Sexual Dimorphism in Cranial and Post-Cranial Skeletal Elements: Forensic Implications for Sex Estimation in a Contemporary Thai Population

Napakorn Sangchay; Kavin  Tangmanpakdeepong; Saidontree  Boonyarud; Sujinthara  Wansopha; Natipong  Chatthai; Patara  Rattanachet; Jirapa  Chetsawang

doi:10.33192/smj.v77i11.277229

Authors

Napakorn Sangchay Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Kavin Tangmanpakdeepong Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Mahidol University International College, Mahidol University, Nakhon Pathom, Thailand
Saidontree Boonyarud Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Mahidol University International College, Mahidol University, Nakhon Pathom, Thailand
Sujinthara Wansopha Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Mahidol University International College, Mahidol University, Nakhon Pathom, Thailand
Natipong Chatthai Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; College of Medical Science, Western University, Bangkok, Thailand
Patara Rattanachet Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Jirapa Chetsawang Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand

DOI:

https://doi.org/10.33192/smj.v77i11.277229

Keywords:

Sexual dimorphism, cranial and post-cranial skeletal elements, forensic implications for sex estimation, contemporary Thai population

Abstract

Objective: The analysis of human skeletal remains is instrumental in forensic and anthropological contexts, particularly for establishing biological profiles of unidentified individuals. Determining sex via skeletal examination is a fundamental component of this process and traditionally involves morphological assessment and metric analysis of pelvic and cranial bones. Nevertheless, the precision and reliability of these methodologies—whether through morphological evaluation or morphometric analysis—remain subjects of ongoing debate and scrutiny. This research set forth to investigate the efficacy of morphological and morphometric analysis in sex estimation by focusing on cranial and post-cranial long bones within contemporary Thai population.

Materials and Methods: The study sample comprised 204 skulls (105 from males, and 99 from females) and 200 sets of long bones of upper (humerus, radius, and ulna) and lower extremities (femur and tibia). Multiple measurements were systematically obtained from various anatomical regions of each bone, and measurements of extremity long bones were compared between the left and right sides.

Results: The analysis revealed statistically significant differences in these metrics between sexes, indicating the potential utility of this approach for sex classification. However, despite achieving high levels of accuracy, the studied methodology yielded some classification errors, which suggests some potential limitations.

Conclusion: The findings suggest that both inherent skeletal variability in cranial and post-cranial morphology within contemporary Thai population and the specific analytical techniques employed can markedly influence the accuracy of sex determination. These factors harbor and confer important implications for forensic and anthropological applications.

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