Review of onychocryptosis: epidemiology, pathogenesis, risk factors, diagnosis and treatment.

Ingrown toenail, or onychocryptosis, is a highly prevalent nail condition that occurs when the nail edge grows into the periungual dermis. It most frequently affects the hallux and has a biphasic presentation, being most common in the second and fifth decades. It is often painful and may be debilitating in severe cases. Risk factors include trauma, weight changes, poor nail-cutting technique, and hyperhidrosis. Both conservative and surgical treatments have been described, and choice of therapy is dependent on patient co-morbidities, severity, and associated symptoms. This review covers the epidemiology, risks factors, pathogenesis, evaluation, and staging of ingrown toenails, as well as, treatment options. Although there is an unmet need for clinical trials comparing therapies, current recommendations are to treat conservatively and then proceed to surgical therapies if symptoms persist.