Posterior Shoulder Stabilization

What is Posterior Shoulder Stabilization?

Shoulder stabilization involves procedures to prevent dislocation of the ball and socket joint in the shoulder. The ball portion of this joint is formed by the end of the upper arm bone (humerus) and the socket is formed by a cavity at the side of the shoulder blade called the glenoid. The shoulder joint is stabilized by muscles, tendons, ligaments, the joint capsule and a rim of cartilage (labrum) bordering the glenoid. Damage to these structures can cause the shoulder to become unstable and dislocate. Most dislocations involve the humeral head slipping forward out of the joint (anterior dislocation) but dislocations can also occur in a backward direction (posterior dislocation). Posterior dislocations account for only about 2% to 5% of shoulder dislocations and is often misdiagnosed.

Causes of Posterior Shoulder Dislocation

Posterior shoulder dislocation may be associated with

• Acute injuries (trauma)
• Overuse injuries causing microtrauma and instability
• Weightlifting and overhead athletics
• Stretching of the capsule
• Seizures or electric shock

Symptoms of Posterior Shoulder Dislocation

Posterior shoulder dislocation is usually associated with pain while pushing. Unlike anterior instability, pain is more significant than instability.

Indications for Posterior Shoulder Stabilization

Posterior shoulder stabilization is recommended for shoulder instability with frequent posterior dislocations of the shoulder joint.

Procedures for Posterior Shoulder Stabilization

For acute traumatic dislocations, the shoulder is reduced back into position and immobilized with the shoulder joint in an externally rotated position for 4 to 6 weeks.

Your doctor will first recommend conservative treatment options such as medications, rest, ice application and physical therapy to improve shoulder stability. If this fails, shoulder stabilization surgery may be recommended to improve stability and function to the shoulder joint. Posterior shoulder stabilization can be performed with open surgery or with the help of an arthroscope using small incisions.

Arthroscopy is a minimally invasive surgery and is performed through tiny incisions (portals) around the joint area. Through one of the incisions, an arthroscope (small fiber-optic viewing instrument) is passed. A television camera attached to the arthroscope displays the images of the inside of the joint on the television monitor, which allows your surgeon to view the cartilage, ligaments and the rotator cuff while performing the procedure. A sterile saline solution is pumped into the joint to expand it and provide a clearer view to the surgeon. Depending on your condition, your surgeon may perform one of the following procedures:

• Posterior labral repair
• Posterior capsular shift
• Posterior glenoid osteotomy
• Transfer of the subscapularis
• Transfer of the lesser tuberosity
• Hemiarthroplasty
• Total shoulder replacement

Recovery Following Posterior Shoulder Stabilization

Following surgery your arm will be immobilized. Early range of motion and strengthening exercises are recommended. You will have certain activity limitations. Strenuous activity such as sports may be performed in 6 months.

Risks associated with Posterior Shoulder Stabilization

As with any procedure, posterior stabilization surgery may be associated with certain complications including:

• Stiffness
• Recurrence
• Nerve injury
• Anterior instability
• Shoulder impingement