Where is subchondral bone located, and how does it change in osteoarthritis?

Where is subchondral bone located, and how does it change in osteoarthritis?

• A. It is the bone beneath the articular cartilage, and it becomes denser and sclerotic in osteoarthritis
• B. It is the bone at the center of the bone
• C. It disappears in OA
• D. It is the outer cortical bone

Answer: (A)

Subchondral bone is the bone directly beneath the articular cartilage, providing the foundation for joint surfaces. In osteoarthritis, this area often responds to abnormal joint loading by becoming denser and thicker—a process called sclerosis. This increased density reflects adaptive remodeling of the bone under the stressed cartilage. It’s not the bone at the center of the bone (the medullary cavity) or the outer cortical shell, and it doesn’t disappear in OA; instead it undergoes characteristic structural changes, sometimes with accompanying subchondral cysts or osteophyte formation.

Subchondral bone is the bone directly beneath the articular cartilage, providing the foundation for joint surfaces. In osteoarthritis, this area often responds to abnormal joint loading by becoming denser and thicker—a process called sclerosis. This increased density reflects adaptive remodeling of the bone under the stressed cartilage. It’s not the bone at the center of the bone (the medullary cavity) or the outer cortical shell, and it doesn’t disappear in OA; instead it undergoes characteristic structural changes, sometimes with accompanying subchondral cysts or osteophyte formation.