Shaken baby syndrome (SBS) is the hypothesis proposed by medical doctors that an infant can be shaken hard enough to cause a bleed on the brain (a subdural hematoma or hemorrhage) without any external trauma or impact. The problem with this hypothesis is that bioengineers could not confirm the hypothesis in the laboratory.
Dr. John Caffey, often credited with “discovering” shaken baby syndrome, hypothesized that by shaking a child, “[s]pecial lacerating stresses are thus applied to the cerebral bridging veins at the fixed sites of their attachment to the walls of the sagittal sinuses”[1] causing subdural hemorrhage. Dr. Norman Guthkelch, also credited with discovering the hypothesis, “postulated that whiplash forces caused subdural hematomas by tearing cortical bridging veins”.[2] Proponents further hypothesized that shaking caused immediate symptoms producing brain “injury referred to as shearing injury or diffuse axonal injury.”[3] Dr. Alex Levin, a leading advocate of the shaking hypothesis claimed that macular “retinoschisis has never been described in children due to any entity other than SBS so its presence is diagnostic.”[4] Thus “the neuropathological triad of subdural and retinal haemorrhages and acute encephalopathy was termed the ‘shaken baby syndrome’ (SBS)”[5].
In 2001, the American Academy of Pediatrics declared the shaken baby syndrome hypothesis to be a “clearly definable form of child abuse”.[6] According to the American Academy of Pediatrics, the presence of subdural and/or retinal hemorrhage in a child under the age of one year created “a presumption of child abuse”[7]. In other words, in the context where “[e]xternally visible injuries are often absent”[8] abusive shaking should be presumed without more than the presence of subdural and/or retinal hemorrhage. That “[s]ubarachnoid and subdural hemorrhages should be appreciated as markers of brain displacement by angular force and the possibility of accompanying diffuse axonal injury”[9], was the position taken by shaking hypothesis proponents. In other words, in the presence of subdural or subarachnoid hemorrhage (the marker), traumatic brain injury can be inferred without actual evidence of trauma to the brain (the presumption).
In 2001, doubt about the validity of the shaken baby hypothesis was gathering momentum[10]. By 2009, the American Academy of Pediatrics admitted that, despite the fact that medical and scientific “advances have improved our understanding of the range of mechanisms that contribute to brain injury”, “controversy remains.”[11] There is no controversy that impact causes subdural hemorrhage and brain injury, the only “controversy” is whether shaking can. As a result of the doubt and controversy, the American Academy of Pediatrics recommended the use of the “term ‘abusive head trauma’ rather than a term that implies a single injury mechanism, such as shaken baby syndrome”. Since it is not controversial that impact causes subdural hemorrhage and brain injury, the shift in terminology away from shaken baby syndrome is a recognition of the controversy of the shaking mechanism in cases where there is minimal evidence of impact to the child. In less than a decade the American Academy of Pediatrics went from declaring the shaken baby hypothesis a “clearly definable form of child abuse” to a conceding the hypothesis to be a “controversy” and avoiding use of the term “shaken baby syndrome”.
[2] American Academy of Pediatrics, Committee on child abuse and neglect, Shaken baby syndrome: Rotational cranial injuries – technical report, Pediatrics, 2001 108, 1, 206–210.
[3] Case ME, Graham MA, Handy TC, Jentzen JM, Monteleone JA, for the National Association of Medical Examiners Ad Hoc Committee on Shaken Baby Syndrome. Position paper on fatal abusive head injuries in infants and young children. Am ] Forensic Med Pathol 2001 ;22: 112-122.
[4] Levin AV. Retinal haemorrhage and child abuse. In: David TJ, editor. Recent advances in paediatrics, No. 18. London: Churchill Livingstone, 2000:151–219.
[5] Finnie JW, Manavis J, Blumbergs PC, Diffuse neuronal perikaryal amyloid precursor protein immunoreactivity in an ovine model of non-accidental head injury (the shaken baby syndrome); Journal of Clinical Neuroscience 17 (2010) 237–240 citing American Academy of Pediatrics Committee on Child Abuse and Neglect. Shaken baby syndrome: inflicted cerebral trauma. Pediatrics 1993;92:872–5.
[6] American Academy of Pediatrics, Committee on child abuse and neglect, Shaken baby syndrome: Rotational cranial injuries – technical report, Pediatrics, 2001 108, 1, 206–210.
[7] Id.
[8] Id.
[9] Case ME, Graham MA, Handy TC, Jentzen JM, Monteleone JA, for the National Association of Medical Examiners Ad Hoc Committee on Shaken Baby Syndrome. Position paper on fatal abusive head injuries in infants and young children. Am ] Forensic Med Pathol 2001 ;22: 112-122.
[10] Although the shaken baby hypothesis had never been accepted in the bioengineering scientific community, prosecutors, child protection agencies and much of the medical community had accepted the hypothesis. (See Duhaime AC, Gennerelli TA, Thibault LE, Bruce DA, Margulies SS, Wiser R. The shaken baby syndrome. A clinical, pathological, and biomechanical study. J Neurosurg. 1987;66:409–415. The forces generated by shaking are “well below the injury range”; and Prange MT, Coates B, Duhaime A-C, Margulies SS: Anthropomorphic simulations of falls, shakes and inflicted impacts in infants. J Neurosurg 99:143-150, 2003. “In addition, there are no data showing that the [force] experienced during shaking … is sufficient to cause SDHs (SudDural Hemorrhages) or primary TAIs (Traumatic Axonal Injuries) in an infant.” Perhaps the precipitating event of the public awareness and debate about the validity of the hypothesis was the 1997 trial of Louise Woodward, a British nanny accused of shaking young Matthew Eappen. Although Louise Woodward was convicted by a jury, the Judge’s lenient sentence led to a firestorm of public criticism by the proponents of the shaken baby hypothesis of any doubt about the hypothesis.
[11] Christian CW, Block R Committee of Child Abuse and Neglect, American Academy of Pediatrics: Abusive head trauma in infants and children. Pediatrics 2009; 123:1409-1411.