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Retronychia is an uncommonly reported condition among the category of nail pathologies. It often presents mimicking similar nail disorders, such as onychocryptosis, onychomycosis, and paronychia. This pathologic condition has recently seen an increased presence in the literature, mainly in the form of case studies. Literature on retronychia was collected using PubMed, the US National Library of Medicine, the National Institutes of Health's online database, life science journals, and online books. References cited by these articles were also reviewed for additional relevant publications. Reviews, case studies, and retrospective articles were compiled and analyzed for commonalities in cause, patient demographics, clinical signs, and treatment. Retronychia may be more common than previously suggested. Proper knowledge and education of this pathologic nail condition is important to health-care professionals to achieve early and correct diagnosis.
California School of Podiatric Medicine at Samuel Merritt University, Oakland, CA.