Ingrown nail
Onychocryptosis (from Greek ὄνυξ onyx "nail" + κρυπτός kryptos "hidden"), also known as an ingrown toenail, or unguis incarnatus is a common form of nail disease. It is an often painful condition in which the nail grows so that it cuts into one or both sides of the paronychium or nail bed. This condition has been found only in shoe-wearing cultures and does not occur in habitually barefoot people since it requires downward pressure on the nail by a shoe.
The common opinion is that the nail enters inside the paronychium but an ingrown toenail may be overgrown toe skin. The condition starts from a microbial inflammation of the paronychium, secondary to a granuloma, and the result is a nail buried inside the granuloma. While ingrown nails can occur in the nails of both the hands and the feet, they occur most commonly with the toenails.
A true ingrowing toenail, or onychocryptosis, is caused by the actual penetration of the flesh by a sliver of nail.
Signs and symptoms
Symptoms of an ingrown nail include pain along the margins of the nail (caused by hypergranulation that occurs around the aforementioned margins), worsening of pain when wearing tight footwear, and sensitivity to pressure of any kind, even the weight of bedsheets. Bumping of an affected toe can produce sharp, even excruciating, pain as the tissue is punctured further by the nail. By the very nature of the condition, ingrown nails become easily infected unless special care is taken to treat the condition early on and keep the area clean. Signs of infection include redness and swelling of the area around the nail, drainage of pus, and watery discharge tinged with blood. The main symptom is swelling at the base of the nail on the side the nail is ingrowing (may be both sides).
