An impact is any form of blunt force trauma, which can easily cause a compound fracture.
There are many ways that an impact can occur with or without a fall. For example, if you are to fall and you should hit your head or body on something on the way down – perhaps on a table or a wall – then this can easily result in that kind of fracture.
Similarly, an impact might mean that something falls on you. This could be debris from a building site or a cliffside, or it could be a falling tree branch. Either way, this impact from above can cause trauma of the head, shoulder, back, or limbs. It’s also possible for the trauma of this kind to occur due to thrown objects – which could be intentional or otherwise. Projectiles can also be the result of weapons or even explosions.