Pterygium of the Nail - Cutis

PTERYGIUM OF THE NAILCommentsPterygium of the nail has been described on both dorsaland ventral aspects of the nail plate. The dorsalpterygium consists of a forward growth of a projectionof the proximal nail fold that fuses with the underlyingmatrix and, subsequently, with the nail bedand divides the nail plate in 2 lateral segments. Ventralpterygium is a distal extension of the hyponychiumthat anchors to the undersurface of the nailplate and eventually obliterates the distal nail groove.Both conditions are nonspecific abnormalities of thenail apparatus.FIGURE 4. Ventral pterygium of several digits afterapplications of nail polish containing formaldehyde.or related has not been determined.PIU may be secondary to scarring in the vicinityof the distal nail groove, or it may arise from a reactionto formaldehyde-containing nail hardeners 8(Figure 4) or from subungual exostosis. PIU has beenreported once in neurofibromatosis, which was associatedwith lenticular atrophy of the palmar creasesand causalgia of the median nerve. Unilateral PIU ofthe fingers and toes has been reported 1 year after astroke and resulted in paresis of the same side.REFERENCES1. Friedman M. Nagelveranderungen bei lichen ruber. ArchDerm Syph. 1921;135:174-179.2. Zaias N. The nail in lichen planus. Arch Dermatol.1970;101:264-271.3. Edwards EA. Nail changes in functional and organic arterialdisease. New Engl J Med. 1948;239:362-365.4. Tosti A, Piraccini BM, Fanti PA, et al. Idiopathic atrophyof the nails: clinical and pathological study of two cases. Dermatology.1995;190:116-118.5. Caputo R, Prandi G. Pterygium inversum unguis. Arch Dermatol.1973;108:817-818.6. Odom RB, Stein KM, Maibach HI. Congenital, painful,aberrant hyponychium. Arch Dermatol. 1974;110:89-90.7. Mello Filho A. Ocorrencia do “pterygium inversum unguis”em populaçao adulta. Med Cut Ib Lat Am. 1985;13:401-405.8. Daly BM, Johnson M. Pterygium inversum unguis due to nailfortifier. Contact Dermatitis. 1986;15:256-257.DISCLAIMERThe opinions expressed herein are those of the authors and do not necessarily represent the views of the sponsor or its publisher. Please review complete prescribinginformation of specific drugs or combination of drugs, including indications, contraindications, warnings, and adverse effects before administering pharmacologictherapy to patients.FACULTY DISCLOSUREThe Faculty Disclosure Policy of the College of Medicine requires that faculty participating in a CME activity disclose to the audience any relationship with a pharmaceuticalor equipment company that might pose a potential, apparent, or real conflict of interest with regard to their contribution to the program.Drs. Richert, Patki, and Baran report no conflict of interest. Dr. Fisher reports no conflict of interest.346 CUTIS ®