Radiographs for Posterior Shoulder Dislocation



- See:
   - Radiographic Studies for the Shoulder
   - Posterior Shoulder Dislocation

- Findings Seen on Specific Radiographic Views:
    - Axillary View:
         - reverse hill sachs lesion
    - AP of the Shoulder:
         - because humerus is internally rotated, the greater tuberosity will not be seen laterally, but rather will be seen directly in front of the humeral head;
         - subacromial dislocation:
               - posterior dislocation may leave humeral head in subacromial position so that humeral head lies behind the glenoid;
         - subglenoid:  head is beneath and behind the glenoid;
         - subspinous: in which head is medial to acromion & beneath spine of scapula;
         - loss of elliptical overlap:
               - on the standard AP of the shoulder (perpendicular to the body and not the scapula), the glenoid will be shown to have an oblique profile;
               - normally the humeral head will overlap the posterior portion of the obliquely profiled glenoid, but in the case of posterior dislocation, the normal overlap will not be present;
         - vacant glenoid sign:
               - refers to void seen in anterior half of glenoid fossa in posterior dislocations;
         - 6 mm rim sign:
               - space between anterior rim of glenoid & humeral head > 6 mm is highly suggestive of a posterior dislocation



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Monday, June 25, 2012 2:06 pm