Elmo has never had any of his limbs broken so I wouldn't know exactly but any complicated surgeries he's had so far cost around $500~$600 (CAN) total. I remember IV and anesthesia was about $120, blood test $80 etc. The only thing he's ever broken was his molar, I think he was chewing on a bone too hard so he needed a dental surgery.
It sounds like your dog won't need a surgery though???
Hope everything will work out for you and your doggie Ralphy