Osteoarthritis

Question 1

What is the patho of osteoarthritis?

Answer 1

Osteoarthritis (OA) is a degenerative joint disease characterized by the progressive breakdown of articular cartilage, which leads to joint pain, stiffness, and decreased mobility. Here’s a summary of its pathology:

1. Cartilage Degradation: OA starts with the breakdown of cartilage, the smooth, cushioning tissue that covers the ends of bones in joints. Cartilage degradation results from an imbalance between cartilage synthesis and destruction.
2. Subchondral Bone Changes: As cartilage wears away, the underlying subchondral bone becomes exposed. This bone may undergo changes such as sclerosis (hardening) and the formation of bone cysts, contributing to joint pain and deformity.
3. Joint Inflammation: While OA is not primarily an inflammatory disease like rheumatoid arthritis, low-level inflammation can occur. This inflammation may involve the synovial membrane (which lines the joint capsule) and lead to swelling and pain.
4. Osteophyte Formation: The body may respond to cartilage loss by forming osteophytes, or bone spurs, around the joint margins. These growths can contribute to joint pain and restrict movement.
5. Synovial Changes: The synovial membrane may become thickened and fibrotic, further contributing to joint dysfunction and discomfort.

Overall, OA is a complex interplay of mechanical, biochemical, and inflammatory factors that lead to the progressive degeneration of joint structures.