His father, who twice reached the Pro Bowl as the New Orleans Saints quarterback in the 1970s, told ESPN Radio: "Certainly there was a time there we were concerned if he would play at all, and I think the big thing, we're all elated and happy for Peyton because he wanted to play some more and the doctors cleared him.
"Over a year's time there, one surgery after the other, as his parents, Olivia and I, we kind of quit thinking about football. We were just worried about Peyton's health and getting this thing straightened out. He finally had the fusion, they said it worked. Four different doctors cleared him to go back and play. They said he can go play.
"We didn't know how he could play at that position. I remember when he first started throwing, I mean, it was a 10-yard lob and you just don't know. He loves to play the game, and he feels really grateful that he's getting to play some more."
The Broncos will face Eli Manning's New York Giants next weekend.