Impact of transpedicular fixation on thoracolumbar junction burst fracture stability: a biomechanical perspective

Authors

DOI:

https://doi.org/10.25305/unj.303393

Keywords:

burst fracture, thoracolumbar junction, transpedicular stabilization, finite element analysis, biomechanical properties, minimally invasive surgery

Abstract

Introduction. The treatment of burst fractures at the thoracolumbar junction remains a contentious issue in vertebrology. Despite a broad array of surgical interventions available, many surgeons favor isolated posterior stabilization, which can be performed using either minimally invasive or open approaches. However, the biomechanical properties of these methods have not been thoroughly investigated.

Objective: This study aims to evaluate the biomechanical stability of the thoracolumbar junction following transpedicular stabilization of a burst fracture at the Th12 vertebra, under different system configurations influenced by lateral flexion.

Materials and Methods: A mathematical finite element model of the human thoracolumbar spine, featuring a burst fracture at the Th12 vertebra, was developed. The model included a transpedicular stabilization system with eight screws, simulating “long” stabilization. We examined four variants of transpedicular fixation using both mono- and bicortical screws, with and without the inclusion of two cross-links.

Results: The study found that the load borne by the damaged Th12 vertebral body varied depending on the fixation system employed. Specifically, stress levels were 24.0 MPa, 27.3 MPa, 18.4 MPa, and 25.8 MPa for models with short screws without cross-links, long screws without cross-links, short screws with cross-links, and long screws with cross-links, respectively. At the screw entry points in the vertebral arch, the highest stress values were recorded at the L2 vertebra, showing 11.8 MPa, 14.0 MPa, 9.4 MPa, and 13.4 MPa for each respective model. Among the metal construct elements, the connecting rods consistently exhibited the highest stress, with values of 226.7 MPa, 313.4 MPa, 212.4 MPa, and 293.98 MPa, respectively.

Conclusion: The results underscore that utilizing cross-links in the stabilization of burst fractures at the thoracolumbar junction, which is only feasible through an open installation, somewhat mitigates stress within the stabilized spinal segment. Meanwhile, the modeling of lateral flexion revealed only minimal differences in stress values between open and minimally invasive installations.

References

1. Holdsworth F. Fractures, dislocations, and fracture-dislocations of the spine. J Bone Joint Surg Am. 1970 Dec;52(8):1534-51. [PubMed]

2. Denis F. The three column spine and its significance in the classification of acute thoracolumbar spinal injuries. Spine (Phila Pa 1976). 1983 Nov-Dec;8(8):817-31. [CrossRef] [PubMed]

3. Dai LY, Jiang SD, Wang XY, Jiang LS. A review of the management of thoracolumbar burst fractures. Surg Neurol. 2007 Mar;67(3):221-31; discussion 231. [CrossRef] [PubMed]

4. Tanasansomboon T, Kittipibul T, Limthongkul W, Yingsakmongkol W, Kotheeranurak V, Singhatanadgige W. Thoracolumbar Burst Fracture without Neurological Deficit: Review of Controversies and Current Evidence of Treatment. World Neurosurg. 2022 Jun;162:29-35. [CrossRef] [PubMed]

5. Aras EL, Bunger C, Hansen ES, Søgaard R. Cost-Effectiveness of Surgical Versus Conservative Treatment for Thoracolumbar Burst Fractures. Spine (Phila Pa 1976). 2016 Feb;41(4):337-43. [CrossRef] [PubMed]

6. Qiu TX, Tan KW, Lee VS, Teo EC. Investigation of thoracolumbar T12-L1 burst fracture mechanism using finite element method. Med Eng Phys. 2006 Sep;28(7):656-64. [CrossRef] [PubMed]

7. Wang H, Zhang Y, Xiang Q, Wang X, Li C, Xiong H, Zhou Y. Epidemiology of traumatic spinal fractures: experience from medical university-affiliated hospitals in Chongqing, China, 2001-2010. J Neurosurg Spine. 2012 Nov;17(5):459-68. [CrossRef] [PubMed]

8. Bruno AG, Burkhart K, Allaire B, Anderson DE, Bouxsein ML. Spinal Loading Patterns From Biomechanical Modeling Explain the High Incidence of Vertebral Fractures in the Thoracolumbar Region. J Bone Miner Res. 2017 Jun;32(6):1282-1290. [CrossRef] [PubMed] [PubMed Central]

9. Ko S, Jung S, Song S, Kim JY, Kwon J. Long-term follow-up results in patients with thoracolumbar unstable burst fracture treated with temporary posterior instrumentation without fusion and implant removal surgery: Follow-up results for at least 10 years. Medicine (Baltimore). 2020 Apr;99(16):e19780. [CrossRef] [PubMed] [PubMed Central]

10. Lu J, Chen Y, Hu M, Sun C. Systematic review and meta-analysis of the effect of using percutaneous pedicle screw internal fixation for thoracolumbar fractures. Ann Palliat Med. 2022 Jan;11(1):250-259. [CrossRef] [PubMed]

