The shoulder is a ball and socket joint made up of 3 bones: the humerus, which is the bone in your upper arm, the scapula, or shoulder blade, and clavicle, which is your collar bone. The head of the humerus at the top of the bone is the ball. It sits in a rounded socket in your scapula called the glenoid. The head of the humerus is much bigger than the glenoid, like a golf ball sitting on a golf tee. However, the glenoid has a strong fibrous ring surrounding it to help deepen the socket by 50% in order to stabilize the head of the humerus in the shoulder joint and prevent the ball from falling off the tee.
This ring is called the glenoid labrum and serves as the attachment site for both muscles and ligaments that work at the shoulder joint. A labral tear occurs when this ring is disrupted, frayed, or torn completely. When this occurs, the shoulder joint becomes unstable and is prone to further injury. The most common injury to the glenoid labrum is a SLAP tear: superior labrum anterior to posterior. Meaning in this injury, the superior or top portion of the labrum is injured. This is where the biceps tendon attaches to the labrum and the tear occurs both in front of (anterior) and behind (posterior) the biceps attachment site.
There are 4 classifications of these lesions. Type 1: the labrum has degenerative changes over time and fraying at the edges but remains firmly attached to the glenoid rim. Type 2: the superior rim is detached completely from the anterior to posterior glenoid rim and is lifted up by the biceps tendon. This creates an unstable biceps tendon attachment. Type 3: part of the superior labrum is displaced into the joint. Imagine how a bucket handle drops to the side of a bucket when released. This is how the labrum appears, however part of the labrum is still attached to the glenoid rim with the biceps tendon intact. Type 4: a greater percentage of the superior labrum is involved in the bucket handle tear, including a splitting of the biceps tendon.
Causes
SLAP tears can commonly be caused by either acute trauma or repetitive motions of the shoulder joint. A few examples of trauma include a motor vehicle accident, a fall onto an outstretched arm, shoulder dislocation, forceful pulling on the arm like when trying to catch a heavy object, or forceful movement of the arm in overhead activities. Athletes who participate in repetitive overhead sports, such as throwing athletes or weightlifters, are also at a higher risk of labral tears due to the repeated and forceful shoulder motion.
It is important to note that in older individuals SLAP tears may result from wearing down of the labrum that occurs slowly over time. Tearing or fraying of this labrum may be seen as part of the normal aging process and is different from an acute injury that may occur in a younger population.
Symptoms
Individuals with a SLAP tear may report popping, catching, or clunking with shoulder movement because the torn or frayed labrum has loose ends that get caught in the shoulder joint as the arm moves through its range of motion. These pieces may even get trapped in the joint. Another common symptom is pain with lifting objects, especially overhead, and maintaining a specific position. There may be a decrease in shoulder strength and range of motion or a feeling that the shoulder is going to pop out of the joint. Baseball pitchers specifically may notice a decrease in their throwing velocity.
However, not all labral tears produce the symptoms listed above. When tears are small and if proper care is taken not to stress the injury further, there may not be any pain at all. A tear may pop or click without being painful but due to the lack of blood supply available at the labrum it is likely that a tear can progress and lead to pain and weakness without proper treatment.
Can physical therapy help?
When labral tears cause minor symptoms without greatly affecting the stability of the shoulder joint, physical therapy can be helpful in decreasing those symptoms and returning the shoulder to its prior level of function. The first step in PT is patient education. It is very important to advise patients with SLAP tears to avoid putting excessive stress on the biceps muscle, as the tendon attaches directly on the superior labrum and can further damage that tear if not rested. For example, overhead movements and particularly bicep curls should be avoided until the labrum is more stable.
Manual therapy is utilized to improve pain free range of motion and decrease the tension that can build up in surrounding muscles. With a shoulder injury, it is common for people to start to use muscles improperly to compensate for the pain. For example, instead of just lifting the arm straight up over their head, they may lift their whole shoulder, engaging neck and back muscles, and use momentum to achieve that movement. Over time, these movement patterns start to negatively affect those surrounding muscles, which is where manual therapy comes in. Techniques such as deep tissue massage and myofascial release use pressure to help ease the tension that can build up and contribute to shoulder pain.
Physical therapy will also focus on shoulder strengthening. Improving the strength of the muscles surrounding the shoulder will help decrease the stress placed on the labrum and allow for better healing. Exercises in internal and external rotation are the initial focus as they target muscles of the rotator cuff without putting excessive forces on the labrum. A stretching program is also important because a decrease in flexibility of the shoulder can lead to poor posture habits. Stretching can help restore a normal balance between the muscles surrounding the joint to help them work better together.
Is surgery necessary?
If physical therapy is unsuccessful in reducing the symptoms of a SLAP tear, or if an individual presents with excessive instability at the shoulder joint, surgery may be appropriate to stabilize the joint. The type of surgery recommended depends on the type of tear. A type 1 tear is typically regarded as benign and surgery is not necessary. For a type 2 tear an arthroscopic repair is recommended to reattach the labrum to the glenoid. A type 3 tear may require an excision or repair of the displaced labrum depending on how much of the labrum has torn away and a type 4 tear will also require a repair of the biceps tendon. Following surgery physical therapy is highly recommended in restoring shoulder strength and range of motion. The PT protocol is typically up to the surgeon. For more information on physical therapy visit www.totalperformancept.com.
For further information on labral tears, contact Total Performance Physical Therapy to schedule an appointment.
