Ingrown toenail, or onychocryptosis, is a commonly encountered problem in family practice. Patients usually present with pain in the affected nail but with progression, drainage, infection, and difficulty walking occur. Most patients present with ingrown toenail during the second and third decades of life, but teenagers often develop ingrown toenails after tearing the corners of their toenails.

Possible causes of ingrown toenails include improperly trimmed nails, hyperhidrosis, poorly fitting footwear, trauma, subungual neoplasms, obesity, or excessive external pressure. These alterations cause the nail to improperly fit into the lateral nail groove, producing edema and inflammation of the lateral nail fold.

Stage 1 ingrown toenails are characterized by erythema, slight edema, and pain with pressure to the lateral nail fold. Stage 2 is marked by increased symptoms, drainage, and infection. Stage 3 ingrown toenails display magnified symptoms, granulation tissue, and lateral nail-fold hypertrophy.

Many physicians advocate conservative management for stage 1 ingrown toenails, including warm soaks, cotton-wick elevation of the affected nail corner, or antibiotic therapy in the presence of infection (Table 1). Simple, partial nail avulsion has been tried for stage 2 nails but is successful in eradicating the condition in only 30 percent of patients. Stage 3 ingrown toenails can develop from a laterally pointing spicule of nail beneath the nail fold. Excision of the lateral nail plate combined with lateral matricectomy is believed to provide the best chance for eradication. In the treatment of stage 3 toenails, the associated granulation tissue and lateral wall hypertrophy also should be removed.
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