How Does Rheumatoid Arthritis Affect the Shoulders?

Rheumatoid arthritis (RA) is known for causing all-over inflammation and pain. It happens when the immune system malfunctions and attacks the synovium, the lining of the joints.

RA can target the synovial lining of the shoulder joint. Because RA is a symmetrical condition—affecting the same joints on both sides of the body—people with shoulder RA often experience pain and swelling in both shoulders at once. Shoulder RA may cause erosion and deformity of the shoulder joints over time.

People with RA have an increased risk of shoulder problems as a consequence of ongoing inflammation. While the numbers of people with shoulder problems in the general population are smaller, people with RA will have notable shoulder tenderness and swelling as early as two years after diagnosis.

After the first two years, 5% of people with RA will report shoulder pain, and after 12 years of living with the condition, 96% will have erosive shoulder damage.

About the Shoulder Joint

The shoulder is made up of three bones: the humerus (the upper arm bone), the clavicle (collarbone), and the scapula (shoulder blade). There are two joints in the shoulder that help it to move: the acromioclavicular joint and the glenohumeral joint.

The acromioclavicular joint is located where the highest point of the scapula meets the clavicle. The glenohumeral joint is the ball and socket joint between the scapula and humerus.

A combination of muscles and tendons—called the rotator cuff—keep the arm centered into the shoulder socket. The joints of the shoulder are protected by the synovium, which also lubricates them and makes them easier to move.

Damage to the shoulder joints is often caused by inflammation or injury to the cartilage of the shoulder joint. Cartilage breakdown can affect both the glenohumeral joint and the acromioclavicular joint.

Signs and Symptoms

People with RA who have shoulder involvement will have pain in both shoulders.

Additional shoulder symptoms experienced with RA may include:

• Tenderness and warmth
• Stiffness, especially in the morning upon waking
• Rheumatoid nodules under the skin of the shoulders and arms
• Reduced range of motion
• Reduced muscle strength
• Fatigue, fever, or weight loss, resulting from severe shoulder inflammation
• Crepitus—grinding, clicking, or cracking notices of the joints
• Lock-up of the shoulder because the surfaces lining the joint are no longer smooth or slide in certain positions
• Pain aggravated by activity

Shoulder involvement tends to be worse in people who have long-term RA and who are older at the onset of the disease. As shoulder involvement worsens, movement of the shoulder gets harder and there may be significant pain. Night pain is common and makes it harder to sleep.

Shoulder Conditions Linked to RA

Rheumatoid arthritis has been linked to other shoulder conditions because of chronic inflammation. This includes rotator cuff degeneration and tears, frozen shoulder syndrome, and bursitis. 

Rotator Cuff Degeneration

The rotator cuff is a group of four tendons that stabilize the shoulder joint. These tendons connect to four muscles that help to move the shoulder in various directions.

Research shows that people with RA have a higher risk of rotator cuff degeneration and tears. Ongoing RA inflammation can cause the rotator cuff to become damaged.

Frozen Shoulder Syndrome

Also known as adhesive capsulitis, frozen shoulder is characterized by shoulder pain and stiffness. RA is significantly associated with frozen shoulder, and people with systemic conditions like RA have the highest risk for the condition.

Symptoms will begin gradually and eventually get worse. Over time, frozen shoulder causes shoulder movement to become harder. The condition tends to resolve within three years.

Treatment for frozen shoulder can help resolve symptoms, reduce pain, and improve range of motion and muscle strength in the affected shoulder.

Bursitis

Bursitis causes inflammation of the bursae, the small, fluid-filled sacs found near the joints. Bursitis of the shoulder causes painful inflammation of the shoulder joint extending into the upper arm.

Bursitis pain increases with movement, especially with lifting the arms above the head. RA is known for causing bursitis because of the ongoing inflammation it produces.

Diagnosis

Your healthcare provider can make a diagnosis of shoulder RA by looking at your symptoms, medical history, and overall health.

Your healthcare provider will also perform a physical examination, which will look for:

• Signs of a previous injury, including to the muscles, tendons, and ligaments around the joint
• Weakness of the shoulder muscle
• Pain when pressure is applied to the joint
• Involvement of other joints
• A grating sound when the joint is moving
• Tenderness
• Diminished range of motion

Your healthcare provider will also order X-rays to look for narrowing of the joint space, changes to bone, and the formation of bone spurs.

Another method of diagnosis involves injecting a local anesthetic to the shoulder joint. If the injection helps relieve pain, then a diagnosis of RA in the shoulder joint can be made.

Treatment

Your healthcare provider will treat RA-related shoulder problems first by managing the source of them, which is ongoing inflammation. This might mean changes to your RA treatment plan.

Shoulder symptoms will also be treated separately. Treatment for shoulder RA may include range of motion exercise, pain control, lifestyle modifications, and as a last resort, surgery.

Range of Motion Exercise

Treatment for shoulder RA often starts with range of motion exercises to keep your shoulder mobile. If range of motion has not been affected, the goal will be to prevent things from getting worse. Physical therapy can be helpful in teaching you exercises to strengthen your shoulders and improve range of motion.

Assistive Devices

Your physical or occupational therapist may suggest assistive devices to help you with tasks that have become harder. One popular device is a reacher, which helps you to remove and replace objects from high places without having to lift your arm. There are also assistive devices that can help you get dressed, such as zipper pulls and dressing sticks.

Pain Control

Pain control can be done in several ways. Ice packs, for example, are great for managing pain and can be used as needed. Heating pads can also help treat shoulder pain and relax pain and stiffness in the shoulder.

Medications—available over the counter or prescribed by your healthcare provider—may be used to control pain. You should discuss with your practitioner all the benefits and potential complications of medications you are using to manage shoulder pain.

Your healthcare provider may recommend injections to offer pain relief for shoulder RA. There are two types of injections that are used to treat shoulder RA. The first type is a cortisone shot. It is given directly into the shoulder joint and can offer pain relief and reduce inflammation.

Another type of injection for treating shoulder RA contains hyaluronic acid— a substance similar to the one that occurs naturally in the joints. Hyaluronic acid works by acting like a lubricant and shock absorber to keep the joints moving properly. A hyaluronic injection can improve pain for weeks or even months.

Lifestyle Modifications

Your healthcare provider may suggest you avoid or cut off activities that make your shoulder painful, especially if the pain is affecting you on a daily basis or keeps you up at night.

For example, if you play a sport that requires shoulder and arm movement, you may want to stop doing it or cut down on how often you play that sport. Or if your job requires lifting, you may want to ask your employer for light-duty where you are not doing as much lifting or carrying of heavy objects.

Surgery

In some cases of shoulder RA, surgery might be needed for people who don’t respond to nonsurgical therapies. Surgical options may include shoulder replacement surgery, the fusion of affected joints, and partial removal of inflamed synovium.

A Word From Verywell

Talk to your healthcare provider if you have rheumatoid arthritis and start to develop shoulder pain or other shoulder symptoms. Since these symptoms can get worse with time, you shouldn’t ignore them. Your practitioner can order imaging and bloodwork to help determine the source of shoulder pain and symptoms.