Shoulder Dislocations

About Shoulder Dislocations

The shoulder joint has the greatest mobility of any joint in the body. However, this increased mobility comes with the cost of recurrent instability. Instability of the shoulder joint may be a result of a frank dislocation from a traumatic event or slow and progressive instability from continuous trauma. Ligaments and the soft tissues (labrum) around the shoulder joint are mainly responsible for affording the shoulder static stability (stability during rest). The rotator cuff muscles, the ligaments, and the labrum are all responsible for dynamic stability (added stability during shoulder motion) of the shoulder joint. Instability is diagnosed by physical examination, and lesions are confirmed by MRI arthrogram (dye injected inside the shoulder joint prior to obtaining the MRI).

Traumatic Instability usually involves rupture of the labrum from the glenoid bone. This takes the tension off the ligaments that are attached to the labrum and usually cause anterior instability. When dislocation occurs in young and active individuals, recurrent instability is very common. Treatment initially is aimed at reducing inflammation and increasing motion slowly and safely. Since the static restraints to shoulder stability are compromised (torn ligaments and labrum) therapy is directed towards the rotator cuff muscles to add dynamic stability. If therapy fails and recurrent instability occurs, then surgical stabilization of the shoulder joints is an excellent option. In the past, open surgery has been the preferred treatment for shoulder dislocation. Although successful, open surgery has many disadvantages such as a large scar, loss of motion, and large dissection requiring detachment of healthy muscles and ligaments to gain access to the shoulder joint. Arthroscopic reconstruction affords the same surgical concepts without those disadvantages. This involves placing metallic or absorbable suture anchors inside the bone and repairing the labrum onto the glenoid bone using small arthroscopic cameras and instruments. The ligaments can be tightened to allow increased stability (also called capsular shift). Patients wear a sling for four weeks and return to non-contact sports in three months and contact sports in six months.