Ossification begins in the shaft of the humerus, ulna and radius in the 9th week of fetal development - this ossification is visible at birth on a radiograph.

Secondary ossification centres make the remaining architecture of the elbow, which in appear in the following sequence (CRITOE):

C - capitellum 1-2 years

R - radial head 3 - 6 years

I - internal (medial) epicondyle 4 years

T - trochlea 8 years

O - olecranon 9 years

E - external (lateral) epicondyle 10 years

There is considerable variability in the specific time of appearance of these ossification centres, appearing earlier in females than in males, on average.

All these centres completely fuse in the mid to late teenage years.