Shoulder pain is discomfort that affects any part of the shoulder joint or the area around it. Trauma, degenerative disease, underuse, overuse or aging can all damage the cartilage or bone within the joint or the muscles, tendons and ligaments supporting the shoulder. Even conditions such as liver disease or TMJ disorder can result in shoulder pain.  

Each year, about 4 million Americans seek medical care for pain related to shoulder sprains, strains, dislocations, fractures or other problems, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

Shoulder pain can be diagnosed through a medical history, a physical examination and imaging tests such as standard x-rays, MRI or an arthrography (x-ray procedure in which contrast fluid is injected into the joint to outline structures).

In many cases, home–based treatments, such as icing, over-the-counter medications or stretching exercises, can successfully treat conditions that cause minor shoulder pain. However, more significant pain, especially if it does not go away within one to two weeks, may require professional medical attention. 

Treatment for shoulder pain varies according to the type and severity of the injury. In some cases, the shoulder may be immobilized, whereas in other cases the patient may be instructed to perform certain exercises. Medications often help.  Physical therapy or occupational therapy may be necessary to reduce the pain and restore function. Arthroscopy, arthroplasty or other surgery may be recommended if noninvasive treatments fail.

Sometimes shoulder pain cannot be prevented. However, people can often reduce their risk with measures such as stretching and practicing good posture and ergonomics.

Shoulder pain is the result of an injury, degenerative disease, or wear and tear from overuse or aging that damages the soft tissues – including muscles, tendons and ligaments – or bones of the shoulder joint or the area around it. These tissues must remain healthy and strong if they are to keep the shoulder joint anchored, stabilized and working properly. If these tissues become damaged, shoulder pain can result. 

Each year, around 4 million people in the United States seek medical care for pain related to shoulder sprains, strains, dislocations or other problems, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. In addition, orthopaedic surgeons – physicians who treat disorders of the bones, muscles and related structures – receive 1.5 million annual visits related to conditions affecting the shoulder.

The shoulder is the most movable joint in the body. It includes four bones – the humerus (arm bone), the clavicle (collarbone), the scapula (shoulder blade) and the sternum (breastbone). The primary shoulder joint, technically known as the glenohumeral joint, it is a modified ball and socket in which a “ball” in the upper humerus fits against a shallow, disc-shaped socket (glenoid fossa) in the scapula. A soft-tissue envelope known as a capsule encircles the glenohumeral joint and is lined by a thin, smooth synovial membrane.

Additional joints in both shoulders include:

• Acromioclavicular (AC) joint. Several ligaments and a cartilaginous disc connect the acromion (the highest point of the shoulder at the top of the scapula) and the clavicle. The AC joint is often injured in collision sports such as football and bicycling.
  
  
• Sternoclavicular joint. Several strong ligaments connect the clavicle to the sternum near the body’s midline. This synovial joint is the most stable and least injured of the shoulder joints.  

Muscles, tendons (including four rotator cuff tendons) and ligaments keep the bones of the shoulder in place. Ligaments attach the shoulder bones to each other, and the tendons attach the bones to the shoulder muscles. These soft tissues help the muscles move the shoulder.

Other important structures of the shoulder include the rotator cuff, which is a combination of tendons and muscles that holds the “ball” of the humerus against the shallow socket of the glenohumeral joint. This helps provide great mobility and strength to the shoulder joint.

In addition, two filmy, sac-like structures called bursae help bone, muscle and tendon to work together smoothly while minimizing friction. The bursae protect the rotator cuff form the bony arch of the acromion.

The shoulder’s anatomy allows a wide range of motion. However, this flexibility also makes the joint unstable and prone to injury.

Shoulder pain can stem from many causes. In some cases, shoulder pain is localized, meaning that it is confined to a specific area. In other cases, pain may be more widespread, affecting areas throughout the shoulder and even into the neck, back or arm.

