Onychophagia: detailed clinical characteristics

Abstract

Background: Onychophagia is a common disorder affecting 20% to 30% of the general population. It is defined as habitual nail biting and can cause various changes in the nail units. However, to date, there has been a paucity of data focusing on nail deformities related to onychophagia. This study was performed to investigate the clinical characteristics of onychophagia in Korea.

Methods: This study included 53 patients with onychophagia who visited the Pusan National University Hospital (Busan and Yangsan) over a 10-year period (2011-2020). We retrospectively reviewed medical records and clinical and dermoscopic photographs.

Results: All 10 fingernails were affected in 37.7% of the patients. The left thumbnail was the most predominantly affected site (81.1%). Clinical findings showed that short nails with ragged distal borders were the most common presentation (100.0%), followed by generalized or patchy rough areas (50.9%), linear and pinpoint hemorrhage (32.1%), longitudinal melanonychia (30.2%), transverse groove (28.3%), brittleness (28.3%), macrolunula (24.5%), washboard nail (13.2%), and pterygium (3.8%). Of the patients, 88.7% had periungual complications, such as periungual exfoliation (77.4%), absent or ragged cuticle (52.8%), hyponychial hyperkeratosis (37.7%), and paronychia (15.1%).

Conclusions: Although onychophagia is a common disorder, its clinical characteristics have not been reported in the literature. The results of this study may be helpful in managing patients with onychophagia.