Modelling and Analysis of the Cerebrospinal Fluid Flow in the Spinal Cord

The cerebrospinal fluid (CSF) flow in the spinal cord is important in maintaining the stability of the central nervous system. However, the interaction between CSF and spinal cord is not well understood. A three-dimensional (3D) simplified finite element model (FEM) of a sheep CSF and spinal cord segment was developed, verified using clinical experimental data, and used to investigate the effect of deformations and stress distributions on spinal cord in normal physiological conditions. The commercial software ANSYS Workbench was adopted to simulate the unidirectional CSF flow along the coaxial tube, which considered the bi-directional fluid-solid coupling. It was demonstrated that CSF had a slight impact on the spinal cord, which was transmitted to the white and gray matter through the pia mater. The pia mater protected the normal physiological function of the white and gray matter while the spinal dura mater ensured the regular rate and pressure of CSF. It was also showed that the CSF flow in the spinal cord was laminar. This model might help us to better understand the mechanism of interaction between CSF and spinal cord and provide a baseline for mechanical comparisons in spinal cord injury.