Foramen Magnum Orientation and Its Association with Cervical Lordosis: A Model for Reconstructing Cervical Curvature in Archeological and Extinct Hominin Specimens
The
cranial base is located at a critical intersection between the vertebral spine,
the brain, the respiratory system and the mastication apparatus. Therefore it
can provide an insight into the evolution of the head and neck in functional
and phylogenetic contexts. However, the relationship between cranial base
anatomy and cervical spine alignment has not been explored deeply. Therefore
the aim of this research is to study the relationship between the orientation
of the foramen magnum and the degree of cervical lordosis. Based on this
relationship we developed six models which enable reconstruction of the
cervical lordosis angle in archeological material and in extinct hominins. 74
adult lateral cervical radiographs were examined. The orientation of the
foramen magnum and the angle of the cervical lordosis were measured on each
radiograph. Foramen magnum orientation positively correlates with cervical
lordosis angles: moderate to high correlation was found between foramen magnum
orientation and the total cervical lordosis (0.716 < r < 0.612); moderate
correlation was also found between foramen magnum orientation and the upper
cervical lordosis (0.626 < r < 0.562); and only weak correlation was
found with the lower cervical lordosis (0.306 < r < 0.101). Assuming that
the positive correlation between foramen magnum orientation and cervical
lordosis can be applied to all bipedal hominins, cranial base morphology can
provide an insight to the degree of the cervical lordosis of archeological
material and of extinct hominin.
References
[1]
Aiello, L., & Dean, C. (1990) An Introduction to Human Evolutionary Anatomy. Waltham: Academic Press, Harcourt Brace and Co.
[2]
Ashton, E. H., & Zuckerman, S. (1956) Age Changes in the Position of the Foramen Magnum in Hominids. Proceedings of the Zoological Society of London, 126, 315-325. http://dx.doi.org/10.1111/j.1096-3642.1956.tb00440.x
[3]
Barbera, A. L., Sampson, W. J., & Townsend, G. C. (2009) An Evaluation of Head Position and Craniofacial Reference Line Variation. Homo, 60, 1-28. http://dx.doi.org/10.1016/j.jchb.2008.05.003
[4]
Bench, R. W. (1963) Growth of the Cervical Vertebrae as Related to Tongue, Face, and Denture Behavior. American Journal of Orthodontics, 49, 183-214. http://dx.doi.org/10.1016/0002-9416(63)90050-2
[5]
Broom, R. (1938) The Pleistocene Anthropoid Apes of South Africa. Nature, 142, 377-379. http://dx.doi.org/10.1038/142377a0
[6]
Chan, C. A. (2007) A Review of the Clinical Significance of the Occlusal Plane: Its Variation and Effect on Head Posture. International College of Craniomandibular Orthopedics (ICCMO) Anthology, 8, 1-63.
[7]
Dart, R. (1925) Australopithecus Africanus: The Man-Ape of South Africa. Nature, 115, 195-199. http://dx.doi.org/10.1038/115195a0
[8]
Dean, M. C., & Wood, B. A. (1981) Metrical Analysis of the Basicranium of Extant Hominoids and Australopithecus. American Journal of Physical Anthropology, 54, 63-71. http://dx.doi.org/10.1002/ajpa.1330540109
[9]
Dean, M. C., & Wood, B. A. (1982) Basicranial Anatomy of Plio-Pleistocene Hominids from East and South Africa. American Journal of Physical Anthropology, 59, 157-174. http://dx.doi.org/10.1002/ajpa.1330590206
[10]
Festa, F., Tecco, S., Dolci, M. et al. (2003) Relationship between Cervical Lordosis and Facial Morphology in Caucasian Women with Skeletal Class II Malocclusion: A Cross-Sectional Study. Journal of Craniomandibular Practice, 21, 121-129.
[11]
Filler, A. G. (2007). Emergence and Optimization of Upright Posture among Hominiform Hominoids and the Evolutionary Pathophysiology of Back Pain. Neurosurgical Focus, 23, 1-6.
