Rheumatoid Arthritis of the Hand

Rheumatoid arthritis is a condition which involves the synovium of the joints. It occurs more often in females than males. There may be a hereditary component with rheumatoid arthritis. Rheumatoid arthritis is characterized by spontaneous remissions and exacerbations as well as pain and stiffness of joints, especially in the morning (morning stiffness). This disease can have a systemic nature. Rheumatoid arthritis is typically poly-articular, bilateral, and symmetrical — most commonly affecting the hands and feet.

An x-ray will show periarticular erosions at the time of diagnosis. Osteopenia and minimal osteophyte formation favors the diagnosis of rheumatoid arthritis. Rheumatoid is an autoimmune disease with two important components — immunological reactions and increased degradative enzymes.

The IgM (rheumatoid factor) is produced by the plasma cell as an antibody to the native IgG, which is altered in RA. 70% of the patients with RA will have a positive rheumatoid factor. Leucocytes are attracted to the immune complex forming deposits over the inflammatory surface of the synovium. These leukocytes ingest fibrin and immune complex and is called the rheumatoid cells. The leukocytes release lysosomal enzymes that cause acute inflammatory response and tissue necrosis as well as inflammatory mediators (IL-1, IL-6, TNFα). The chondrocytes respond to stimulation by TNFα, IL-1 and other inflammatory mediators causing cells to become activated and secrete more metaloproteinases which lead to cartilage damage. The synovium becomes hypertrophied (pannus), showing intimal hyperplasis and infiltration by plasma cells and lymphocytes.

Stages of Rheumatoid Arthritis:

Early (Acute): hot, swollen, tender joints (synovitis) — swelling is commonly seen at the MCP, wrist, and flexor sheath. More complicated symptoms include — digital vasculitis, ecchymosis, skin atrophy, and nodules.

Advanced Stage: Swelling of the MCP joints, lateral slippage of extensor tendons and tendon ruptures. You will find ulnar deviation of fingers. X-rays will show destruction of MCP with subluxation, ulnar deviation, and wrist destruction.

The thumb is also involved. These changes occur due to proliferation, inflammation, and hypertrophy of the synovium. Involvement of the distal radioulnar joint is usually associated with rupture of the extensor digiti minimi.

25% of patients with RA will have subcutaneous nodules on extensor surfaces of the elbow and forearm. Nodules are often multiple and seen along the ulnar margin of the forearm or pulp of the digits. Vasculitis is more common in patients with S.C. nodules, it is a strongly seropositive disease (aggressive) with a less than favorable prognosis. Treatment for synovitis typically consists of a splint and medical treatment. If there is narrowing of the joint space, bone erosions, or osteopenia, the physician may perform a synovectomy. For patient’s experiencing joint destruction, fixed deformity, or a loss of hand function, there will be surgery based on condition.

Prior to operating on patients with Rheumatoid Arthritis, an x-ray of the cervical spine is needed because the patient may have subluxation of C1-C2. Metacarpophalangeal joint arthroplasty of the fingers usually results in decreased extensor lag and improvement of the ulnar drift.