Fracture or a normal ossification center?

This is a common question heard when viewing an xray of a pediatric elbow. How do you remember the timing of normal ossification centers? FYI, the xray images above are normal and have no fractures.

Trick of the Trade

The mnemonic CRITOE 1-3-5-7-9-11

  • Age 1 year: Capitellum
  • Age 3 years: Radial head
  • Age 5 years: Internal (medial) epicondyle
  • Age 7 years: Trochlea
  • Age 9 years: Olecranon
  • Age 11 years: External (lateral) epicondyle

This great video is from a relatively new YouTube channel that I stumbled upon called “Radiology Channel“, which is a project featuring short polished presentations by Dr Andrew Dixon, Dr Frank Gaillard and Dr Jeremy Jones.

Michelle Lin, MD
ALiEM Founder and CEO
Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco
Michelle Lin, MD


Professor of Emerg Med at UCSF-Zuckerberg SF General. ALiEM Founder @aliemteam #PostitPearls at Bio:
Michelle Lin, MD