Rheumatoid arthritis (RA) is an inflammatory autoimmune disease that progressively damages joints and can eventually lead to joint deformities. Joint deformities occur when the joints lose their shape and alignment. Deformities can lead to complete loss of joint function and disability.

Although there currently is no cure for RA, there are medications and treatments available that can slow its progression — including the development of joint deformities. Once a joint deformity occurs, a person living with RA may benefit from treatments to manage the associated inflammation and symptoms. Joint replacement surgery may become necessary if there is too much damage.

How Does RA Cause Joint Deformity?

Normally, healthy joints are lined with a specialized membrane known as the synovium. The synovium produces synovial fluid that lubricates and protects the joints. In RA, immune cells attack the synovium and release specialized inflammatory proteins known as cytokines. Inflammation of the synovium, called synovitis, develops as a result. Another condition, known as tenosynovitis, can occur when the synovium surrounding a tendon becomes inflamed.

The inflammation triggers the synovial membrane to grow abnormally fast, creating a fibrous layer of abnormal tissue, known as a pannus. The pannus releases enzymes that break down cartilage and bone, which can destroy the joints and ligaments. The abnormal tissue also contains a large number of specialized bone cells known as osteoclasts, which secrete high levels of other proteins and acids that erode the bone. The pannus can also produce too much synovial fluid, which contributes to joint swelling and pain.

Over time, this inflammatory damage can lead to joint deformities.

What Are the Common Deformities That Can Develop in People With RA?

RA is typically found in the small joints in the hands, feet, and wrists. In the hands, the knuckles (metacarpophalangeal joints) and middle finger joints (proximal interphalangeal joints) are most often affected. The outermost finger joints (distal interphalangeal joints) are usually unaffected. Several types of joint deformities may result, including the following:

• Boutonniere deformity — The middle joint of a finger is bent and will not straighten, while the tip of the finger bends back.
• Swan-neck deformity — The base of the finger and the outermost finger joint bend inward (in flexion), while the middle joint is straightened out (in extension).
• Hitchhiker’s thumb — The thumb knuckle flexes outward abnormally, while the outermost finger joint hyperextends. It’s also known as a Z-thumb, because it creates a Z shape.
• Ulnar drift — Also known as ulnar deviation, this condition describes when the fingers angle away from the thumb toward the ulna bone in the forearm. Ulnar drift is due to severe damage in the knuckles of the fingers. Read more about ulnar drift here.
• Carpal tunnel syndrome — This affects the wrists. The inflammation in the wrist and hand can compress the nerve leading to the hand and fingers, causing weakness.
• Claw toe deformity — With this deformity, the toes are bent either upward (in extension) or down (in flexion) from the joints at the ball of the foot. Sometimes, the toes may also bend and curl under the foot.
• Rheumatoid nodules — These are firm lumps that develop in the bony joints of people with RA. Read more about rheumatoid nodules here.

Can Joint Deformities Be Prevented?

Although there are no medications available to prevent RA, disease-modifying antirheumatic drugs (DMARDs) can help slow disease progression. These drugs work by targeting inflammation at its source to help stop further joint damage and prevent disability associated with joint deformities.

Examples of DMARDs include:

• Otrexup, Rasuvo, and Trexall (methotrexate)
• Arava (leflunomide)
• Azulfidine (sulfasalazine)
• Plaquenil (hydroxychloroquine)

Biologics are drugs that contain man-made proteins that decrease inflammation by blocking specific immune cells or inflammatory proteins to dampen the immune system. Examples of biologics used to treat RA include:

• Actemra (tocilizumab)
• Cimzia (certolizumab pegol)
• Enbrel (etanercept)
• Humira (adalimumab)
• Kevzara (sarilumab)
• Orencia (abatacept)
• Remicade (infliximab)
• Rituxan (rituximab)
• Simponi (golimumab)

Targeted synthetic DMARDs alter cellular signaling and decrease inflammation, and they include:

• Olumiant (baricitinib)
• Rinvoq (upadacitinib)
• Xeljanz (tofacitinib)

Steroids (also known as corticosteroids) can also be used to manage acute symptoms of RA while reducing inflammation. Steroids work by mimicking the action of cortisol, the natural stress chemical that reduces inflammation. Doctors may prescribe corticosteroids such as prednisone to help manage RA symptoms while waiting for DMARDs or other medications to begin fully working.

How Can Joint Deformities Be Treated?

Aggressive treatment with medication may help prevent deformities. However, once joint deformities occur, treatments mainly focus on managing inflammation and symptoms through therapy. Surgery can also sometimes address pain and help people with joint deformities regain some functionality.

Occupational Therapy

Joint deformities can limit the ability to use your hands, making many tasks difficult. An occupational therapist can work with you to develop an exercise program to help improve the function and slow the progression of the deformity. The therapist may also suggest using splints to stabilize the affected joints in the hands, wrists, and fingers.

Surgery

If medications are not effective or if there is too much joint damage, surgery may be a good treatment option. Although surgery won’t cure RA, it can remove and replace the damaged joints and tissues, which can help you recover some functionality. Your doctor may suggest one of several surgery options.

• Total joint replacement (arthroplasty) — Here, the damaged areas of the joint are removed (or in some cases, reshaped), then replaced with prosthetic parts made from plastic, metal, or ceramic.
• Joint fusion (arthrodesis) — The damaged cartilage is removed and the two bones are fused together with a metal fixation device. This procedure helps to stabilize or realign a joint and relieve pain in situations where a joint replacement is not recommended.
• Synovectomy — This procedure entails removing the inflamed synovium to help treat pain and restore mobility. A surgeon can do a synovectomy using arthroscopy, in which the surgeon makes only a small cut near the joint and uses a thin tube with a camera attached to help perform the surgery.
• Tendon repair — Damaged or ruptured tendons from tenosynovitis can be removed during a tendon repair in a procedure similar to a synovectomy.

Connect With Others Who Understand

By joining myRAteam — the social network for people with rheumatoid arthritis and their loved ones — you can connect with more than 147,000 members who understand life with RA. Every day, members come together to ask questions, give advice, and share their stories.

Is your RA causing joint deformity? Share your experience in the comments below, or start a conversation on myRAteam.