When Levi was six months old, he was hit by a van. He fractured his upper left foreleg by a joint, and we had to have 2 pins put in.
It's really important to follow the vet's instructions after your dog comes home. Levi was strictly crate confined for 2 months. That's going to be really tough with a young dog, but it's doable. You can carry him outside and set him down so he can pee and poop, but no hopping around. He'll probably come home with a cast looking thing on. This
needs to be kept clean (we kept tube socks over Levi's) and DRY (plastic shopping bag over it anytime it's raining or dewy out).
Also, with such a young dog, it is VERY hard to keep them from jumping around. Being so hyper, they can very easily rebreak their leg, or break the pin. That being said, I would really recommend asking your vet for some sedatives if you have a hyper dog. It really sucks to see your puppy medicated like that, but honestly, if we hadn't done that for Levi, I'm afraid he would have hurt that leg again. We tried it for the first couple weeks w/out anything, and he was moving around so much trying to get out of his crate, he would yelp every once in awhile because he'd hurt himself. Sedatives really helped keep him comfortable (because he was sleeping so much he never hurt the leg), and helped his leg heal better.
The only time Levi was allowed out of his crate was late at night, when it was just me and Josh up, so he wouldn't have any distractions or things to get him excited. We would lay on the floor with him and watch TV. But that's all you can do with him... and you have to be really diligent about it.
Levi had 2 pins put in. One that came out about 2 months after his initial surgery, and one that stayed in permanently.
Now for the good news. Levi recovered perfectly. We had a really good orthopedic surgeon, who did an excellent job. And we watched him like hawks during his recovery.
So if you just follow your vets instructions (and consider those sedatives... honestly) very closely, you should be fine. And just to prove that your pup has an excellent chance at a good recovery... here's Levi.
You can see his scar on the front leg closest to the camera. That's the only way you'd ever know he had surgery.
If you have ANY other questions, PM me or email me, since I went through pretty much the same thing. Good luck.