Causes of Shoulder Pain

Shoulder pain refers to sensitivity in and around the shoulder joint. The shoulder is not a single joint but a group of joints held and connected by tendons and muscles. This arrangement allows the arms a wide range of motion. While this mobility is an advantage, it also brings a vulnerability: because of its structure the shoulder can become unstable. In addition, painful conditions can develop due to impingement between soft tissues and bones.

Shoulder pain may appear when moving the arm, when lying down, or it may be constant. It can be transient, recurrent, or continuous.

The pain can originate from the shoulder joint itself or from any of the surrounding muscles, ligaments and tendons. It can be caused by tension (stress), muscle spasm, overuse, injury or inflammation. This pain usually worsens with even small movements of the arm or shoulder.

Various diseases and conditions affecting the chest or abdominal organs, such as heart disease or gallbladder disease, can also cause shoulder pain. In such cases we call it “referred” pain; however, this type of pain does not change or intensify with shoulder movement.

Below I list the most common causes (presented in alphabetical order).

Possible causes of shoulder pain

Frozen shoulder

A condition characterized by stiffness and pain in the shoulder joint. The connective tissue surrounding the joint thickens and tightens. Signs and symptoms usually begin gradually, worsen over time, and typically resolve within 1–3 years.

Risk increases if you are recovering from an illness or procedure that prevents you from moving your arms—for example after a stroke or mastectomy (breast removal surgery).

Brachial plexus injury

The brachial plexus is the network of nerves that sends signals from the spinal cord to the shoulder, arm and hand. Injury occurs when these nerves are stretched, compressed, or in the most severe cases, torn or avulsed from the spinal cord.

Milder brachial plexus injuries occur in contact sports. Infants can suffer such an injury during birth in the birth canal. Other conditions, such as inflammation or tumors, can also affect the integrity of the brachial plexus.

The most severe injuries usually result from car, motorcycle and bicycle accidents. In serious cases the arm may become paralyzed, but surgery can help restore some function.

Bursitis (inflammation of the joint bursa)

Bursitis affects the small, fluid-filled sacs called bursae that cushion bones, tendons and muscles near joints and reduce friction between moving parts of the body. Bursae become inflamed in bursitis.

It most commonly affects the shoulder, elbow and hip, but can also occur at the knee, heel and the base of the big toe. It often occurs near joints that perform repetitive motions.

Treatment typically involves resting the affected joint and protecting it from further injury. In most cases, bursitis pain resolves within a few weeks with appropriate treatment, although recurrent flare-ups are common.

Dislocation

An injury in which the upper arm bone pops out of the cup-shaped socket that is part of the shoulder blade. The shoulder is the most mobile joint in the body and therefore prone to dislocation.

In a dislocation the joint ligaments stretch so much that the bones forming the joint come out of place. The shape and contour of the joint changes and movement is severely limited. Intense pain and swelling occur.

Impingement syndrome (thrower's shoulder)

Also known as shoulder impingement, swimmer's shoulder or thrower's shoulder. The condition is caused by impingement of the rotator cuff tendons as they pass through the shoulder joint. It often develops after partial tearing of the rotator cuff tendons or gradually due to persistent overuse and overload.

Tendinitis (tendon sheath inflammation)

Inflammation or irritation of the tendons—the thick fibrous “cords” that attach muscle to bone. This condition causes pain and tenderness close to the joint.

It can occur in any tendon but is most common around the shoulder, elbow, wrist, knee and heel. Some common names for various tendinous problems include:

• Tennis elbow
• Golfer's elbow
• Thrower's shoulder
• Swimmer's shoulder
• Jumper's knee (patellar tendinitis)

Most cases are successfully treated with rest, physiotherapy and pain-relieving medication. If severe and leading to tendon rupture, surgery may be required.

Tendon rupture

Arm fracture

A fracture affects one or more of the three bones of the arm—the ulna, the radius and the humerus. One of the most common causes of an arm fracture is falling onto an outstretched hand.

In such cases seek medical attention immediately. It is important that the fracture be treated as soon as possible to ensure proper healing.

Therapy depends on the location and severity of the injury. A simple fracture may be managed with splinting, icing and rest. However, a bone may need to be realigned (reduced) in the emergency department.

A more complex fracture may require surgery to rejoin the broken bone, and insertion of wires, plates, pins or screws to keep the bone properly aligned during healing.

Clavicle fracture

A common injury, especially in children and young adults. The clavicle connects the upper part of the breastbone to the shoulder blade. Frequent causes of clavicle fractures include falls, sports injuries and trauma from road accidents, which produce pain and swelling at the fracture site. Infants' clavicles can also be injured during birth.

If you suspect a fractured clavicle, seek medical attention immediately. In most cases the condition heals well with icing, pain management, immobilization, physiotherapy and time. A complex fracture may require surgery to realign the broken bone and insert plates, screws or rods to hold it in place during healing.

Thoracic outlet syndrome

A group of disorders that occur when blood vessels or nerves in the space between the clavicle and the first rib (the thoracic outlet) are compressed. This narrow passage is filled with blood vessels, nerves and muscles; when compressed it can cause pain in the shoulder and neck, and produce numbness in the fingers.

Common causes include physical trauma from a car accident, repetitive strain from work or sports activities, certain anatomical defects (such as an extra rib), and pregnancy. Sometimes doctors cannot determine the exact cause.

Treatment usually involves physiotherapy and pain management. Most people improve with these therapies, but in some cases surgery may be necessary.

