What most people call the shoulder is really several joints that combine with tendons and muscles to allow a wide range of motion to the arm, from scratching your back to throwing the perfect pitch. Mobility has its price, however. It may lead to increasing problems with instability or impingement of soft tissue resulting in pain. You may feel pain only when the shoulder is moved, or all of the time. The pain may be temporary and disappear in a short time, or it may continue and require medical diagnosis and treatment.
What causes shoulder pain?
Most shoulder problems involve the soft tissues, muscles, ligaments and tendons, rather than bones. And most of these problems fall into three major categories:
Other much more rare causes of shoulder pain are tumors, infection and nerve-related problems.
Tendinitis
A tendon is a cord that connects muscle to bone or other tissue. Most tendinitis is a result of the wearing process that takes place over a period of years. Generally, tendinitis is one of several types:
Sometimes, excessive use of the shoulder leads to inflammation and swelling of a bursa, a condition known as bursitis. Bursas are fluid-filled sacs located around the joints which lessen the friction caused by movement of the shoulder. Bursitis often occurs in association with rotator cuff tendinitis. Sometimes the many tissues in the shoulder become inflamed and painful, limiting the use of the shoulder. The joint may stiffen as a result, a condition called a "frozen shoulder." Fortunately, with appropriate care, this condition will resolve itself.
Injury/Instability
Sometimes the bones in one of the shoulder joints move (or, in an injury, are forced) out of their normal position. This instability can lead to dislocation of one of the joints in the shoulder. Recurring dislocations, which may be partial or complete, cause pain and unsteadiness when you raise your arm or move it away from your body. When you lift your arm over your head, the shoulder may feel as if it is slipping out of place or be uncomfortable with the unusual feeling that some people refer to as having a "dead" arm.
Arthritis
Shoulder pain can also result from arthritis. There are many types of arthritis, but generally it involves wear and tear changes with inflammation of the joint, causing swelling, pain and stiffness. Arthritis may be related to sports or work injuries.
Often people will avoid shoulder movements in an attempt to lessen the pain arising from these conditions. This sometimes leads to a tightening or stiffening of the soft tissue parts of the joint, resulting in a painful restriction of motion.
Treatment
Treatment generally involves altering activities, rest and physical therapy to help you improve shoulder strength and flexibility. Medication may be prescribed to reduce inflammation and reduce pain, but it should be taken only as directed. Injections of drugs may also be used to treat pain.
Ninety percent of patients with shoulder pain will respond to simple treatment methods such as altering activities, rest, exercise and medication. However, certain types of shoulder problems, such as recurring dislocation and some rotator cuff tears, may require surgery.
Common sense solutions such as avoiding overexertion or overdoing activities in which you normally don't participate can help to prevent shoulder pain.
When should you seek medical care?
Many patients ignore temporary minimal shoulder symptoms with few bad effects. In the case of an acute injury, if the pain is intense, you should seek medical care as soon as possible. If the pain is less severe, it may be safe to wait a few days. If symptoms persist, an orthopaedist, who is specifically trained in the workings of the musculoskeletal system, including the diagnosis, treatment and prevention of problems involving muscles, bones, joints, ligaments and tendons, should be consulted.
Diagnosis
Determining the source of a shoulder problem is a vital step in recommending the right method of treatment. First, your orthopaedist will ask how and when the pain started, whether it has occurred before and how it was treated, and inquire about your general health. Because many shoulder problems are aggravated by specific activities, and relieved by specific activities, a medical history can be a valuable tool in finding the source of and treating your pain.
Next, your orthopaedist will perform a physical examination, which may include looking for physical abnormalities, swelling, deformity or muscle weakness, or feeling for tender areas, and observing the range of shoulder motion, how far and in which direction you can move your arm.
X-ray studies may be required so your orthopaedist can look closely at the bones and joints in your shoulder. Other diagnostic techniques that may be used include CT scan (computerized tomography), which provides a more detailed view of the shoulder area; electrical studies such as the EMG (electromyogram), which can indicate nerve damage; or an arthrogram, an X-ray study in which dye is injected into the shoulder to allow the orthopaedist to better see the joint and its surrounding muscles and tendons. MRI (magnetic resonance imaging) and ultrasound are other valuable diagnostic tools because they provide images of the soft tissues without using radiation. Arthroscopy is a surgical procedure in which the orthopaedist looks inside the joint with a lighted telescope. It may indicate soft tissue injuries that are not apparent in the physical examination, X-rays and other tests.
This information has been prepared by the American Academy of Orthopaedic Surgeons and is intended to contain information on the subject from recognized authorities. However, it does not represent official policy of the Academy and its text should not be construed as excluding other acceptable viewpoints.