Deformity is a medical term for, well, being deformed. It’s when a part of the anatomy isn’t formed the way it’s supposed to be. It can be a bone that’s bent in the wrong place or a foot that’s twisted at an odd angle. It can also be as simple as a grossly swollen ankle.
Swelling is a really common form of deformity and it is from blood or other fluid accumulating at the site of the injury.
Swelling isn’t a great indicator of a fracture because it comes from the soft tissues—that pesky flesh and blood—that can’t be “broken.”