Elbow ossification

A.Prof Frank Gaillard et al.

Elbow ossification occurs at the six elbow ossification centers in a reproducible order. Being familiar with the order of ossification of the elbow is important in not mistaking an epicodylar fracture for a normal ossification center. 

Appearance

Order

The order of appearances of the elbow ossification centers is highly reliable and in most individuals, is consistent: capitellum, radial head, internal epicondyle, trochlea, olecranon and external epicondyle.

The order of "I" and "T" are most important to remember; the trochlea ossification center should not appear before the internal (medial) epicondyle ossification center. If you can see a trochlea but no internal epicondyle, then you need to look very hard for the avulsed ossification center. 

Age

Two counting methods are taught to help remember the ages at which the ossification centers appear: 1-3-5-7-9-11 (simple) and 1-5-7-10-10-11 (more accurate).

Therefore, if the trochlear center is present, but there is no medial epicondyle then you are most likely looking at a medial epicondylar fracture where the ossification center has been avulsed and displaced. This is extremely important since these injuries should be seen by an orthopedic surgeon and internally fixed.

Video tutorial

 

Anatomy: Upper limb
Share article

Article information

rID: 1263
Section: Anatomy
Synonyms or Alternate Spellings:

Support Radiopaedia and see fewer ads

Cases and figures

  • Age 2: C
    Drag here to reorder.
  • Age 4: CR
    Drag here to reorder.
  • Age 5: CRI
    Drag here to reorder.
  • Age 9: CRITO
    Drag here to reorder.
  • Age 11: CRITOE
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.