Shoulder pain varies depending on the nature of the injury, degenerative process or abuse that is the source of the pain. Common causes of shoulder pain include:

• Dislocation. Shoulder injuries of this type are the most common major dislocations in the body. In most cases, a dislocation occurs when some force (such as a fall or sports injury) pulls the shoulder outward or an extreme rotation of the shoulder pulls the ball of the humerus (long bone of the arm extending from the shoulder to the elbow) out of the shallow socket. Dislocation often occurs when a backward pull on the arm overwhelms the muscles.

A partial dislocation in which part of the ball remains against the socket is known as a subluxation. A few patients may experience minor subluxation followed by reduction itself. Subluxation, sometimes painful, can also result from neurovascular conditions such as stroke.

Shoulders can dislocate in several directions – forward, backward or downward. Dislocation usually causes pain that may be intensified when accompanied by muscle spasms. Swelling, numbness, weakness and bruising are common, as are associated ligament (tough, fibrous tissue connecting bones or cartilage at a joint or supporting an organ) or tendon (tough, inelastic fibrous tissue that connects muscle with its bony attachment) damage and – less frequently – nerve damage.

• Separation. Occurs in the area where the collarbone (clavicle) and the shoulder blade (scapula) meet. Ligaments that hold the joint together may become partially or completely torn, causing the outer end of the clavicle to slip so that it does not properly join with the scapula. Blows to the shoulder or falling with an outstretched hand are the most common causes of shoulder separations.
  
  People who suffer a shoulder separation experience pain and tenderness, usually over the acromioclavicular (AC) joint between the acromion and the clavicle especially when the shoulder is moved. In some cases, a bump may form in the middle of the shoulder over the acromioclavicular joint. The AC joint can be palpated by moving fingers over the collarbone from medial (near the center of the body) to lateral (away from the center of the body). 
  
  
• Torn rotator cuff. The rotator cuff is made up of the muscles and tendons that connect the humerus to the shoulder blade. Tendons in the rotator cuff are normally strong, but they can become inflamed and tear as a result of overuse, wear and tear associated with aging or an accident such as a collision. Sports that require repeated overhead motion (e.g., pitching in baseball) and occupations that require heavy lifting are primary sources of rotator cuff tears. Usually patients may have difficulty raising their arm above the shoulder (90 degrees). Small tears may go unnoticed.
  
  
• Tendinitis, bursitis and impingement syndrome. These three closely related conditions can occur separately or in combination. They are sometimes grouped under the heading of an injured rotator cuff. The three conditions are:
  
  
• • Tendinitis. Inflammation of a tendon. In the shoulder, tendinitis is most likely to affect the tendons of the rotator cuff or biceps as a result of pinching from surrounding structures.
    
    
  • Impingement syndrome. When tendinitis affects the rotator cuff, the inflamed and thickened tendon may become trapped under the acromion. This squeezing of the rotator cuff is called impingement syndrome.
    
    
  • Bursitis. Inflammation of the bursae. These sacs protect the shoulder and help make movement more fluid. However, they can become inflamed either separately or in tandem with tendinitis and impingement syndrome.
    
    
  Repetitive motions involving the arms, or wear and tear over many years can irritate or wear down tendons, muscles and surrounding tissues. Sports involving overuse of the shoulder and jobs that require excessive overhead reaching are sources of these disorders. In addition, they may be caused by diseases such as rheumatoid arthritis.
  
  Tendinitis, bursitis and impingement syndrome may cause a slow onset of discomfort or pain in the upper shoulder. The pain also may travel to down the arm to the elbow and forearm. Some patients report difficulty sleeping on the shoulder. In addition, tendinitis and bursitis often cause pain when the arm is lifted away from the body or overhead. Strong pain may be felt if the arm or shoulder is pushed forcefully up, forward or backward. Patients with these conditions often have limited shoulder mobility.
  
  
• Fracture. A partial or total crack through a bone, frequently as the result of a fall or blow to the shoulder. Fractures often involve the clavicle or the neck of the humerus, which is the area just below the ball. Although a fracture may not be a major injury, it usually results in severe pain accompanied by redness and bruising.

