Type of Article:  Original Research

Volume 5; Issue 2.1 (April 2017)

Page No.: 3682-3686

DOI: https://dx.doi.org/10.16965/ijar.2017.139


Sampada P K 1, Poornima B *2, Mallikarjun M 3, Santosh B Sakri 4.

*1,2 Assistant professor, Department of Anatomy, Vijayanagar Institute of Medical Sciences, Ballari, Karnataka, India.

3 Professor and HOD, Department of Anatomy, Vijayanagar Institute of Medical Sciences, Ballari, Karnataka, India.

4 Professor, Department of public health Dentistry, SAIDS, Calicut, Kerala, India.

Address for the Correspondence:  Dr. Poornima B, Assistant professor, Department of Anatomy, Vijayanagar Institute of Medical Sciences, Ballari, Karnataka, India. E-Mail: pnima73@gmail.com


Background: The foramen magnum is the large opening located in the occipital bone of skull. The morphometric evaluation of foramen magnum is clinically interesting because of its relation with its contents. The vital structures passing through it may endure compression such as in cases of foramen magnum herniation, foramen magnum meningiomas and foramen magnum achondroplasia. The knowledge of foramen magnum diameters is needed to determine some malformations such as Arnold Chiari syndrome, which shows expansion of transverse diameter.

Objective: To measure the anteroposterior diameter, transverse diameter and to calculate the  area of foramen magnum. The shape of the foramen was noted and were classified as oval, round, egg, tetragonal, pentagonal, hexagonal, irregular.

Materials and Methods: Completely ossified 100 dried human skull bones of unknown age and gender were taken from the Department of Anatomy, V.I.M.S., Ballari, Karnataka, India.

Results: The mean antero-posterior diameter was 34.84±2.32mm. The mean transverse diameter was 29.39±1.73mm. The mean area of foramen magnum was 803.8±83.42mm2. The foramen magnum shapes were determined as an Oval 58%, Round 9(9%), Egg 11(11%), Tetragonal 8(8%), Pentagonal 1(1%), Hexagonal(3%), irregular(10%).

Conclusion: This study will be useful for the anatomist, neurosurgeon, radiologist and orthopaedic surgeon.

KEYWORDS: Foramen Magnum, Occipital Bone, Herniations, Meningiomas, Achondroplasia.


Background: Lumber spinal canal stenosis is common spinal disorder in elderly patients causing low back pain. Ligamentum Flavum (LF) covers most of the postero-lateral part of spinal canal, hypertrophy of which considered an important causative factor in development of lumbar spinal canal stenosis which significantly contributes to low back pain and sciatica.

Materials and Methods: To measure the thickness of LF in in lumbar region at L1-L2, L2-L3, L3-L4, L4-L5, L5-S1 level on MRI a cross sectional MRI study of lumbar spine was carried out between the age group of 20-50 yrs in IPGMER and SSKM hospital, Kolkata. The study population comprised of two groups with a total 120 population of which first group comprised of patients with low back pain (LBP) (n=60), second group was control groups, persons without low back pain (n=60). T1 weighted magnetic resonance images of lumbar segments were taken and thickness of LF was measured on both right and left side in all lumbar segments.

Results: The mean thickness of LF in lumbar segment in LBP group was 3.47mm which was significantly thicker than control group measuring 2.63 mm.

Conclusion:  Patients with low back pain had significantly thicker LF in lumbar segments when compared to asymptomatic persons in both the sides which may be a contributing factor for LBP.

Key words: Ligamenta flava, Lumbar spine, Low back pain.


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Cite this article: Sampada P K, Poornima B, Mallikarjun M, Santosh B Sakri. MORPHOMETRIC AND MORPHOLOGICAL STUDY OF FORAMEN MAGNUM IN DRIED HUMAN SKULL BONES. Int J Anat Res 2017;5(2.1):3682-3686. DOI: 10.16965/ijar.2017.139