Pathology of Heberden’s Nodes
Heberden’s nodes are bony enlargements that develop on the distal interphalangeal (DIP) joints, the joints closest to the fingertips. They are a common sign of osteoarthritis, a degenerative joint disease.
Pathology:
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Cartilage Breakdown:
- Wear and Tear: Over time, the protective cartilage in the joints, especially the DIP joints, begins to wear down.
- Loss of Cushioning: As the cartilage thins, the bones in the joint rub against each other, causing pain, stiffness, and inflammation.
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Bone Spur Formation:
- Body’s Repair Response: The body attempts to repair the damaged joint by forming bony growths, or bone spurs.
- Enlarged Joints: These bone spurs can enlarge the joint, leading to the visible appearance of Heberden’s nodes.
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Joint Inflammation:
- Synovitis: The synovium, the tissue lining the joint, can become inflamed.
- Swelling and Pain: This inflammation can cause swelling, redness, and pain in the affected joints.
Contributing Factors:
- Age: The risk of developing Heberden’s nodes increases with age.
- Genetics: A family history of osteoarthritis can increase susceptibility.
- Joint Injury: Previous injuries to the hands can accelerate joint degeneration.
- Repetitive Stress: Frequent use of the hands, especially in manual labor or certain hobbies, can contribute to the development of Heberden’s nodes.