Fall or shaken: traumatic brain injury in children caused by falls or abuse at home - a review on biomechanics and diagnosis.

In cases of traumatic brain injuries in children it may be difficult to differentiate between physical abuse and accidental occurrence. This review will shed light on discriminating epidemiological as well as biomechanical data, morphological findings, and clinical features. As a basic principle, simple injuries are caused by simple mechanisms like falls whereas life-threatening injuries should be attributed to abuse until proven otherwise. Implausibilities between reported events and mechanisms by caregivers as well as more than one explanation of injury indicate suspicion of child abuse. From reviewing the literature, it can be stated that falls from less than 1.5 m lead only in few cases to severe brain injuries. Children who experienced a fall at home seldom exhibit fractures of the skull but just minor intracranial injuries without neurological deficits. Regarding biomechanical aspects, multiple or complex skull fractures, depression fractures, additional fractures of the body, and intracranial hemorrhages as a consequence of an impact are the most important findings in child abuse. Moreover, additional specific morphological criteria give evidence of clinical and/or post-mortem diagnosis of the shaken baby syndrome. These include subdural hemorrhage and laceration of the brain and retinal bleeding, epidural hemorrhage of the cervical cord, gripping marks (bruises) on chest and/or shoulders, and tearing injuries of the throat and neck muscles. Post-mortem signs of recurrent shaken baby syndrome are indicated by iron-positive cells or microglial cells in neuronal or retinal tissue. A clinical diagnosis will be dependent on the one hand on the exclusion of coagulation diseases, on the other hand on the demonstration of a subdural hemorrhage by means of neuroimaging techniques, i.e., CT and MRI, as well as retinal hemorrhage. The shaken baby syndrome will usually be observed within the first year of life. The doctor has to manifest his diagnosis to the caregivers and - before informing the caregivers - he must be sure of his diagnosis.