Median nail dystrophy
Median nail dystrophy (also known as "Dystrophia unguis mediana canaliformis," "Median canaliform dystrophy of Heller,": 657  and "Solenonychia") consists of longitudinal splitting or canal formation in the midline of the nail, a split which often resembles a fir tree, occurring at the cuticle and proceeding outward as the nail grows.: 788 Thumbs, which are the most commonly involved, usually show an enlarged lunula resulting probably from repeated pressure applied on the base of the nail.: 657

See also
Nail (anatomy)
Habit-tic deformity


== References ==