Journal of Biomedical Engineering Research (대한의용생체공학회:의공학회지)

The Korean Society of Medical and Biological Engineering (대한의용생체공학회)
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Biomechanical Analysis of a Combined Interspinous Spacer with a Posterior Lumbar Fusion with Pedicle Screws

척추경나사못을 이용한 유합술과 동반 시술된 극돌기간 삽입기구의 생체역학적 연구

  • Kim, Y.H. (Center for Food & Drug Analysis, Ministry of Food and Drug Safety) ;
  • Park, E.Y. (Department of Medical Device Evaluaion, Ministry of Food and Drug Safety) ;
  • Lee, S.J. (Department of Biomedical Engineering, Inje University)
  • 김영현 (부산지방식품의약품안전청 시험분석센터) ;
  • 박은영 (식품의약품안전평가원 의료기기심사부) ;
  • 이성재 (인제대학교 의용공학부)
  • Received : 2015.10.14
  • Accepted : 2015.12.09
  • Published : 2015.12.31
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Abstract

Recently, during the multi-level fusion with pedicle screws, interspinous spacer are sometimes substituted for the most superior level of the fusion in an attempt to reduce the number of fusion level and likelihood of degeneration process at the adjacent level. In this study, a finite element (FE) study was performed to assess biomechanical efficacies of the interspinous spacer combined with posterior lumbar fusion with a previously-validated 3-dimensional FE model of the intact lumbar spine (L1-S1). The post-operative models were made by modifying the intact model to simulate the implantation of interspinous spacer and pedicle screws at the L3-4 and L4-5. Four different configurations of the post-op model were considered: (1) a normal spinal model; (2) Type 1, one-level fusion using posterior pedicle screws at the L4-5; (3) Type 2, two-level (L3-5) fusion; (4) Type 3, Type 1 plus Coflex$^{TM}$ at the L3-4. hybrid protocol (intact: 10 Nm) with a compressive follower load of 400N were used to flex, extend, axially rotate and laterally bend the FE model. As compared to the intact model, Type 2 showed the greatest increase in Range of motion (ROM) at the adjacent level (L2-3), followed Type 3, and Type 1 depending on the loading type. At L3-4, ROM of Type 2 was reduced by 34~56% regardless of loading mode, as compared to decrease of 55% in Type 3 only in extension. In case of normal bone strength model (Type 3_Normal), PVMS at the process and the pedicle remained less than 20% of their yield strengths regardless of loading, except in extension (about 35%). However, for the osteoporotic model (Type 3_Osteoporotic), it reached up to 56% in extension indicating increased susceptibility to fracture. This study suggested that substitution of the superior level fusion with the interspinous spacer in multi-level fusion may be able to offer similar biomechanical outcome and stability while reducing likelihood of adjacent level degeneration.

