J027033 Development of an Above-Knee Prosthesis for Swimming Focused on Ankle Joint Motion

Abstract

The objective of this study were to develop an above-knee prosthesis focused on the ankle joint motion, and to confirm the usefulness of the developed prosthesis. Based on the problems of the previous prototype for prosthesis, an improved prosthesis was developed. The ankle joint of the prosthesis had a spring which enabled the passive joint motion due to the fluid force acting on the foot. An experiment with a subject swimmer attaching the developed prosthesis was conducted. The joint angles during flutter kick in the sagittal plane were measured. The time for 25m crawl swimming was recorded and questionnaire evaluation was also conducted. Four types of the spring constant (rigid, strong, weak and free) were tested. It was observed that the ankle joint motion changed according to the change of the spring constant. It was also found that there was the spring constant most comfortable for the subject swimmer. This result was supported by the experimental result that the swimming with the most comfortable spring brought the fastests wimming speed.