康复学报 (Dec 2022)
Biomechanical Gait Analysis in Children with Spastic Cerebral Palsy Using Foot Sole Model
Abstract
ObjectiveTo analyze the biomechanical characteristics of equinus and crouch gait in children with spastic cerebral palsy (CP) using the foot sole model, and to compare the differences with the gait biomechanical characteristics of normal developing children.MethodsGait data of 60 children with CP collected by the Biomechanics Laboratory of University of Auckland, New Zealand were selected and divided into normal developing group, equinus gait group and crouch gait group, with 20 cases in each group. A three-dimensional motion capture system was used to collect gait data. A static trial was first completed to calibrate the computerized model to each of the physical markers. In each test, the participant walked 10 meters at a self-selected pace along a 10-metre walkway. Three successful gait trials were obtained for each participant and the mean value was taken. The anteroposterior (AP) displacement, medial-lateral (ML) displacement and displacement slope of the plantar center of pressure (COP) were calculated and compared among the three groups. The distance between the center of pressure and the origin of foot sole coordinate system, and the ankle and knee lever arms and external moments in AP and ML directions at maximal propulsion were also compared among three groups.Results(1) Characteristics of plantar center of pressure progression: compared with the normal developing group, COP-AJC0 significantly increased in the equinus gait group and the crouch gait group (P<0.05). Compared with the equinus gait group, the crouch gait group had an increased COP-AJC0, a greater anterioposterior displacement, and a lower center of pressure displacement slope (P<0.05). (2) The ankle and knee lever arms and external moments: compared with the normal developing group, the crouch gait group and the equinus gait group had longer anteroposterior lever arms around the knee and ankle joints (P<0.05). Compared with the equinus gait group, the crouch gait group showed longer anteroposterior lever arms of the ankle (P<0.05). There were no significant differences in AP and ML external moments of ankle and knee joints in the three groups (P>0.05).ConclusionThe analysis of plantar center of pressure progression and lever arm characteristics of lower extremity joints based on the foot sole model can accurately and objectively reflect the biomechanical characteristics of gait in children with spastic cerebral palsy, which is recommended for clinical application.
