Thanks everyone.
He is out of surgery and awake. They said he's doing very well and can see mobility in his leg which is a good sign. He experienced bouts of vomiting before an dafter the procedure, but they said it's not uncommon and are giving him something for it. We are not allowed to visit on the day of the surgery, so I won't be able to see him until we pick him up tomorrow.
They put a pin in his bone, that was able to be guided with a camera so the surgery wasn't too invasive.
He will need plenty of rest for 3-4 weeks as he heals. Which for him, who had the run of house (he was pretty much 99% potty trained), is going to be tough. Picking up a crate from a friend tonight to keep him in. It's going to be so sad to confine him to it
but it's for his own good so I'll just have to not feel guilty about it.
Thank you for your kinds words. I'll keep you updated when he comes home.