A superior labral anterior-posterior (SLAP) lesion is an injury to the part of the shoulder called the labrum. The labrum is the cuff of cartilage that extends the socket part of the shoulder blade to better accept the ball end of the arm bone.
A SLAP lesion is a tear that occurs where the tendon of the biceps muscle meets the labrum.
SLAP lesions are usually classified into one of four types:
- A Type I tear is a fraying of the labrum.
- A Type II tear is when the biceps tendon and labrum become detached from their bed on the socket joint.
- A Type III tear is when the labrum has a flap of tissue hanging down into the joint.
- A Type IV tear is when the labrum has a tear that extends into the biceps tendon.
What causes a SLAP lesion?
Injuries to the labrum are tears that can be caused by trauma or repetitive shoulder motion.
- A fall onto an outstretched arm or the shoulder.
- A sudden pull to the shoulder, such as when tying to lift a heavy object.
- A sudden upward motion, such as when pitching a ball or trying to stop a fall or slide.
- A direct blow to the shoulder.
Repetitive shoulder motion injuries are often associated with sports injuries that occur from activities such as pitching a baseball, throwing a football or lifting weights.
What are the symptoms of a SLAP lesion?
There are several symptoms that might indicate a SLAP lesion injury. These include:
- A catching sensation, clicking or locking in the shoulder.
- Pain in the front or top of the shoulder.
- Increased pain with movement, especially with overhead activities.
- Decreased range of motion of the shoulder and arm.
- Susceptibility to dislocation.
Determining if pain is caused by a SLAP lesion is sometimes difficult because the injury often does not show up well on normal MRI scans. However a MRI scan with dye placed into the shoulder is often helpful to diagnose a labral tear. Sometimes, though, an actual diagnosis is made at the time of surgery when the orthopaedic surgeon has an opportunity to look inside the shoulder, most often during an arthroscopic surgical procedure.
How is a SLAP lesion treated?
Once a diagnosis has been made, an orthopaedic surgeon recommends the best treatment option. There are both surgical and non-surgical options, although surgery is most often needed.
Some tears can be treated conservatively. Non-surgical treatment may include the following:
- Avoidance of activities that worsen pain (overhead activity, heavy lifting, repetitive motions).
- Anti-inflammatory medication.
- Physical therapy to regain motion and strength.
Surgical diagnosis and repair of SLAP lesions is usually done with shoulder arthroscopy. Arthroscopic repair makes use of a fiberoptic scope connected to a video camera and small, specialized instruments. In this surgery, the scope and instruments are inserted into small puncture-type incisions rather than through a larger open incision.
The type of surgical repair depends upon the extent of damage found. Some possible fixes include the following:
- Type I injury: The surgeon uses a shaver to remove, or debride, the fraying of the tissue or to prevent a small tear from worsening.
- Type II injury: The loose part of the labrum and bicep is "tacked" down to the cup of the joint.
- Type III injury: The flap of labrum tissue hanging down into the joint is either repaired or removed, depending upon the size of the flap.
- Type IV injury: The labral tear will be removed and the biceps tendon repaired. The labrum and/or biceps tendon may also need to be reattached to the cup of the joint.
After surgery, the start of physical therapy rehabilitation is dependent upon the type of surgical repair. Rehabilitation of the shoulder may begin immediately for a debridement or may be delayed up to a month after a repair while the labrum or biceps heal.