The aim was to determine the variations in shape of the human hyoid bone in terms of symmetry, isometry and anisomorphism. These parameters are useful for surgeons and/or forensic anthropologists. Sixty-two human hyoid bones (31 male and 31 female) belonging to the Instituto Anatómico Forense (I.A.F.) of Madrid (Spain) were dissected. The data collected were analysed using the chi-square test.
The specimens were classified into five different patterns: U-shaped (16.7%), open (47.6%), triangular (9.5%), horseshoe-shaped (7.1%) and trapezoidal (19%). Types were distinguished according to the different shapes of the two halves (isomorphic 67.7% and anisomorphic 32.3%), the length of the greater horn (isometric 37% and anisometric 63%), and the transverse distances between the horns (symmetry 24.2% and asymmetry 75.8%). A thorough understanding of these anatomical variations could be useful for clinicians and forensics in interpreting the morphology of the hyoid bone.
