title: Vertically growing ectopic nail.
abstract: A 64-year-old Japanese woman with an ectopic nail at the palmar tip of the left middle finger is reported. Interestingly, the nail grew vertically to a line horizontal to the surface epidermis. Atypically, it appeared at 60 years of age with no prior injury or trauma to explain inoculation of a nail matrix into the regional skin. Roentgenographically, there were no abnormal findings such as Y-shaped bifurcation of the distal phalanx of the affected finger. There are conflicting opinions concerning whether or not a proximal nail fold is critical for the nail to grow outward instead of upward. Although the present case had a wide proximal nail fold, it did not seem to play its role of compressing and assisting the nail plate to grow outward. Hence, it may be that the absence of a proper nail bed, rather than the absence of a proximal nail fold, promotes upward growth of a nail plate instead of outward growth.
authors: Department of Dermatology, Otaru City General Hospital, Japan.
authors: N
authors: N
authors: Kato
mesh_terms: D002828:Choristoma / Q000473:pathology*; D005260:Female; D005385:Fingers / Q000002:abnormalities; D006801:Humans; D008875:Middle Aged; D009260:Nail Diseases / Q000175:diagnosis / Q000473:pathology; D009262:Nails