Subungual exostosis. Histological and clinical considerations on 30 cases.

The authors review 30 cases of subungual exostosis, 27 in the foot and 3 in the hand. In approximately 80% of the cases, errors in initial diagnosis had been made, and the affection had been confused with ordinary verrucae, mycoses or pyogenic disease. Histological examination showed that in some cases the neoformation ossified by an enchondral mechanism similar to that of osteocartilaginous exostosis, while more often the mechanism was of the intramembranous or mixed type. The treatment consisted of resection of the exostosis at its base after removing the nail. Complete healing occurred in all cases.