Effect of a Pedicle Screw Fixation System on Lumbar Spinal Segments: A Finite Element Study


Akıncı S. Z., Karabulut D., Doğru S. C., Sürmen H. K., Yaman O., Arslan Y. Z.

Türkiye Klinikleri Tıp Bilimleri Dergisi, cilt.43, sa.4, ss.372-381, 2023 (Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 43 Sayı: 4
  • Basım Tarihi: 2023
  • Doi Numarası: 10.5336/medsci.2023-99005
  • Dergi Adı: Türkiye Klinikleri Tıp Bilimleri Dergisi
  • Derginin Tarandığı İndeksler: Scopus, CAB Abstracts, CINAHL, Veterinary Science Database
  • Sayfa Sayıları: ss.372-381
  • İstanbul Üniversitesi-Cerrahpaşa Adresli: Evet

Özet

ABSTRACT Objective: Spinal implants have been used to stimulate fusion by surgical adjustment and correct abnormal alignment of the vertebral column. Spinal fusion can cause some spinal disorders and hence describing the changes in biomechanical forces would help to understand these complications. In this study, we used two lumbar models. One of them is used without the fixed pedicle screw system, and the other one was used with that system. Therefore, we aimed to investigate the biomechanical effect of a pedicle screw fixation system on the lumbar functional spinal unit under applied forces. Material and Methods: Computed tomography data of a scoliotic patient was used for the construction of the lumbar models. The second and third vertebrae (L2-L3) of the lumbar spine, two facet joints, an intervertebral disc, and ligaments were constructed. A screw fixation system was employed and Von-Mises stress analysis was carried out for both models. Results: The von Mises stress distribution results showed that the presence of fixed implantation transmitted the compressive forces to the screws and rods in all directions and decreased the stress levels considerably by allowing to stabilize the model. The upper side of the L2 vertebra was the most affected region in flexion and lateral bending. However, the pedicle region had the maximum affected area under applied loads in extension and axial rotation. Conclusion: It was concluded that a fixed implant system preserves the maintenance of the vertebral column and decreases the stress on the adjacent spinal segments, especially for the intervertebral discs.