Oh No! Kids' elbows.

People often get confused about which bit of a child's elbow is supposed to have appeared (ossified) and which bits are supposed to be invisible at any given age.  What do you make of this 13 year old's Xray?

This child should (at 13) have ALL of their ossification centres visible.  If you look for each of them in turn you see that the internal epicondyle (medial/ulnar) is missing.  Look harder still and you see it superimposed over the trochlear, in the joint.

This link takes you to a brilliant talk through the ossification of kids' elbows.  If you want the shortened version watch from 1:20 to 3:25.  120 seconds of pure gold radiology learning.

Short version?
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