Abdominal trauma in children should garner an appropriate amount of respect and concern. The child’s abdominal wall, unfortunately, is not as protective of the internal structures compared to adults’ abdominal wall. Additionally, signs of trauma can be minimal or nonexistent. Sometimes, the history alone is enough to raise a red flag. One of those history features is the classic bike injury sustained when the bike handlebar strikes the upper abdomen. Let’s digest a quick (and delicious) morsel on Duodenal Hematoma in Children:

Duodenal Hematoma: Anatomy Matters

• Anatomic features that make children more susceptible to blunt abdominal trauma:
  • Less protective covering.
    • Thinner abdominal muscles and less fat.
  • Less protective ribs.
    • The compliant ribs do not dissipate force.
    • That transmitted force now is absorbed by the underlying organs and structures.
  • More exposed solid organs.
    • The diaphragm is more horizontal compared to older patients.
    • The liver and spleen are, thus, more anterior and less protected by rib cage.
• All abdominal organs are at risk for injury. (Maguire, 2013)
  • Solid Organs
    • Liver injury is the most commonly seen in hospitalized patients (64%).
      • Abuse is reported as being the 2nd or 3rd most common cause of hepatic injury in children, after MVCs.
    • Kidney (19% of hospitalizations)
  • Hollow Organs (12% of hospitalizations)
    • Duodenal hematoma, perforation, and transection have been documented.
    • Often present in delayed fashion: 
      • Both accidental trauma non-accidental trauma can lead to DELAYED presentations.
      • May take more than 24 hours to manifest its severity. [Alkan, 2012; Clendenon, 2004]

Duodenal Hematoma: Basics

• The duodenum is relatively protected given its retroperitoneal location.
  • Injuries to the duodenum are uncommon. [Sowrey, 2013]
  • <1% of traumas involved the pediatric duodenum. [Clendenon, 2004]
  • Unfortunately, historic data shows high mortality rates for those with duodenal injuries, although more recent data has lower mortality rates. [Clendenon, 2004]
  • Close proximity to other structures increases chance of concomitant injuries. [Sowrey, 2013]

• Duodenal injuries: Adults vs Children
  • Adults injure their duodenum via penetrating trauma most often.
  • Children most often experience duodenal injuries via blunt trauma.
    • Unfortunately, this blunt force is often encountered through abuse. [Clendenon, 2004]

• Difficult to diagnose:
  • Retroperitoneal location makes imaging less reliable.
    • Plain xrays will not show free air from duodenal perforations.
    • CT scans may show only subtle findings. [Kurkchubasche, 1997]
  • May lack external signs of trauma.
  • Delayed presentations make appreciation difficult.
    • Initial assessment following abdominal injury may under-represent the true injury.
    • Requires high index of suspicion.

• Duodenal hematoma can lead to a partial or complete bowel obstruction.

Duodenal Hematoma: Mechanisms

• Common blunt mechanism:
  • ABUSE
    • Numerous reports of duodenal injuries being related to non-accidental trauma. [Sowrey, 2013; Terreros, 2009; Gaines, 2004]
    • For younger children (< 5 years of age) abuse is the MOST COMMON mechanism of duodenal injury.[Sowrey, 2013]
    • Abuse should be suspected in all cases of duodenal injury in children < 2 years of age unless due to a witnessed motor vehicle collision. [Sowrey, 2013]
  • Bicycle handlebars [Alkan, 2012]
    • Handlebars can lead to penetrating or blunt trauma.
  • Hockey sticks
  • Motor Vehicle Collisions and All-Terrain Vehicle crashes
  • Fall onto object or object crushing down onto abdomen
  • Sports-related impacts
  • Invasive procedures [Sahn, 2015]

• Crushing mechanism:
  • Mechanism is similar to the lap-belt complex injuries, but higher location on the abdomen.
  • Duodenum is crushed between the vertebral column and the handlebar.

Moral of the Morsel

• Bikes are fun… but their handlebars can be painful! Don’t overlook the history of blunt trauma to a child’s abdomen, even if the exam is not revealing.
• Be vigilant, but reasonable. Don’t CT ever child with a mild blunt force to the belly. GIVE GOOD ANTICIPATORY GUIDANCE and document that conversation.
• Be suspicious of injuries in the young! If you find a duodenal (or any) injury in a young child, consider non-accidental injury.

References