Anatomy and Cell Biology

Korean Association of Anatomists (대한해부학회)
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Atlanto-occipital assimilation: embryological basis and its clinical significance

  • Hari Hara Hanusun N (Department of Anatomy, All India Institute of Medical Sciences) ;
  • Akanksha Singh (Department of Anatomy, All India Institute of Medical Sciences) ;
  • Pooja Poddar (Department of Anatomy, All India Institute of Medical Sciences) ;
  • Jessy J P (Department of Anatomy, All India Institute of Medical Sciences) ;
  • Neerja Rani (Department of Anatomy, All India Institute of Medical Sciences) ;
  • Hitesh Gurjar (Department of Neurosurgery, All India Institute of Medical Sciences) ;
  • Seema Singh (Department of Anatomy, All India Institute of Medical Sciences)
  • Received : 2023.08.29
  • Accepted : 2023.10.30
  • Published : 2024.03.31
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Abstract

Atlanto-occipital assimilation is an osseous embryological anomaly of the craniovertebral junction in which the atlas (C1) is fused to the occiput of skull. Embryologically, this assimilation may happen due to failure of the segmentation and separation of the caudal occipital and the cranial cervical sclerotome. The segmentation clock is maintained by NOTCH and WNT signalling pathways along with Hox genes and retinoic acid. This condition is likely to be a consequence of mutation in above mentioned genes. The knowledge of this assimilation may be crucial for the clinicians as it may lead to various neurovascular symptoms. The present case report involves the analysis of atlanto-occipital assimilation with its clinical significance and embryological basis.

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References

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