Photoelastic Analysis of the Vertebral Fixation System Using Different Screws


  • S. F. Fakhouri Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil
  • M. M. Shimano Department of Mechanical Engineering Federal University of Triangulo Mineiro, Brazil
  • C. A. Araujo Laboratory of Mechanical Projects Professor Henner Alberto Gomide School of Mechanical Engineering of Federal University of Uberlandia, Brazil
  • H. L. Defino Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil
  • A. C. Shimano Department of Biomechanics, Medicine and Rehabilitation of the Locomotor Apparatus Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Brazil


The purpose of this study was to compare using photoelasticity, the internal stresses produced by two types of pedicular screws (Synthes™) with three different diameters, when submitted to different pullout strengths. The fringe orders were evaluated around the screws using the Tardy compensation method. In all the models analyzed, the shear stress was calculated. Results showed that, independently of the applied load, the screw of smaller outer diameter had larger values of shear stress. According to the analysis realized, we observed that the place of highest stress was in the last thread, close to the head of the screws.


photoelasticity, biomechanics, pullout strength, vertebral fixation system


Download data is not yet available.


A. W. L. Kwok, J. A. Finkelstein, T. Woodside, T. C. Hearn, R. W. Hu, “Insertional torque and pullout strengths of conical and cylindrical pedicle screw in cadaveric bone”, Spine, Vol. 21, No. 21, pp. 2429-2434, 1996 DOI:

M. Pfeiffer, L. G. Gilbertson, V. K. Goel, P. Griss, J. C. Keller, T. C. Ryken, H. E. Hoffman, “Effect of specimen fixation method on pullout tests of pedicle screws”, Spine, Vol. 21, No. 9, pp. 1037-1044, 1996 DOI:

C. T. Vangsness Jr, D. R. Carter, V. H. Frankel, “In vitro evaluation of the loosening characteristics of self-tapped and non-selftapped cortical bone screws”, Clinical Orthopaedics and Related Research, Vol. 157, pp. 279-286, 1981 DOI:

Q. H. Zhang, S. H. Tan, S. M. Chou, “Investigation of screw pull-out strength on human spine”, Journal of Biomechanics, Vol. 37, No. 4, pp. 479-485, 2004 DOI:

T. Hirano, K. Hasegawa, H. E. Takahashi, U. Seiji, H. Toshiaki, W. Toshikatsu, S. Toru, Y. Motoo, I. Masayuki, “Structural characteristics of the pedicle and its role in screw stability”, Spine, Vol. 22, No. 21, pp. 2504-2509, 1997 DOI:

T. H. Lim, H. S. An, C. Evanich, K. Y. Hasanoglu, L. McGrady, C. R. Wilson, “Strength of anterior vertebral screw fixation in relationship to bone mineral density”, Journal of Spinal Disorders, Vol. 8, No. 2, pp. 121-125, 1995 DOI:

B. S. Myers, P. J. Belmont Jr, W. J. Richardson, J. R. Yu, K. D. Harper, R. W. Nightingale, “The role of imaging and in situ biomechanical testing in assessing pedicle screw pull-out strength”, Spine, Vol. 21, No. 17, pp. 1962-1968, 1996 DOI:

M. R. Zindrick, L. L. Wiltse, E. H. Widell, “A biomechanical study of intrapedicular screw fixation in the lumbar spine”, Clinical Orthopaedics and Related Research, Vol. 203, pp. 99-112, 1986 DOI:

P. M. Zink, “Performance of ventral spondylodesis screws in cervical vertebrae of varying bone mineral density”, Spine, Vol. 21, No. 1, pp. 45-52, 1996 DOI:

M. Law, A. F. Tencer, P. A. Anderson, “Caudo-cephalad loading of pedicle screw: mechanisms of loosening and methods of augmentation”, Spine, Vol. 18, pp. 2438-2443, 1993 DOI:

A. Alobaid, V. Arlet, A. Busato, T. Steffen, “Pull-out strength of the suprapedicle claw construct: a biomechanical study”, European Spine Journal, Vol. 14, No. 8, pp. 759-764, 2005 DOI:

C. C. Hsu, C. K. Chao, J. L. Wang, S. M. Hou, Y. T. Tsai, J. Lin, “Increase of pullout strength of spinal pedicle screws with conical core: biomechanical tests and finite element analyses”, Journal of Orthopaedic Research, Vol. 23, pp. 788-794, 2005 DOI:

B. B. Abshire, R. F. McLain, A. Valdevit, H. E. Kambic, “Characteristics of pullout failure in conical and cylindrical pedicle screws after full insertion and back-out”, Spine, Vol. 1, pp. 408-414, 2001 DOI:

