Morphometric Study of Unusual Foramina of The Sphenoid Bone Unusual foramina of the Sphenoid bone
International Clinical Neuroscience Journal,
Vol. 11 No. 1 (2024),
4 November 2025
,
Page e9
https://doi.org/10.22037/icnj.v11i1.42879
Abstract
Background: The Pterygospinous and the Pterygoalar foramina are rare anatomical structures on the skull's base near the sphenoid bone. These structures have clinical significance as landmarks in medical and surgical procedures. Understanding the anatomy and incidence of ossified ligaments associated with these foramina is crucial for neurosurgical, dental, and maxillofacial procedures. The present study was undertaken to assess the incidence, structural details and clinical importance of formation of unusual foramina of sphenoid bone in the skulls of Indian population.
Methods: The present observational study was conducted on 200 dry skulls and disconnected sphenoid bones. Direct cranioscopy and digital caliper measurements were used to assess the pterygospinous and pterygoalar foramina, ossification, and location of ligaments. The observed data were statistically analyzed using SPSS 22 software.
Results: Complete ossification of the pterygospinous foramen was observed bilaterally in 1% of bones, with incomplete ossification in 5.5% of bones. In the pterygoalar foramen, complete ossification was found in 2% of cases on the left and 1% on the right sides. Incomplete ossification was observed in 1% on the left side, 2.5% on the right side, and 1.5% bilaterally. The measurements of both foramina indicated that the Pterygospinous foramen had a larger diameter than the Pterygoalar foramen.
Conclusion: The incidence of ossified pterygospinous and pterygoalar ligaments and their foramina formation in the skulls of the Indian population is low. Understanding the prevalence and anatomy of these structures is crucial for medical professionals to diagnose and treat neurological and maxillofacial conditions.
- Pterygospinous foramen; Pterygoalar foramen; Sphenoid bone; Ossification; Anatomical landmark; Neurosurgical procedures; Maxillofacial surgeries
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References
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