This paper presents a new analysis of the physics of closed head injury following brief, intense acceleration of the head. It focuses upon the buoyancy of the brain in cerebrospinal fluid, which protects against damage, the propagation of strain waves through the brain substance, which causes damage, and the concentration of strain in critical anatomic regions, which magnifies damage. Numerical methods are used to create animations or "movies" of brain motion and deformation. Initially a 1 cm gap filled with cerebrospinal fluid (CSF) separates the brain from the skull. Whole head acceleration induces artificial gravity within the skull. The brain accelerates because its density differs slightly from that of CSF, strikes the inner aspect of the skull, and undergoes viscoelastic deformation. The computed pattern of brain motion correlates well with published high-speed photographic studies. The sites of greatest deformation correlate with sites of greatest pathological damage. This fresh biomechanical analysis allows one to visualize events within the skull during closed head injury and may inspire new approaches to prevention and treatment.
biomechanics, concussion, diffuse axonal injury, head injury, shear, strain
Date of this Version
Babbs, Charles F., "Brain motion and deformation during closed head injury in the presence of cerebrospinal fluid" (2004). Weldon School of Biomedical Engineering Faculty Publications. Paper 41.