What is a labral tear?
The shoulder joint is composed of the upper arm bone (humerus) and the shoulder blade (scapula). This joint allows a lot of mobility based upon its ball-and-socket (enarthrodial) construction at the cost of boney stability. The labrum is a piece of rubbery tissue (fibrocartilage) that surrounds the outer rim of the socket of the shoulder blade. This tissue helps to hold the ball of the arm in place and provide stability to a naturally unstable joint. When this cartilage is torn, it is called a labral tear.
Who gets labral tears?
In young people, labral tears can be caused by an acute injury or repetitive overuse. The two most common types of labral tears are called Bankart tears and SLAP (Superior Labrum from Anterior to Posterior) tears. Bankart tears are often associated with shoulder dislocations or trauma that knocks the humerus against the socket and labrum, such as Football linemen or Weightlifters. SLAP tears occur from overhead throwing or hitting motions as seen in Baseball pitchers and Volleyball.
What are the signs and symptoms of a labral tear?
Labral tears are often associated with generalized deep shoulder pain and difficulty moving the arm, particularly overhead. Other symptoms can be mechanical in nature such as catching, locking, and popping with certain shoulder movements. In large tears, apprehension may be felt in certain positions for fear of dislocation. A sensation of subluxation or clunk in the shoulder with certain motions could also suggest a labral tear. SLAP tears can cause pain in the front portion of the shoulder.
How are labral tears diagnosed?
A good history and physical exam can cause suspicion of a labral tear. Further evaluation of a suspected tear typically do require special imaging called MR arthrography. This type of study involves injecting dye into the shoulder joint and scanning to check for any leaks of the dye that would occur with a labral tear. An MRI without this dye may only be 50-70% sensitive for small labral tears and is not recommended. Definitively, however, labral tears can be confirmed through arthroscopy.
How are labral tears treated?
Labral tears are initially best treated conservatively with rest, activity modification, anti-inflammatory medication, and sometimes cortisone injections. This process is then followed by physical therapy that allows proper stretching and strengthening of the rotator cuff muscles that hold the shoulder joint together. If conservative management fails, surgical intervention may be required to repair the tear.
How are labral tears prevented?
Activities performed with the arms raised over-head significantly increase the chances of developing a labral tear. To reduce the risk of causing a tear, strengthening the muscles that surround the shoulder joint can aid in protecting from labral tears. Further, activity modification with proper body mechanics can reduce the chance of developing a tear.
By Michael Slack and Mo Mortazavi, MD