Abstract
The shoulder is very complex because it consists of the Sternoclavicular joint, Acromioclavicular joint and Glenohumeral joint. Therefore, the kinetic analysis of the shoulder was difficult. In this research group, dynamic analysis was made possible by applying the method of dynamic analysis of 6 degrees of freedom using original image matching method. This study aimed to comparison of normal shoulder and rotator cuff injury in motion analysis of shoulder. The subjects were ten healthy participants and five patients who damaged a rotator cuff. We evaluated the shoulder kinematics during dynamic scapular plane full abduction and full external rotation. In result, in the scapular plane external rotation, the largest displacement was an internal/external rotation in the average angle of rotation of a normal, patients each 113.6±11.1 deg, 66.3±13.6deg. In the scapular plane full abduction, the largest displacement was an adduction/abduction rotation in the average angle of rotation of a normal, patients each 97.9±3.0deg，74.8± 23.8deg. In the scapular plane external rotation, the value of a superior/inferior of normal and patients were each 3.2±1.2 mm, 1.5±0.7 mm. In the scapular plane full abduction, the value of a superior/inferior of normal and patients were each 4.1±1.8 mm, 2.9±0.9 mm. Our results showed that we were able to seen the characteristic of displacement of the scapular plane external rotation and full abduction in normal and patients. In the future, we want to obtain a new understanding by analyzing the shoulder after Arthroscopic Rotator cuff repair operation.
