DISLOCATION SHOULDER

Young population is more affected by shoulder instability, which can be anyway divided in two groupa, constitutional and traumatic, sometimes associated. The first one is due to a generalized ligamentous laxity causing the slipping of the humeral head, exceeding normal articular tracking.

The shoulder dislocation caused by trauma is more common, very painful, and requires an immediate reduction: te classic mechanism of injury is the association of the movement of abduction and external rotation (gesture of the pitcher).

In traumatic form, the capsuloligamentous complex called glenoid labrum and in particular the glenohumeral ligaments medium and inferior are detached from the bone and elongated (Bankart lesion). The arthroscopic surgical indication is classical in recurrent dislocations. One must always keep in mind, however, the number of episodes, the age (if young, higher percentage of recurrence), sport and work, quality of the tissue to be repaired: an index number can be given to every patient, from the sum of the different values assigned to the prognostic factors mentioned above.

The advantages of the arthroscopic treatment of shoulder dislocation (we adopt in the great majority of cases, after the second episode of dislocation) are:

1 Minimal surgical trauma.

2 Improved evidence of anatomical lesion and therefore better opportunity to repair it.

3 Minimum aesthetic damage (scarring a few millimeters long).

4 Faster recovery faster, less painful and simpler.

The aim of surgery is to restore the continuity of the capsule (‘capsular-labral complex’) reinserting it to the bone and obtaining an optimal capsular suture in order to control the humeral head during joint movements.

Open surgical technique according Latarjet

This technique involves the separation (osteotomy) of the coracoid base resecting the coracoacromial acromial ligament and the reinsertion of this bone apophysis to the scapular glenoid process in an anterior sub-equatorial position (ie anterior and inferior to the glenoid, continuing in an ideal way in this direction the articular surface of the scapula and thus obtaining a more extended articular surface in order to support the head of the humerus).

The technique Latarjet is normally performed through a small incision with mini open technique, even if nowadays a few arthroscopic techniques are developing. The specific indication for the technique of Latarjet is the chronic instability (ie dislocations repeated over time) in which there is a loss of bone tissue and articular cartilage bigger than 20% in the region of the lower anterior glenoid surface, or in cases of association of bone defect of the glenoid less severe but with a great deformity of the humeral head secondary to the repeated dislocations (the so-called Hill Sachs lesion); this technique is also indicated in failures of arthroscopic stabilization of the shoulder, as well as in recurrent dislocation of the shoulder of the epileptic patient, and in shoulder prosthesis instability.

The advantage of the technique of Latarjet in respect to other surgical techniques is to restore the missing bone tissue of the glenoid and in the same time to stabilize actively the shoulder with the so called common tendon. An experienced surgeon will be able to successfully perform this technique through an incision a few centimeters by not fully detaching the tendon of the subscapularis, which can be splitted, and passing the bine resected through the muscle and fixing it to the glenoid rim. This results in a more rapid healing and an excellent clinical results.