How has medical understanding of ‘shaken baby syndrome’ evolved?

An Ontario mother's acquittal in her infant son's death marks a shift in the medical understanding of what was once known as "shaken baby syndrome." The conviction, based on the alleged cause of death, was overturned as the expert evidence was deemed unreliable.

The term "shaken baby syndrome" has fallen out of favor in recent years, replaced by "traumatic head injury due to child maltreatment" (THI-CM) in Canada and "abusive head trauma" in the United States. This change reflects evolving medical knowledge and the need to distinguish between the injury itself and the cause of the injury.

Initially coined in the 1970s to describe infant abuse cases with internal brain and retinal bleeding, the syndrome was later found to be misclassified in many cases. A 2008 Ontario committee review of shaken-baby deaths questioned the validity of these diagnoses and pointed to other potential causes of death, such as strokes.

Revisions in 2020 by the Public Health Agency of Canada and the Canadian Paediatric Society to THI-CM better reflect current medical understanding. However, it's important to note that THI-CM is relatively uncommon, accounting for a small proportion of child abuse cases. The recommended terminology aims to clarify the diagnosis from potential opinions on the cause of injury.