Enhancement and Evaluation of Fatigue Resistance for Spine Fixation System

척추고정장치의 피로성능 평가와 향상

  • 김현묵 ((주)오티스바이오텍 인공관절연구소) ;
  • 김성곤 (고려대학교 의과대학 정형외과)
  • Published : 2009.08.01

Abstract

Spinal fixation systems provide surgical versatility, but the complexity of their design reduces their strength and fatigue resistance. There is no published data on the mechanical properties of such screws. Screws were assembled according to a vertebrectomy model for destructive mechanical testing. A group of two assemblies was tested in static compression. One group was applied to surface a grit blasting method and another group was applied to surface a bead blasting method. Modes of failure, yield, and ultimate strength, yield stiffness, and cycles to failure were determined for six assembles. Static compression 2% offset yield load ranges was from 327 to 419N. Fatigue loads were determined two levels, 37.5% and 50% of the average load from static compression ultimate load. An assembly of bead blasting treatment only achieved 5 million cycles at 37.5% level in compression bending.

Keywords

References

  1. Boucher, H., "A Method of Spinal Fusion," J. Bone Joint Surg., Vol. 41B, No. 2, pp. 248-259, 1959
  2. Cotler, J. M., "Spine Instrumentation:Historical Events Leading to Spine Surgery," Lippincott Williams & Wilkins, p. 592, 1999
  3. Roy, C. R., Saillant, G. and Mazel, C., "Internal Fixation of the Lumbar Spine with Pedicle Screw Plating," J. of Clin. Orthop., Vol. 203, pp. 7-17, 1987
  4. Kanayama, M., Cunningham, B. W. and Sefter J. C., "Dose Spinal Instrumentation Influence the Healing Process of Posterolateral Spinal Fusion: An in Vivo Animal Model," Spine, Vol. 24, No. 11, pp. 1058-1065, 1999 https://doi.org/10.1097/00007632-199906010-00003
  5. Thomsen, K., Christensen, F. B. and Eiskjaer, S. P., "The Effect of Pedicle Screw Instrumentation on Functional Outcome and Fusion Rates in Posterolateral Lumbar Spinal Fusion:a prospective, randomized clinical study," Spine, Vol. 22, No. 24, pp. 2813-2822, 1997 https://doi.org/10.1097/00007632-199712150-00004
  6. Vaccaro, A. R. and Garfin, S. R., "Internal Fixation(pedicle screw fixation) for Fusions of the Lumbar Spine," Spine, Vol. 20, No. 24, pp. 157-165, 1995 https://doi.org/10.1097/00007632-199512151-00013
  7. Yahiro, M. A., "Comprehensive Literature Review: Pedicle Screw Fixation Devices," Spine, Vol. 19, No. 20, pp. 2274S-2278S, 1994 https://doi.org/10.1097/00007632-199410151-00004
  8. Yuan, H. A., Garfin, S. R. and Dickman, C. A., "A Historical Cohort Study of Pedicle Screw Fixation in Thoracic, Lumbar, and Sacral Spinal Fusions," Spine, Vol. 19, No. 20, pp. 2279S-2296S, 1994 https://doi.org/10.1097/00007632-199410151-00005
  9. Panjabi, M. M., "Biomechanical Evaluation of Spinal Instrumentation," Spine, Vol. 13, No. 10, pp. 1129-1134, 1988 https://doi.org/10.1097/00007632-198810000-00013
  10. Ralph, E. S. and Philip, M. S., "Multiaxial Pedicle Screw Designs:Static and Dynamic Mechanical Testing," Spine, Vol. 29, No. 4, pp. 367-375, 2004 https://doi.org/10.1097/01.BRS.0000092369.50397.85