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The Value of Foramen Magnum Diameters for Gender Identification Among Iranian Population

Siamak Soltani, Kamran Aghakhani, Hanieh Saboori-Shekofte, Sahar Rismantab-Sani, Forouzan Faress, Tayebe Khayamdar




Background: By assessing the size of the foramen magnum, it is possible to distinguish two genders, as well as the intergenerational interdependence of the affected individuals. The present study aimed at assessing the value of diameters of foramen magnum for gender identification among the Iranian population.
Methods: This analytical comparative cross-sectional study was performed on 200 Iranian cadavers (100 men and 100 women) referred to Kahrizak Autopsy Hall in Tehran between 2017 and 2018. In each case, the foramen magnum was measured by observation and its parameters were measured in a longitudinal anteroposterior and transverse diameter, using a calibrated caliper.
Results: The Mean±SD anterior-posterior diameter of the foramen magnum in men and women were 35.59±0.49 mm and 33.90±1.07 mm, respectively, which was significantly higher in men (P<0.001). Similarly, the Mean±SD transverse diameter of the foramen magnum in males and females was 29.49±0.56 mm and 28.5±0.50 mm, respectively, which was significantly higher in men (P<0.001). Based on the area analysis under the Receiver Operating Characteristic (ROC) curve, the anterior-posterior and transverse diameters of the foramen magnum had a high value in the differentiation of the male and female genders (AUC=0.953 and 0.896, respectively, P<0.001). The Mean±SD foramen magnum index in men and women was 84.15±3.02 and 82.87±1.95, respectively, which had a significant difference between the two genders.
Conclusion: Given that the anterior-posterior and transverse diameters of the foramen magnum in Iranian men are far more than Iranian women, these diameters can be used to distinguish between the two genders in the precise legal field.


Foramen magnum, Gender identification, Iranian population


‎1.‎ Uthman AT, Al-Rawi NH, Al-Timimi JF. Evaluation of foramen magnum in gender determination using helical CT scanning. ‎Dentomaxillofacial Radiology. 2012; 41(3):197-202. [DOI:10.1259/dmfr/21276789]‎

‎2.‎ Günay Y, Altinkök M. The value of the size of foramen magnum in sex determination. Journal of Clinical Forensic Medicine. 2000; ‎‎7(3):147-9. [DOI:10.1054/jcfm.2000.0430] [PMID]‎

‎3.‎ Krishan K, Chatterjee PM, Kanchan T, Kaur S, Baryah N, Singh RK. A review of sex estimation techniques during examination of ‎skeletal remains in forensic anthropology casework. Forensic Science International. 2016; 261:165-e1-e8. ‎‎[DOI:10.1016/j.forsciint.2016.02.007] [PMID]‎

‎4.‎ Aghakhani K, Kazemzadeh N, Ghafurian F, Soltani B, Soltani S. Gender determination using diagnostic values of foramen ‎magnum. International Journal of Medical Toxicology and Forensic Medicine. 2016; 6(1):29-35. ‎‎[DOI:10.22037/ijmtfm.v6i1(Winter).9503]‎

‎5.‎ Poonamjeet L, Ongeti K, Pulei A, Ogengo J, Mandela P. Gender related patterns in the shape and dimensions of the foramen ‎magnum in an adult Kenyan population. Anatomy Journal of Africa. 2013; 2(2):138-41.‎

‎6.‎ Kanodia G, Parihar V, Yadav YR, Bhatele PR, Sharma D. Morphometric analysis of posterior fossa and foramen magnum. Journal ‎of Neurosciences in Rural Practice. 2012; 3(3):261-6. [DOI:10.4103/0976-3147.102602] [PMID] [PMCID]‎

‎7.‎ Standarding S. Gray’s anatomy: The anatomical basis of clinical practice. London: Elsevier Churchill Livingstone; 2005.‎

‎8.‎ Kanchan T, Gupta A, Krishan K. Craniometric analysis of foramen magnum for estimation of sex. International Journal of Medical, ‎Health, Biomedical and Pharmaceutical Engineering. 2013; 7(7):111-3.‎

