A CT scan revealed that a woman's abdominal pain was caused by a green plastic cake decoration. (Credit: The New England Journal of Medicine)

A 72-year-old woman learned the hard way that not all cake decorations are edible.

The woman, who has not been named, went to the emergency room after enduring three days of abdominal pain, according to a case study published in the New England Journal of Medicine. What doctors found - and eventually removed - was an ax-shaped cake decoration from the Christmas cake she'd eaten the week before.

The green plastic decoration was 2 centimeters long and had perforated her small intestine. Doctors repaired the damage, and the woman went home 10 days after surgery.