Matthew J Zdilla1,2,3, Kelsey R Mangus4, Jordan V Swearingen5, Kyle D Miller5, H Wayne Lambert5. 1. Department of Natural Sciences and Mathematics, West Liberty University, CSC 139, P.O. Box 295, West Liberty, WV, 26074, USA. mzdilla@westliberty.edu. 2. Department of Graduate Health Sciences, West Liberty University, West Liberty, WV, USA. mzdilla@westliberty.edu. 3. Department of Pathology, Anatomy, and Laboratory Medicine (PALM), Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, WV, USA. mzdilla@westliberty.edu. 4. Department of Natural Sciences and Mathematics, West Liberty University, CSC 139, P.O. Box 295, West Liberty, WV, 26074, USA. 5. Department of Pathology, Anatomy, and Laboratory Medicine (PALM), Robert C. Byrd Health Sciences Center, West Virginia University School of Medicine, Morgantown, WV, USA.
Abstract
PURPOSE: Submental anatomical variation is of clinical importance with regard to head and neck surgeries. One such anatomical variation is that of additional musculature joining the intermediate tendon of the digastric muscle to the midline of the mylohyoid musculature-a variation which this report refers to, accordingly, as an arrowhead variation. Though the arrowhead variation has been described in several case reports, it has not been subject to cross-sectional study. The purpose of this study is to determine the prevalence of the arrowhead variation. METHODS: Prevalence of the arrowhead variation was assessed in 19 cadavers via gross dissection. RESULTS: Two of the 19 cadavers (10.5%) were found to have arrowhead variations. The arrowhead variation was found in one male (1:11; 9.1%) and one female (1:8; 12.5%), respectively. CONCLUSIONS: This report demonstrates that the submental arrowhead variation of the anterior digastric and mylohyoid musculature has been reported in isolated case reports since the nineteenth century. This report is the first cross-sectional study of the arrowhead variant, identifying it in approximately one in ten individuals and in both sexes. Therefore, the presence of an arrowhead variation should be regularly considered with regard to diagnosis of submental masses. Likewise, the arrowhead variation should be considered in the preoperative planning of the myriad operations performed in the submental region.
PURPOSE: Submental anatomical variation is of clinical importance with regard to head and neck surgeries. One such anatomical variation is that of additional musculature joining the intermediate tendon of the digastric muscle to the midline of the mylohyoid musculature-a variation which this report refers to, accordingly, as an arrowhead variation. Though the arrowhead variation has been described in several case reports, it has not been subject to cross-sectional study. The purpose of this study is to determine the prevalence of the arrowhead variation. METHODS: Prevalence of the arrowhead variation was assessed in 19 cadavers via gross dissection. RESULTS: Two of the 19 cadavers (10.5%) were found to have arrowhead variations. The arrowhead variation was found in one male (1:11; 9.1%) and one female (1:8; 12.5%), respectively. CONCLUSIONS: This report demonstrates that the submental arrowhead variation of the anterior digastric and mylohyoid musculature has been reported in isolated case reports since the nineteenth century. This report is the first cross-sectional study of the arrowhead variant, identifying it in approximately one in ten individuals and in both sexes. Therefore, the presence of an arrowhead variation should be regularly considered with regard to diagnosis of submental masses. Likewise, the arrowhead variation should be considered in the preoperative planning of the myriad operations performed in the submental region.
Authors: Matthew J Zdilla; Jordan V Swearingen; Kyle D Miller; Adam Bender-Heine; H Wayne Lambert Journal: J Craniofac Surg Date: 2017-03 Impact factor: 1.046