On the Centrodes of Human Knee Joints using Photographic Method

摘要

The kinematics characteristics of the human knee joint can be represented by its centrodes. The sequential X-ray radiographs of the moving knee can provide the basic data for constructing the centrodes if the cost and side effects of radiation are not in concern. This paper provides an alternative method to construct the centrodes by using commercial digital camera to take the sequential pictures. In order to eliminate the undesired movements, a testing chair and a brace are specially designed. Two types of curve fitting methods are introduced to smooth the measured data of marked points on the lower leg. The differential method is applied to construct the centrodes of knee joint from the measured data. This paper provides a non-expensive, non-invasion, and non-radiation way to study the centrodes of human knee joint.