Leg injury from Nose-it / Treat toy?

So my horse has a bump on his leg and is slightly lame this morning. I lunged him and rode him last night and he was fine. While I was trying to think of what could of caused his leg injury, I remembered I gave him his Nose-it treat toy last night before I left. He gets a little crazy with it, pawing it, hitting it with his foot. Is it possible this could cause his leg injury?? has this happened to anyone?

Horses can injure themselves on anything. This injury sounds like a splint perhaps?