Biomechanical Response of the Bovine Pia-Arachnoid Complex to Tensile Loading at Varying Strain Rates 2006-22-0025
The pia-arachnoid complex (PAC) covering the brain plays an
important role in the mechanical response of the brain due to
impact or inertial loading. However, the mechanical properties of
the pia-arachnoid complex and its influence on the overall response
of the brain have not been well characterized. Consequently, finite
element (FE) brain models have tended to oversimplify the response
of the pia-arachnoid complex, possibly resulting in a loss of
accuracy in the model predictions.
The aim of this study was to determine, experimentally, the
material properties of the pia-arachnoid complex under quasi-static
and dynamic loading conditions. Specimens of the pia-arachnoid
complex were obtained from the parietal and temporal regions of
freshly slaughtered bovine subjects with the specimen orientation
recorded. Single-stroke, uniaxial quasi-static and dynamic tensile
experiments were performed at strain-rates of 0.05, 0.5, 5 and 100
s-1 (n = 10 for each strain rate group). Directional
differences of the pia-arachnoid complex were also investigated.
Results from this study revealed the pia-arachnoid complex was
rate-dependent and isotropic, suggesting that the pia-arachnoid
complex can provide omnidirectional support and load bearing to the
adjacent brain tissue during an impact.