INTERMASTOID DISTANCE OF THE HUMAN SKULL: PATTERNS OF INDIVIDUAL VARIABILITY

Abstract

Sexual dimorphism of the mastoid processes of the temporal bones, namely their linear dimensions, size and shape, and the distance between them, are used in research aimed at determining the gender of the skulls. The distance between the mastoid processes is measured either as intermastoidale distance, or as the intermastoid lateral surface distance, IMLSD. Both indicators aff ect the determination of the sex of skulls better than linear dimensions. At the same time, in previous studies of gender diff erences in the intermastoid distance, the relationships between intermastoid distance and morphometric indicators characterizing the size of the skull were not taken into account. The purpose of the study: to establish the patterns of individual variability of the intermastoid lateral surface distance, namely, its relationship with the variability of the width of the skull base, the distance between asterions and the width of the cerebral cranium (transverse diameter of the skull). The study was conducted on 50 skulls (33 male and 17 female) from the craniological collection of the Department of Human Anatomy of KhNM U.It was established that the intermastoid lateral surface distance in men is signifi cantly greater than in women (M±: 127,4±5,6 and 118,5±3,5, respectively; p<0,05). This is explained by the larger size of the male skull compared to the female one and the peculiarities of the somatotypes of male and female organisms. In men, there are statistical relationships between the intermastoid lateral surface distance, on the one hand, and the width of the skull base (y=0.6x+56.5; r=0.6), the distance between asterions (y=0.5x+67.3; r=0.6), the transverse diameter of the skull (y=0.4x+72.3; r=0.4), on the other hand, are noticeable and statistically signifi cant (p<0.05), while in women they are much smaller (respectively, y=0.3x+87.6; r=0.3; y=0.3x+84.9; r=0.2; p<0.05; and y=0.4x+61.6; r=0.3, p>0.05). The shape of the skull does not aff ect the distance between the mastoid processes, both in men and in women.