Turkish Neurosurgery 2005 , Vol 15 , Num 2
Biomechanical Analysis of A Turkish-Made Posterior Spinal Instrumentation System
Part II. Evaluation of the Stability And Strength Provided By the Transpedicular Screw Fixation Device
1Department of Neurosurgery, School of Medicine, Trakya University, Edirne,Turkey
2Spine Research Laboratory, The Cleveland Clinic Foundation, Cleveland, OH, USA
3Department of Neurosurgery, School of Medicine, Ege University, İzmir,Turkey
OBJECTIVE: To determine the construct stability and strength provided by a Turkishmade transpedicular fixation device (TIPSAN Posterior Instrumentation System, Tıpsan Tıbbi Aletler, İzmir, Turkey) compared to another well known system (Moss-Miami System, DePuy AcroMed, Raynham, MA, USA) in lumbar calf spine.

METHODS: Six L3-L5 levels were used for each device. A posterior and middle column injury was created on L4-L5 interspace on each specimen. Pedicle screws were placed to bilateral L3, L4, and L5 levels along with rods and one cross-link. In stability testing, specimens were non-destructively tested intact, after injury, and after instrumentation at the physiologic loads using a materials testing machine. Overall stiffnesses of the specimens were calculated. In strength testing, specimens were loaded in flexion mode until failure occurred. Stability and strength performances of both devices were compared using statistical analysis.

RESULTS: The Tıpsan system showed greater stiffness in flexion. Stability performances of the two devices in extension and lateral bending were similar. Both devices showed no breakage or bending in the strength test.

CONCLUSION: The Tıpsan Posterior instrumentation system was found to have at least similar construct stability and strength performance in comparison to a well-known system and proved to have equal worth as a spinal implant. Keywords : Animal model, biomechanics, bone screws, compressive strength, lumbar vertebrae, spinal fractures, spinal fusion

Corresponding author : Cumhur Kılınçer, ckilincer@trakya.edu.tr