Arthritis of the wrist

1. What are two different kinds of arthritis that affect the wrist?
2. What is seen clinically in Rheumatoid arthritis?
3. What is a swan-neck deformity?
4. What is Boutonniere's deformity?
5. What is seen clinically in osteoarthritis?
6. Where is wrist osteoarthritis most common?

Answers:
1. Rheumatoid arthritis (autoimmune attack on synovial tissue, which destroys the articular cartilage and leads to bone destruction) and osteoarthritis (deterioration of articular cartilage and formation of new bone at joint margins).
2. Swelling of the wrists, MCP and PIP, ulnar deviation of the wrist, dorsal subluxation of the ulna, erosion of the ulnar styloid.
3. Contracture of hand intrinsics, resulting in MCP flexion, PIP hyperextension, DIP flexion.
4. Tearing of the extensor hood, resulting in MCP hyperextension, PIP flexion, and DIP hyperextension.
5. Heberden's (DIP) and Bouchard's (PIP) nodules, tenderness along the area of involvement and crepitus of the wrist, cyst formation in the joint space.
6. First CMC joint.