Rheumatoid arthritis varies greatly from person to person. Learn the different ways it can progress.

Rheumatoid arthritis varies greatly from person to person, so it's hard to identify typical stages of the disease.

For a small percentage of patients, RA will persist for a year or two and then seem to become inactive. Others suffer periods of inflammation, called flares, followed by symptom-free periods, called remissions.

And in severe cases, the disease is active most of the time, persists for years, and causes serious joint damage and disability.

RA can start in any joint, but it most commonly begins in the smaller joints of the fingers, hands, and wrists. Other joints that are commonly affected include hips, knees, ankles, feet, neck, shoulders, and elbows.

Joint involvement is usually symmetrical, affecting both sides of the body equally. In addition to joint pain and inflammation, people with RA may have fatigue, occasional fevers, and a general sense of not feeling well.

How a Healthy Joint Works

To understand the progress of the disease, it's helpful to know something about the structure of a normal joint, the place where two bones meet. Inside the joint, cartilage covers the ends of the bones, cushioning them from one another.

The joint itself is lined with a thin tissue called the synovium. This tissue produces a fluid that lubricates and nourishes the cartilage and bones. This is called synovial fluid.

Under normal circumstances, a joint allows a smooth movement of bone upon bone. The cartilage provides a smooth surface and the synovial fluid provides just the right amount of lubrication for easy movements through a full range of motion.

From Healthy Joint to Joint Damage

In rheumatoid arthritis, the body's immune system attacks the cells of the synovium. This inflames the joint, making it red, warm, and painful.

During periods of inflammation, the cells of the synovium abnormally increase in number. This increased cell growth thickens the synovium, and that leads to more joint swelling.

As the disease progresses, the abnormal synovial cells invade and destroy the cartilage and bone inside the joint. Eventually, the muscles, ligaments, and tendons that support the joint weaken.

In severe cases, bones may eventually fuse together as the joint erodes away. All of this contributes to pain, loss of function and, in some cases, deformities at the affected joint.

If rheumatoid arthritis is left untreated, it can cause permanent damage to bones and tissues and cause the bones to shift out of alignment, which can make even simple tasks such as writing difficult.

Because joint damage can get worse, even when pain and swelling are relieved, it's important to treat the cause of this joint damage and not just control pain.

Doctors now believe that joint damage due to RA begins early in the disease and that treatment should begin early as well. Until recently, doctors would treat rheumatoid arthritis first with pain relievers, rest, and physical therapy and turned to more powerful drugs only if the disease worsened.

Now many doctors believe early treatment with more powerful drugs, often used in combination, may curtail the progression of rheumatoid arthritis and slow or even stop damage to the joints.

If you have symptoms of rheumatoid arthritis, it's important to see a doctor, so you can receive an accurate diagnosis and begin treatment promptly.

Close-Up of the Progression of RA Joint Damage

The joint pain and inflammation of RA begins when white blood cells (part of the immune system that cause inflammation) accumulate in the synovial tissue. The white blood cells produce substances called cytokines that transmit messages between different cells.

In healthy cells, cytokines cause inflammation in response to infection. Researchers believe that in RA several cytokines (including one called TNF, or tumor necrosis factor) may be overproduced, contributing to ongoing inflammation and destruction of cartilage, bone, and other joint tissues.

Specific Joint Problems in Untreated RA

If not treated, RA can cause significant joint damage and deformity. Some of the specific joint issues that may also occur as the disease progresses include:

Hands and wrists

• Ulnar drift: swelling of the joints, which moves tendons and ligaments out of position and causes the fingers to bend toward the little finger
• Swan-neck deformities: changes in the tissues around finger joints, which result in abnormal bending and straightening of the fingers
• Mallet finger: a deformity in which the fingertip is curled in and cannot straighten itself
• Tendon loosening or ruptures: caused by inflammation in the joints
• Movement issues: inability to bend the wrist up or down due to inflammation
• Locked or catching joints: deformities or rheumatoid nodules that cause the fingers to lock in unusual positions as the person tries to bend them

Feet

• Hammer toes: changes in the tissues around the toe joints that cause abnormal bending of the toes
• Bunions: changes in the tissues around joints of the big toe that cause it to bend toward the little toe and develop a bony nodule
• Pes planus: loosening of the arch joint in the middle of the foot, which causes a painful flat foot
• Valgus hind foot: loosening of the joint below the ankle, which causes the foot to bend outward
• Walking problems: caused by pain in the toes and other deformities

Neck

• Joint damage: limits neck movement from side to side or up and down and causes neck stiffness, weakness, and loss of motion

Shoulders

• Decreased range of motion: causes daily tasks, such as reaching or lifting, to become difficult and painful

Knees

• Inflammation: if not controlled by treatment, can cause erosion of cartilage and eventually lead to the need for knee replacement surgery
• Baker's cyst: a fluid-filled lump that appears behind the knee