Dermatology (Beau's Lines) and Forensic Pathology (Harris Lines and Linear Enamel Hypoplasia) Signs of Growth Arrest: A Case Report and Literature Review

Abstract

Dermatology encompasses the evaluation and management of localized conditions that affect the nail plate, including trauma, primary dermatoses involving the nail bed and nail matrix, and systemic disorders with manifestations that impact the nail unit. In addition to traumatic events that can alter the nail unit, localized conditions such as periungual dermatitis and infections, as well as generalized diseases, can affect the nail matrix, resulting in temporary growth arrest of the nail plate. This can present as a groove (Beau's line) in the nail plate that progressively grows out as the nail continues to grow. Forensic pathology includes forensic anthropology. Disease and starvation are the most common etiologies associated with growth arrest of the long bones near the epiphyseal plate; the radiolucent horizontal bands (Harris lines) are only observable on the roentgenogram. Localized injuries, malnutrition, and childhood illnesses can result in growth arrest of enamel formation in the teeth (linear enamel hypoplasia); this condition appears as white pits, grooves, and/or bands on the crowns of permanent teeth. A 65-year-old man experienced a trauma-associated Beau's line on his left great toenail plate. He developed a subungual hematoma; approximately 10 weeks after the injury, he noted the appearance of a Beau's line. Growth arrest of the nail plate (Beau's lines), growth arrest of the long bones near the epiphyseal plate (Harris lines), and growth arrest of the teeth's enamel formation (linear enamel hypoplasia) can be caused by adverse events such as systemic illnesses, malnutrition, medication effects, and trauma. In conclusion, diagnostic stigmata of growth arrest, such as Beau's lines of the nail plate, Harris lines of the long bones, and linear enamel hypoplasia of the teeth, can be detected during the cutaneous inspection of the nails, the radiologic evaluation of the long bone, and the oral examination of the teeth.

Keywords: beau’s line; dermatology; enamel; forensic; harris; hypoplasia; linear; nail; pathology; teeth.

Figure 1. Beau’s line on the left great toenail of a 65-year-old man

Distant top view (A), closer top view (B), and closer lateral view (C) of the left great toe. Beau’s line appears as the horizontal groove (between the black and the white arrows) and extends transversely across the nail plate from the lateral nailfolds on each side of the toe. The trauma to the proximal nail fold, when a plastic container dropped onto the proximal nailfold (black triangles), was the etiology of Beau’s line; the appearance of the subungual hematoma (black discoloration of the distal nail plate) occurred prior to the presentation of Beau’s line.

Figure 2. Harris lines on the distal radius and ulna

Radiopaque Harris growth arrest lines are present on the right distal radius and ulna (demonstrated by orange arrows with black outlines) in a 13-year-old boy with an underlying bone disease. The photograph was provided on April 13, 2017, by James Heilman, MD. Permission for free republishing is granted; the file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.

Figure 3. Linear enamel hypoplasia

The teeth show white-appearing horizontal lines of linear enamel hypoplasia (demonstrated by the white arrows) on their surfaces. The enamel hypoplasia lines demonstrate the defects of enamel that form during crown development because of either nutritional stress or disease during infancy and childhood. The photograph was provided by Brian Spatola on October 22, 2007, from the Otis Historical Archives National Museum of Health & Medicine. Permission for free republishing is granted; the file is licensed under the Creative Commons Attribution 2.0 Generic license.