Focal cortical bone loss at the inferior aspect of the glenoid: A new radiographic sign of anterior shoulder instability.

Abstract

This report describes the detection of localized cortical bone loss at the inferior glenoid with the use of anteroposterior radiographs of the shoulder. This bone loss was noticed in two of 100 patients who had recurrent anterior instability of traumatic origin. Double-contrast arthrography and the operative findings disclosed that this lesion coincided anatomically with the scapular insertion of the detached anterior capsule. A survey of 544 radiographs from patients who had various other shoulder disorders did not detect any similar bony changes. Thus this pattern of bone loss, although small and uncommon, appears to be a new radiographic sign of damage to the anterior capsular mechanism.