Izvorni znanstveni članak
https://doi.org/10.3325/cmj.2021.62.328
Biomechanical stability analysis of transpedicular screws combined with sublaminar hook-rod system using the finite element method
Krešimir Saša Đurić
; Department of Neurosurgery, Clinical Hospital Center Zagreb, Zagreb, Croatia
Josip Rauker
; Medical 3D Design, Zagreb, Croatia
Hrvoje Barić
; Department of Neurosurgery, Clinical Hospital Center Zagreb, Zagreb, Croatia
Ivan Pašalić
; Department of Neurosurgery, Clinical Hospital Center Zagreb, Zagreb, Croatia
Ivan Domazet
; Department of Neurosurgery, Clinical Hospital Center Zagreb, Zagreb, Croatia
Petra Barl
; Department of Neurosurgery, Clinical Hospital Center Zagreb, Zagreb, Croatia
Jurica Sorić
; Faculty of Mechanical Engineering, Zagreb University, Zagreb, Croatia
Marin Stančić
; Department of Neurosurgery, Clinical Hospital Center Zagreb, Zagreb, Croatia
Sažetak
Aim To develop and test a new posterior stabilization system by augmenting the posterior hook-rod system with
screws and rods.
Methods A biomechanical analysis was performed using
the finite element method. The anatomical structures were
modeled based on computed tomography data. Instrumentation (hooks, rods, and screws) was modeled based
on the data obtained by 3D scanning. The discretized
model was verified by converging solutions and validated against data from a previously published experiment.
A Th12-L1 spinal segment was modeled and modified by
removing the body of the L1 vertebra (corpectomy) and
the entire L1 vertebra (spondylectomy). The model was
additionally modified by incorporating stabilization systems: i) posterior stabilization (transpedicular screws and
rods); ii) combined posterior stabilization with sublaminar
hooks; and iii) combined anterior (titanium cage) and posterior (sublaminar hooks) stabilization. The rotation angles
in each group, and the strains on each part of the three stabilization constructs, were analyzed separately.
Results The combined anterior and posterior stabilization
system was the stiffest, except in the case of lateral bending, where combined posterior stabilization was superior.
Stress analysis showed that the posterior stabilization system was significantly unloaded when augmented with a
hook-rod system. A significant strain concentration was
calculated in the cranially placed hooks.
Conclusion Stiffness analysis showed comparable stiffness between the tested and proposed stabilization construct. Stress analysis showed luxation tendency of the
cranially placed hooks, which would most likely lead to
system failure.
Ključne riječi
Hrčak ID:
278146
URI
Datum izdavanja:
26.8.2021.
Posjeta: 322 *