Os Odontoideum Syndrome: Pathogenesis, Clinical Patterns and Indication for Surgical Strategies in Childhood

  • Massimiliano VisocchiEmail author
  • Concezio Di Rocco
Part of the Advances and Technical Standards in Neurosurgery book series (NEUROSURGERY, volume 40)


Os odontoideum is a rare condition with a controversial pathogenesis and poorly understood natural history. Hypoplasia of the odontoid associated with an independent oval ossicle, with smooth margins widely separated from C2 and well above the superior facets of the axis, is termed “os odontoideum”. The neurological manifestations arise from bulbospinal compression both at rest and during motion, due to the craniovertebral junction (CVJ) instability itself. Consequently, the surgical management of os odontoideum should aim at achieving both neural decompression and stabilization of the CVJ. The aims of this paper are to introduce the embryological steps involved in the CVJ development, to underline the updated theories propounded to interpret developmental and congenital disorders of the os odontoideum, to introduce the most updated surgical techniques and to discuss some exemplary cases selected from our personal experience.


Os odontoideum Craniovertebral junction Transoral Transnasal Transcervical endoscopic approach Wiring/screwing instrumentation and fusion 


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.Department of Head Neck DiseasesInstitute of Neurosurgery, Catholic University of RomeRomeItaly

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