Anatomy of the Shoulder
The shoulder is the most free-moving joint in the body. It is composed of three bones: the humerus (upper arm), the scapula (shoulder blade), and the clavicle (collar bone). The humerus and scapula form a ball and socket joint, but the socket is very shallow in the shoulder.
The head of the upper arm bone is much larger than the socket, like a golf ball sitting on a tee. This bony anatomy allows free motion but does not give the shoulder inherent stability. The glenoid labrum is a cartilage rim attached to the shoulder socket that deepens the socket for a better fit and to provide the needed stability. The labrum also serves as an attachment site for several ligaments.
Types of Labral Tears
Tears can be located either above (superior) or below (inferior) the middle of the glenoid socket. A SLAP lesion (superior labrum, anterior to posterior) is a tear of the rim above the middle of the socket that may also involve the biceps tendon. There are many different variations of SLAP tears, and the treatment differs based on the type. Inferior tears can occur in the front (anterior-inferior) or back (posterior-inferior), and are often associated with certain types of instability of the shoulder. Sometimes these tears may occur together, and in severe cases a 360 degree detachment of the labrum from the glenoid may be seen.
Causes of a Glenoid Labral Tear
There are two major causes of injury to the glenoid labrum: repetitive motion and acute trauma. Repetitive motion tears are often seen in throwing or other overhead athletes and weightlifters, while acute tears may be caused by:
- Direct contact blow to the shoulder
- A sudden jerk or pull of the arm
- Shoulder dislocation
- Falling on an outstretched arm
- Lifting a heavy object
Labral tears can also be degenerative, which means that the tissue has simply worn out over time.
Symtoms of a Glenoid Labral Tear
Symptoms of injury to the glenoid labrum include:
- Pain, especially with overhead arm motions
- Catching or grinding in the shoulder
- Sense of shoulder instability
- Decreased range of motion
- Loss of strength
Your physician will take a history and perform a physical exam, checking for range of motion, stability, and pain. Specific physical exam tests may be used to help diagnose a tear in the labrum. X-rays or other imaging tests may be used to see if there are other reasons for your pain. A special MRI called an MR-arthrogram is often used to confirm a diagnosis of labral tear. The MR-arthrogram involves an intra-articular injection of contrast material (gadolinium) immediately before the MRI study to help highlight the labral structures and show tears with greater accuracy.
Many labral tears, especially in older patients, can be treated non-operatively. Anti-inflammatory medications, injections, and physical therapy focused on shoulder motion and strength are the main non-operative treatment measures. Activity modification, if possible, is also helpful by avoiding the overhead activities that cause symptoms.
Tears that do not respond to non-operative management may need surgery. This can generally be performed through shoulder arthroscopy. In younger patients, tears are usually repaired, if possible, by reattaching the labrum back to the bony shoulder socket with devices called suture anchors. If shoulder instability is also present, reattachment or plication (pleating) of the shoulder ligaments and capsule is performed as well to restore stability.
In older patients, repair of a labral tear is not always the best option and sometimes debridement (trimming) of the tears is performed. For SLAP tears the biceps tendon, which attaches nearby on the superior labrum, may be cut and reattached to the bone in a different position. For lower demand individuals, the biceps tendon may simply be released without reattachment.
As with any surgery, infection is always a risk however the percentages are quite low with shoulder arthroscopy. With labral surgery specifically, post-operative shoulder stiffness is the most common complication. Re-tears of the labrum or failure of the repair is also a concern. Physical therapy following surgery is designed to balance the risk of stiffness with the risk of re-injury and hopefully minimize both. Less common complication of labral surgery include damage to nerves around the shoulder and over-tightening of the ligaments leading to loss of motion and possibly osteoarthritis down the road.
After surgery the shoulder will be in a sling for about four weeks. It is very important during this time to follow your surgeon’s instructions on immobilization, and not to jump into too much activity too soon. Many failures are a result of non-compliance in which the patient became too aggressive with therapy before the labrum heals back into place.
Once cleared for therapy by the physician, you will typically begin with gentle range-of-motion exercises before moving into full motion and flexibility exercises. Strengthening exercises can typically begin 6-8 weeks after surgery, followed by sport-specific activities at 2-3 months. Full recovery for most tears can be expected in 3 to 4 months.
- I’m not an athlete and I don’t lift heavy things, do I need surgery for my labral tear?
It depends on many factors such as the type of tear, your age, and activity level. Some labral tears that are not associated with any shoulder instability may not need surgical attention. If your symptoms can be controlled with medications, exercises, and activity modification then you can likely avoid surgery.
- Will I be able to return to throwing/pitching after labral repair surgery?
Assuming that a durable repair of the tear can be achieved, with the proper rehabilitation after surgery most throwers will be able to return to their sport. An excellent example is QB Drew Brees for the New Orleans Saints, who had a repair of a very large (360 degree) tear of the labrum early in his NFL career and is still one of the top passers in the league.
- If my tear involves the biceps tendon and it has to be released, will I still be able to lift things with my arm?
The biceps muscle in the arm has two tendon that extend toward the shoulder. One, the long head, travels inside the joint and attaches on the superior labrum. The other, the short head, attaches on the coracoid process on the front of the shoulder blade. If the long head is released and reattached (biceps tenodesis), most patients do not see a noticeable loss of strength in the arm. Even if it is released and not reattached, only small decreases in forearm supination strength and even smaller decreases in elbow flexion strength can be seen.
- I was told that I have a Bankart tear. Is that different from a labral tear?
A Bankart tear is a specific type of anterior labral tear that usually results from a shoulder dislocation. It can also involve a piece of bone from the anterior-inferior glenoid (called a bony Bankart lesion) along with the labral tear.
If you have more questions, please call my office at 502-394-6341.