• Arthritis of the shoulder. A degenerative disease caused by either wear and tear of the cartilage (osteoarthritis) or inflammation of one or more joints (rheumatoid arthritis). Ankylosing spondylitis, a form of arthritis that primarily affects the spine, can also cause shoulder pain. Arthritis also can affect supporting structures, including muscles, tendons and ligaments. People with arthritis of the shoulder experience pain – typically over the AC joint - and decreased shoulder mobility.
  
  
• Osteophytes (bone spurs). These are often caused by degenerative changes such as osteoarthritis. Bony projections can restrict the shoulder’s range of motion and cause pain.
  
  
• Frozen shoulder. Also known as adhesive capsulitis, this condition causes pain that severely restricts the patient’s ability to move the shoulder. Patients may be unable to raise their arm without feeling significant pain, and stiffness and pain may worsen at night. Injuries are a common source of frozen shoulder, but it also can result from rheumatic diseases and shoulder surgery. Hallmarks of this condition include inflammation, abnormal bands of tissue between the joint surfaces and a lack of synovial fluid (which normally provides lubrication to the gap between the humerus and its socket). People with diabetes, stroke, lung disease, rheumatoid arthritis and heart disease are at greater risk for frozen shoulder.
  
  
• TMJ disorder. This condition primarily affects the temporomandibular joints of the jaw but can cause pain in the shoulders, ears, neck, back and elsewhere..
  
  
• Pinched nerve. Nerves can be compressed throughout the body. Examples that affect the shoulder include impingement of the axillary nerve in the armpit, which can result from use of crutches, and subscapular nerve entrapment, an uncommon condition caused by restriction of the subscapular nerve. A herniated disc in the neck can cause pain running down the shoulder and arm.
  
  
• Heavy packs. Hefty or poorly positioned backpacks used by schoolchildren and oversized purses, briefcases or luggage used by adults can injure the shoulders and back.
  
  
• Thoracic outlet syndrome (TOS). A name given to several unrelated disorders, some of them controversial and ill-defined, that affect blood vessels and nerves in the region between the base of the neck and the armpit. Symptoms can include shoulder, neck and arm pain and weakness. True neurologic TOS, caused by atypical anatomic features that are present at birth, is rare and can be treated surgically, according to the National Institutes of Health. Other forms of TOS can be treated symptomatically.
  
  
• Whiplash. An injury to the soft tissues of the neck resulting from a sudden jerking of the head. In addition to neck pain, whiplash may cause shoulder pain, back pain and headaches.
  
  
• Polymyalgia rheumatica. A chronic inflammatory disease marked by muscle pain and stiffness around the neck, shoulders and hips.
  
  
• Cervical dystonia. A nerve disorder that causes severe muscle contractions in the neck and shoulder.
  
  
• Heart attack. Pain radiating from the chest to the shoulders, arms, neck or jaw may signal a heart attack (myocardial infarction). A heart attack can also cause shoulder pain without chest pain. Patients suspecting a heart attack are urged to seek immediate medical attention.
  
  
• Infection. Rarely, infection can be another source of pain and inflammation.
  
  
• Referred pain. Pain from the neck or other areas can be felt in the shoulder. Ectopic pregnancy (implanted outside the uterus) and certain conditions of the gallbladder, liver or diaphragm can be experienced as shoulder pain.

In diagnosing the source of shoulder pain, a physician will review the patient’s medical history and perform a physical examination. The physician will palpate (feel) the shoulder to try to detect physical signs of injury, and will look for limits of movement and the extent of joint instability or stiffness. The patient may be asked to complete a pain assessment.

In some cases, further testing will be necessary to pinpoint the cause of shoulder pain. Such tests may include:

• X-ray. Images may reveal more detail about the problem causing the pain. For example, the severity of a shoulder separation sometimes can be detected by taking an x-ray of the shoulder while the patient holds a light weight. This pulls on the muscle and makes the separation even more pronounced. However, traditional x-ray procedures cannot reveal all injuries.
  
