Sex determination from calcification of costal cartilages in a Scottish sample

The pelvic bones and skull are not always available when human remains are discovered in a forensic setting. This study investigates the suitability to a Scottish sample of existing methods of sexing based on calcification patterns in the costal cartilages. Radiographs of chest plates of 41 cadavers, 22 male and 19 female aged 57-96 years were analyzed for their calcification patterns according to the methods of McCormick et al. (1985, Am. J. Phys. Anthropol. 68:173-195) and Rejtarova et al. (2004, Biomed. Pap. Med. Fac. Univ. Palacky. Olomouc. Czech. Repub. 148:241-243). With the method of Rejtarova et al. (2004, Biomed. Pap. Med. Fac. Univ. Palacky. Olomouc. Czech. Repub. 148:241-243) none of the male specimens was sexed correctly. Of the chest plates that were suitable for sexing, the method of McCormick et al. (1985, Am. J. Phys. Anthropol. 68:173-195) correctly sexed 82.4% of the female specimens but only 41.2% of the males. To improve the reliability, we suggest a new method of sex determination based on whether the calcified deposits in the second to seventh costal cartilages are predominantly trabecular bone or sclerotic calcified deposits. Specimens with minimal amounts or similar amounts of trabecular bone or sclerotic deposits in the costal cartilages are not appropriate for our method. When such specimens (10 specimens) were excluded, our method correctly sexed 16 of 17 (94%) males and 12 of 14 (86%) females. The authors acknowledge that their sample is small and that many of their subjects were elderly and that the method should be tested on a larger sample group before application in a forensic context.