Embryology, Classification, and Surgical Management of Bony Malformations of the Craniovertebral Junction

  • Dachling PangEmail author
  • Dominic N. P. Thompson
Part of the Advances and Technical Standards in Neurosurgery book series (NEUROSURGERY, volume 40)


The embryology of the bony craniovertebral junction (CVJ) is reviewed with the purpose of explaining the genesis and unusual configurations of the numerous congenital malformations in this region. Functionally, the bony CVJ can be divided into a central pillar consisting of the basiocciput and dental pivot; and a two-tiered ring revolving round the central pivot, comprising the foramen magnum rim and occipital condyles above, and the atlantal ring below. Embryologically, the central pillar and the surrounding rings descend from different primordia, and accordingly, developmental anomalies at the CVJ can also be segregated into those affecting the central pillar and the surrounding rings, respectively. A logical classification of this seemingly unwieldy group of malformations is thus possible based on their ontogenetic lineage, morbid anatomy, and clinical relevance. Representative examples of the main constituents of this classification scheme are given, and their surgical treatments are selectively discussed.


Congenital malformation Craniovertebral junction Genetic control Hox genes Instability Neural compression Occipital-cervical fusion Primary somitogenesis Sclerotomal resegmentation 


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© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.Department of Paediatric NeurosurgeryUniversity of CaliforniaDavisUSA
  2. 2.Department of Paediatric NeurosurgeryRegional Centre of Pediatric Neurosurgery, Kaiser Foundation Hospitals of Northern CaliforniaOaklandUSA
  3. 3.Department of Paediatric NeurosurgeryKaiser Permanente Medical CenterOaklandUSA
  4. 4.Department of Paediatric NeurosurgeryGreat Ormond Street Hospital for Children NHS TrustLondonUK

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