Centers of Ossification

 

Age of appearance in girls CRITOE

Center Simple Accurate
Capitellum 1 1
Radial head 3 5
Internal epicondyle 5 7
Trochlea 7

10

Olecranon 9 10
External epicondyle 11 11

Boys on average 2 years later in every center except capitellum

 

Patel et al Paediatr Radiol 2009

- 412 xrays aged 2 - 17

- all centers both appear and fuse early in girls

- capitellum is the only exception

- order is consistent

- age is somewhat variable

 

1 year old5 female

1 year old male: C                                             5 year old female: CR

 

8 year old male8 M 2

8 year old male: CRIT

 

11M 11 M 2

11 year old male: CRITOE

 

Closure

 

Capitellum / trochlea / lateral epicondyle

- fuse together age 14

- fuses to metaphysis age 15

 

Medial epicondyle fuses age 15 girls and 17 in boys