Shaken Baby Syndrome

Historical Background and Pathogenesis

This specific traumatic complex was first described by pediatric radiologist John Caffey in 1946. He drew attention to an atypical combination of chronic subdural hematomas (SDH) and long bone fractures in infants with no underlying or genetic predispositions. Nearly three decades later, in 1974, Caffey definitively linked these injuries to the act of forceful infant shaking, adding severe brain damage, retinal hemorrhages (retinal haemorrhage), and subsequent mental retardation to the clinical picture.

Modern biomechanical studies have significantly refined the injury mechanism. It has been proven that intense shaking alone (unless accompanied by significant neck trauma) is unable to generate the classic triad of symptoms: subdural hematoma, retinal hemorrhage, and encephalopathy. The trauma is driven by the colossal disparity in physical size and body mass between the defenseless infant and the perpetrator.

Evolution of Terminology and Epidemiology

Since biomechanical studies proved the critical importance of a concomitant impact in forming the full clinical picture, the initial name of the pathology underwent changes. Clinicians first began using the term "shaken baby-impact syndrome" (shaken baby-impact syndrome).

Currently, pediatrics and radiology use an even broader term — abusive head trauma (abusive head trauma). This concept more accurately reflects the essence of the problem, as it encompasses the entire spectrum of central nervous system pathologies caused by any form of forceful shaking or impact.

This pathology has strict age boundaries. It is limited to children under 2–3 years of age, with the vast majority of severe cases and the peak of diagnoses occurring in infants under 6 months old.

Imaging Strategies and Radiography

The choice of an appropriate diagnostic imaging method at the slightest suspicion of abuse depends on the child's age, as well as the presence of thoracic, abdominal, or neurological symptoms. Physicians are guided by the strict criteria of the American College of Radiology (ACR) and the recommendations of the UK Royal College of Radiologists and Royal College of Paediatrics and Child Health (RCR-RCPCH).

• Golden Rule of Examination: A complete skeletal survey (skeletal survey) is recommended for absolutely all children under 2 years of age when abuse is suspected.
• Skull Radiography: This is a strictly mandatory procedure for identifying skull vault fractures. Notably, it is performed even if the patient has already undergone a brain CT scan.
• Cervical Spine Specifics: Radiographs may reveal pseudosubluxation (pseudosubluxation) of the C2 vertebra relative to C3. A hallmark feature is that an extension view radiograph in the same patient will demonstrate completely normal anterior alignment of the vertebrae.
• Older Children (2 to 5 years old): In this group, a full skeletal survey has a much lower diagnostic yield. Decisions are made on an individual basis, and targeted radiographs of specific areas of suspected trauma are ordered as an alternative.

Neuroimaging: The Role of CT, MRI, and Scintigraphy

Advanced neuroimaging modalities play a key role in detecting intracranial injuries and determining management strategies to save the child.

Brain CT: Indicated on an emergency basis for any infant under 1 year of age with signs of physical abuse. For older children, CT is indicated if signs of abuse are accompanied by encephalopathy, focal neurological deficits, or hemorrhagic retinopathy.

Urgent Brain MRI:

1. Absolute necessity if initial CT reveals a subdural hematoma or brain tissue injury.
2. Must be performed if the CT scan is normal but neurological deficits persist.
3. Serves as the most sensitive method on days 3–5 for detecting subarachnoid hemorrhages, cortical shearing injuries (cortical shearing injuries), and areas of hypoxic-ischemic damage.
4. Cervical spine imaging should also be considered during the MRI scan.

Bone Scintigraphy: A highly sensitive method useful when routine skeletal survey results are equivocal (equivocal), or when clinical suspicion of abuse remains very high despite a negative radiograph. Main limitation: the procedure must be performed exclusively in departments with proven experience in bone scanning specifically in infants.

Class and exam questions

What else to study on this topic

• Biochemical mechanisms of cortical shearing injuries in rotational trauma.
• Distinctive radiographic features of C2-C3 pseudosubluxation versus true spinal injury in infants.
• Algorithm for bone scintigraphy in infants: indications and technical limitations.
• Mechanisms of hypoxic-ischemic brain injury in shaken baby syndrome.

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.