First-time anterior shoulder dislocation: Decision-making and surgical techniques

Introduction: The glenohumeral joint has the largest range of motion of any joint, leaving it susceptible to instability.

Pathophysiology: Instability can lead to a wide variety of injuries to the shoulder, with labral tears being the most common.

Work-up: Specific physical exam maneuvers and imaging tests can help diagnose instability and discern concomitant injury patterns. Special attention must be paid to quantifying bone loss from the glenoid and/or the humeral head.

Treatment: There are a variety of methods to reduce a dislocated shoulder in an emergent setting. Controversy exists as to the role of non-operative treatment in the young, active population, and the role of immobilization. Operative treatment may often involve soft tissue procedures or bone block procedures for bone loss and revisions. These procedures can be done open or arthroscopically.

Shoulder dislocations almost always cause injury to the shoulder—usually a labral tear.

Bone loss must be identified and quantified. If not addressed appropriately by the chosen surgical technique, it is a major risk factor for recurrence. Significant bone loss is a contraindication for a soft tissue repair.

There are many ways to classify “significant” bone loss, including an inverted, pear-shaped glenoid, an engaging Hill-Sachs lesion, glenoid width loss greater or equal to 13.5%, an off-track glenoid lesion, or an ISI score over 6.

A Bankart repair involves repairing the torn anteroinferior labrum in an effort to reconstitute the labral bumper and re-tension the capsuloligamentous structures that insert on the labrum.

There are a number of bone block procedure, of which the Latarjet is one of the most commonly employed. In this procedure, which can be done open or arthroscopically, the entire coracoid distal to the coracoclavicular ligaments is fixed to the anterior glenoid rim. This augments the deficient glenoid bone and the conjoint tendon and subscapularis split help support the deficient antero-inferior capsule.

Labral repair:

• Portal placement in good position for visualization and anchor placement

• Full preparation of glenoid to bleeding bone

• Sufficient subperiosteal labral release

• Anchors slightly on glenoid face to reconstitute the labral “bumper.”

Latarjet:

• Can be done open or arthroscopically

• Proceed with caution when osteotomizing the coracoid due to the close proximity of neurovascular structures.

• Use two bicortical screws to secure the coracoid to the glenoid

Labral repair:

• Insufficient exam under anesthesia or missing concomitant injury with an inadequate diagnostic arthroscopy.

• Failing to address significant bone loss with a soft tissue procedure alone.

Latarjet:

• Poor graft placement on the glenoid can fail to improve stability and lead to degenerative changes to the glenohumeral joint.

• Prominent hardware can be irritating to the subscapularis.

• Neurovascular complication, though rare, can be catastrophic.