Kinematic MRI of the Normal Shoulder Using a Specially Designed Positioning Device

OBJECTIVES: The objective of this study was to determine the normal patterns of the normal glenohumeral joint by kinematic MRI with a special positioning device. METHODS: Ten healthy volunteers were examined using an open MRI system. Axial three-dimensional gradient-echo images were obtained through the glenohumeral joint in the transverse axial plane by 30 degrees increments from external rotation to internal rotation. RESULTS: The free margins of the anterior labrum (40%) and the posterior labrum (10%) were seen to be slightly mobile. Although the anterior labrum showed increased signal intensity (20%), no signal intensity changes occurred in the posterior labrum. Most of the anterior labrum was not triangular in internal rotation. The anterior joint capsule showed changes in shape (60%) in neutral and internal rotation. CONCLUSIONS: Kinematic MRI can provide information on the labrocapsular ligamentous complex without the need for intraarticular injection of a contrast agent.