title: Biomechanical analysis and design of a dynamic spinal fixator using topology optimization: a finite element analysis.
abstract: Surgeons often use spinal fixators to manage spinal instability. Dynesys (DY) is a type of dynamic fixator that is designed to restore spinal stability and to provide flexibility. The aim of this study was to design a new spinal fixator using topology optimization [the topology design (TD) system]. Here, we constructed finite element (FE) models of degenerative disc disease, DY, and the TD system. A hybrid-controlled analysis was applied to each of the three FE models. The rod structure of the topology optimization was modelled at a 39 % reduced volume compared with the rigid rod. The TD system was similar to the DY system in terms of stiffness. In contrast, the TD system reduced the cranial adjacent disc stress and facet contact force at the adjacent level. The TD system also reduced pedicle screw stresses in flexion, extension, and lateral bending.
authors.affiliation: Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Hung-Ming
authors.initials: HM
authors.lastname: Lin
authors.forename: Chien-Lin
authors.initials: CL
authors.lastname: Liu
authors.forename: Yung-Ning
authors.initials: YN
authors.lastname: Pan
authors.forename: Chang-Hung
authors.initials: CH
authors.lastname: Huang
authors.forename: Shih-Liang
authors.initials: SL
authors.lastname: Shih
authors.forename: Shun-Hwa
authors.initials: SH
authors.lastname: Wei
authors.forename: Chen-Sheng
authors.initials: CS
authors.lastname: Chen
mesh_terms: D001696:Biomechanical Phenomena; D004867:Equipment Design / Q000379:methods*; D020342:Finite Element Analysis; D006801:Humans; D016268:Internal Fixators; D055959:Intervertebral Disc Degeneration / Q000601:surgery; D008159:Lumbar Vertebrae / Q000601:surgery; D008954:Models, Biological; D013123:Spinal Fusion / Q000295:instrumentation*
references.citation: Eur Spine J. 2006 Jun;15(6):913-22
references.pmid: 16217663
references.citation: Spine (Phila Pa 1976). 1996 Apr 1;21(7):811-9; discussion 820
references.pmid: 8779011
references.citation: Eur Spine J. 2006 Jun;15(6):720-30
references.pmid: 16328226
references.citation: Spine (Phila Pa 1976). 1999 Sep 1;24(17):1820-32
references.pmid: 10488513
references.citation: Eur Spine J. 2006 Aug;15(8):1276-85
references.pmid: 16429291
references.citation: Eur Spine J. 2009 Jun;18 Suppl 1:40-8
references.pmid: 19396475
references.citation: Spine (Phila Pa 1976). 2008 Jan 1;33(1):19-26
references.pmid: 18165744
references.citation: Eur Spine J. 2002 Oct;11 Suppl 2:S157-63
references.pmid: 12384739
references.citation: Adv Orthop. 2013;2013:451956
references.pmid: 23606975
references.citation: Eur Spine J. 2007 Aug;16(8):1223-31
references.pmid: 17206401
references.citation: Eur Spine J. 2013 Mar;22 Suppl 2:S232-41
references.pmid: 22573049
references.citation: Spine (Phila Pa 1976). 2008 Feb 1;33(3):E66-72
references.pmid: 18303447
references.citation: Arch Orthop Trauma Surg. 1999;119(3-4):127-32
references.pmid: 10392504
references.citation: Spine (Phila Pa 1976). 2005 Dec 15;30(24):2755-64
references.pmid: 16371899
references.citation: Spine (Phila Pa 1976). 2007 Dec 15;32(26):3014-9
references.pmid: 18091495
references.citation: Spine J. 2009 Jan-Feb;9(1):96-102
references.pmid: 18440280
references.citation: Eur Spine J. 2011 Nov;20(11):1850-8
references.pmid: 21523456
references.citation: SAS J. 2007 Feb 01;1(1):46-54
references.pmid: 25802578
references.citation: J Biomed Mater Res A. 2007 Nov;83(2):272-9
references.pmid: 17415762
references.citation: Spine (Phila Pa 1976). 1996 Apr 15;21(8):970-81
references.pmid: 8726202
references.citation: Med Eng Phys. 2011 May;33(4):490-6
references.pmid: 21177135
references.citation: Clin Biomech (Bristol, Avon). 2006 Oct;21(8):767-74
references.pmid: 16750875
references.citation: Am J Orthop (Belle Mead NJ). 1999 Jun;28(6):336-40
references.pmid: 10401898
references.citation: Proc Inst Mech Eng H. 2009 Feb;223(2):143-57
references.pmid: 19278192
references.citation: Med Eng Phys. 2012 Sep;34(7):999-1008
references.pmid: 22770748
references.citation: Spine (Phila Pa 1976). 2007 Jan 1;32(1):55-62
references.pmid: 17202893
references.citation: J Spinal Disord Tech. 2003 Aug;16(4):418-23
references.pmid: 12902959
references.citation: Spine (Phila Pa 1976). 1989 Nov;14(11):1256-60
references.pmid: 2603060
references.citation: J Spinal Disord Tech. 2010 Aug;23(6):410-7
references.pmid: 20683426
references.citation: Eur Spine J. 2011 Apr;20(4):578-84
references.pmid: 21125299
references.citation: Spine (Phila Pa 1976). 2001 Dec 1;26(23):2521-32; discussion 2532-4
references.pmid: 11725230
references.citation: Spine (Phila Pa 1976). 2012 May 1;37(10):E581-9
references.pmid: 22198353
references.citation: Comput Biol Med. 2013 Sep;43(9):1234-40
references.pmid: 23930818
references.citation: Med Eng Phys. 2009 Mar;31(2):244-53
references.pmid: 18760654
references.citation: Spine (Phila Pa 1976). 2008 Aug 15;33(18):E636-42
references.pmid: 18708915
references.citation: Med Eng Phys. 2006 Jan;28(1):90-8
references.pmid: 16426979
references.citation: Spine (Phila Pa 1976). 2007 May 20;32(12):1311-9
references.pmid: 17515820
references.citation: J Spinal Disord Tech. 2011 Feb;24(1):60-7
references.pmid: 21270627
references.citation: Eur Spine J. 2002 Oct;11 Suppl 2:S170-8
references.pmid: 12384741
references.citation: Biomed Mater. 2011 Oct;6(5):055005
references.pmid: 21849724