What is a shoulder SLAP tear?

This is a question that I receive from many of my patients. After all, having a shoulder SLAP tear sounds very strange. In reality, it is a tear of the shoulder labrum. As a physical therapist, I commonly treat shoulder labral tears and post-surgical repairs of the labrum. Patients tend to have difficulty conceptualizing a tear of the labrum compared to a muscle. That is where I come in. I help educate them on the shoulder joint and it’s many components. Read on if you are interested in learning about the shoulder labrum and SLAP tears. We will start with anatomy.

The shoulder joint

The main shoulder joint is called the glenohumeral joint. It is a large and complex joint that is made when the humerus (upper arm bone) and the scapula (shoulder blade) come together. It is a ball and socket joint. However the ball is much bigger than the socket. Think of a golf ball on a tee. The golf ball is the head of the upper arm bone and the tee is the outside part of the shoulder blade. This allows the shoulder to have the most movement of any joint in the body. However, it also has the least stability and this is what tends to get the shoulder joint in trouble.

“OpenStax AnatPhys fig.9.16 – Shoulder Joint – English labels 1” by OpenStax, license: CC BY. Source: book ‘Anatomy and Physiology’, https://openstax.org/details/books/anatomy-and-physiology.

The glenoid labrum

The area of the scapula that makes up the socket part of the shoulder joint is called the glenoid. A labrum attaches around the rim of the glenoid. It is called the glenoid labrum and is made up of fibrocartilage. It is very important in stabilizing the joint. It has a several functions, including:

Deepening and increasing the surface area of the glenoid.
Limiting forward and backward movement of the humeral head (ball) on the glenoid (socket).
Resisting shoulder dislocations and subluxations (partial dislocations).

“Sobotta 1909 fig.196 – socket of the shoulder joint – English Labels” by Johannes Sobotta is in the Public Domain.

The biceps

Interestingly enough, the biceps also plays a role in a shoulder SLAP tear. The biceps is a muscle located on the humerus (upper arm bone). It’s main function is to bend the elbow and rotate the forearm. The biceps has two muscle bellies. These muscle bellies are called the long head and the short head. Both of these come together and attach just below the elbow onto to the radius which is one the forearm muscles. The short head of the biceps attaches to a piece of bone that juts off of the shoulder blade called the coracoid process. The coracoid process is located just below the collarbone near the shoulder joint. The long head of the bicep travels through a groove near the top of the humerus and attaches inside the shoulder joint itself – at the top of the glenoid labrum.

So what is a SLAP tear?

SLAP is short for superior labral anterior posterior. It is the most common type of shoulder labral tear. Envision a clock face. It is a tear of the labrum from the 10 o’clock position to the 2 o’clock position. It can also involve the area where the long head of the biceps attaches. However the biceps attachment is not involved in every SLAP tear. SLAP tears can be traumatic or non-traumatic.

Traumatic – These typically occur after a single incident. This would be considered an acute injury.
Non-traumatic – These occur overtime from muscle weakness or hypermobility in the shoulder joint. This would be consider a chronic, degenerative injury.

How does a SLAP tear happen?

There are several different ways a person can tear their glenoid labrum. These are some of the most common:

Fall on an outstretched arm – This is one of the more common ways to acutely injury the labrum.
Repetitive throwing – This usually involves repetitive micro trauma. It causes a peel back of the labrum from the glenoid and typically involves a detachment of the biceps tendon.
Hyper extension – This is hypermobility of the joint which can lead to a degenerative tear of the labrum.
Heavy lifting – Lifting heavy items overhead such as in construction or factory work can lead to labral tears. Also performing movements where the force is far from the body such as swinging a hammer or a racquet can lead to a tear.
Direct trauma – A labral tear can occur with direct trauma to the shoulder joint.

What are the symptoms of a SLAP tear?

There are many symptoms of a SLAP tear. These include:

Acute or gradual onset of deep shoulder pain
Popping, locking, and catching with various movements
Pain with sudden shoulder movements – like reaching out to catch something
Pain with overhead movements
Loss of shoulder strength
Pain when lying on the affected shoulder
Feelings of shoulder instability – feels like the shoulder might pop out of place

There are also additional symptoms associated with the SLAP tears that involve the biceps tendon. These include:

Gradual onset of pain in the front of the shoulder
Pain that radiates from the shoulder down the front of the arm
Clicking and popping in the area of the biceps tendon
Pain at rest and at night

Who gets SLAP tears?

