Quantitative gait analysis of patients with bilateral hip osteoarthritis excluding the influence of walking speed

Background. The purpose of this study was to investigate gait characteristics of patients with bilateral hip osteoarthritis (BHO) independent of walking speed. Methods. We measured gait parameters in 12 BHO patients during free walking activities and in 12 normal adults during both free walking and slow walking activities using a three-dimensional computerized gait analysis system. Results. Patients with BHO had a lower walking speed, step length, and cadence than normal subjects during free walking. When compared with normal subjects walking at a slow speed, the walking speed difference among BHO patients disappeared, although BHO patients retained a relatively high cadence. Kinematic and kinetic factor analysis of BHO patients at free speed compared to normal subjects walking at a slow speed showed a forward-tilted pelvic angle in the BHO patients that dropped to that of the ipsilateral side during the stance phase. The peak extension and abduction angle of the hip and the peak abduction moment of the hip were all low, whereas the peak generation power of the ankle was high in BHO patients. Conclusions. Gait characteristics of patients with BHO, independent of walking speed, were as follows: (1) increased cadence and ankle generation power; (2) reduced step width, hip extension, and abduction angle as well as a lower hip abduction moment; (3) maintained forward tilting of the pelvis during gait cycle; and (4) appearance of a dropped pelvis during the stance phase.