HSM-PC Users Guide

The Head Spine Model HSM originally developed for the Unix environment was recoded for the personal computer. This recode included code improvements and bug fixes, as well as the development of a graphical interface for creating simulations. The HSM can be used to predict the forces and motions of a human spinal column. The vertebrae are modeled with rigid bodies while hydrodynamic elements model the intevertebral discs. A full set of ligamenteous and active muscular models is also incorporated. External accelerations can be applied to the system and the resulting response calculated. A novel method of calculating an initial equilibrium position was incorporated. Several simulations of frontal and vertical accelerations were conducted to demonstrate the utility of the software. Along with the HSM, a database of spinal element properties was created. This database can be separately used from the software to determine mass, material, and geometric properties of the spinal elements as derived from a variety of sources in the literature. This report details the operation of the GUI interface to create, edit, and run simulations.