Abstract
Valid criteria of gait evaluation have been required in clinical practice. The method for evaluation must be objective and simple although human gait is inherently complex and many parameters are tangled with each other. In order to find a solution to this problem, a new evaluation method has been developed. The gait records of 211 cases of patients with hip diseases have been measured. The measurements of five gait parameters, namely, angular displacement for joint of lower extremities, floor reaction forces, trajectory for point of force application, gait duration time, and step length, are performed using a minicomputer. Gait data are normalized, numerized and summarized in synthetic values by principal component analysis. As a result, two principal components which reveal 'general walking ability' and 'balance between the symmetry and the activity' are obtained. A patient's factor score for these principal components are in good agreement with his or her clinical situation. Gait characteristics caused by the extent of the lesion and the method of treatment procedure could be compared on a scale using factor scores. Gait data are averaged among the patients of similar factor scores and compared with each other. Some characteristics of the gait of patients for each treatment procedure, such as conservative treatment, total hip replacement, and hip fusion, are clarified. Further, the joint moments of stance phase due to the floor reaction force are calculated for some patients. The results give the following information: 1) For the conservative treatment, Walking patterns are affected by the pain, the leg-length discrepancy and the range of the motion of joints. 2) Patients with total hip replacement walk at a slow speed but with good symmetry while the patients with hip fusion walk at a high speed but with prominent unbalance. 3) The moment of the hip joint is large for patients with serious lesions but is reduced by operation.
