Limiting interpedicular screw displacement increases shear forces in screws: A finite element study

L V P C Lima1, Y P Charles2, P Rouch3

  • 1Institut de biomécanique humaine Georges-Charpak/LBM, arts et métiers ParisTech, 151, boulevard de l'Hôpital, 75013 Paris, France; Universidade Estadual do Rio de Janeiro, Instituto Politécnico Rua Bonfim, 25, Vila Amélia, 28.625-570 Nova Friburgo, RJ, Brazil.

Summary

Posterior spinal implants allowing interpedicular displacement (ID) showed reduced screw loosening. Future designs should balance stiffness for load-bearing with controlled ID to enhance spinal fusion device longevity.

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