A Musculoskeletal Modeling Study of Lower-Limb Kinematics and Muscle Activities during Level Walking in Patients with Knee Osteoarthritis

Abstract

Background: Knee osteoarthritis (OA) is a common disease potentially limiting the locomotion capacity of the patients. The traditional diagnosis of knee OA could not obtain the accutate kinematics data from the affected joints during the gait cycle, which is essential for the optimal design of convervative treatment options, such as knee braces for these patients. Objective: The current study using a combined experimental and computational approach to the analysis of the joint kinematics and muscle pattern during the gait cycle in patients suffering from knee OA; and our approach should provide specific characteristics of the knee for the brace design of these patients. Method: Fifteen knee OA patients participated this experiment, in which the electromyography was used to acquire the activation of major lower limb muscles and the motion of the hip, knee and ankle was captured during gait cycle. The motion data was used to build the personalized musoskeletal model of individual and the joint kinematics were obtained and compared against those of the normal subjects. Results: During the gait cycle, the knee joints of the OA patients shows an increased flexion motion upon the weight acceptance, but lack of extension motion during the mid-stance phase, and decreased swing speed at the early swing phase. The joint angle curve of hip and the ankle joints exhibit less rangeability. Knee OA patient's quadriceps and hamstring's muscles showed significantly longer activity duration during the gait cycle; at the beginning of stance phase the quadriceps and hamstring's muscles of patients performed more activation to stiff the knee joint and reduce the bending of knee. During the swing phase, the medial gastrocnemius of patients show much higher activation level compared with normal subjects.