Avascular necrosis

The death of bone tissue due to lack of blood supply. Also known as osteonecrosis, it can lead to tiny fractures in the bone, which ultimately cause the bone to collapse.

A broken bone or a dislocated joint can interrupt the blood supply to a part of the bone. Avascular necrosis is also associated with long-term use of high-dose steroid medications and excessive alcohol consumption.

It can affect anyone, but most often occurs in people between the ages of 30 and 50.

Cervical radiculopathy

A herniated disc in the neck or upper spine can cause radiating pain toward the shoulder, arm and hand. This pain is called cervical radiculopathy or a pinched nerve.

Cervical radiculopathy can produce burning or tingling sensations and weakness in the arm, shoulder or hand. In more severe cases it can lead to loss of sensation and paralysis.

Osteoarthritis

The most common form of arthritis, affecting millions of people worldwide. It develops when the protective cartilage cushioning the ends of the bones deteriorates. It can affect any joint but most often involves the hands, knees, hips and spine.

Symptoms are generally manageable, although joint damage cannot be reversed. An active lifestyle, maintaining a healthy weight and certain treatments can slow disease progression and help reduce pain and improve joint function.

Polymyalgia rheumatica

An inflammatory condition that causes muscle pain and stiffness, particularly in the shoulders and hips. Signs and symptoms usually develop quickly and are typically worse in the morning.

Most people who develop polymyalgia rheumatica are older than 65; it rarely affects those under 50.

It is often associated with another inflammatory disease called giant cell arteritis, which causes headaches, visual problems, jaw pain and scalp tenderness. Both conditions may occur together.

Sprain

A ligament or ligaments that support a joint are overstretched by a sudden twist or injury. Ligaments are strong bands of tissue that hold joints together and help prevent excessive movement.

Ligament injuries are most common in the ankle, particularly the three ligaments on the outside of the ankle, occurring when the ankle rolls or twists excessively.

Sprains are also common in the shoulder joint.

With a sprain, the injured area should be rested immediately; rest, ice, compression (bandaging) and elevation are recommended. Sprains are usually treatable at home; modalities such as softlaser or microcurrent therapies can support regenerative processes. Surgery may be necessary in severe cases if ligaments are torn.

Rotator cuff injury

The rotator cuff is a group of muscles and tendons that surround the shoulder joint and firmly hold the head of the humerus in the shoulder socket. Rotator cuff injuries cause a dull ache that often worsens when the arm is moved away from the body. Severity ranges from simple inflammation to complete tendon rupture, resulting in pain, weakness and reduced range of motion.

This type of injury is common and becomes more frequent with age. It may occur earlier in people whose work involves repeated overhead arm lifting, such as painters and carpenters.

Many people with rotator cuff problems can manage their symptoms well and return to daily activities with physiotherapy exercises that improve the flexibility and strength of the muscles around the shoulder joint.

Sometimes a rotator cuff tear occurs from a single injury. In such cases seek medical evaluation as soon as possible so healthcare professionals can discuss the potential role of surgery in a timely manner.

Heart attack (myocardial infarction)

Occurs when the flow of blood to the heart is blocked. Most often this is caused by the buildup of fat, cholesterol and other substances that form a plaque in the coronary arteries that supply the heart.

Sometimes a blood clot forms that completely blocks blood flow. The resulting lack of oxygen can damage or destroy part of the heart muscle. This is a heart attack, also known as myocardial infarction.

The main symptom is a pressure-like (squeezing) pain in the chest. It most commonly radiates to the left arm, shoulder, beneath the shoulder blade, the back or the upper abdomen. Moving the arm does not change the pain.

A heart attack can be fatal, but treatment has advanced significantly over the years. It is crucial to call emergency services if you think you may be having a heart attack.

Septic arthritis

A painful infection in a joint caused by bacteria that spread through the bloodstream from another part of the body. It can also occur when bacteria are directly introduced into the joint by a penetrating injury, such as an animal bite or trauma.

It is most likely to occur in infants and older adults. People with artificial joints are also at increased risk. The knee is most commonly affected, but the hip, shoulder and other joints can also be involved. Infection can rapidly and severely damage cartilage and bone in the joint, so immediate treatment is critical.

Treatment involves draining the joint with a needle or surgical procedure. Antibiotics are usually required for full recovery.

The causes presented above are often associated with shoulder pain symptoms. However, for an accurate diagnosis you should always consult a physician. Only knowing the cause allows appropriate therapy to be applied.

When to see a doctor?

Seek immediate medical help if you experience shoulder pain accompanied by difficulty breathing or chest pressure. This may be a symptom of a heart attack and requires urgent medical attention.

Similarly, if your shoulder pain was caused by an injury and any of the following accompany it:

• The joint looks deformed.
• You cannot use the shoulder joint or move your arm away from the midline of your body.
• Severe pain.
• Sudden swelling.

Make an appointment for evaluation if your shoulder pain is accompanied by:

• Swelling
• Redness
• Sensitivity and warmth around the joint.

Although the shoulder sits in a relatively loose joint capsule, its structure makes it a difficult-to-access joint. It is hard to deliver active ingredients to the affected area with topical ointments or creams in the event of any health problem or inflammation. The body itself also has difficulty providing increased metabolism and blood supply to this area. Therefore, for shoulder joint inflammations the most reliable and quickest healing is achieved with local treatments. These act where the problem has developed. This way you do not burden the whole body unnecessarily and you can support healing more effectively.