Method to predict spinal injuries

A 3D animated mathematical model of the human spine developed by the Defence Science and Technology Organisation (DSTO) promises to be the most accurate predictor yet of injury to the spine and associated neuro-muscular tissues.

Challenging existing theories of biomechanics, the Human Biodynamics Engine (HBE) model will radically improve the ability to anticipate the point in time and specific location of potential injuries. This will have many applications including the design of wearable and carried loads, safety assessment of workplace activities, and as a possible alternative to million-dollar crash test dummies.

The model was developed by DSTO scientists Dr Vlad Ivancevic to examine the implications of head mounted loads such as night vision goggles on the performance and wellbeing of Australian Defence Force (ADF) soldiers.

The model has been incorporated into its first application, a standalone Windows package known as the 'Full Spine Simulator', which represents all 25 movable joints of the spine with three rotations and three limited translations at every joint.

"The spinal column is not columnar at all," says Dr Ivancevic. "It is a chain of 25 joints each with six degrees of freedom - and the injury is somewhere at one or more of these. It is not 'in the spine'. With this model we can predict where the injury will occur."

The model includes automatic stabilising movements driven by muscular excitation and contraction dynamics, spinal reflexes and cerebellum (lower brain) control. It can be placed in a dynamic environment with various parameters set to represent body size, strength and endurance.

External factors can also be set, including initial posture, vibration and cyclic motion. Impacts such as a car crash, ejection or hard landing can also be entered. Load parameters such as the mass and position of additional loads can then be added to the body model.

This work is now being used by the Defence Materiel Organisation (DMO) in its approach to equipment selection and operational guidelines while the HBE has also generated strong interest with Australia's international defence partners in USA, UK, Canada and New Zealand.