The tendons of four muscles (infraspinatus, supraspinatus, subscapularis, and teres minor) in the upper arm form the rotator cuff, blending together to help stabilize the shoulder. Tendons attach muscles to bone and are the mechanisms that enable muscles to move bones. It is because of the rotator cuff tendons, which connect the long bone of the arm (the humerus) to the scapula (the shoulder blade) that we can raise and rotate our arms. The rotator cuff also keeps the humerus tightly in the socket (glenoid) when the arm is raised. The tough fibers of the rotator cuff bend as the shoulder changes position.
For normal shoulder function, each muscle must be healthy, securely attached, coordinated, and conditioned. When there are full or partial tears to the rotator cuff tendons, movement of the arm up or away from the body is impaired, making it difficult or impossible to rotate the arm in its ball-and-socket joint.
Shoulder pain is common among the many injuries that can happen in the shoulder joint. Patients with rotator cuff tears in particular, also complain of not being able to sleep on the affected side, and muscle weakness especially when attempting to lift the arm. A fully ruptured tendon may make it impossible to raise the arm or move it away from the body.
Rotator cuff tears do not usually occur in “healthy” shoulders. A history of shoulder problems raises the suspicion of possible rotator tear. Risk factors for tears include repetitive overhead activities, such as pitching a ball or painting a ceiling, excessive force with a fall, heavy lifting, and any degeneration or abrasion of the tendons.
Diagnosis of a rotator cuff tear is fairly easy to make on physical exam based on the patient’s active range of motion at the joint. A special test called an arthogram is often used to affirm a rotator cuff tear. For this test, dye is injected into the shoulder joint before X-rays are taken. If there is indication that dye has leaked out of the place where it was injected into the joint, there is likely to be a rotator cuff tear at that location. In addition, MRI and ultrasound can be used to visualize the rotator cuff tendons.
If a tear is determined to only be partial, conservative therapy will be initiated to control pain and promote healing. The treatment regimen known as R.I.C.E. can be very effective in some cases. Rest, ice, compression, and elevation are components of this treatment. It is important to rest the injury, as well as to initiate physical therapy as soon any acute pain has subsided. Anti-inflammatory medications such as non-steroid anti-inflammatory drugs (NSAIDs) are often prescribed for pain relief. If the recommendations of a physical therapist are followed on an ongoing and continuous basis, many partial tears will become very manageable with this treatment. If necessary, cortisone injections may be given if pain continues several weeks after conservative therapy is initiated. However, cortisone should not be used long term, as it may weaken the tendons.
If the tear extends through the complete thickness of the tendon there are several surgical options depending on the size, depth, and location of the tear. If other problems with the shoulder are discovered during the surgery, they will be corrected as well. Surgical options include:
Arthroscopy, in which miniature instruments are inserted into small incisions, can be used to remove bone spurs or inflammatory portions of muscle and to repair lesser tears.
A mini-open repair that combines arthroscopy and a small incision can be used to treat full-thickness tears.
In more severe cases, open surgery is required to repair the injured tendon. Sometimes a tissue transfer or a tendon graft is used. Joint replacement is also an option.
Recovering from shoulder surgery takes time, full recovery taking at least 6 months. Success of recovery is largely based on commitment to the exercise program your surgeon prescribes. Although each case is unique, shoulder surgery usually results in relief of pain and restoration of functional range of motion with compliance and hard work.