Shaken Baby Syndrome (SBS) is the name given to the collection of signs and symptoms resulting from violently shaking an infant, with or without impact to the head.  In Canada the Public Health Agency of Canada’s Joint Statement on Shaken Baby Syndrome (SBS)

is now using the term Traumatic Head Injury by Child Maltreatment (THI- CM) to reflect current language used by health professionals and aids to separate the diagnosis (traumatic head injury) from opinion on the cause of injury (child maltreatment).

Definition: THI-CM is defined broadly to include traumatic injury to the head (skull and/or brain and/or intracranial structures), which may also be accompanied by injuryto the face, scalp, eye, neck or spine, as a result of the external application of force from child maltreatment.  

Other names have been used to describe these signs and symptoms including Abusive Head Trauma, Shaken Impact Syndrome, Inflicted Head Trauma, and Intentional Traumatic Brain Injury. 

During a shaking episode, an infant’s head moves back and forth in a figure of eight motion.  The rapid acceleration-deceleration of the brain causes the brain and skull to move at different speeds in different locations.  As the shaking continues, veins begin to break causing bleeding in and around the brain and eyes.  Injuries to the bones may occur from pressure on the ribs.  Factors that contribute to an infant’s vulnerability include weak neck muscles, a relatively large head size and the fact that the person doing the shaking is much more powerful than the infant. 


Permanent Brain Damage


Physical abuse is the leading cause of serious head injury in children under the age of two.  Approximately 20% to 25% of babies subjected to shaking die (Keenan HT, et al., 2003; King WJ, et al., 2003).  Of those who survive, as many as 80% have permanent brain damage (King WJ, et al., 2003).

The financial burden of one survivor for initial and lifelong care can range between $300,000 to over $1,000,000.  However, the impact of these preventable deaths far exceeds the financial consequences. 

The most reliable estimate of incidence in North America comes from North Carolina, USA, where there was an average of 29.7 cases per 100,000 person-years for children under one year of age (Keenan HT, et al., 2003).  In an Edinburgh study, a similar incidence of 24/100,000 infants was reported (Barlow KM & Minns RA, 2000).

Using the KIDS database in the USA, incidences of 27.5, 27.5 and 32.2 hospitalized cases per 100,000 births were reported for 1997, 2000 and 2003 respectively (Ellingson KD, et al., 2008).

It is now clear that crying, especially inconsolable crying, is the most common trigger for shaking and other forms of infant abuse (Barr RG, Trent RB, & Cross J, 2006; Lee C & Barr RG, et al., 2007).  Education about this normal and often frustrating period may prevent SBS and other physical infant abuse cases. 

Financial Burden Range



What are the Symptoms?

Non-Specific Symptoms

  • Irritability
  • Tiredness
  • Loss of Appetite
  • Poor Feeding
  • Vomiting
  • Poor Sucking and Swallowing
  • Lack of Smiling or Vocalizing
  • Poor Muscle Tone
  • Dilated/Unequal Pupil Size

Severe Symptoms

  • Buling and/or Spongy Forehead
  • Rigidity
  • Seizures
  • Loss of Consciousness
  • Difficulty Breathing
  • Death