Correct identification of the fibula can be tricky. These notes by slipstreamborne might provide some help in case of confusion:
Ah, the fibula. Wonkiest of the long bones. I could never side the fuckers without extensive consultation of my osteo notes or keep the proximal and distal ends straight until a TA of mine showed me this trick, which has the awesome benefit of working both with whole fibulae and any shaft fragment (!!!!!!!) that includes part of the distal third or so of the shaft. AND you can do it by touch, which is a double bonus if you’re more tactile and shape oriented in your siding like me. AND IT WORKS UPSIDE DOWN, so you’re not completely fucked if you can’t figure out which end is up.
Okay, see that diagonal line there on the lateral view on the right? And how it defines a roughly triangular surface of bone just proximal to the distal end? That is the triangular subcutaneous area of the fibula and it is your new best friend.
(See T.D. White knows what I’m talking about.)
The key point here is that this very rough right triangle tapers towards the same direction that the bone is from. Just follow it with your eyes or your fingers, base to top. This one is a right, so it points up and to the right.
And if you have the bone upside down, you can still follow that diagonal line from the base to the top and it will point towards the side the bone is from.
So even if you have a professor who likes to hide bits of bones in boxes and make you identify and side them without looking, FEAR THE FIBULA NOT! Go forth and side it like a champ.