  
• Arthrography. This x-ray procedure uses a contrast medium injected into the joint to outline the structures of the shoulder, such as the rotator cuff. The contrast fluid can indicate tears, openings or blockages.
  
  
• MRI (magnetic resonance imaging). This imaging technique provides cross-sectional images of the shoulder. It can be used to detect rotator cuff injuries and degenerative conditions of the shoulder, neck or spine. MRI or other imaging tests can sometimes avoid the need for arthroscopic examination.

• CAT scan (computed axial tomography). This test using multiple x-rays can detect many disorders of the joints, bones, muscles and internal organs.
  
  
• Bone scan or other radionuclide imaging. Nuclear medicine can be used to detect conditions such as bone diseases, hidden fractures and cancer.
  
  
• Blood tests. These may be ordered if infection or certain other conditions are suspected.
  
  
• Arthroscopy. A camera is inserted in the joint and visualized outside.  This procedure is usually done under general anesthesia and is performed when other diagnostic measures fail to make a diagnosis.

Patients who experience shoulder pain usually are urged to follow the four-step recovery regimen known as RICE – rest, ice, compression and elevation:

In many cases, this technique will reduce pain and inflammation and the shoulder will slowly heal. Over-the-counter anti-inflammatory medications may help reduce symptoms, although these medications should not be taken without first consulting a physician.

In some cases, medical attention will be necessary to ensure that the shoulder pain is correctly diagnosed and treated appropriately.  Professional medical attention is necessary if pain lasts more than one to two weeks despite self-care measures.  Patients should also seek prompt medical care if they experience a severe blow or injury that causes pain and swelling, significant bruising or bleeding of the shoulder, especially if there is a suspected fracture, dislocation or subluxation.  

Healthcare providers will treat shoulder problems differently, depending on the nature of the problem. Treatments used for various types of shoulder problems include:

• Dislocation. A physician first treats this condition by putting the ball of the humerus (long bone of the arm extending from the shoulder to the elbow) back into the joint socket. This procedure is known as a reduction. Intravenous (I.V.) medications can be given before reduction to reduce any discomfort. The arm is then immobilized in a sling or a shoulder immobilizer for a period of weeks. Patients are often urged to apply ice to the shoulder three or four times each day.

Once pain and swelling have been controlled, the patient may enter a rehabilitation program. In some cases, a shoulder that has dislocated becomes more susceptible to the same injury in the future. Surgery may be necessary to correct this flaw.

• Separation. In most case, separations are treated by putting the arm in a sling and having the patient rest the shoulder. Within two or three months, full healing typically occurs. The patient may be required to undergo a short period of physical therapy or occupational therapy afterward. Surgery may be necessary in situations where ligaments have been severely torn.
  
  
• Tendinitis, bursitis and impingement syndrome. Rest, applications of cold treatments (cryotherapy) and anti-inflammatory medications are usually the first approaches to treating these conditions. In some cases, therapeutic ultrasound or another form of thermotherapy may be used to warm deep tissues and stimulate blood flow.

If this approach fails to relieve symptoms, the patient may be treated with an injection of a corticosteroid. In some cases, tendinitis may become chronic and can lead to the rupture of a tendon. In these extreme cases such as where treatments produce no improvement after six to 12 months, surgery may be necessary to repair the tendon.

• Torn rotator cuff. Patients are usually asked to rest the shoulder and apply cold or heat to sore areas. Anti-inflammatory medication can also help soothe these tears. Other treatments include electrical stimulation of muscles and nerves, ultrasound and corticosteroid injections. Patients sometimes will be asked to wear a sling for a few days. They are also evaluated to determine the cause of the tear and eliminate or correct the action (e.g., heavy lifting or sports movement).

