skin disorders
Fingernail and Toenail Injury
Onychotillomania
People with this disorder Body-Focused Repetitive Behavior Disorder . The most common manifestation is the habit-tic deformity, in which the person frequently picks at or rubs the central cuticle (the skin at the base of the nail) with a neighboring finger. This manifestation is most often seen on the thumbnail and leads to a washboard-like appearance in the center of the nail plate. Onychotillomania can also cause bleeding beneath the nails (subungual hemorrhage), infection in the nail unit, and even complete loss of the nail plate. 