Capitellum |
1 year |
Radial head |
3 years |
Internal (medial) epicondyle |
5 years |
Trochlear |
7 years |
Olecranon |
9 years |
Lateral (External) |
11 years |
There are six ossification centres in the elbow of a developing child and they occur in a fixed order at sequential times up to the age of 13 years, although these times are variable.
It is the presence of these centres that make paediatric elbow x-rays notoriously difficult to interpret. Knowledge of these ossification centres and the age at which they appear will assist the observer in identifying whether a fracture is present or not.
A well known helpful pneumonic for this is CRITOL or CRITOE.
Note that these ages vary but a broad guide of 1,3,5,7,9 and 11 years is easy to remember.