Rheumatoid Foot Deformity

In Rheumatoid arthritis (RA), the immune system attacks healthy joints. Joint lining becomes inflamed, causing pain, swelling, and redness. Over time, relentless inflammation can damage the cartilage and bones of the feet, leading to foot deformity.

The many joints of foot are enclosed in a fibrous capsule lined with a thin membrane known as synovium, which secretes a fluid that lubricates joints.3

Rheumatoid arthritis attacks synovial tissue in joints, causing pain, inflammation, and damage. It can affect the ankle, heel (hindfoot), arch (midfoot), ball, toes (forefoot), and connective tissue

RA can affect

• Abnormal foot flattening
• Midfoot and forefoot instability
• Excessive weight-bearing on the inside of the foot
• Foot rolling onto the outer edges

This can shift weight distribution and cause:

• Joint pain
• Soft tissue problems
• Corn and callus

All of these issues, together, can lead to foot deformities.

Forefoot Deformities

RA can cause several problems in the forefoot. An early sign is often dislocation of the MTP joints. As the disease progresses, it can lead to some common deformities involving forefoot bones and joints.

MTP Joint Dislocation

MTP joint dislocation is caused by inflammation of the synovium, which occurs because of the immune system attack that occurs with RA.

It causes swelling and pain that's typically felt on the sole of the foot or on the top near the MTP joint. Pain is often exacerbated by wearing shoes.

Hammertoe

When an MTP joint—usually of the second, third, or fourth toe—becomes misaligned (and goes untreated), it can take on a claw-like appearance called hammertoe..

Hammertoe causes pain in the bent toe and in the ball of the foot underneath the affected joint.

Crossover Deformity

A crossover deformity of the toes is a type of hammertoe. This problem usually impacts the second toe and causes it to cross over the big toe.1

Bunions

they typically develop as a result of abnormal pressure on the first MTP joint.

Midfoot Deformities

Your midfoot is the arch of your foot. RA can damage the cartilage in this region and cause pain that may be exacerbated by wearing shoes. It can also cause flatfoot deformity.

Flatfoot

Your arch is supported by ligaments that maintain its curved shape. However, with RA, these ligaments can become weak and collapse. This will develop flatfoot.

The flatfoot deformity can change the shape of your feet, put pressure on joints and other structures, and cause considerable pain.

Rheumatoid nodules and soft-tissue disorders are common.

Rheumatoid Nodules

Rheumatoid nodules on the Achilles' tendon, which runs from the back of your heel up to your calf, are a common problem.

These are small masses of inflammatory tissue that appear either alone or in clusters. They can appear in several places throughout the body and may feel rubbery, though they are more likely to feel firm when on a tendon, such as the Achilles' tendon. Rheumatoid nodules usually move around when you push on them.

Diagnosis

Blood Investigation- CBC, ESR,CRP, RA , Uric acid, ACCP

Radiological Investigation- X-rays, MRI

Management

RA is typically treated with DMARDs, which address the underlying causes of inflammation, slow disease progression, and help prevent future damage and deformity.

Beyond that, surgery may help you depends on the type of foot therapeutic footwear can reduce pain and improve function.