Comparison of rigid and semi-rigid instrumentation under acute load on vertebrae treated with posterior lumbar interbody fusion/transforaminal lumbar interbody fusion procedures: An experimental study
Onen, Mehmet Resid and Basgul, Cemile and Yilmaz, Ilhan and Ozkaya,
Mustafa and Demir, Teyfik and Naderi, Sait
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Abstract
Rigid and semi-rigid fixations are investigated several times in order
to compare their biomechanical stability. Interbody fusion techniques
are also preferable for maintaining the sagittal balance by protecting
the disk height. In this study, the biomechanical comparison of
semi-rigid and rigid fixations with posterior lumbar interbody fusion or
transforaminal lumbar interbody fusion procedures is conducted under
trauma. There were four different test groups to analyze the effect of
acute load on treated ovine vertebrae. First and second groups were
fixed with polyetheretherketone rods and transforaminal lumbar interbody
fusion and posterior lumbar interbody fusion cages, respectively. Third
and fourth groups were fixed with titanium rods and posterior lumbar
interbody fusion and transforaminal lumbar interbody fusion cages,
respectively. The drop tests were conducted with 7kg weight. There were
six samples in each group so the drop test repeated 24 times in total.
The test samples were photographed and X-rayed (laterally and
anteroposteriorly) before and after drop test. Two fractures were
observed on group 1. Conversely, there were no fractures observed for
group 2. There were no anterior element fractures for both groups 1 and
2. However, one fracture seen on group 3 was anterior element fracture,
whereas the other three were posterior element fractures. All three
fractures were anterior element fractures for group 4. Treated vertebrae
with polyetheretherketone rods and posterior lumbar interbody fusion
cages showed the best durability to the drop tests among the groups.
Semi-rigid fixation gave better results than rigid fixation according to
failed segments. Posterior lumbar interbody fusion cages seem to be
better option for semi-rigid fixation, however mentioned surgical
disadvantages must be considered.... Show more Show less