The shoulder is the most mobile joint in the human body. The joint includes four tendons. The purpose of a tendon is to hold muscle to bone. Together, these four "rotator cuff" tendons stabilize the upper arm bone to the shoulder socket and allow a wide range of motion in the shoulder.

Any swelling, inflammation, tearing, or bony changes around these tendons causes pain when a person tries to move the arm above the head, behind the back, or straight out in front.

The tendons pass underneath a rigid bony arch in the shoulder. The most common cause of shoulder pain is when the tendons become trapped under this arch. The compressed tendons become inflamed or damaged, a condition called rotator cuff tendinitis. This can occur from general wear and tear as you get older, an activity that requires constant shoulder use like baseball pitching, or an injury.

Shoulder pain can also be due to:

• Arthritis in the joints about the shoulder (gradual narrowing of the joints and loss of protective cartilage).
• Bursitis (inflammation of a fluid-filled sac, or bursa, that lies between tendon and skin or between tendon and bone). Normally a bursa protects the joint and helps make movement more fluid.
• Fractures of the shoulder bones.
• Frozen shoulder syndrome occurs when you don't move your shoulder because of pain or injury. The muscles or connective structures stiffen up inside the shoulder and make any motion painful and difficult.
• Inflammation of nearby tendons, such as those connected to the bicep muscles of your arms, from overuse or injury.
• Dislocation of your shoulder, which is when the ball-shaped head of your arm comes out of the socket.

When you first feel shoulder pain, apply ice for up to 15 minutes, then leave it off for 15 minutes. Repeat this cycle for several hours. Wrap the ice in a cloth, DO NOT apply ice directly to the skin. Then, continue to ice 3 to 4 times a day for 2 to 3 days.

Rest the shoulder from strenuous activity for the next few days. When the pain and swelling have subsided, gradually begin to strengthen the shoulder muscles. Perform light weight lifting, using a full range of motion. Consider seeing a physical therapist for help doing this safely.

Ibuprofen or acetaminophen (Tylenol) may help reduce inflammation and pain.

Call 911 if you feel sudden pressure or crushing pain in your shoulder, especially if it extends from your chest, jaw, or neck, or occurs with shortness of breath, dizziness or sweating. Very sudden shoulder pain can, occasionally, be a sign of a heart attack.

If you just had a severe blow or injury and your painful shoulder is swollen, badly bruised, or bleeding, get safely to an emergency room where they will check for a fracture or dislocation.

Contact your doctor if :

• You have fever, swelling, or redness.
• You are unable to use the joint.
• Your pain lasts more than 1-2 weeks despite self-care measures.

Your health care provider will perform a physical examination, including a detailed examination of the shoulder, and ask questions such as.

• Does the pain affect one or both shoulders?
• Does your pain travel from the shoulder to other joints?
• Where in your shoulder do you feel the pain? The front, side, or top?
• Does the pain occur when you lift your arm overhead or away from your body?
• Did your pain start suddenly? Is it severe? Or, did it begin slowly and mildly and then get worse?

Diagnostic tests that may be performed vary depending on the results of your physical examination. Treatment may include the following:

• Nonsteroidal anti-inflammatory drugs (NSAIDs)
• A corticosteroid injection
• Referral to a physical therapist and instructions on rehabilitation

Surgery is a last resort.

• If you have had shoulder pain in the past, use ice and ibuprofen after exercising.
• Learn proper exercises to stretch and strengthen your rotator cuff tendons and shoulder muscles. A doctor or physical therapist can help.
• If you are recovering from tendinitis, continue to perform range-of-motion exercises to avoid "frozen shoulder."
• In sports-related activities, learn proper technique to prevent painful and expensive shoulder problems.

Braman JP, Tehrany AM, Flatow EL. Rotator cuff repair. Am J Orthop. 2005; 34(6): 267-270.

Paternostro-Sluga T, Zoch C. Conservative treatment and rehabilitation of shoulder problems. Radiologe. 2004; 44(6): 597-603.