Classification

Anterior Dislocations

The head of the humerus lies anterior to the glenoid fossa; there may be significant disruption of the surrounding soft tissues.

Subtype position of the humeral head

  1. Subcoracoid – anterior to the glenoid fossa but inferior to the coracoid process.
  2. Subglenoid – anterior and inferior to the glenoid fossa
  3. Subclavicular – anterior to the glenoid fossa and medial to the coracoid process (inferior to clavicle)
  4. Intrathoracic – antero-medial to the glenoid fossa between the ribs

Posterior dislocations

In posterior dislocations, the head of the humerus lies posterior to the glenoid fossa.

Subtype position of the head

  1. Subacromial – Beneath acromion (most common)
  2. Subglenoid – Beneath glenoid
  3. Subspinous – Medial to acromion and beneath the spine/the scapula

Inferior dislocations (luxatio erecta)

In this rare injury, the head of the humerus sits just beneath the glenoid fossa.

Explanation

Based on the direction of instability, glenohumeral dislocations have been classified as anterior, posterior and inferior.

Figures


Anterior dislocation of the shoulder


Inferior dislocation of the shoulder after a car accident. Image courtesy of James Heilman, MD

Reference(s)

Provide the citation for the landmark article and recent review articles describing the classification

Attachments:


Dislocate1.PNG (image/png)


Dislocate2.JPG (image/jpeg)