A cross-sectional study of morphometric variations of the foramen magnum in adult human skulls.
DOI:
https://doi.org/10.51168/sjhrafrica.v7i3.2568Keywords:
foramen magnum, morphometry, skull, craniovertebral junction, anatomyAbstract
Background:
The foramen magnum is a key osteological landmark at the craniovertebral junction and shows population-specific variation in size and shape with clinical, anthropological, and forensic relevance.
Objectives:
To assess the morphometric dimensions, morphological patterns, and foramen magnum index in adult human skulls from a teaching institution in Telangana.
Methods:
This cross-sectional osteological study was conducted on fifty intact adult dry human skulls. The anteroposterior diameter, transverse diameter, and foramen magnum area were recorded using standard morphometric methods. Shape was assessed by gross observation, and the foramen magnum index was categorized as dolichotrematous, mesotrematous, or brachytrematous. Data were summarized using mean, standard deviation, frequency, and percentage.
Results:
The mean anteroposterior diameter was 32.8 ± 2.3 mm, and the mean transverse diameter was 27.4 ± 2.1 mm. The calculated mean area was 710.6 ± 92.4 mm². Oval was the commonest shape, observed in 40.0% of skulls, followed by round in 22.0% and hexagonal in 14.0%. Based on index assessment, 62.0% of skulls were dolichotrematous, 24.0% were mesotrematous, and 14.0% were brachytrematous.
Conclusion:
Adult skulls demonstrated appreciable variation in foramen magnum dimensions and shape, with predominance of oval morphology and elongated index pattern. These findings provide baseline regional morphometric data relevant to craniovertebral surgical orientation, anatomical teaching, and comparative osteological studies.
Recommendations:
Morphometric assessment of the foramen magnum should be incorporated into anatomical databases and surgical training, and larger multicentric studies should be undertaken to establish region-specific reference standards.
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