Prediction of Spinal Alignment with Different Instruments Using Fea

*Liu, X.-C.; +**Rizza, R.; *Thometz, J.; *Tassone, C. *Dept. of Orthopaedic Surgery, Medical College of Wisconsin. +**Dept. of Mechanical Engineering, Milwaukee School of Engineering, Milwaukee, WI [email protected] INTRODUCTION: For the treatment of scoliosis, traditional instrumentations such as Cotrel-Dubousset are very rigid and effect spine growth. Recently, spinal Fusionless instrumentation has been clinically introduced. These instrumentations are more spring-like (compliant). However, whether the instrumentation is rigid or compliant the growth of the spine is effected. The actual level of instrument stiffness that affects growth is not known nor well quantified. The goals of this study were, by using FEA, to examine the effect of the level of instrumentation stiffness as well as the position of the screws on the growth of pig spine and to quantify the rotation of the vertebrae with respect to spring type or plate type instrumentation.