SLAP stands for “superior labrum from anterior to posterior.” This type of shoulder labral tear occurs at the top (“superior”) of the glenoid labrum which forms a rubber like rim for the socket of the shoulder joint. In this type of injury, the tendon that attaches the biceps muscle to the shoulder may also tear. People who hit or throw balls really hard, like bowlers in cricket, volleyball players and other throwing athletes can get SLAP tears.
The shoulder is a ball-and-socket joint. The head of the humerus (upper arm bone) functions as the ball and the glenoid cavity of the scapula (shoulder blade) functions as the socket. But this shoulder socket is shallow, leaving the joint relatively unstable. The shoulder labrum is a cup-shaped rim of rubber-like fibrous cartilage that lines the socket to help secure the humerus and reinforce the joint.
Also known as the glenoid labrum, it provides support and stability to the shoulder joint in conjunction with the rotator cuff tendons and muscles. The labrum is also the attachment site for the tendon that connects to the long head of the biceps muscle and for several ligaments.
The long head of the biceps, which goes over the top of the shoulder ball (humerus) and mark in blue in the picture has the function of stabilising the shoulder joint in overhead activities like throwing.
If there is a tear in the upper part of the labrum where biceps tendon attaches, the shoulder malfunctions in overhead activities and games. This can cause pain and instability of the shoulder which can lead to a full fledged dislocation of the shoulder if the tear of the labrum extends anteriorly, or lead to tears in the rotator cuff muscles on either side of the biceps tendon (Supraspinatus and Subscapularis) due the repeated pressure between the muscles due to the malfunctioning biceps tendon.
The term SLAP stands for Superior Labrum Anterior and Posterior. In a SLAP injury, the top (superior) part of the labrum is injured. This top area is also where the biceps tendon attaches to the labrum. A SLAP tear occurs both in front (anterior) and back (posterior) of this attachment point. The biceps tendon can be involved in the injury, as well.
Injuries to the superior labrum can be caused by acute trauma or by repetitive shoulder motion. An acute SLAP injury may result from:
- A motor vehicle accident
- A fall onto an outstretched arm
- Forceful pulling on the arm, such as when trying to catch a heavy object
- Rapid or forceful movement of the arm when it is above the level of the shoulder
- Shoulder dislocation
People who participate in repetitive overhead sports, such as throwing athletes or weightlifters, can experience labrum tears as a result of repeated shoulder motion.
Many SLAP tears, however, are the result of a wearing down of the labrum that occurs slowly over time. In patients over 30 to 40 years of age, tearing or fraying of the superior labrum can be seen as a normal process of aging. This differs from an acute injury in a younger person
The common symptoms of a SLAP tear are similar to many other shoulder problems. They include:
- A sensation of locking, popping, catching, or grinding
- Pain with movement of the shoulder or with holding the shoulder in specific positions
- Pain with lifting objects, especially overhead
- Decrease in shoulder strength
- A feeling that the shoulder is going to “pop out of joint”
- Decreased range of motion
- Pitchers may notice a decrease in their throw velocity, or the feeling of having a “dead arm” after pitching
During the physical examination, your doctor will check the range of motion, strength, and stability of your shoulder.
He or she may perform specific tests by placing your arm in different positions to reproduce your symptoms. Your doctor may also examine your neck and head to make sure that your pain is not coming from a “pinched nerve.”
The results of these tests will help your doctor decide if additional testing or imaging of your shoulder is necessary.
O Brien’s test
X-rays. This imaging test provides clear pictures of dense structures, like bone. The labrum of the shoulder is made of soft tissue so it will not show up on an x-ray. However, your doctor may order x-rays to make sure there are no other problems in your shoulder, such as arthritis or fractures.
Magnetic resonance imaging (MRI) scans. This test can better show soft tissues like the labrum. To make a tear in the labrum show up more clearly on the MRI, a dye may be injected into your shoulder before the scan is taken.
The Imagine on the left is the MRI of a normal shoulder. The one on the right side depicts a SLAP tear, with the joint fluid seeping into the space between the labrum and the glenoid bone. The radiologist may sometimes suggest at Arthrogram so as to better delineate a doubtful SLAP tear.
In most cases, the initial treatment for a SLAP injury is nonsurgical.
Nonsteroidal anti-inflammatory medication. Drugs like ibuprofen and naproxen reduce pain and swelling.
Physical therapy. Specific exercises will restore movement and strengthen your shoulder. Flexibility and range-of-motion exercises will include stretching the shoulder capsule, which is the strong connective tissue that surrounds the joint. Exercises to strengthen the muscles that support your shoulder can relieve pain and prevent further injury. This exercise program can be continued anywhere from 3 to 6 months, and usually involves working with a qualified physical therapist.
Your doctor may recommend surgery if your pain does not improve with nonsurgical methods.
Arthroscopy. The surgical technique most commonly used for treating a SLAP injury is arthroscopy. During arthroscopy, your surgeon inserts a small camera, called an arthroscope, into your shoulder joint. The camera displays pictures on a video monitor, and your surgeon uses these images to guide miniature surgical instruments
There are several different types of SLAP tears. The surgeon will determine how best to treat your SLAP injury once it is seen fully during arthroscopic surgery. This may require simply removing the torn part of the labrum , or reattaching the torn part using sutures. Some SLAP injuries do not require repair with sutures; instead, the biceps tendon attachment is released to relieve painful symptoms (biceps tenotomy / biceps tenodesis).
Your surgeon will decide the best treatment option based upon the type of tear you have, as well as your age, activity level, and the presence of any other injuries seen during the surgery.
SLAP tear extending to posterior labrum
At first, your shoulder needs to be protected while the repaired structures heal. To keep your arm from moving, you will most likely use a sling for 2 to 6 weeks after surgery. How long you require a sling depends upon the severity of your injury and the complexity of your surgery.
Once the initial pain and swelling has settled down, your doctor will start you on a physical therapy program that is tailored specifically to you and your injury.
In general, a therapy program focuses first on flexibility. Gentle stretches will improve your range of motion and prevent stiffness in your shoulder. As healing progresses, exercises to strengthen the shoulder muscles and the rotator cuff will gradually be added to your program. This typically occurs 6 to 10 weeks after surgery.
Your doctor will discuss with you when it is safe to return to sports activity. In general, throwing athletes can return to early interval throwing 3 to 4 months after surgery.