Endoscopic anterior odontoid screw fixation for the odontoid fracture: A cadaveric pilot study

Introduction: Anterior odontoid screw fixation technique for specific types of odontoid fracture has been proven to be an effective, yet challenging procedure because of threatened damage to the structures in the vicinity. There are few articles suggesting the role of percutaneous and endoscopic technique as an alternative approach to the standard microscopic way. This is the first cadaveric study using existing “EASY GO” endoscopic system-assisted odontoid screw placement. Study Design: This was a cadaveric study. Objective: The objective of the study is to use the endoscope as a safer minimally invasive approach than the standard microscopic anterior approach to odontoid. Methodology: This is a pilot study on 10 fresh-frozen formalin-fixed adult human cadavers. The cadaver was positioned in a way to simulate reduced odontoid fracture. Tubular dilators were used to dock at C2–3 disk space after identifying the landmarks through the microscopic method. The EASY GO endoscopic system was then introduced, and a handheld drill was used to mark the entry point and pass the K-wire through the planned trajectory. Results: No vascular or adjacent vital structures' injury was observed in any of the cadavers. The initial difficulty in attaining the alignment was overcome by the appropriate positioning of the scope. Conclusions: Endoscopic-assisted technique for odontoid screw fixation shall provide a minimally invasive, safe, and easy surgery.

Key-words:

Endoscopic - odontoid screw - tubular dilators

Financial support and sponsorship

Extramural Grant from AO Spine Asia Pacific.

Publication History

Received: 24 June 2020

Accepted: 24 September 2020

Article published online:
16 August 2022

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