Minimum Ischiopubic Ramus Width as a Single Metric for Sex Estimation: A Pilot Study

Robert W. Mann; Sittiporn Ruengdit; Patara Rattanachet; Napakorn Sangchay

doi:10.33192/smj.v77i12.277804

Authors

Robert W. Mann Department of Anatomy, Biochemistry, and Physiology, John A. Burns School of Medicine, The University of Hawai`i at Mānoa, Honolulu, Hawaii, USA
Sittiporn Ruengdit Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
Patara Rattanachet Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Siriraj Anatomical and Anthropological Bone Research Centre, Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Napakorn Sangchay Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand; Siriraj Anatomical and Anthropological Bone Research Centre, Department of Anatomy, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand

DOI:

https://doi.org/10.33192/smj.v77i12.277804

Keywords:

Ischiopubic ramus, sex estimation, fragmented bones, machine learning

Abstract

Objective: The present study assesses the effectiveness of the minimum width of the ischiopubic ramus as a single measurement for sex estimation.

Materials and Methods: Visual and metrical examination of 135 known-identity male and female os coxae was investigated by measuring the minimum mediolateral width of the ischiopubic ramus, a novel and simple measurement of the narrowest part of the ischiopubic ramus.

Results: The results revealed females typically have a narrow (“pinched”) ischiopubic ramus in comparison to males, with a statistically significant difference in the minimum mediolateral width of the ischiopubic ramus between sexes. Logistic regression, which delivered the best sex estimation model among traditional statistical analysis and machine learning approaches, provided an accuracy of 77.8%, a sensitivity of 83.33% and a specificity of 73.33% with a demarking point of 11.977 mm.

Conclusion: Although the method yields moderate accuracy, the minimum width of the ischiopubic ramus provides a straightforward and practical approach that may assist in sex estimation when only a fragment of the ischiopubic ramus is available. Further validation using larger and more diverse samples is recommended to confirm its applicability.

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