Acquired ectopic nail: A case report in an 18-year-old female with traumatic onset

Post-traumatic ectopic nail (PTEN) refers to the abnormal growth of a new nail in a site other than the usual one, typically occurs after a trauma to the nail matrix. The exact pathogenesis is still unknown. This rare condition often affects the dorsal aspect of the phalanx. Surgical excision of the nail is the treatment of choice, with complete destruction of the nail matrix.

We report a case of an 18-year-old female presenting to the clinic with an asymptomatic keratotic lesion on the lateral aspect of the distal phalanx after 3 years of digit trauma. X-ray imaging of the affected finger was normal, without any bony deformity. The ectopic nail was surgically excised with cauterization of the matrix to prevent relapse.

Ectopic nails can be either congenital or acquired. Injuries can lead to PTEN formation by causing the germinal matrix to divide and implant into the skin. The ectopic nail in our case arises from the lateral aspect of the finger 3 years after trauma, which is an unusual occurrence.

The ectopic nail causes an aesthetical concern, usually with no other symptoms. However, surgical excision is necessary, with emphasis on the importance of cauterizing the matrix to prevent future relapse.