Shaken baby syndrome

Definition

Shaken baby syndrome is a severe form of head injury caused by violently shaking an infant or child.

Alternative Names

Considerations

Shaken baby syndrome can occur from as little as 5 seconds of shaking.

Such shaking usually takes place when the infant is crying inconsolably and the frustrated caregiver loses control. The violent shaking may result in severe injuries to the infant, permanent brain damage, or death.

Injuries are most likely to happen when there is both acceleration (from shaking) and deceleration (from the head hitting something). Even hitting a soft object, such as a mattress or pillow, may be enough to injure newborns and small infants. The result is a type of whiplash, similar to that seen in some auto accidents. A number of factors make infants highly vulnerable to such forces. For example, children's brains are softer, their neck muscles and ligaments are weak and not fully developed, and their heads are large and heavy in proportion to their bodies.

When an infant or toddler is shaken, the brain bounces back and forth against the skull. This can cause bruising of the brain (cerebral contusion), swelling, pressure, and bleeding in the brain.

The large veins along the outside of the brain may tear, leading to further bleeding, swelling, and increased pressure. This can easily cause permanent brain damage or death.

Shaking an infant or small child may cause other injuries, such as damage to the neck, spine, and eyes. Eye damage is very common and may result in loss of vision (retinal hemorrhage).

Shaken baby injuries usually occur in children younger than 2 years old but may be seen in children up to the age of 5.

Causes

In most cases, an angry parent or caregiver shakes the baby to punish or quiet the child. Many times the caregiver did not intend to harm the baby. Nevertheless, it is a form of child abuse.

Shaken baby syndrome does not result from gentle bouncing, playful swinging or tossing the child in the air, or jogging with the child. It also is very unlikely to occur from accidents like falling off chairs or down stairs, or accidentally being dropped from a caregiver's arms. Short falls may cause other types of head injuries, although these are often minor.