C. A. Lill, E. Schneider, J. Goldhahn, A. Haslemann, F. Zeifang, “Mechanical performance of cylindrical and dual core pedicle screws in calf and human vertebrae”, Archives of orthopaedic and trauma surgery, Vol. 126, No. 10, pp. 686-694, 2006 DOI:

D. W. Bühler, U. Berlemann, T. R. Oxland, N. Lutz-Peter, “Moments and forces during pedicle screw insertion: in vitro and in vivo measurements”, Spine, Vol. 23, No. 11, pp. 1220-1227, 1998 DOI:

S. D. Cook, S. L. Salkeld, T. Stanley, A. Faciane, S. D. Miller, “Biomechanical study of pedicle screw fixation in severely osteoporotic bone”, Spine journal, Vol. 4, No. 4, pp. 402-408, 2004 DOI:

S. Eggli, “Biomechanical testing of three newly developed transpedicular multisegmental fixation systems”, European Spine Journal, Vol. 1, No. 2, pp. 109-116, 1992 DOI:

S. Soshi, R. Shiba, H. Kondo, K. Murota, “An experimental study on transpedicular screw fixation in relation to osteoporosis of the lumbar spine”, Spine, Vol. 16, No. 11, pp. 1335–1341, 1991 DOI:

J. D. Coe, “Influence of bone mineral density on the fixation of thoracolumbar implants: a comparative study of transpedicular screws, laminar hooks, and spinous process wires”, Spine, Vol. 15, No. 9, pp. 902-907, 1990 DOI:

D. B. Mahler, F. A. Peyton, “Photoelasticity as a research technique for analyzing stresses in dental structures”, Journal of Dental Research, Vol. 34, No. 6, pp. 831-838, 1955 DOI:

A. R. Mac Gregor, T. P. G. Miller, J. W. Farah, “Stress analysis of partial dentures”, Journal of Dentistry, Vol. 6, No. 2, pp. 125-132, 1978 DOI:

J. W. Dally, W. F. Riley, “Experimental stress analysis”, 1991, 3ª ed. Nova York: Mcgraw-Hill

Y. Okada, S. Ikeda, T. Fukuda, F. Arai, M. Negoro, I. Takahashi, “Photoelastic Stress Analysis on Patient-Specific Anatomical Model of Cerebral Artery”, Proceeding of the Symposium on Micro-NanoMechatronics and Human Science, pp. 538-543, 2007 DOI:

S. F. Fakhouri, C. A. Araujo, A. Zamarioli, E. Timóteo, A. C. Shimano, “Analysis of compressive distributional load of intervertebral disc L4-L5 meand of photoelasticity”, Fiep Bulletin, Vol. 79, pp. 21-23, 2009

L. E. Gayet, P. Pries, H. Hamcha, J. P. Clarac, J. Texereau, “Biomechanical study and digital modeling of traction resistance in posterior thoracic implants”, Spine, Vol. 27, pp. 707-714, 2002 DOI:

A. Ono, M. D. Brown, L. L. Latta, E. L. Milne, D. C. Holmes, “Triangulated pedicle screw construct technique and pull-out strength of conical and cylindrical screws”, Journal of spinal disorders, Vol. 14, No. 4, pp. 323-329, 2001 DOI:

S. Inceoglu, L. Ferrara, R. F. McLan, “Pedicle screw fixation strength: pullout versus insertional torque”, Spine, Vol. 4, No. 5, pp. 513-518, 2004 DOI:

J. W. Barber, S. D. Boden, T. Ganey, W. C. Hutton, “Biomechanical study of lumbar pedicle screws: does convergence affect axial pullout strength?”, Journal of Spinal Disorders, Vol. 11, No. 3, pp. 215-220, 1998 DOI:

T. A. De Coster, D. B. Heetderks, D. J. Downey, J. S. Ferries, W. Jones, “Optimizing bone screw pullout force”, Journal of Orthopaedic Trauma, Vol. 4, No. 2, pp. 169-174, 1990 DOI:

T. K. Daftari, W. C. Horton, W. C. Hutton, “Correlations between screw hole preparation, torque of insertion, and pullout strength for spinal screws”, Journal of Spinal Disorders, Vol. 7, No. 2, pp. 139-145, 1994 DOI:


How to Cite

S. F. Fakhouri, M. M. Shimano, C. A. Araujo, H. L. Defino, and A. C. Shimano, “Photoelastic Analysis of the Vertebral Fixation System Using Different Screws”, Eng. Technol. Appl. Sci. Res., vol. 2, no. 2, pp. 190–195, Apr. 2012.


Abstract Views: 609
PDF Downloads: 166

Metrics Information
Bookmark and Share