Modeling of Pro-supination for Forearm Skeleton Based on MRI ⋆

The continuous passive motion (CPM) device we developed for the elbow joint implements pro-supination of the forearm naturally accompanying flexion and extension of the elbow joint. As the method of making the curative effect due to accompanying pro-supination clear, the range of motion (ROM) of the forearm skeleton are estimated by using of the prosupination model of the forearm skeleton. As the pro-supination model of the forearm skeleton, there are the models Fick and others and Kecskemethy and others proposed. But, hypothesis is set in regard to the link length of the model and the rotation axis of the forearm. So, in the case of pro-supination of the forearm, it is thought that mismatch happens between the forearm skeletal model and the forearm skeleton. In this paper, by analyzing magnetic resonance imaging (MRI) of the forearm, we proposed the newer forearm skeletal model based on the biomechanics.