Morphometry of the C2 pedicle and lamina in thai patients

 

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Background: Traumatic upper cervical spine leads to instability and neurological deficit. At present, C2 (axis) pedicle or lamina screws for fixation are popular because further external immobilization is not needed. However, these techniques demand experience inserting the screws and carry the risk of vertebral artery or spinal cord injury. In some patients, the C2 screws cannot be inserted because of limited C2 size. Objective: To determine the width, length, height, and angle in the C2 pedicle and lamina in the Thai population. Materials and Methods: Patient data were collected from the Picture Archiving and Communication System at the Faculty of Medicine, Prince of Songkla University from January 2016 to December 2017. The C2 parameters, i.e., width, length, height, and angle of the pedicle and lamina were recorded. Results: The CT C-spine scans of 270 patients were enrolled. The mean Thai C2 pedicle dimensions were width 5.51 mm, length 23.78 mm, angle 39.04°, and height 8.64 mm. The mean C2 lamina dimensions were width 5.88 mm, length 32.17 mm, angle 49.46°, and height 12.27 mm. Twenty-four patients from the 270 patients (8.8%) had a pedicle width <3.5 mm but all patients had a lamina width ≥3.5 mm. Conclusion: In the Thai samples, 8.8% had a C2 pedicle width <3.5 mm which would not allow insertion of screws; however, they could be replaced with lamina screws since the lamina width was ≥3.5 mm. In this study, all of the patients who could not be inserted pedicle can be replaced with lamina screws inserted.

Financial support and sponsorship

Nil.

Publication History

Received: 18 October 2019

Accepted: 13 November 2019

Article published online:
16 August 2022

© 2020. Asian Congress of Neurological Surgeons. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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• References

• 1 Cassinelli EH, Lee M, Skalak A, Ahn NU, Wright NM. Anatomic considerations for the placement of C2 laminar screws. Spine (Phila Pa 1976) 2006;31:2767-71.
• 2 Jeanneret B, Magerl F. Primary posterior fusion C1/2 in odontoid fractures: Indications, technique, and results of transarticular screw fixation. J Spinal Disord 1992;5:464-75.
• 3 Grob D, Jeanneret B, Aebi M, Markwalder TM. Atlanto-axial fusion with transarticular screw fixation. J Bone Joint Surg Br 1991;73:972-6.
• 4 Elliott RE, Tanweer O, Boah A, Morsi A, Ma T, Frempong-Boadu A, et al. Atlantoaxial fusion with transarticular screws: Meta-analysis and review of the literature. World Neurosurg 2013;80:627-41.
• 5 Harms J, Melcher RP. Posterior C1-C2 fusion with polyaxial screw and rod fixation. Spine (Phila Pa 1976) 2001;26:2467-71.
• 6 Elliott RE, Tanweer O, Boah A, Morsi A, Ma T, Frempong-Boadu A, et al. Outcome comparison of atlantoaxial fusion with transarticular screws and screw-rod constructs: Meta-analysis and review of literature. J Spinal Disord Tech 2014;27:11-28.
• 7 Wajanavisit W, Lertudomphonwanit T, Fuangfa P, Chanplakorn P, Kraiwattanapong C, Jaovisidha S. Prevalence of high-riding vertebral artery and morphometry of C2 pedicles using a novel computed tomography reconstruction technique. Asian Spine J 2016;10:1141-8.
• 8 Parker SL, McGirt MJ, Garcés-Ambrossi GL, Mehta VA, Sciubba DM, Witham TF, et al. Translaminar versus pedicle screw fixation of C2: Comparison of surgical morbidity and accuracy of 313 consecutive screws. Neurosurgery 2009;64:343-8.
• 9 Bunmaprasert T, Treenarong N, Khamkhad A. Appropriate size and angulation for axis screw placement. J Med Assoc Thai 2015;98:188-95.
• 10 Liu J, Napolitano JT, Ebraheim NA. Systematic review of cervical pedicle dimensions and projections. Spine (Phila Pa 1976) 2010;35:E1373-80.
• 11 Yusof MI, Ming LK, Abdullah MS. Computed tomographic measurement of cervical pedicles for transpedicular fixation in a Malay population. J Orthop Surg (Hong Kong) 2007;15:187-90.
• 12 Kim YJ, Rhee WT, Lee SB, You SH, Lee SY. Computerized tomographic measurements of morphometric parameters of the C2 for the feasibility of laminar screw fixation in Korean population. J Korean Neurosurg Soc 2008;44:15-8.
• 13 Ma XY, Yin QS, Wu ZH, Xia H, Riew KD, Liu JF. C2 anatomy and dimensions relative to translaminar screw placement in an Asian population. Spine (Phila Pa 1976) 2010;35:704-8.