← Radiology signsAsk Alera

Football sign

PaediatricRadiograph

A large oval lucency fills the abdomen, outlined by the falciform ligament running like the laces of an American football.

What it means

Massive pneumoperitoneum, classically in a neonate with a perforated viscus.

Mechanism

A very large volume of free intraperitoneal gas distends the peritoneal cavity and silhouettes the falciform ligament centrally.

Associated conditions

  • Necrotising enterocolitis with perforation
  • Spontaneous gastric perforation
  • Perforated viscus in neonates
  • Massive pneumoperitoneum

Pearls

  • It signals a surgical emergency in the neonate.
  • The falciform ligament forms the football's central seam.

References

  • Radiopaedia: Football sign (pneumoperitoneum)

For educational use only. This dictionary is a study aid and reference, not a diagnostic tool, and must not be used to guide clinical decisions or patient care. Imaging appearances vary; always correlate with the full clinical picture and confirm with a qualified radiologist.