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J Neurol Surg A Cent Eur Neurosurg
DOI: 10.1055/a-1962-0181
Original Article

The Internal Trabecular Bone Structure of the Odontoid Process of the Axis. A Retrospective Single-Center Comparative Study in Patients Following Cervical Trauma

Nicola Montemurro 
1   Department of Neurosurgery, Azienda Ospedaliera Universitaria Pisana (AOUP), Pisa, Italy
2   Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
,
Ardico Cocciaro
1   Department of Neurosurgery, Azienda Ospedaliera Universitaria Pisana (AOUP), Pisa, Italy
,
Gaetano Liberti
1   Department of Neurosurgery, Azienda Ospedaliera Universitaria Pisana (AOUP), Pisa, Italy
,
Mirco Cosottini
2   Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
,
Paolo Perrini
1   Department of Neurosurgery, Azienda Ospedaliera Universitaria Pisana (AOUP), Pisa, Italy
2   Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
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Abstract

Background Odontoid C2 fractures account for 9 to 15% of adult cervical spine fractures. The aim of this study is to report the incidence of a previously described Y-shaped trabecular bone structure (TBS) in the odontoid process in a larger sample of patients with a computed tomography (CT) scan following a cervical trauma to investigate if its absence can increase the risk of odontoid process fracture of the axis.

Methods A retrospective review of 245 patients who underwent a CT scan for cervical spine injury was performed during a 12-month period between May 2020 and May 2021.

Results The presence of a Y-shaped TBS at the odontocentral synchondrosis level was observed in 165 patients (67.3%) included in this study. Eighteen patients (7.3%) had an odontoid type II C2 fracture. A Y-shaped TBS at the odontocentral synchondrosis level was observed in 8 (44.4%) of these 18 patients. The presence of a Y-shaped TBS at the odontocentral synchondrosis level was statistically more frequently observed in patients without an odontoid process fracture (69.2 vs. 30.8%) compared with patients who developed an odontoid process fracture (44.4 vs. 55.6%) after a cervical trauma (p = 0.03).

Conclusions This study highlights the crucial role of the Y-shaped TBS in the biomechanics of the C1–C2 joint and its significant clinical relevance in odontoid fractures of the axis.

Keywords

odontoid process - cervical anatomy - axis - biomechanics - computed tomography scan


Publication History

Received: 08 August 2022

Accepted: 14 October 2022

Accepted Manuscript online:
17 October 2022

Article published online:
09 June 2025

© 2025. Thieme. All rights reserved.

Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany

 

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