance phase (%). These findings have clinical implications for the rehabilitation of fall-prone older adults and patients requiring gait stabilization, leading to the relevance of physical therapies such as balance-based gait perturbation training.