‎9.‎ Suazo Galdames IC, Perez Russo P, Zavando Matamala DA, Smith RL. Sexual dimorphism in the foramen magnum dimensions. ‎International Journal of Morphology. 2009; 27(1):21-3. [DOI:10.4067/S0717-95022009000100003]‎

‎10.‎ Edwards K, Viner MD, Schweitzer W, Thali MJ. Sex determination from the foramen magnum. Journal of Forensic Radiology and ‎Imaging. 2013; 1(4):186-92. [DOI:10.1016/j.jofri.2013.06.004]‎

‎11.‎ Manoel CC, Prado FB, Caria PH, Groppo FC. Morphometric analysis of the foramen magnum in human skulls of Brazilian ‎individuals: Its relation to gender. Brazilian Journal for Morphological Sciences. 2009; 26(2):104- 8.‎

‎12.‎ Shepur MP, Magi M, Nanjundappa B, Havaldar PP, Gogi P, Saheb SH. Morphometric analysis of foramen magnum. International ‎Journal of Anatomy and Research. 2014; 2:249-55.‎

‎13.‎ Holland TD. Sex determination of fragmentary crania by analysis of the cranial base. American Journal of Physical Anthropology. ‎‎1986; 70(2):203-8. [DOI:10.1002/ajpa.1330700207] [PMID]‎

‎14.‎ Graw M. [Morphometrische und morphognostische Geschlechtsdiagnostik an der menschlichen Schadelbasis (German)]. ‎Osteologische Identifikation und Altersschatzung. 2001:103-21.‎

‎15.‎ Barut NR, Kale AN, Turan Suslu HK, Ozturk A, Bozbuga M, Sahinoglu K. Evaluation of the bony landmarks in transcondylar ‎approach. British Journal of Neurosurgery. 2009; 23(3):276-81. [DOI:10.1080/02688690902814725] [PMID]‎

‎16.‎ Furtado SV, Thakre DJ, Venkatesh PK, Reddy K, Hegde AS. Morphometric analysis of foramen magnum dimensions and ‎intracranial volume in pediatric Chiari I malformation. Acta Neurochirurgica. 2010; 152(2):221-7. [DOI:10.1007/s00701-009-0480-‎‎5] [PMID]‎

‎17.‎ Howale DS, Bathija A, Gupta S, Pandit DP. Correlation between cranial index and foramen magnum index in human dried skulls. ‎Global Journal For Research Analysis. 2014; 3(1):3-6. [DOI:10.15373/22778160/January2014/65]‎

‎18.‎ Kumar A, Dave M, Anwar S. Morphometric evaluation of foramen magnum in dry human skulls. International Journal of Anatomy ‎and Research. 2015; 3(2):1015-23. [DOI:10.5137/1019-5149.JTN.4297-11.1] [PMID]‎

‎19.‎ Singh PK, Tamrakar D, Karki S, Menezes RG. Determination of sex from the foramen magnum using 3DCT: A nepalese study. ‎Kathmandu University Medical Journal. 2017; 15(57):62-6.‎

‎20.‎ Tellioglu AM1, Durum Y, Gok M, Karakas S, Polat AG, Karaman CZ. Suitability of foramen magnum measurements in sex determination and their ‎clinical significance. Folia Morphologica. 2018; 77(1):99-104. [DOI:10.5603/FM.a2017.0070] [PMID]‎

‎21.‎ Madadin M, Menezes RG, Al Saif HS, Alola HA, Al Muhanna A, Gullenpet AH, et al. Morphometric evaluation of the foramen ‎magnum for sex determination: A study from Saudi Arabia. Journal of Forensic and Legal Medicine. 2017; 46:66-71. ‎‎[DOI:10.1016/j.jflm.2017.01.001] [PMID]‎

‎22.‎ Kamath VG, Asif M, Shetty R, Avadhani R. Binary logistic regression analysis of foramen magnum dimensions for sex determination. Anatomy Research ‎International. 2015; 2015(459428):1-9. [DOI:10.1155/2015/459428] [PMID] [PMCID]‎

DOI: https://doi.org/10.32598/ijmtfm.v9i4.25367