An Overview of Arthritis Mutilans

Arthritis mutilans is a severe form of chronic rheumatoid arthritis or psoriatic arthritis and one of the most advanced types of joint disease overall. It is characterized by severe inflammation that damages the joints of the hands and feet, causing deformity and the loss of use. Less commonly, it can affect the spine and lead to changes in posture and mobility. Early and aggressive treatment of arthritis mutilans is important and should start at the time of diagnosis. 

Arthritis mutilans is considered rare, affecting less than 5% of people with psoriatic arthritis and around 4.4% of people with rheumatoid arthritis, according to a 2008 study from the Baylor College of Medicine.

Causes

Essentially, arthritis mutilans is simply an autoimmune disease turned on high. While all autoimmune diseases are characterized by inflammation, only rheumatoid arthritis and psoriatic arthritis are subject to the extremes seen with arthritis mutilans. Scientists are unsure why this is and why some people are more susceptible to arthritis mutilans than others.

Part of the reason may be that rheumatoid arthritis and psoriatic arthritis cause similar types of inflammation. They even need a differential diagnosis to tell one from the other.

Rheumatoid arthritis is defined by an autoimmune assault on the joints, causing pain, swelling, redness, and the gradual restriction of movement. It can be diagnosed with blood tests that detect the presence of rheumatoid factor (RF), and anti-cyclic citrullinated peptide (Anti-CCP), autoantibodies found in most people with the disease.

Psoriatic arthritis is an autoimmune disorder integrally linked to psoriasis. Psoriasis specifically targets skin cells, triggering inflammation and the production of dry, scaly lesions. Psoriatic arthritis occurs when that inflammation also attacks the joints and surrounding structures.

Psoriasis not only develops differently than rheumatoid arthritis (asymmetrically rather than symmetrically) but also has no blood tests to confirm its presence.

The inflammation is severe enough to accelerate cartilage and bone mineral loss, leading to a collapse of the joint space. It also causes the buildup of fibrous tissues (known as pannus) around the joint, which is what leads to deformity.

Symptoms

The term mutilans is derived from the Latin for "mutilated" or "maimed." As such, the main symptoms of arthritis mutilans are:

• Joint deformity
• Loss in range of motion (ROM)

This can interfere with your ability to perform everyday tasks like fastening buttons and opening jars.

Arthritis mutilans may also lead to "telescoping fingers" in which the connective tissues can no longer support the joints, causing them to retract in a heap-like fashion. In some cases, the joints will fuse—a condition referred to as ankylosis—causing immobility and the fixation of the joint. 

Arthritis mutilans may also lead to “opera-glass hand” in which the connective tissues can no longer support the finger joints, causing them to retract in a heap-like fashion (“telescoping fingers”). In some cases, the joints will fuse—a condition referred to as ankylosis—causing immobility and the fixation of the joint. Signs of opera-glass hand include:

• Fingers that are significantly shortened or stretched
• Finger skin that is stretched, wrinkled, and shiny-looking

Others may develop a "pencil-in-cup deformity," so named because on X-ray images the ends of the bones will narrow like the tip of a pencil while the adjoining bone will be worn down into a cup-like shape.

Diagnosis

Arthritis mutilans is primarily diagnosed with imaging tests such as X-rays and computed tomography (CT). Magnetic resonance imaging (MRI) is far better at imaging soft tissues and is useful in measuring cartilage loss and the formation of pannus.

Blood work can help confirm the underlying cause, measure inflammation, and evaluate disease progression. Results can help direct appropriate medical treatment and monitor your response to it.

Treatment

Early treatment almost always confers to better results, slowing the progression of the disease and maintaining the highest quality of life possible.

Aggressive physical therapy, especially in the hands, can delay the disease’s progress and halt severe joint damage. Splinting may also help with joint stabilization, but it is typically used for short periods of time to avoid muscle atrophy.

High doses of nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen) or Celebrex (celecoxib) can help relieve inflammation and pain. Oral and intra-articular injections of corticosteroids can do the same, but are used sparingly to avoid long-term side effects.

Especially severe cases may benefit from tumor necrosis factor (TNF) inhibitor drugs like Humira (adalimumab) and Enbrel (etanercept). These biologic drugs help temper the effects of TNF, reducing the overall inflammation that contributes to joint damage.

Coping

Arthritis mutilans can be painful and debilitating, but it doesn't mean you can't take control of your life. A commitment to early and ongoing physical therapy is key. This may include hand therapy, occupational therapy, and even mind-body therapies (like meditation and guided imagery) to reduce stress and your emotional response to pain.

You should also find support to avoid isolation and depression common in people with arthritis. This may include your medical team, family, friends, or support groups located either online, through community health centers, or via non-profit associations like Creaky Joints.

Good self-care is also important. This includes a healthy diet, routine exercise, and the cessation of smoking. Smoking can interfere with your medications and promote inflammation that accelerates the progression of the disease.

A Word From Verywell

There is no set course for arthritis mutilans and no way to predict how severe it may become. What is known is that any damage done to the bone and cartilage is essentially permanent. Although surgery can help improve joint function, what is lost is ultimately lost. With this in mind, it's essential that you act once the signs of arthritis develop, particularly if someone in your family has rheumatoid arthritis or psoriatic arthritis.