Image-based drill templates for cervical pedicle screw placement
- 1 January 2009
- journal article
- Published by Journal of Neurosurgery Publishing Group (JNSPG) in Journal of Neurosurgery: Spine
- Vol. 10 (1), 21-26
- https://doi.org/10.3171/2008.9.spi08229
Abstract
Pedicle screws (PSs) in the cervical spine can provide fixation superior to current fixation methods; however, their implementation is challenging due to the small size of the cervical vertebrae. In this study, the authors explored and evaluated the use of patient-specific, rapid prototype drill templates for PS placement in the cervical spine. The goal of the study was to assess the accuracy of a drill template in the placement of cervical PSs at a single vertebral level. Volumetric CT scanning was performed in 4 cadaveric cervical spines. Using computer software, the authors constructed drill templates with a predefined trajectory designed to match the posterior surface of vertebrae C3–7. Twenty physical templates were created from the computer models using a rapid prototyping machine. The drill templates were used to guide pilot-hole drilling, and CT scanning was performed to assess the accuracy of the pilot holes. Pedicle screws (3.5-mm diameter) were placed in the pilot holes. The spines were then dissected to separate the vertebrae, and the trajectory of the screws was visually inspected. The feasibility of this patient-specific, rapid prototyping technique was demonstrated. Imaging and visual inspection of pilot holes and cervical PSs revealed that the majority of trajectories did not violate the pedicle cortex (19 [95%] of 20). The single cortical violation was judged as noncritical and would probably not have resulted in injury to a patient. The potential of drill templates to aid in the placement of cervical PSs is promising. The authors' methods appear to provide an accurate technique and trajectory for PS placement in the cervical spine.Keywords
This publication has 39 references indexed in Scilit:
- Percutaneous Placement of Posterior Cervical Screws Using Three-Dimensional FluoroscopySpine, 2006
- Biomodeling as an Aid to Spinal InstrumentationSpine, 2005
- Personalised image-based templates for intra-operative guidanceProceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine, 2005
- Biomechanical evaluation of cervical lateral mass fixation: a comparison of the Roy-Camille and Magerl screw techniquesJournal of Neurosurgery: Spine, 2004
- Three-Dimensional Computed Tomography-Based, Personalized Drill Guide for Posterior Cervical Stabilization at C1–C2Spine, 2001
- Complications of Pedicle Screw Fixation in Reconstructive Surgery of the Cervical SpineSpine, 2000
- Indirect posterior reduction and fusion of the traumatic herniated disc by using a cervical pedicle screw systemJournal of Neurosurgery: Spine, 2000
- Correction of Cervical Kyphosis Using Pedicle Screw Fixation SystemsSpine, 1999
- One-stage posterior decompression and reconstruction of the cervical spine by using pedicle screw fixation systemsJournal of Neurosurgery: Spine, 1999
- Morphometric Evaluation of Lower Cervical Pedicle and Its ProjectionSpine, 1997