The highest incidence rate of SLAP tears are in the 20-29 year old and 40-49 year old age range. This typically includes athletes and manual laborers. SLAP tears are more common in men than in women. They also tend to occur with other shoulder injuries.

Are there risk factors for SLAP tears?

There are some risk factors for SLAP tears. These include

Participation in certain overhead sports
- Volleyball
- Baseball
- Swimming
- Track and field – javelin
Level of competition – higher level is more likely to have injury
Shoulder hypermobility/instability
Working in manual laborer occupations

Will I need surgery?

The answer is maybe. This depends upon the age, mechanism of injury, and activity level of the person. A young athlete or 40 year old manual laborer will probably choose to have surgery and return to their previous level of activity. However if your tear was more degenerative and you do not regularly do heavy lifting or overhead activities, then rehabbing with physical therapy will probably be all you need. Physical therapy can always be attempted first and then surgery would still be an option if PT proved to be unsuccessful in relieving symptoms.

Who should I see?

Physical therapist – A physical therapist is going to be an integral part of the healing process. Whether or not the person decides to have surgery, they will need physical therapy. Physical therapists can aid in decreasing pain and swelling, increasing strength and flexibility, and returning to sport or work safely. It is important to have a physical therapist assist in determining when the person is appropriate to return to sport or work and provide direction in how to prevent the injury from reoccurring.
Orthopedist – An orthopedist is also going to be needed. Imaging would be required to confirm the extent of the injury, especially, if other shoulder structures are involved. The orthopedist would discuss options including surgery.

What can I do?

Relative rest – Resting the area to decrease further pain and damage from occurring is one of the best ways to decrease pain. Basically, stay away from the activities that are causing pain. This gives the area time to rest and heal. If you keep doing what is causing the injury, it is not going to get better. This might include not participating in your sport or going on light duty for a period of time. If you are not able to participate in your normal activity, then you can supplement with non-irritating activities such as biking, walking, or jogging while your shoulder is healing.
Ice – Ice can help decrease pain and swelling in the tendon. Ice the painful area for 15 to 20 minutes at a time. I would recommend using an ice pack several times per day if the pain is constant or is preventing you from participating in an activity. Ice immediately after activity.
Shoulder range of motion – It is important to be able to maintain full range of motion of the shoulder whether or not you plan to have surgery. Below is a video showing simple shoulder range of motion exercises that can be daily. Having a pulley is very helpful in performing these exercises.
- Shoulder mobility exercises
Posture – Having forward, rounded shoulders causes muscular imbalances in the shoulder. It stretches out the rotator cuff and scapular stabilizing muscles which are important for shoulder stabilization. It also shortens the pectoralis major, pectoralis minor, and the biceps and causes them to get tight. Below is a video showing how to use a stretch the pecs and biceps and also how to use a wall to check your posture.
- Doorway pec stretch, bicep stretch, posture at wall
Soft tissue mobilization – Soft tissue mobilization helps release the muscles around the shoulder and decrease inflammation in the shoulder. Use a massage ball or lacrosse ball to roll on the painful areas all around the shoulder. Spend a good 3 to 5 minutes rolling. Do not roll so hard that you bruise the area, but it should be a pretty painful sensation. Roll out the area no more than a few times a week. See the video below.
- Shoulder soft tissue mobilization

Strengthen the rotator cuff and scapular stabilizers– These are the stabilizing muscles of the shoulder that allow the shoulder to reach and lift without injury or irritation. Using loop resistance bands and resistance bands can increase strength and difficulty.

In review

The main shoulder joint is called the glenohumeral joint.
- It is a large and complex joint that is made when the humerus (upper arm bone) and the scapula (shoulder blade) come together.
The area of the scapula that makes up the socket part of the shoulder joint is called the glenoid.
A labrum attaches around the rim of the glenoid.
- It plays an important role in stabilizing the joint.
A SLAP tear is a tear of the labrum from the 10 o’clock position to the 2 o’clock position.
- It can also involves the area where the long head of the biceps attaches.
It can be traumatic or non-traumatic.
Symptoms include deep shoulder pain and popping/catching.
Risk factors include certain sports, hypermobility in the shoulder, and manual laborer occupations.
Surgery might be needed.
You would need to see an orthopedist for imaging and surgical options.
A physical therapist will also be essential whether or not surgery is needed.
There also things that you can do
- Relative rest
- Ice
- Shoulder range of motion
- Posture
- Soft tissue mobilization
- Strengthening of rotator cuff and scapular stabilizers