Rheumatoid Arthritis: What is it?

RA is an immune disorder termed seropositive. This means in many patients with RA the rheumatoid factor (M class) can be identified in their blood (serum). Not everyone with who tests positive for the rheumatoid factor develops the disease. Researchers indicate the disease cannot be inherited but the susceptibility toward development could be, although this has not been proven. The actual cause is unknown.

Joints are lined in a membrane called the synovium. In rheumatoid arthritis, the white blood cells, whose normal duty is to provide immunity, turn against the synovial membrane causing inflammation. In turn, inflammation triggers the release of chemicals causing the synovial membrane to thicken. Destructive enzymes in the synovial fluid create a granulated membrane (pannus) that covers the normal joint surface. Over time, these chemicals and enzymes can destroy joint cartilage, bone, tendons, and ligaments. As these structures are compromised, the joint loses it shape and alignment.

In the spine, RA usually affects the cervical spine. The joints in the upper cervical spine include the odontoid process, a tooth-like structure that rises from the body of the axis (second cervical vertebra). The odontoid moves anteriorly (front) with the atlas (first cervical vertebra). The joint space between the axis and the atlas is termed atlantoaxial.

The lower cervical spine includes the lateral (side) joints termed zygapophyseal or facet joints.

Rarely is the thoracic or lumbar spine involved. The patient's symptoms may include headache, neck pain, paresthesias, weakness in the arms and legs, and paraparesis. The disease can also cause joint swelling, pain, stiffness, loss of joint motion and muscle strength, fatigue, loss of appetite, fever, and difficulty sleeping.