Image Based Question-66508

The most common sub-type of dislocation shown in the picture below is ?

A. Sub-coracoid.

B. Sub-glenoid.

C. Infra-clavicular.

D. Luxatio erecta.

Correct Answer » A Explanation

The dislocation shown in the picture above represents Anterior dislocation of shoulder.

Radiographic Subtypes:

Subcoracoid 

• most common type of anterior dislocation
• head of humerus is displaced anteriorly w/ respect to glenoid, & is inferior to
• coracoid process; 
  greater tuberosity is fixed on anterior glenoid rim; 
  neck of scapula is elevated and carried medially, positioning inferior tip of
• scapula in an abducted position; 

Subglenoid:         

• occurs in about 1/3 patients w/ anterior dislocation; 
• head of the humerus lies anterior and below the glenoid fossa; 
• the majority of these fractures are associated w/ either a greater tuberosity fracture or a fracture of the anteiror inferior glenoid rim; 

Subclavicular     

• head of the humerus lies medial to the coracoid process, just inferior to the lower border of the clavicle; 

 Inferior dislocation of the glenohumeral joint: luxatio erecta   

• humeral head lies inferior to glenoid fossa; 
•  superior aspect of articular surface of humeral head is directed inferiorly and is not in contact with the inferior glenoid rim;     
• severe soft tissue injuries or fractures about the proximal humerus occur with this dislocation;         
• look for avulsion of the supraspinatus, pectoralis major, or teres minor muscles and fractures of the greater tuberosity.