| Lower extremity motor dysfunction is extremely common in stroke and osteoarthritis patients.The study of human gait characteristics during walking with limited ankle dorsiflexion can provide a theoretical basis for the structural design and control strategy formulation of lower limb rehabilitation robots.At present,the research on gait characteristics of the ankle joint by domestic and foreign scholars mainly focuses on the changes of gait parameters under different environmental conditions.There is a lack of research on the changes in ankle motor function after limited range of motion and the way of compensation in the ankle caused by limited range of motion.In this paper,a walking gait experiment with limited dorsiflexion of the ankle joint was designed and carried out.The Pedar-X plantar pressure measurement system and the Vicon optical motion capture system were used to simultaneously collect the relevant gait parameters of the subjects,and to study the changes of the dominant ankle joint movement when the dorsiflexion was limited.This paper mainly carried out the following research work:(1)A straight walking gait test with restricted ankle dorsiflexion was designed.Three different working conditions were set up in the experiment: normal walking with unlimited position,walking with limited ankle dorsiflexion on the non-dominant side,and walking with limited dorsiflexion on the dominant side.Ten healthy adult subjects were selected(The dominant side of all subjects was right).Through plantar pressure measurement equipment and optical motion capture equipment,the gait parameters under different working conditions were collected,including time and space parameters,kinematic parameters and dynamic parameters.(2)The gait parameters of the foot and ankle joint were analyzed under the two working conditions of dorsiflexion limitation of the non-dominant side and dorsiflexion limitation of the dominant side.The pressure distribution coefficient Ep and the compensatory classification index Fc were proposed according to the difference of the impulse changes in each part of the plantar before and after the limitation in different subjects.The corresponding compensatory types under different working conditions were classified according to the difference of the compensatory mode of the subjects in dorsiflexion limitation of the ankle joint.(3)The similarities and differences of gait characteristics under different compensatory types were analyzed from the perspectives of gait temporal and spatial parameters,plantar pressure parameters and related kinematic and kinetic parameters.The main characteristics of different compensatory types were summarized.(4)Based on the results of the study,a series of pressure-reducing insole designs for the rehabilitation of patients with foot and ankle dysfunction were proposed.The designs were tailored to the foot and ankle compensatory characteristics of different compensatory types of groups,with the aim of reducing foot pressure,preventing strain injury during rehabilitation training,and improving walking stability.The conclusions obtained in this paper,such as the classification method of substitution types and different motion compensation characteristics under each substitution type,provide a basis for the structural design and control strategy development of lower limb exoskeleton rehabilitation robots in the engineering field;and provide guidance for the design and development of wearable products such as ankle rehabilitation aids.At the same time,the conclusions of this paper also have a certain reference role in the development of rehabilitation programs for patients with lower limb foot and ankle joint motor dysfunction in the medical rehabilitation field. |
