Stability-Sparing Endoscopic Endonasal Odontoidectomy in a Malformative Craniovertebral Junction: Case Report and Biomechanical Considerations

  • Matteo Vitali
  • Frank Rikki Canevari
  • Andrea Cattalani
  • Teresa Somma
  • Vincenzo Maria Grasso
  • Andrea Barbanera
Part of the Acta Neurochirurgica Supplement book series (NEUROCHIRURGICA, volume 125)


Background: The craniovertebral junction (CVJ) is often involved in a wide range of congenital, developmental and acquired pathologies that can create bony and ligamentous instability or cause direct compression on the medulla and cervical spine cord, resulting in significant impairment. Atlas assimilation is the most common malformation in the CVJ and can be frequently associated with basilar invagination (BI) and Chiari malformation (CM) type I. Posterior atlas assimilation more frequently leads to BI type II with a mass effect on neural structures but usually no signs of biomechanical instability. Operative approaches to the CVJ have undergone a remarkable evolution and can be divided into ventral, lateral and dorsal ones. In this kind of surgery, it is vital to detect and eventually treat any CVJ instability.

Case Description: We present a case of CVJ malformation comprising assimilation of the posterior arch of the atlas, BI type II and CM, treated by endoscopic endonasal odontoidectomy and partial clivus removal to spare CVJ stability.

Conclusion: Neurological and biomechanical analysis of all CVJ malformations permits stratification and selection of those cases that can be managed by simple, direct, minimally invasive decompression with no need for surgical fusion.


Cranio-vertebral junction Cranio-cervical malformation Atlas assimilation Basilar invagination Chiari I malformation Endoscopic endonasal odontoidectomy 





Basilar invagination


Chiari malformation


Cerebro-spinal fluid


Computed tomography


Computed tomography angiography


Craniovertebral junction




Magnetic resonance imaging


Nasopalatine line


Palatine line




Competing Interests

The authors declare that they have no competing interests.

Compliance with Ethical Standards

No financial support was received for this work.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • Matteo Vitali
    • 1
  • Frank Rikki Canevari
    • 2
  • Andrea Cattalani
    • 1
    • 3
  • Teresa Somma
    • 4
  • Vincenzo Maria Grasso
    • 1
  • Andrea Barbanera
    • 1
  1. 1.Neurosurgical Unit, Surgical DepartmentAzienda Ospedaliera SS Antonio e Biagio e Cesare ArrigoAlessandriaItaly
  2. 2.Department of OtorhinolaryngologyAzienda Ospedaliera SS Antonio e Biagio e Cesare ArrigoAlessandriaItaly
  3. 3.Neurosurgery, Department of Clinical Surgical, Diagnostic and Paediatric SciencesUniversità degli Studi di PaviaPaviaItaly
  4. 4.Division of Neurosurgery, Department of Neurosciences, Reproductive and Odontostomatological SciencesUniversità degli Studi di Napoli Federico IINaplesItaly

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