Shaken Baby Syndrome (SBS) is the name given to the collection of signs and symptoms resulting from violently shaking an infant, with or without impact to the head. Other names have been used to describe these signs and symptoms including Abusive Head Trauma, Shaken Impact Syndrome, Inflicted Head Trauma and Intentional Traumatic Brain Injury.
During a shaking episode, an infant’s head moves back and forth in a figure of eight motion. The rapid acceleration-deceleration of the brain causes the brain and skull to move at different speeds in different locations. As the shaking continues, veins begin to break causing bleeding in and around the brain and eyes. Injuries to the bones may occur from pressure on the ribs. Factors that contribute to an infant’s vulnerability include weak neck muscles, a relatively large head size and the fact that the person doing the shaking is much more powerful than the infant.