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Updated: Jan 23, 2026

A Spine Robotic-Assisted Navigation System for Pedicle Screw Placement
Published on: May 11, 2020
[Dorsal stabilization of C1/C2 modified according to Goel-Harms with C1 pedicle screws]
Lennart Viezens1, Stephan Sehmisch2, Lukas Weiser2
1Klinik für Unfallchirurgie, Orthopädie und Plastische Chirurgie, Universitätsmedizin Göttingen (Direktor: Prof. W. Lehmann), Robert-Koch-Straße 40, 37075, Göttingen, Deutschland. lennart.viezens@med.uni-goettingen.de.
Objective:
Stabilization of the atlantoaxial transition by an alternative screw position in C1.
Indications:
Instabilities C1/C2 due to inflammation, tumor or trauma.
Contraindications:
Presence of a very small pedicle of C1. Variations in the course of the vertebral arteries.
Surgical Technique:
The midline approach to the upper cervical spine is used for the modified instrumentation of C1 with pedicle screws instead of Harms screws and for the unaltered instrumentation of C2. Depending on the indication, dorsal spondylodesis is performed by opening the laminae and attaching ceramic bone substitute material.
Postoperative Management:
In mobile patients, additional immobilisation with a soft collar is recommended for 6 weeks. Full recovery is given 3-4 months after surgery.
Results:
From January 2017 to September 2018, 21 stabilizations of the atlantoaxial transition were performed. The mean age was 72.52 ± 15.45 years. A total of 42 screws were placed in C1. In all, 21 (50%) C1 pedicle screwscould be placed, and in other 21 cases Harms screws were used. Complications were seen in 3 patients. Overall, considering the contraindications, the instrumentation of C1 with pedicle screws appears as a safe alternative to instrumentation with Harms screws.
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