In many cases, arthroscopy or other surgery may be necessary to repair severe tears. Once the rotator cuff has healed, physical or occupational therapy follows to restore range of motion of the shoulder.

• Fracture. The physician will try to bring the bone back into a position that will speed healing and restore arm movement. For a nondisplaced fracture of the clavicle (collarbone), wearing a strap or sling is usually not recommended. When the clavicle is involved, patients may be asked to wear a strap or sling around their chest. This helps keep the clavicle in place.  Fracture of the neck of the humerus is usually treated with a sling or shoulder immobilizer. Surgery may be necessary in some of these cases.

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• Frozen shoulder. Treatment usually begins with anti-inflammatory drugs and application of heat. Stretching exercises may also be part of the routine. A technique called transcutaneous electrical nerve stimulation (TENS) may be used to block nerve impulses and reduce pain. Surgery to cut adhesions may be necessary in some cases. Physical or occupational therapy may be implemented to increase the mobility of the shoulder and reduce the pain.
  
  
• Arthritis of the shoulder. This condition is treated differently, depending on the type of arthritis that is present. Osteoarthritis (which typically occurs in older people due to wearing of the joints) is often treated with nonsteroidal anti-inflammatory drugs (NSAIDs). Rheumatoid arthritis may require physical or occupational therapy and additional medicines. Injection of corticosteroids into the joint can also cause temporary relief of pain.

In some cases, surgery may be necessary. For example, a worn shoulder joint can be replaced with an artificial ball for the top of the humerus and a cap on the scapula (shoulder blade). The success of joint replacement (arthroplasty) or other surgery often depends upon the condition of rotator cuff muscles before the surgery and how closely patients follow their rehabilitation regimen.

• Cervical dystonia. The U.S. Food and Drug Administration has approved injections of botulinum toxin type A (Botox) to treat this neuromuscular disorder.

Shoulder pain may sometimes indicate a more serious underlying health condition. For instance, sudden shoulder pain sometimes indicates a heart attack. Patients should seek immediate medical care if they experience sudden pressure or crushing pain in the shoulder, especially if it branches out to the chest, jaw, neck or down the arm. Medical attention is also necessary if the pain is accompanied by shortness of breath, dizziness or sweating. In cases of referred pain, treating the underlying condition would treat the shoulder pain also.

In many cases, shoulder pain cannot be prevented (e.g., injury, degenerative disorder). However, people can take several steps to reduce the likelihood of new injuries, or to prevent old injuries from recurring. These include:

• Practicing good posture and ergonomics at work and home to reduce risk of repetitive strain injuries and sudden trauma. For example, forearm support boards may help prevent shoulder, arm and neck pain and injury in computer users.

• Using ice (cryotherapy) and ibuprofen after exercising if there is a history of shoulder pain.
  
  
• Working with a physical therapist or physician to design an exercise routine that can stretch and strengthen rotator cuff tendons (tough, inelastic fibrous tissue that connects muscle with its bony attachment) and shoulder muscles.
  
  
• Performing range-of-motion exercises when recovering from tendinitis. This can help prevent development of frozen shoulder.
  
  
• Using proper technique when participating in athletics to prevent shoulder problems.
  
  
• Completing stretching exercises before and after athletics to reduce the chance of shoulder pain.

Preparing questions in advance can help patients have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions about shoulder pain:

1. What types of injuries might be causing my shoulder pain?
   
   
2. I’ve been treating this at home, but it’s not getting better. How long should I wait before scheduling a doctor’s appointment?
   
   
3. How do I know if I have a tear in a ligament, tendon or muscle?
   
   
4. Will an x-ray or other test show if there is anything wrong with my shoulder?
   
   
5. What are my treatment options?
   
   
6. Are there medications that can help prevent my pain?
   
   
7. Will I need surgery?
   
   
8. Can occupational therapy or physical therapy help me?
   
   
9. What is the best way to prevent my injury from recurring?
   
   
10. Can I do exercises at home to help my shoulder?