What does pterygium cause in nails?

• A. Distorted nail growth due to skin adherence to the nail plate, often from severe injury or infection
• B. A fungal infection causing discoloration
• C. Normal aging
• D. A genetic variant with stronger nails

Answer: (A)

Pterygium of the nail causes distortion in growth because skin from the surrounding nail folds adheres to and scars the nail plate. This adhesion pulls on the developing nail as it grows, producing a permanently deformed edge and irregular nail shape. It usually follows severe trauma, infection, burns, or inflammatory skin conditions that damage the nail matrix and surrounding tissue. So the nail grows with a distorted, often fixed, band where the skin has fused to the nail plate. It’s not caused by a fungal infection, normal aging, or a genetic variant affecting nail strength.