[12]
Hardacker, J. W., Shuford, R. F., Capicotto, P. N., & Pryor, P. W. (1997). Radiographic Standing Cervical Segmental Alignment in Adult Volunteers without Neck Symptoms. Spine, 22, 1472-1479. http://dx.doi.org/10.1097/00007632-199707010-00009
[13]
Hellsing, E., Forsberg, C. M., Linder-Aronson, S., & Sheikholeslam, A. (1986). Changes in Postural EMG Activity in the Neck and Masticatory Muscles Following Obstructions of the Nasal Airways. European Journal of Orthodontics, 8, 247-253. http://dx.doi.org/10.1093/ejo/8.4.247
[14]
Kimbel, W. H., & Rak, Y. (2010). The Cranial Base of Australopithecus afarensis: New Insights from the Female Skull. Philosophical Transactions of the Royal Society B: Biological Sciences, 365, 3365-3376. http://dx.doi.org/10.1098/rstb.2010.0070
[15]
Le Gros Clark, W. E. (1954). Reason and Fallacy in the Study of Fossil Man. Advanced Science of London, 43, 1-13.
[16]
Linder-Aronson, S. (1979). The Growth in the Sagittal Depth of the Bony Nasopharynx in Relation to Some Other Facial Variables. In J. A. McNamara (Ed.), Naso-Respiratory Function and Craniofacial Growth, Monograph 9, Craniofacial Growth Series (2nd ed., pp. 27-40). Ann Arbor: Center for Human Growth and Development, University of Michigan.
[17]
Luboga, S. A., & Wood, B. A. (1990). Position and Orientation of the Foramen Magnum in Higher Primates. American Journal of Physical Anthropology, 81, 67-76. http://dx.doi.org/10.1002/ajpa.1330810108
[18]
Madsen, D. P., Sampson, W. J., & Townsend, G. C. (2008). Craniofacial Reference Plane Variation and Natural Head Position. European Journal of Orthodontics, 30, 532-540. http://dx.doi.org/10.1093/ejo/cjn031
[19]
Masters, A. V., Falk, D., & Gage, T. B. (1991). Effects of Age and Gender on the Location and Orientation of the Foramen Magnum in Rhesus Macaques (Macaca mulatta). American Journal of Physical Anthropology, 86, 75-80. http://dx.doi.org/10.1002/ajpa.1330860106
[20]
Moore, W. J., Adams, L. M., & Lavelle, C. L. B. (1973). Head Posture in the Hominoidea. Journal of Zoology, 169, 409-416. http://dx.doi.org/10.1111/j.1469-7998.1973.tb03120.x
[21]
Ozbek, M. M., & Koklü, A. (1993). Natural Cervical Inclination and Craniofacial Structure. American Journal of Orthodontics and Dentofacial Orthopedics, 104, 584-591. http://dx.doi.org/10.1016/S0889-5406(05)80442-1
[22]
Russo, G. A., & Kirk, E. C. (2013). Foramen Magnum Position in Bipedal Mammals. Journal of Human Evolution, 65, 656-670. http://dx.doi.org/10.1016/j.jhevol.2013.07.007
[23]
Schaefer, M. S. (1999). Foramen Magnum-Carotid Foramina Relationship: Is It Useful for Species Designation? American Journal of Physical Anthropology, 110, 467-471. http://dx.doi.org/10.1002/(SICI)1096-8644(199912)110:4<467::AID-AJPA7>3.0.CO;2-R
[24]
Solow, B., Siersbæk-Nielsen, S., & Greve, E. (1984). Airway Adequacy, Head Posture and Craniofacial Morphology. American Journal of Orthodontics, 86, 214-223. http://dx.doi.org/10.1016/0002-9416(84)90373-7
[25]
Solow, B., & Sandham, A. (2002). Cranio-Cervical Posture: A Factor in the Development and Function of the Dentofacial Structures. European Journal of Orthodontics, 24, 447-456. http://dx.doi.org/10.1093/ejo/24.5.447
[26]
Schultz, A. H. (1961). Vertebral Column and Thorax. In H. Hofer, A. H. Schultz, & D. Stark (Eds.), Primatologia (Vol. 4, pp. 1-46). Basel: Karger.
[27]
Tecco, S., & Festa, F. (2007). Cervical Spine Curvature and Craniofacial Morphology in an Adult Caucasian Group: A Multiple Regression Analysis. European Journal of Orthodontics, 29, 204-209. http://dx.doi.org/10.1093/ejo/cjl061
[28]
Vig, P. S., Showfety, K., & Phillips, C. (1980). Experimental Manipulation of Head Posture. American Journal of Orthodontics, 77, 258-268. http://dx.doi.org/10.1016/0002-9416(80)90081-0
