The shoulder joint is a ball and socket joint. A ball at the top of the upper arm bone (the humerus) fits neatly into a socket, called the glenoid, which is part of the shoulder blade (scapula). The labrum is a ring of fibrous cartilage surrounding the glenoid, which helps in stabilising the shoulder joint. The capsule and ligaments attach to the labrum and together these form the important static restraints of the shoulder. The biceps tendon is attached inside the shoulder joint at the superior labrum of the joint. The biceps tendon is a long cord-like structure that attaches the biceps muscle to the shoulder and also helps to stabilise the joint.
Shoulder Labral Tears
Traumatic injury to the shoulder or overuse of the shoulder can cause a labral tear. In addition, the ageing process may weaken the labrum, leading to labral injury secondary to wear and tear. Where damage to the labrum occurs will be determined by the direction of force applied to the shoulder and where the arm is positioned at the time. This may be anterior (front), posterior (back), superior (SLAP), or more widespread.
Symptoms of Shoulder Labral Tears
A shoulder labral tear injury can cause symptoms such as pain, a catching or locking sensation, decreased range of motion and weakness, and joint instability.
Types of Shoulder Labral Tears
The most common types of labral tears include:
- SLAP tear: The term SLAP (superior–labrum anterior-posterior) refers to an injury of the superior labrum of the shoulder at the attachment of the biceps tendon.
- Bankart tear: A Bankart tear is an injury to the labrum, usually at the front of the shoulder, most commonly due to a traumatic instability event. This may lead to recurrent dislocations of the shoulder.
- Posterior labrum tear: This type of labrum tear is rare, but may be caused by a posteriorly directed force across the shoulder. Most commonly posterior labral tears result in pain and mechanical symptoms rather than recurrent instability of the shoulder, and are worse with posterior loading of the shoulder (for example with bench press).
Diagnosis of Shoulder Labral Tears
Your doctor may suspect a labral tear based on your symptoms and medical history. Several physical tests will be performed to evaluate the range of motion and stability of your shoulder. X-rays, computed tomography (CT) scan or magnetic resonance imaging (MRI) scan, sometimes with a contrast medium, may be ordered to determine the presence of tears. Diagnosis of a labral tear can also be confirmed through shoulder arthroscopy.
Conservative Treatment of Shoulder Labral Tears
Your doctor may initially suggest conservative approaches such as anti-inflammatory medications and advise rest to relieve symptoms. Rehabilitation exercises may be recommended to strengthen the rotator cuff muscles. If the symptoms do not resolve with these conservative measures, your doctor may recommend surgery.
Surgical Treatment of Shoulder Labral Tears
During arthroscopic surgery for a SLAP tear, your surgeon examines the labrum and the biceps tendon attachment. If the damage is confined to the labrum without involving the tendon, then the torn flap of the labrum may be removed. In cases where the tendon is also involved or if there is a detachment of the biceps tendon, then suture anchors may be used be used to repair and reattach the tendon, or the bicep tendon may be cut and reattached outside of the shoulder joint (biceps tenodesis).
Bankart lesions and other labral tears around the shoulder are repaired by an arthroscopic Bankart operation. In this procedure, the Bankart tear is repaired by reattaching the labrum and the capsule to the anterior margin of the glenoid cavity. Your surgeon makes a few small incisions around the joint. Through one incision, an arthroscope is inserted into the shoulder to visualise the inside of the shoulder joint. Other surgical instruments are inserted through the other incisions to re-attach the labrum to the glenoid with the help of sutures or anchoring devices. The arthroscope and surgical instruments are removed, and the incisions are closed.
Postoperative Care for Shoulder Labrum Reconstruction
Following the surgery, your shoulder is immobilised with a sling, usually for the first 4 to 6 weeks. To control pain and swelling, your physical therapist may use ice, electrical stimulation, massage therapy, and other hands-on treatments. Passive range of motion exercises are also initiated in the postoperative phase. Active range of motion exercises is started about 6 weeks after the repair to regain your shoulder movement, with strengthening exercises beginning at about 10 weeks. Athletes can return to sports in about four to six months.