Ankle Joint Stretching Device by Using Tension Rod Structure for Self Rehabilitation

摘要

In this paper, we proposed a platform-based ankle joint stretching device which is intended for self-rehabilitation by combining tension rod structure for the fixing function and leg lifting mechanism for the adjustment function. Generally, physical therapists treat their patients to prevent contracture and to improve walking function, but sufficient rehabilitation therapy cannot be performed due to demanding labor-tasks. Therefore rehabilitation robots have been proposed in order to help physical therapist to treat their patients. However, patients require transfer assistance by caregivers to use the machine therapy, which assistance causes back pain of caregivers. In addition, patients have to adjust the machine to their particular body form in order to effective stretching. In proposed tension rod structure, it consists of a pantograph jack and a spring caster in the device, and able to change the fixon-fix state to patient's sitting chair, which makes the device unnecessary transfer assistant. Furthermore, the structure has simple adjustment function for the length of patient's leg by combining the leg lifting mechanism using linear actuator. In experiment, we confirmed that the positional relationship between the rotation axis of the device and the ankle joint position was stabilized within (σx, σy)=(±2.4, ±2.5) mm during ankle dorsiflexion stretching in fix state of the device. Our proposed mechanisms which reduce labor tasks before/after treatment will lead to development of the stretching devices that the patients can use themselves.