New bone cells grow to join up the broken pieces. One of the most exciting areas of biomedical materials science is making “bone scaffolds” – these are structures that encourage new bone cells to grow and can be used to produce new bones, not just mend broken ones.
The boys are right, but Will, bones are amazing at trying to heal really fast. Sometimes, with bad breaks, or breaks where the person doesn’t realise it’s broken, the ones start to heal but in the wrong place, so they are jagged, and (AWFUL THOUGHT!) they need to be re-broken in order to be reset correctly and put into a cast.
Makes me shiver thinking about it! As it one break isn’t bad enough, having a doctor do it all over again…!