Imaging (Ossification Centres)
| 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.