Diagnosis of Shaken Baby Syndrome
A classic triad most commonly seen consists of single or multiple subdural hematomas (localized bleeding outside of the brain substance), diffuse and multi-depth retinal hemorrhages, and diffuse brain injury without a reasonable explanation for such severe (and often repeated) trauma. Several agencies recommend that the term shaken baby syndrome be replaced with abusive head trauma. Such a change broadens the various mechanisms of injury commonly seen besides shaking. Blunt head trauma is commonly seen in addition to shaking. Common mechanisms of direct blows to the head include punching the infant, hitting the head or face with a hard object (for example, wooden spoon), or slamming the infant's head against the wall or floor.

Because children may not present for evaluation with evidence of trauma (bruising, lacerations, etc.), a high index of suspicion must be maintained by those responsible for evaluating such children. Missed cases of shaken baby syndrome may be incorrectly diagnosed as viral infection (especially gastroenteritis, in which children will be lethargic and have a history of repeated vomiting) or accidental head injury (for example, fell while being carried by a parent, rolled off of a bed, or abuse by an older sibling). Multiple studies have demonstrated that, while the duration of shaking necessary to inflict such substantial trauma may be accomplished in 15-20 seconds, adult strength is necessary to inflict such damage (for example, parental perpetrators may attempt to blame a childhood sibling as the culprit). Likewise, rolling off of a bed or couch or being held during a parental fall are extremely unlikely to cause such injury. Documentation of old skeletal fractures, burns (commonly cigarette or hot water immersion), healing bruises, or ligature injury may be discovered during an investigation.