Neonatal Injuries in Child Abuse 

Child abuse is often misdiagnosed and underrecognized by physicians and caregivers. Child abuse occurs in many forms and is best defined as purposeful infliction of physical or emotional harm, sexual exploitation, and/or neglect of basic needs (eg, nutrition, education, medical care). Child abuse is an important cause of death in children. Among child abuse fatalities, head injury is the leading cause of death in infancy.

Shaken baby syndrome (SBS) is of particular interest to the neurologist, as it affects the nervous system. Shaken baby syndrome may cause long-term sequelae in the developing nervous system, and the effects may even be lethal. See the image below.

In 1946, Caffey reported a series of patients with multiple fractures and chronic subdural hematoma, which fit the profile of what is now defined as shaken baby syndrome.^[1] Kempe et al coined the term battered child syndrome.^[2] In 1967, Gilkes and Mann first reported the funduscopic findings of battered babies.^[3] In 1972, Caffey wrote about the syndrome of shaken infants. His report brought attention to this form of child abuse.^[4]

Anatomic features make infants especially prone to neurologic injury from excessive shaking or trauma. Infants have a large head compared with their body size, and the cervical paraspinal muscles are weak. (This accounts for head lag observed during the first month of life.) The infant brain has a higher water content than that of the adult brain, and it is incompletely myelinated. The subarachnoid spaces are also larger in infants than in adults, given the small size of their brains.

When the infant is shaken, movement of the immature brain in relation to the skull and the poor muscle tone in the neck cause the bridging vessels to tear, resulting in the classic finding of a subdural hematoma. Retinal hemorrhages are produced when venous congestion causes rupture of the retinal vasculature. Therefore, shaken baby syndrome is defined by subdural hemorrhage and retinal hemorrhage. One additional feature is occult fractures, particularly of ribs and long bone metaphyses.

The mechanism by which brain damage occurs is controversial. Traditionally, shearing forces from direct trauma were believed to cause axonal damage. Geddes et al suggested hypoxia-ischemia as the mechanism rather than axonal injury that is seen in older children and adults with lethal head trauma.^{[5, 6]} They also thought that acceleration and deceleration forces may damage the neuraxis to cause apnea, with consequent ischemia and cerebral edema.

Biomechanical studies of infant trauma injuries have shown that the magnitude of angular deceleration is 50 times greater when the infant's head strikes a surface than when he or she is only shaken. This force is distinct from those of other accidental traumas that occur in infants. This evidence suggests that the term shaking-impact syndrome is more accurate than shaken baby syndrome.

Frequency

United States

Approximately 43.1 of every 1000 American children are mistreated. In 2009, 3.3 million cases of child abuse and neglect were reported. Of these, 331,500 cases were substantiated. In the first year of life, accidental injury occurs more often than intentional injury. The incidence of trauma in children younger than 12 months is approximately 20.6 cases per 1000 children per year.^[7]

International

Good statistical data are not available.

Mortality/Morbidity

Abuse and neglect account for 5-14% of all deaths of children. In 2009 in the United States, 1770 fatalities from child abuse were reported, and 46.2% involved infants younger than 12 months. In Missouri, substantiated fatalities in 2009 included 33 children; 30 of these children (91%) who died from inflicted abuse or neglect at the hands of a parent or caregiver were aged 4 years or younger. Of those, 14 (47%) were infants younger than 1 year.^[8] Shaken baby syndrome is reported to be the leading cause of death in children younger than 4 years.

In children younger than 1 year, homicide is the leading cause of death. This is the only cause of death in children that is increasing in frequency.

Of the 33 Missouri children who died at the hand of a parent or caregiver in 2009, 17 (52%) were victims of abusive head trauma.^[8]

Sex

• Boys are affected more often than girls.
• The perpetrator is usually alone with the victim.

  • Men are the abusers in 90% of cases. The abuser is usually the biologic father or, in some cases, the mother's boyfriend.
  • The most common female attacker is a babysitter.
  • According to a Philadelphia-based study, 1 in 7 mothers who were abused as children admitted to using corporal punishment on their children.^[9]

Age

• In 2009, 3.3 million cases of child abuse and neglect were reported. Of these, 331,500 cases were substantiated. About 20.282% of the affected children were younger than 3 years, and 20.6% were younger than 1 year.^[7]
• The typical abused child is younger than 6 months.