The Effect of Instrumentation With Different Mechanical Properties on the Pig Spine During Growth: Finite Element Analysis

For the treatment of scoliosis, traditional instrumentations such as Cotrel-Dubousset are very rigid and effect spine growth ([1] & [2]). Recently, spinal fusion-less instrumentation has been clinically introduced. These instrumentations are more spring-like (compliant). Such instrumentations include multiple level staples, vertical expanding prosthesis, and changeable rod system. 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 goal of this study was to examine the effect of the level of instrumentation stiffness on the simulation of growth of the pig spine by using finite element analysis (FEA).