Sex Estimation From Histomorphometric Analysis of Cortical Bone: A Hospital-based Study

Abstract

Estimation of the sex of unknown skeletal remains is a daunting challenge, when only fragmented bones are available. For this reason, there is a need to study population specific histomorphometric features of bones to provide useful data for the process of identification. The purpose of this study was to estimate sex from six histomorphometric parameters of cortical bones in a cohort of Nigerian patients. The samples comprised non-pathologic bones collected from 29 patients (12 females and 17 males) between the ages of 35 to 85 years during orthopaedic procedures. The modified Frost’s manual method was used to prepare the histological sections of the cortical bones. The parameters evaluated were number of primary osteons (Os-p), number of secondary osteons (Os-s), osteon fragments (Os-f), non-Haversian canal (N-Hc), area of Haversian canal (Area Hc), and Haversian canal diameter (HCD). The data obtained were analyzed using SPSS version 23.0. Tests for sex differences were done using student t-test and stepwise discriminant function was used to formulate a predictive model for sex estimation. The mean Os-p, Os-s, Os-f, N-hc, Area HC, and HCD were 2.85 ± 0.86,3.92 ± 1.26,6.08 ± 1.37, 2.23 ± 0.66, 53.43 ± 5.55, and 7.85 ± 0.41 for males and 1.11 ± 0.56, 0.33 ± 0.17, 2.44 ± 0.67, 54.37 ± 6.04 and 7.426 ± 0.35 for females, respectively. The mean value of Os-s was significantly different in males and females (p=0.04). Stepwise discriminant function analysis showed Os-s could be used to estimate sex. 71.4% of our samples were correctly predicted based on sex. Discriminant function values of 0.418 and -0.626 were predictive values for males and females, respectively, using the DFA predictive model. Our study shows that the number of secondary osteons (Os-s) could be used to estimate sex in Nigerian patients.