Rheumatoid arthritis or RA is an autoimmune disorder in which immune cells erroneously attack the tissues lining the joints. According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), approximately 1.3 million adults in the United States have RA. Long-standing RA can cause joint deformities, progressive loss of function, and chronic pain. Although RA can affect any joint, some are more frequently affected than others.
Wrists
"The Merck Manual for Healthcare Professionals" reports the wrists are commonly involved in RA. A defining characteristic of RA compared to other types of arthritis is its symmetrical distribution, meaning the effects on one side of the body mirror the other. Hence, most people with RA have the disease in both wrists.
Hand and Finger Joints
The Arthritis Foundation advises RA frequently affects the hand and finger joints. The joints at the base of the fingers, the metacarpophalangeal joints or MCPs, often become swollen and painful. The MCPs of the first two fingers prove particularly vulnerable to RA. The joints above the MCPs, the proximal interphalangeal joints or PIPs, are also frequently affected with RA. The effects of RA on the MCPs and PIPs can severely limit use of the hands. Tasks of everyday living such as writing, turning a doorknob, opening a jar or twist cap or buttoning clothing can become increasingly difficult. Interestingly, RA characteristically spares the finger joints below the fingernails, the distal interphalangeal joints or DIPs. This feature of RA helps distinguish it from osteoarthritis, which often involves the DIPs.
Shoulders and Elbows
RA may affect the shoulder and elbow joints. The American Academy of Orthopaedic Surgeons explains that damage to the joints and surrounding ligaments and tendons may cause deformities, which limit joint movement. Additionally, the muscles around involved joints often wither from lack of use causing progressive muscle weakness. The combined effects of these abnormalities precipitate wide-ranging challenges in daily living. Lifting, grooming the hair, reaching overhead and countless other tasks may become exceedingly difficult for someone with RA in the shoulders and elbows.
Ankles, Feet and Toes
RA can affect the many joints of the ankles, feet and toes. Involvement of these joints causes mild to severe walking difficulties and instability with an increased risk for falls. Hammertoes and bunions can develop, advises the American Academy of Orthopaedic Surgeons. With severe RA disease of the ankles, joint fusion or arthrodesis may become necessary. This involves removing the diseased cartilage and affixing the bones to eliminate movement of the affected joint. Although mobility of the joint is lost, pain is relieved and the overall stability of the ankle improved.
References
- National Institute of Arthritis and Musculoskeletal and Skin Diseases: Rheumatoid Arthritis
- American Academy of Orthopaedic Surgeons: Rheumatoid Arthritis
- Arthritis Foundation: Rheumatoid Arthritis, What are the Effects?
- Merck Manual for Healthcare Professionals: Rheumatoid Arthritis, Signs and Symptoms
- American College of Rheumatology: Rheumatoid Arthritis
