The shoulder is the most mobile joint in the human body, allowing use of the upper extremities. However, because of this mobility, the shoulder is also predisposed to develop instability and injury.
Whether you are throwing a ball or lifting a box, this rubbery tissue between the glenoid (the socket part of the shoulder joint) and the humerus (upper arm bone) helps stabilize the ball of your shoulder joint to keep it in place.
If the labrum tears, which can result from an injury or the aging process, there will not be enough tissue to act as cushioning between the bones and to stabilize the shoulder joint.
Understanding what a labral tear is and the types of treatments a shoulder specialist offers can help you be on your way to performing everyday tasks without worrying about shoulder pain.
What Is a Shoulder Labrum?
The labrum is a cup-shaped rim of cartilage that lines and reinforces the ball-and-socket joint of the shoulder. The shoulder joint is composed of the glenoid (the shallow shoulder “socket”) and the head of the upper arm bone known as the humerus (the “ball”). These two bones are connected by ligaments — tough tissues forming tethers that hold the bones in relationship to each other.
There are two kinds of cartilage in the joint. The first type is the white cartilage on the ends of the bones (articular cartilage) which allows the bones to glide on each other. When this type of cartilage starts to wear out (a process called arthritis), the joint becomes painful and stiff. The labrum is a second kind of cartilage in the shoulder, which is different from the articular cartilage. This cartilage is more fibrous or rigid than the cartilage on the ends of the ball and socket. Also, this cartilage is also found only around the socket where it is attached.
Function of the Labrum
The labrum has two functions. The first is to deepen the socket so that the ball stays in place. The labrum goes all the way around the socket and in most areas is firmly attached to the bone of the socket. In some areas it is not firmly attached.
The second function of the labrum is as an attachment of other structures or tissues around the joint. The ligaments that help hold the joint together attach to the labrum in certain key locations. If there is an injury to the shoulder that tears the ligaments, sometimes the labrum is pulled off of the rim of the bone as well.
What is a Labrum Tear?
A shoulder labral tear is also called a shoulder joint tear or a glenoid labrum tear. It occurs when the ring of cartilage surrounding the outer portion of the shoulder socket—or labrum—tears as the result of high stress or overuse. These tears are common among athletes and those who use the shoulder for repetitive activities, such as weightlifting or throwing.
Types of Shoulder Labrum Tears
There are several types of torn shoulder labrum, including:
- Bankart Lesions or Tears
These tears are common in younger people who dislocate their shoulder. This type of torn labrum occurs in the lower portion of the glenoid socket. A person who has sustained a Bankart tear may feel as though their shoulder could fall out of place if they move their arm in a certain way.
- Superior Labrum, Anterior to Posterior (SLAP) tears or lesions
SLAP tears go from the front to the back of the cartilage in the middle of the glenoid. Among athletes, this tear is more likely to occur in those who play tennis, baseball, or softball, as these sports involve quick snapping arm movements over the top of the shoulder.
- Posterior Shoulder Instability
These types of tears occur in the back of the glenoid socket. They can occur due to a severe injury or if a shoulder dislocates posteriorly.
Labral tears to the shoulder damage the ring of cartilage surrounding the shoulder socket.
Common causes of labral tears in the shoulder include:
- Trauma, such as a fracture or dislocated shoulder
- Repetitive motion
Sports-Related Risk Factors
While this condition commonly occurs as a result of other shoulder injuries, like dislocations, rotator cuff injuries, and torn bicep tendons, some specific causes of sports-related labral tears include:
- A fall on an outstretched arm
- A direct hit to the shoulder
- A violent blow while reaching overhead
- A sudden tug on the arm
The most common symptoms of a torn shoulder labrum are:
- Shoulder pain
- Sense of instability in the shoulder
- Feeling of grinding, locking or catching while moving the shoulder
- Decreased range of motion
- Loss of strength
- Pain at night or while performing daily activities
Because this cartilage is deep in the shoulder, it is very difficult to make the diagnosis of a torn labrum upon physical examination. There are several tests that the physician can perform that may indicate a torn labrum, but these tests are not always accurate.
The best tests available to make the diagnosis of a labral tear are magnetic resonance imaging (MRI) scans or a test called a CT-arthrogram (the latter is a CAT scan preceded by an arthrogram where dye is injected into the shoulder). Both of these tests are relatively good at defining a labrum tear due to a subluxation or dislocation, but they are only around 80 percent to 85 percent accurate. If the MRI definitely shows a tear then frequently it will be present. The problem is that the MRI may miss smaller tears and cannot reliably make the diagnosis in larger tears of the labrum.
The most accurate way to make the diagnosis of labrum tearing is with arthroscopy of the shoulder. Unfortunately this is an operative procedure and requires some form of anesthesia.
The treatment depends upon which kind of tear there is in the labrum. Tears that are due to instability of the shoulder, either subluxation or dislocations, require that the labrum be reattached to the rim of the socket. This can be done with an incision on the front of the shoulder, or it can be done with arthroscopic techniques through smaller incisions.
Conservative care to eliminate pain and restore motion is the first step in labral tear treatment. Anti-inflammatory medications and rest are typically recommended. Depending on the size and location of the tear, strengthening is often successful. Alternative treatments including glucosamine, hyaluronic acid, and non-steroidal anti-inflammatory medications (NSAIDs) are also considered.
When conservative treatment fails, surgical repair can be performed. Doctors often repair labral tears with arthroscopy. This minimally invasive procedure involves making a small incision in your shoulder to allow a small camera to capture images of the joint. Your surgeon will then to trim, repair, or reattach your labrum as needed.
Expect to be in a sling for a month or so after surgery. Once the swelling has subsided, you may begin moving your shoulder again with help from a physical therapist. Keep in mind that it could take up to two months for your labrum to heal completely and an additional two months to build up the same strength you had before the injury.
Recovery From Labrum Surgery
The actual recovery depends upon many factors, such as where the tear was located, how severe it was and how good the surgical repair was. It is believed that it takes at least four to six weeks for the labrum to reattach itself to the rim of the bone, and probably another four to six weeks to strengthen. Once the labrum has healed to the rim of the bone, the stress will diminish and strength will increase. It is important not to reinjure it while it is healing.
The amount of motion and strengthening of the arm that will be allowed after surgery depends upon many factors, and it is up to the surgeon to let you know your limitations and how fast to progress.
Ask Your Doctor
To learn more about shoulder labral tears, including your options for prevention and treatment, speaking with an orthopedic specialist is your best choice. Our skilled and experienced orthopedic surgeons will perform a thorough examination of your shoulder, analyze X-rays, and conduct physical tests.
To learn more about the procedure or to schedule an appointment with one of our rotator cuff repair specialists, call us at 800-698-1280.