The purpose of this study is to analyses the three dimensional movement of the glenoid and the gleno-humeral joint in the habitual posterior dislocation of the shoulder.
5 male and 6 female patients with habitual posterior dislocation were examined.
The magnetic sensor system was used for measuring. The magnetic field generating source was fixed to the sternum, and sensors were fixed to the lateral epicondyle of the humerus and to the spina scapulae.
Elevation was measured in the sagittal plane, the scapular plane and the frontal plane.
The elevation time was 5 seconds.
The gleno-humeral joint with inferior instability decreased in the elevation angle at the initial stage of movement. The glenoid in the sagittal plane did not face the plane of flexion during the initial 90°. Incoordination of the scapula and the humerus was one of the causes of posterior shoulder instability.
