Biomechanical Analysis of Lumbar Interspinous Process Fixators

요추부 극돌기간 고정기구의 생체역학적 해석

  • 허순 (부산대학교 기계설계대학원) ;
  • 박정홍 (부산대학교 기계설계대학원) ;
  • 이성재 (인제대학교 의용공학과) ;
  • 손권 (부산대학교 기계공학부)
  • Published : 2006.03.01

Abstract

The degenerative lumbar spinal stenosis (DLSS) is a disease inducing low back pain, leg pain, convulsion. numbness, and neurogenic claudication from compression of nerve root. Intervertebra fixation was reported to increase the degeneration of neighbor lesion after treatment. Recently, a new surgical technique of inserting a fixator between interspinous processes has been introduced. The purpose of this study is to design the interspinous process fixator with flexibility to complement the trouble of using fixator in DLSS. This study evaluated the existing fixator through the mechanical test and modified it using the finite element analysis (FEA). The evaluation was based on the displacement, stiffness and von-Mises stress obtained from the mechanical test and calculated from the FEA in the biomechanical loading condition. Effects of variation in length and thickness were investigated to design an optimal fixator. Three prototypes were manufactured using FEA results. Mechanical tests under the biomechanical loading condition were performed to select the best one from these three. The selected fixator increased flexiblity by 32.9%.

Keywords

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