What is an Ingrown Toenail?

Painful ingrown toenail due to abnormal curvature of the nail, causing the formation of an abscess and local infection.

An ingrown toenail is a medical condition where the outside edge(s) of the toenail becomes embedded into the soft tissue of the toe, causing irritation, pain, hypergranulation tissue or infection. There are several causes for ingrown toenails.

Ingrown toenails are relatively common, and can affect people of any age, however they tend to have a higher incidence in active teenagers, and also the elderly.

There are several well known causes for ingrown toenails, and sufferers may have one or more reasons why they have developed problems. The most common causes are:

• Structural issues with the shape and growth of the nail
  This is often present from birth (congenital) and means that one or more nails have become involuted or convoluted. The nail then tends to wrap into the edges of the toe and cause chronic problems.

Marked involution (curvature) of both sides of the nail, also known as a 'pincer' nail.

• Previous injury or trauma to the nail
  Any injury to the toe that damages the nail and the growth area of the nail (the matrix), can cause the nail to begin to grow in an unusual manner that can lead to the nail to be deformed, thickened or grow in an irregular direction. Once the nail has been damaged in this manner, it is unlikely to ever go back to its normal appearance.
• Poor nail cutting technique
  When the nail is cut too aggressively into the corners or down the side, it is possible to either leave an irregular edge to the toenail, or even have a small piece of nail come away and become stuck into the side of the toe causing a foreign body reaction (or granuloma). Leaving the nail slightly longer, cutting along the natural curve of the nail, and not cutting down the side of the toenail can prevent this occurring.
• Age
  The culmination of years of wearing enclosed footwear, and repeated small knocks and bumps to toes and toenails can cause the toenail to gradually become deformed and have irregular growth.
• Other toe and foot problems
  If you suffer from hammertoes, bunions, very high arched feet and many other conditions, the position of the toe (and toenail) can be altered from its most ideal alignment. This may cause the toenail to be frequently in direct contact with the ground, or in an unusual position which puts pressure of the soft tissues and the nail bed. Over time this can also cause the nail to become deformed or altered.

In some situations, ingrown toenails can become very severe, and cause a marked about of overgrowth of skin along the edge of the nail. This is known as hypergranulation tissue, and is caused by constant irritation of the skin by the pressure from the nail.

Severe ingrown toenail, with hypergranulation tissue growing over both sides of the nail.