Causes of ingrown toenails

Ingrown toenails are a common nail problem, usually seen in young adults. Typically, the lateral side or corner of the toenail digs into the skin at the end or side of the great toe, but ingrown toenails can also occur on both sides of the toe or on any toenail. The cause often includes anatomical and environmental factors.

Anatomical predispositions to ingrown toenails are:

• congenital malalignment of the nail
• hereditary overcurvature of the nail
• imbalance between the width of the nail matrix and the nail bed.

Environmental factors include excessive or convex cutting of the nail (cutting into the corners to achieve a curved nail), wearing of pointed-toe and high-heeled shoes, onychomycosis (tinea of the nails), repeated trauma (eg sports, running), and oral retinoids.