Quarterback Peyton Manning #18 of the Indianapolis Colts signals to his team during the fourth quarter against the Denver Broncos in the AFC Wildcard playoff game at the RCA Dome on January 9, 2005 in Indianapolis, Indiana. The Colts defeated the Broncos 49-24. (Photo by Al Bello/Getty Images)

Is it a good move, or are the Broncos making a multi-million dollar mistake on a guy with a neck that may be as strong as a stale pretzel?

Based on the medical reports available, the pickup is a solid one. And so is the neck.

There are two sets of things you need to know about Peyton Manning:

No. 1: What is wrong with his neck?

No. 2: Why does anyone think it now works well enough to withstand the rigors of the NFL?

First off, Manning has had a total of three confirmed surgeries (and maybe a fourth.) The initial problem was a bulging disk that was pressing on the nerves coming off the spinal cord and running down his throwing arm. Doctors fixed that.

Then — because of some wear and tear of the spinal bones themselves (a.k.a. bone spurs) — doctors needed to clean that up.

Then to stabilize the neck bones, they put in small little plates between two of those bones to strengthen the spinal alignment. (A spine fusion.)

You have seven neck bones that move. Put in plates, and you lose some motion at one of the seven levels.

Recovery from any of the above: four months. Recovery for an NFL’er: four months. If it works.

And then there is Part 2. How do you know this guy can still play the game?

So here’s what we typically do to find out — knowing that Manning had nerves so badly pinched, his arm muscles were only as strong as a Pop Warner quarterback. The muscles literally shrunk and became that weak.

We check X-rays and CAT scans to makes sure the bones look good and the fusion is strong. We take pictures as the neck is flexed and extended to make sure nothing shifts.

We look at MRIs to make sure the spinal cord and nerves coming off of the cord aren’t being pinched.

We do nerve tests on the arm called EMGs and Nerve Conduction Studies — we literally stick needles in the arm and send an electric charge into the muscles to measure how the arm muscles react, and see if the nerves have healed. (Yes it’s a weird test and it can hurt.)

Now let’s say all of that stuff comes back just peachy. The proof now is watching the arm work — hence the Broncos executives’ trip to Duke to watch Manning work out. Will his arm get tired after a dozen throws? Will his velocity drop from 90 to 10 mph? Can he swivel his neck after a fusion?

The good news: it works. Manning threw and threw and threw. Hard. Games worth of throws. On the money. With zip and mustard. And showed the mobility to scan the field and detect a defensive end wheeling off the weak side.

Anything the tests and exams showed needed to be confirmed on the field. And they were. The guy is good to go.

RELATED: Manning Chooses Denver

Final question, though? And it’s not how many throws are in the arm … instead, will a monster shot disconnect his head from his shoulders? In the season of 2012, probably not much more than any other 36-year-old.

Now all we can do is hold our collective breaths until sack No. 1 — and hope he gets up like any other quarterback.

He should.

Get Broncos Gear.