Primary Blast Injury

Primary Blast Injury

A teenager presents to the Los Angeles pediatric emergency department on July 4th complaining of decreased hearing and pain in his left ear. Prior to the presentation, the youth and his friends had been playing with fireworks when a large firecracker detonated close to the left side of his head. Examination of the left ear with the Wispr Digital Otoscope reveals this image.

The teenager has suffered a primary blast injury to his eardrum.

There is a significant disruption of the tympanic membrane (eardrum) is circled in this image.

PPT TM Rupture


Blast injuries are classified as follows;

  • Primary – from the pressurization wave of the blast. Primary injuries present to the lung, eye, eardrum (as in this case), abdomen and brain.
  • Secondary – from flying debris. Secondary injuries can occur anywhere. An example would be penetrating injury from metal that was surrounding a bomb. The individuals that died at the Boston Marathon bombing suffered secondary blast injuries.
  • Tertiary – from the individual being thrown by the blast. Tertiary injuries present as orthopedic or traumatic brain injuries.
  • Quaternary – explosion related. Examples of quaternary injuries include burns, crush injuries, asthma exacerbations from dust storms, and radiation exposure.

Minor tympanic membrane ruptures generally heal on their own. In this case, the damage is significant, clearly affecting where the malleus attaches to the tympanic membrane. This patient needs an urgent consultation with otolaryngology (ENT). The decision to start medication would be guided by a stat consult with ENT but is generally not indicated. The patient should be told to avoid any moisture in the ear until evaluated by ENT. He will likely need surgical intervention to repair the extensive damage to both the tympanic membrane and the middle ear structures.

WiscMed thanks Dr. Patricia Padlipsky of Harbor-UCLA for contributing this interesting image.