I broke my leg (broke the lower bone in half and pierced my skin) riding a motorbike. You must love us motorbike riders. Fortunately I was wearing full protective gear, but experienced the shortcomings of ankle high boots rather than full boots.
I've had a couple bad ass injuries like that. One guy ran his bike into a tree. Damn near amputated his lower leg just from the impact. I believe he lost it later in surgery. He didn't have on full height boots. Ride safe my friend.