Do you have ANY idea what caused this? Did the screw break or did it just fall out?
It might be difficult to do anything about this, since I doubt that your surgeon will admit to any "wrongdoing" if that's the cause. If it just "fell out" I would have to assume that it wasn't put in properly -- but you know what happens when you assume!
You could ask the surgeon for your records -- especially if you're going to see another surgeon. But chances are it won't say anything about the incident -- or he'll remove it.
Wish I could help. I hope you heal quickly! Best of luck & God bless. Hugs, Lee