Rheumatoid arthritis is a chronic disease that attacks multiple joints throughout the body. It most often starts in the small joints of the hands and feet, and usually affects the same joints on both sides of the body.

More than 90% of people with rheumatoid arthritis (RA) develop symptoms in the foot and ankle over the course of the disease.

The joints of your body are covered with a lining — called synovium — that lubricates the joint and makes it easier to move. Rheumatoid arthritis causes an overactivity of this lining. It swells and becomes inflamed, destroying the joint, as well as the ligaments and other tissues that support it. Weakened ligaments can cause joint deformities — such as claw toe or hammer toe. Softening of the bone (osteopenia) can result in stress fractures and collapse of bone.

Rheumatoid arthritis is not an isolated disease of the bones and joints. It affects tissues throughout the body, causing damage to the blood vessels, nerves, and tendons. Deformities of the hands and feet are the more obvious signs of RA. In about 20% of patients, foot and ankle symptoms are the first signs of the disease.

Trophic ulcer is a rapidly growing issue, especially in the older age groups. It develops as a result of ischemic necrosis and skin ulceration and can also affect deeper tissue structures in areas which are more exposed to pressure, especially if there is a bone just under the skin.

Trophic ulcers occur in diseases and injuries to the spinal cord and peripheral nerves; for example, they may arise on the foot after injury to the sciatic nerve. The ulcers are characterized by rapid progression of the ulcerative-necrotic process and by a refractory course. Ulcers of any origin are said to be trophic if they develop in a protracted course of a disease as a result of local secondary inflammatory, cicatricial, or other changes in small nerve branches; for example, they may result from injuries of local circulatory impairment, as in varicose veins of the legs. Treatment is determined by the main disease. Salves and physical therapy may be prescribed.

Apart from old age, the most common risk factors for development of trophic ulcer are urinary incontinence, diabetes, spine trauma, peripheral circulation diseases and multiple sclerosis.

Peripheral neuropathy describes damage to the peripheral nervous system, the vast communications network that transmits information from the brain and spinal cord (the central nervous system) to every other part of the body. Peripheral nerves also send sensory information back to the brain and spinal cord, such as a message that the feet are cold or a finger is burned.

Damage to the peripheral nervous system interferes with these vital connections. Like static on a telephone line, peripheral neuropathy distorts and sometimes interrupts messages between the brain and the rest of the body. Because every peripheral nerve has a highly specialized function in a specific part of the body, a wide array of symptoms can occur when nerves are damaged. Some people may experience temporary numbness, tingling, and pricking sensations (paresthesia), sensitivity to touch, or muscle weakness. Others may suffer more extreme symptoms, including burning pain (especially at night), muscle wasting, paralysis, or organ or gland dysfunction. People may become unable to digest food easily, maintain safe levels of blood pressure, sweat normally, or experience normal sexual function. In the most extreme cases, breathing may become difficult or organ failure may occur.

Some forms of neuropathy involve damage to only one nerve and are called mononeuropathies. More often though, multiple nerves affecting all limbs are affected-called polyneuropathy. Occasionally, two or more isolated nerves in separate areas of the body are affected-called mononeuritis multiplex.

In the most common forms of polyneuropathy, the nerve fibers (individual cells that make up the nerve) most distant from the brain and the spinal cord malfunction first. Pain and other symptoms often appear symmetrically, for example, in both feet followed by a gradual progression up both legs. Next, the fingers, hands, and arms may become affected, and symptoms can progress into the central part of the body. Many people with diabetic neuropathy experience this pattern of ascending nerve damage.

Most foot problems that people with diabetes face arise from two serious complications of the disease: nerve damage and poor circulation. One of the more critical foot problems these complications can cause is Charcot arthropathy, which can deform the shape of the foot and lead to disability.

Diabetes also damages blood vessels, decreasing the blood flow to the feet. Poor circulation weakens bone, and can cause disintegration of the bones and joints in the foot and ankle. As a result, people with diabetes are at a high risk for breaking bones in the feet.

When a diabetic fractures a bone in the foot, he or she may not realize it because of nerve damage. Continuing to walk on the injured foot results in more severe fractures and joint dislocations. Sharp edges of broken bone within the foot can point downward toward the ground, increasing the risk of chronic foot sores from the abnormal pressure.

There are treatment options for the wide range of diabetic foot problems. The most effective treatment, however, is prevention. For people with diabetes, careful, daily inspection of the feet is essential to overall health and the prevention of damaging foot problems.

Nerve damage (neuropathy) is a complication of diabetes that leads to a loss of sensation in the feet. Some people with diabetes can no longer feel when something has irritated or even punctured the skin. A wound as small as a blister can progress to a serious infection in a matter of days. The combination of bone disintegration and trauma can warp and deform the shape of the foot. This condition is called Charcot arthropathy, and is one of the most serious foot problems that diabetics face.

Although a patient with Charcot arthropathy typically will not have much pain, they may have other symptoms. The most sensitive sign of early Charcot foot is swelling of the foot. This can occur without an obvious injury. Redness of the foot can also occur in the early stages. The swelling, redness, and changes to the bone that are seen on x-ray may be confused for a bone infection. A bone infection is very unlikely if the skin is intact and there is no ulcer present.