Numerical Analysis of 3D Model of Spinal Cord in Syringomyelia Disease Conditions Using Fluid-Solid Interface Technique

Syrinx growth in Syringomyelia desease causes progressive neurological disorders. Thus, the examination of effective factors in syrinx development is so important for controlling this desease. One of clinical assumptions related to the reason of syrinx development, considers the propagation of pressure wave shock in subarachnoid-space fluid as the main reason for fluid motion in syrinx and syrinx development and increasing damage to spinal cord. Modeling and analysis have been performed to test the theory in this research using finite element method. So a 3d model was created including syrinx, spinal cord, cerebrospinal-fluid in subarachnoid-space, dura mater and stenosis. Pressure puls stimulation was applied to the superior surface of the subarachnoid-space fluid model simulating arterial puls of skull. Cerebrospinal-fluid has been assumed as a Newtonian fluid with laminar flow. The solid phase has been considered to be linear elastic. The fluid-solid interface was analized using ADINA software and fluid flow characteristics were extracted including velocity and pressure field as well as tissue stresses. Results show that pressure wave propagation in subarachnoid-space fluid causes the induction of motion in syrinx fluid, and stress concentration is created in spinal tissue due to the fluid cessation in syrinx and increasing local pressure, however these stress values are lower than spinal tissue strength and pressure wave propagation in this situation cannot be the main reason of syrinx development.