11. Walker CT, Xu DS, Godzik J, Turner JD, Uribe JS, Smith WD. Minimally invasive surgery for thoracolumbar spinal trauma. Ann Transl Med. 2018 Mar;6(6):102. [CrossRef] [PubMed] [PubMed Central]

12. Perna A, Santagada DA, Bocchi MB, Zirio G, Proietti L, Tamburrelli FC, Genitiempo M. Early loss of angular kyphosis correction in patients with thoracolumbar vertebral burst (A3-A4) fractures who underwent percutaneous pedicle screws fixation. J Orthop. 2021 Feb 21;24:77-81. [CrossRef] [PubMed] [PubMed Central]

13. Alkosha HM, Omar SA, Albayar A, Awad BI. Candidates for Percutaneous Screw Fixation Without Fusion in Thoracolumbar Fractures: A Retrospective Matched Cohort Study. Global Spine J. 2020 Dec;10(8):982-991. [CrossRef] [PubMed] [PubMed Central]

14. Cornaz F, Widmer J, Snedeker JG, Spirig JM, Farshad M. Cross-links in posterior pedicle screw-rod instrumentation of the spine: a systematic review on mechanical, biomechanical, numerical and clinical studies. Eur Spine J. 2021 Jan;30(1):34-49. [CrossRef] [PubMed]

15. Nekhlopochyn O, Verbov V, Cheshuk I, Karpinsky M, Yaresko O. Mathematical Modeling of Variants of Transpedicular Fixation at the Thoracolumbar Junction after ТhХІІ Vertebrectomy during Trunk Backward Bending. ORTHOPAEDICS TRAUMATOLOGY and PROSTHETICS. 2023;(2):43-49. [CrossRef]

16. Nekhlopochyn OS, Verbov VV, Cheshuk IV, Karpinsky MY, Yaresko OV. Finite Element Analysis of Thoracolumbar Junction Transpedicular Fixation Variants after Resection of the Th12 Vertebra While Forward Bending. Bulletin of Problems Biology and Medicine. 2023;169(2):281-287. [CrossRef]

17. Ayturk UM, Puttlitz CM. Parametric convergence sensitivity and validation of a finite element model of the human lumbar spine. Comput Methods Biomech Biomed Engin. 2011 Aug;14(8):695-705. [CrossRef] [PubMed]

18. Boccaccio A, Pappalettere C. Mechanobiology of Fracture Healing: Basic Principles and Applications in Orthodontics and Orthopaedics. In: Klika V, editor. Theoretical Biomechanics. Croatia: InTech; 2011. p. 21-48. [CrossRef]

19. Cowin SC. Bone Mechanics Handbook. 2nd ed. Boca Raton: CRC Press; 2001. 980 p.

20. ISO 5832-3:2021: Implants for Surgery: Metallic Materials. Part 3: Wrought titanium 6-aluminium 4-vanadium alloy [Internet]. International Organization for Standardization. Geneva: ISO; 2021. 17 p. https://www.iso.org/ru/standard/79626.html

21. Rao SS. The Finite Element Method in Engineering: Elsevier Science; 2005. 663 p.

22. Kurowski PM. Engineering Analysis with COSMOSWorks Professional 2007. SCD Publications; 2007. 263 p.

23. Mirzaei F, Iranmehr A, Shokouhi G, Khadivi M, Shakeri M, Namvar M, Rafiei E, Matloubi B. The role of cross-link augmentation on fusion rate and patient satisfaction among patients with traumatic thoracolumbar spinal fracture: A randomized clinical trial. Neurocirugia (Astur : Engl Ed). 2021 Mar 3:S1130-1473(21)00011-7. English, Spanish. [CrossRef] [PubMed]

24. Karami KJ, Buckenmeyer LE, Kiapour AM, Kelkar PS, Goel VK, Demetropoulos CK, Soo TM. Biomechanical evaluation of the pedicle screw insertion depth effect on screw stability under cyclic loading and subsequent pullout. J Spinal Disord Tech. 2015 Apr;28(3):E133-9. [CrossRef] [PubMed]

25. Shibasaki Y, Tsutsui S, Yamamoto E, Murakami K, Yoshida M, Yamada H. A bicortical pedicle screw in the caudad trajectory is the best option for the fixation of an osteoporotic vertebra: An in-vitro experimental study using synthetic lumbar osteoporotic bone models. Clin Biomech (Bristol, Avon). 2020 Feb;72:150-154. [CrossRef] [PubMed]

26. Niinomi M. Mechanical biocompatibilities of titanium alloys for biomedical applications. J Mech Behav Biomed Mater. 2008 Jan;1(1):30-42. [CrossRef] [PubMed]

Downloads

Published

2024-09-29

How to Cite

Nekhlopochyn, O. S., Verbov, V. V., Cheshuk, I. V., Vorodi, M. V., Karpinsky, M. Y., & Yaresko, O. V. (2024). Impact of transpedicular fixation on thoracolumbar junction burst fracture stability: a biomechanical perspective. Ukrainian Neurosurgical Journal, 30(3), 30–37. https://doi.org/10.25305/unj.303393

Issue

Section

Original articles