Sports Medicine

Labral tear and Instability

As the most mobile joint in the body, the shoulder is capable of a wide range of motion in various planes. This versatility enables athletes to use the arm for everything from throwing a baseball to catching a football to bowling. However, this range of motion makes the shoulder joint more susceptible to dislocations, and athletes tend to be at much higher risk for incidences of joint instability. Most commonly, the rim of specialized cartilage (similar to that found in the nose and ears) known as the labrum can become damaged and a labral tear can develop, leading to further instability. The labrum surrounds the outer portion of the cup side of the shoulder joint and helps to deepen the cup and stabilize the humerus in its “socket”. When the shoulder is dislocated, the labrum can be stretched out or torn and is no longer able to stabilize the joint as effectively. Treatment is tailored to the specific pathology of each injury.

Labral tear- healthy labrum
An intact glenoid labrum and biceps tendon.
Labral Tears- SLAP

SLAP tears are a specific type of labral tear in which the top portion becomes torn from the front to the back (Superior Larum Anterior to Posterior). Since one  of the 2 biceps tendons originates from the labrum, it may also become torn with a SLAP tear.

This type of labral tear frequently leads to pain and instability, but many people lead active, pain free lifestyles even with a SLAP tear. However, tears to this portion of the labrum tend to have much greater impacts on throwing mechanics and performance in overhead athletes.

Labral tear- SLAP
A SLAP tear without biceps tendon involvement

Some may be treated non-operatively with an injection to relieve pain combined with physical therapy focused on stabilizing the shoulder and strengthening both the muscles within the shoulder joint and around the shoulder blade. Other cases may require arthroscopic surgery in which a small camera and several tools are inserted into portals in your shoulder. Bio-absorbable anchors are then screwed into the edge of the cup side of the joint and used to fasten the torn labrum back in its proper anatomic position. Patients typically wear a sling for 4-6 weeks and begin returning to pre-operative activity around 3-6 months post-operatively.

Anterior Instability

Anterior Instability refers to a propensity of the arm bone (humerus) to slip towards the front of the body and over the edge of the cup side of the joint (glenoid), leading to a subluxation or dislocation. These events can damage both the labrum and the glenoid. Damage to these structures puts the patient at much greater risk for subsequent dislocations. Anterior instability is a fairly complex problem that can arise from both bony and soft tissue structures on both the glenoid and the humerus.

When the labrum is torn towards the front and avulses a small portion of the glenoid with it, the tear is known as a bony Bankart lesion, and surgery similar to a SLAP repair (discussed above) can successfully repair the torn portion of the labrum and restore stability to the shoulder.

However, repeated dislocations can cause the front part of the glenoid to erode in addition to the labral tear, and additional steps may be necessary to restore a normally functioning shoulder joint. One of the most common options is the Latarjet procedure. This procedure uses an open approach as opposed to arthroscopic, and involves taking a small piece of bone from the shoulder and moving it to the front of the glenoid, filling in the damaged portion and making the shoulder far less likely to dislocate in the future.

Labral tear- Bankart repair
Before and after an anterior Bankart repair

Anterior instability may also be caused by damage to the humeral side of the joint. When the shoulder dislocates, the humerus is pressed against the glenoid, causing an indentation into the bony surface of the humerus. This deformity is known as a Hill Sach’s lesion, and can lead to further instability. If the Hill Sach’s lesion is large enough, it may require a number of different treatment options depending on the size of the lesion. Damage to the soft tissue structures surrounding the humerus may also lead to instability and require treatment.

The interaction between a Hill-Sachs lesion and a Bankart tear

These factors alone demonstrate the complexities of treating anterior instability. At The Shoulder and Elbow Center, we employ a scientific approach regarding all of the possible pathologies leading to instability, and utilize a number of algorithms and calculations pertaining to the specific structural abnormalities of each patient. This provides a highly specialized plan of care for each patient and ensures optimal outcomes, allowing athletes to return to competition without fear of further instability.

Another option for the treatment of instability, a capsular plication, can restore stability to the shoulder joint. The procedure differs from a standard labral repair because it involves tightening the redundancy in the loose capsule. See the video below to watch Dr. Spencer perform the procedure on a patient with posterior instability.

Research and Patient Education