In rheumatoid arthritis, the lining of the joint that becomes inflamed is known as the ...?

In rheumatoid arthritis, the lining of the joint that becomes inflamed is known as the ...?

• A. Endosteum
• B. Periosteum
• C. Synovium
• D. Articular cartilage

Answer: (C)

In rheumatoid arthritis, the tissue most involved is the synovium—the lining of the joint capsule that normally produces lubricating fluid. When RA affects this lining, it becomes inflamed (synovitis), thickens, and can form proliferative tissue called pannus that invades and damages cartilage and bone. This makes the synovium the correct term for the inflamed joint lining. Endosteum lines the inner surface of bone, not the joint cavity. Periosteum covers the outer surface of bone. Articular cartilage is the smooth tissue covering the ends of bones in a joint, not the lining of the joint cavity.

In rheumatoid arthritis, the tissue most involved is the synovium—the lining of the joint capsule that normally produces lubricating fluid. When RA affects this lining, it becomes inflamed (synovitis), thickens, and can form proliferative tissue called pannus that invades and damages cartilage and bone. This makes the synovium the correct term for the inflamed joint lining.

Endosteum lines the inner surface of bone, not the joint cavity. Periosteum covers the outer surface of bone. Articular cartilage is the smooth tissue covering the ends of bones in a joint, not the lining of the joint cavity.