What is the labrum?
The labrum is a tissue that encircles the socket of the shoulder (glenoid). It extends the size of the socket to match it to the humeral head (ball of the shoulder). It is elastic and allows the shoulder to move with more freedom than if the bone was greater in size than the socket. The labrum’s soft tissue nature means it can tear for several reasons.
What types of labral tears are there and what is a superior labral tear?
The most common cause for a tear is after a shoulder dislocation when the most common site to tear is the anterior /inferior labrum. Posterior shoulder dislocations can result in posterior labral tears. Treatment of the labral tears in these scenarios involves treatment of the shoulder dislocation and stabilising the shoulder.
Tears can occur with age, as well as with wear and tear. As a shoulder moves around inside the socket, the tissue surrounding it can tear and become degenerate. Any ageing process causes this, and excessive use of the shoulder can be a factor. Smoking causes degeneration of the body in general, so can also be a factor. As with most structures, the ageing process is well tolerated and often is not the cause of major issues but is often an incidental finding during surgery performed for other reasons.
Finally, the third reason the labrum can tear relates to the biceps tendon. The biceps muscle has 2 origins: the short head which attaches to a bone outside the shoulder joint, and a long head which runs through the shoulder joint and attaches to the top of the other socket (the top of the labrum). With degeneration and rotator cuff problems, the biceps tendon itself can become inflamed and then eventually tear. In some situations, however, rather than biceps tearing, the labrum can pull away from the socket. With use of the biceps, this increases the tearing nature of the labrum, which is known as superior labral tear. It is often noted when people undertake excessive force using the shoulder, such as when throwing or lifting heavy weights.
It was discovered that these superior labral tears can be the cause of pain, as the biceps tendon continues to pull on the labrum, tearing it more and causing discomfort. This is known as a superior labral anterior posterior tear (SLAP tear). Any tear in this area of the labrum is known as a SLAP tear. The majority are degenerate tears and are incidental findings and do not warrant treatment. There are, however, others that are partial or fully torn away from the labrum and are associated with pain on use of the arm in which case this can then be treated in one of several ways.
In a younger patient, the labrum can be repaired back to the glenoid (socket) by abrading the bone that the labrum has pulled away from. An anchor, which has some sutures attached to it, is then inserted into the bone and used to tie the labrum back to the bone, allowing the bone to stick to the labrum. This is known as superior labral repair.
Another option is to release the biceps from the labrum, avoiding the pulling force of the biceps from the labrum. This is usually recommended in older patients and in this scenario the biceps can then be re-attached outside the shoulder, known as a biceps tenodesis, or left to retract which is known as biceps tenotomy.
The labral tear itself, if repaired, is treated as per a stabilisation procedure; the arm is placed in a sling for 6 weeks in total with pendulum exercises, and allowed to come out for dressing, axillary (armpit) care and exercises. Excessive straightening of the elbow or carrying weights with the arm straight is always avoided. The patient can then return to unrestricted duties at 3 months following surgery.
Can labral tears cause other issues?
Yes. Fluid can be forced under the area of the labral tear and form an outpouching of fluid (a cyst or Ganglion). Often the cyst does not cause symptoms, but those that occur in the back of the shoulder can push on the suprascapular nerve and lead to weakness of shoulder motion. The longer the nerve is compressed, the more it is damaged and less likely to recover. In these situations, the cyst and labral tear are recommended to be treated.
Treatment usually involves a shoulder arthroscopy to repair the labral tear. At the time of the keyhole surgery, the cyst is attempted to be decompressed and the fluid released. In most cases, repair of the labrum alone settles the cyst, but if the cyst can be decompressed this will help it recover.
Often it is not possible to release fluid, and thus if the cyst is pushing on a nerve and does not settle with the labral repair, then at a later date either a radiological drainage of the cyst is performed (day surgery where a radiologist places a needle into the cyst to release fluid) or a larger incision will need to be undertaken to excise the cyst (a bigger procedure which is rarely required).
How are labral tears diagnosed?
Usually labral tears are diagnosed from the patient’s story and symptoms, including pain on throwing and the sensation of something catching in their shoulder or in those associated with obvious dislocating episodes. Confirmation is made with an MRI scan which may be supplemented with intra-articular injection of dye to help form the diagnosis. As in all cases, treatment initially involves a course of physiotherapy to try to strengthen the muscles around the area, as well as education about avoiding particular movements that may cause symptoms. If however, the patient fails to respond to physiotherapy, then surgery is recommended.
How successful is surgical treatment of labral tears?
Not every case of pain in the shoulder relates to a superior labral tear, and given that often the degeneration in the labrum is an incidental finding, it may not always be the cause of symptoms. As such, one needs to be sure that the cause of pain relates to the labrum. When labral surgery is undertaken, other conditions that could also be causes of symptoms are often treated. The success of a labral repair on its own is probably lower, as in most cases the symptoms in the shoulder do not relate to superior labral tears. In those cases that specifically do cause symptoms, the operation can be very successful.
The important thing about assessing and treating a superior labral tear is to be aware of the other diagnoses and to be able to assess the patient appropriately.
Glenelg Orthopaedics specialise in shoulder surgery and can provide you with a thorough assessment, holistic advice, and customised treatment options for your situation.