Cho SY, et al. - Authors ascertained the demographics of ingrown nail (IN) and clarify its correlation with bone-related comorbidities of the ankle, foot and toe. They compared the patients in a representative sample cohort of the National Health Information Database of South Korea from 2004 to 2013 who had IN with a control group without IN. Females demonstrated increasing tendencies of IN incidence and prevalence. Findings suggested an association of confirmed bone deformity, especially acquired valgus or varus deformity, and flat foot with IN.