リリース：Microsoft RSAT for Windows 7 SP1（20110412-1）

Trachyonychia, also known as twenty-nail dystrophy, was an uncommon condition characterized by nail fragility, excessive longitudinal growth, ridging, and loss of luster. It was often idiopathic but could be associated with dermatoses like alopecia areata, lichen planus, and psoriasis. A reported case involved a young male with trachyonychia and concurrent cutaneous lichen planus, reticular oral lichen planus, and nail lichen planus, diagnosed through dermoscopy and histopathology. Proper diagnosis was crucial for treating the underlying cause, as early intervention improved prognosis and alleviated psychological and cosmetic concerns.