Simulation of acute subdural hematoma and diffuse axonal injury in coronal head impact

Neuropsychology and clinical neuroscience of persistent post-concussive syndrome

“…Obviously, high speed impact head injuries are not a controlled experiment and likely involve more significant pressure and shear-strain forces than what are seen in sports concussion (Bradshaw et al, 2001;Zhang et al, 2006a). Regardless of these factors, the same brain regions as described earlier and as shown in Figures 1 and 2 are likely involved in all concussions, just a matter of degree.…”

Influence of angular acceleration–deceleration pulse shapes on regional brain strains

“…The 22 ms duration acceleration pulse was followed by 6 ms duration deceleration pulse, and the peak magnitude of deceleration was approximately six times peak acceleration, with 0 ms separating time interval (Meaney et al, 1990). More recently, in a series of studies conducted to investigate brain mechanics, physical model tests used a biphasic pulse with peak accelerations approximately six times peak decelerations with 90 ms separating time interval, and pulse durations of 4.5 and 20 ms for the acceleration and deceleration phases (Bradshaw et al, 2001;Ivarsson et al, 2002Ivarsson et al, , 2000. Finite element modeling studies have used continuous (separation time 0 ms) biphasic haversine pulses with identical peak amplitudes and 30 ms combined pulse duration (Zhang et al, 2001).…”

“…However, increasing angular accelerations at a greater rate with longer pulse durations resulted in acute subdural hematoma. Physical modeling studies have also identified different candidates to describe differing types of brain injuries, implying region-specific response of the human brain (Bradshaw et al, 2001). Because injuries from animal experiments are coupled with angular loading via parameters such as strain, it is important to know how the strain field changes with alterations in the loading profile.…”

Comparison of MADYMO and physical models for brain injury reconstruction

“…Using basic physical models of the human brain, Holbourn [11] demonstrated how rotational acceleration can cause diffuse strains in the brain tissue; as these are considered to be a primary cause of subdural heomatoma (SDH) and concussion. More recently Bradshaw et al [3] used a physical model of the human skull and brain to demonstrate the mechanisms of subdural hematoma and diffuse axonal injury, indicating that impact kinematics, and rotational acceleration in particular has a significant influence on the presence of these diffuse TBI injuries. This early work on brain injury using cadaver, animal, and basic physical models demonstrated that the continuum of brain injury can be traced back to impact induced motions [25].…”