投球時の外反ストレス推定方法：映像を用いた自動解析の予備研究

抄録

In baseball, pitchers, at a wide range of levels are suffering from severe elbow injuries. To reduce the risk of developing elbow injuries, pitchers should find and grasp technical tips for minimizing the valgus stress. This technical improvement is not easily done primarily due to that the pitcher cannot self-recognize how large the valgus stress applied to the elbow joint during pitching. In this preliminary report, we present our first attempt to find a way to automatically estimate elbow joint valgus stress from the video-images taken by a cell phone. Pitching motions of four adults were recorded by a cell phone and a motion capture system simultaneously and the elbow valgus stress of each pitch was computed for both data sets with an inverse dynamics approach. The comparisons of the corresponding two sets of valgus stresses showed that the average difference was 14.75%. We also found that the error rate varies among the three pitches of the same pitcher. In the future, as a further improvement in accuracy, we plan to analyze the factors of the pitching form that increase the error rate. We also plan to verify the accuracy of various pitchers with different heights, weights and baseball experiences.