Triangular worn-down nails: Report of 14 cases

The aim of this paper is to report how the nails can be worn out by a repetitive rubbing against a surface. In the last 13 years we have observed 14 patients with similar nail abnormalities affecting several fingernails. The nails presented a triangular area of marked thinning that extended from the middle nail plate to the distal margin, which showed a wedge-shaped incision. All patients were in good health. Six of them were taylors and referred to rub the nails against cloth while sewing. One other patient had the habit of rubbing the fingernails against the anterior surface of the tight when nervous. They were instructed to cut their nail short, to avoid the rubbing habit and to apply a 10% urea containing ointment and to take oral biotin 5 mg/ daily. Evaluation after 6 months revealed improvement of the nail abnormalities in 9 patients and complete cure in 5. The follow-up revealed complete cure of all patients. Recurrences were observed in 3 patients. Triangular worn down nails represent a new variety of brittle nails which can be occupational or self-induced. The improvement of onychodystrophy after cutting the nails short and after paying them attention proofs the importance of a mechanical trauma. However, although environmental factors usually precipitate nail lesions, the fact that this type of nail brittleness does not occur in all subjects exposed to these noxae indicates an individual intrinsic susceptibility to nail plate damage.