Keywords

References

  1. A.S. Hilibrand, N. Rand, "Degenrative lumbar stenosis: Diagnosis and management," J Am Acad Orthop Surg, vol. 7, no. 4, pp. 239-249, 1999. https://doi.org/10.5435/00124635-199907000-00004
  2. I. Oda, B.W. cunningham, G.A. Lee, "Biomechanical properties of anterior thoracolumbar multi-segmental fixation," Spine, vol. 25, no. 18, pp. 2303-2311, 2000. https://doi.org/10.1097/00007632-200009150-00007
  3. T. Akamura, N. Kawahara, S.T. Yoon, A. Minamide, K.S. Kim, K. Tomita, W. Hutton, "Adjacent segment motion after a simulated lumbar fusion in different sagittal alignment," Spine, vol. 28, pp. 1560-1566, 2003.
  4. D.H. Chow, K.D. Luk, J.H. Evans, J.C. Leong, "Effects of short anterior lumbar interbody fusion on biomechanics of neighboring unfused segment," Spine, vol. 21, pp. 549-555, 1996. https://doi.org/10.1097/00007632-199603010-00004
  5. D.C. Kim, W.J. Choe, S.K. Jang, "Preliminary report on usefulness of adjacent interpinous stabilization using interspinous spacer combined with posterior lumbosacral spinal fusion in degenerative lumbar disease," Korean J Spine, vol. 9, no. 3, pp. 149-155, 2009.
  6. R.J. Crawford, R.I. Price, K.P. singer, "Surgical treatment of lumbar segment disease with interspinous implant: review," Journal of Musculoskeletal Research, vol. 12, no. 3, pp. 153-167, 2009. https://doi.org/10.1142/S0218957709002328
  7. J.H. Park, S. Heo, K. Son, S.J. Lee, "Biomechanical analysis of lumbar interspinous process fixators and design of miniaturization and advanced flexibility," Transactions of the Korean Society of Mechanical Engineers A, vol. 30, issue 12, pp. 1509-1517, 2006. https://doi.org/10.3795/KSME-A.2006.30.12.1509
  8. W.M. Chen, C.K. Park, K.Y. Lee, S.J. Lee, "In situ contact analysis of the prosthesis components of Prodisc-L in lumbar spine following total disc replacement," Spine, vol. 34, no. 20, pp. 716-723, 2009. https://doi.org/10.1097/BRS.0b013e3181ae23d1
  9. Y.H. Kim, T.G. Jung, E.Y. Park, G.W. Kang, K.A. Kim, S.J. Lee, "Biomechanical efficacy of a combined interspinous fusion system with a lumbar interbody fusion cage," International Journal of Precision Engineering and Manufacturing, vol. 16, no. 5, pp. 997-1001, 2015. https://doi.org/10.1007/s12541-015-0129-7
  10. T. Zander, A. Rohlmann, J. Calisse, G. Bergmann, "Estimation of muscle forces in the lumbar spine during upper-body inclination," Clinical Biomechanics, vol. 16, pp. 73-80, 2001. https://doi.org/10.1016/S0268-0033(00)00108-X
  11. V.K. Goel, B.T. Monroe, L.G. Gilberton, P. Brinckmann, "Interlaminal shear stresses and laminae separation in a disk: Finite element analysis of the L-L4 motion segment subjected to axial compressive loads," Spine, vol. 20, pp. 689-698, 1995. https://doi.org/10.1097/00007632-199503150-00010
  12. S.A. Shirazi-Adl, S.C. Shrivastava, A.M. Ahmed, "Stress analysis of the lumbar disc-body unit in compression a treedimensional nonlinear finite element study," Spine, vol. 9, pp. 120-134, 1984. https://doi.org/10.1097/00007632-198403000-00003
  13. M. Sharma, N.A. Langrana, J. Rodreguez, "Role of ligaments and facets in lumbar spinal stability," Spine, vol. 20, pp. 887-900, 1995. https://doi.org/10.1097/00007632-199504150-00003
  14. T.H. Smit, A. Odgaard, E. Schneider, "Structue and Function of Vertebral Trabecular bone," Spine, vol. 22, pp. 2823-2833, 1997. https://doi.org/10.1097/00007632-199712150-00005
  15. Y.H. Ahn, W.M. Chen, D.Y. Jung, K.W. Park, S.J. Lee,, "Biomechanical effects of posterior dynamic stabilization system on lumbar kinematic: a finite element analysis," J. Biomed. Eng. Res, vol. 29, pp. 139-145, 2008.
  16. Y.H. Kim, K.S. Ryu, K.Y. Lee, S.J. Lee, "Biomechanical Efficacies of an Interspinous Spacer combined with Posteiror Lumbar Fusion with Pedicle Screws," Orthopadic Research Society 2013 Anuual Meeting, Poster no. 0817, 2013.
  17. A. Polikeit, L.P. Nolte, S.J. Ferguson, "The effect of cement augmentation on the load transfer in an osteoporotic functional spinal unit: finite element analysis," Spine, vol. 28, pp. 991-996, 2003.
  18. M.M. Panjabi, V.K. Goel, "Adjacent-level effects: Design of a new test protocol and finite element model simulations of disc replacement," Roundtables in Spine Surgery; Spine Biomechanics, St Louis, MO: Quality Medical Publishing, pp. 45-58, 2008.
  19. Y.H. Kim, S.C. Jun, D.Y. Jung, S.J. Lee, "Biomechanical analysis of different thoracolumbar orthosis designs using finite element method," Journal of Rehabilitation, Welfare Engineering & Assistive Technology, vol. 6, no. 1, pp. 45-50, 2012.
  20. H. Lin, G. Zhang, H. Wu, N. Liu, Z. Zha, "Treatment of bisegmental lumbar spinal stenosis: Coflex interspinous implant versus bisegmental posterior lumbar interbody fusion," Scientific Research and Essays, vol. 6 pp. 479-484, 2011.
  21. A. Kettler, J. Drumm, F, Heuer, K. Haeussler, C. Mack, L. Claes, H-J. Wilke, "Can a modified interspinous spacer prevent instability in axial rotation and lateral bending? a biomechanical in vitro study resulting in a new idea," Clinical Biomechanics, vol. 23, pp. 242-247, 2008. https://doi.org/10.1016/j.clinbiomech.2007.09.004