Inflicted head injury in infants.

There is scant neuropathological information in the child abuse literature; even the best reviews include assumptions based on the findings of a few inadequate early studies. Our recent series of 53 fatal cases (Brain 124 (2001) 1290, 1299 [1,2]) demonstrated age-related patterns of brain injury and showed the substrate of severe encephalopathy in the infants to be hypoxic brain damage, not diffuse traumatic axonal injury ('DAI'), as had previously been thought. About one-third had craniocervical injuries, particularly in the brain stem, suggestive of stretch injury to the neuraxis. Our interpretation was that this finding implied a mechanism of injury--brain stem damage from stretch injury to the neck with resultant apnoea--that could account for the clinical scenario in many cases, and for which violence would not necessarily be required. Since publishing this study we have turned our attention to the subgroup of infants who die without objective signs of injury, such as skull fracture or impact, whose carers are accused of abuse, usually, "violent shaking", on the pathologic findings alone. Given the striking discrepancy that there often is in such cases between the relatively trivial findings in the brain and the accusations of violence, we have been looking at the pathogenesis of the typical intracranial bleeding. A histologic study of dura from 50 paediatric autopsies, none of whom had suffered a head injury, has led us to propose that the subdural and retinal bleeding in such cases may well have a physiological aetiology, rather than being caused directly by trauma.