If Green Bay Packers safety Nick Collins intends to persuade Ted Thompson and Mike McCarthy to clear him to play a sport that left him prone and motionless on the field, he's going to need a compelling argument.
His best bet would be to urge the team's general manager and coach to put their faith in medical science.
It is exactly what Collins would be doing if he returned to playing the National Football League's riskiest position for neck injuries.
Roughly six months after New York-based spinal surgeon Frank Cammisa opened a hole in the front of Collins' neck and repaired a herniated disc by fusing two of his vertebrae together, the Packers safety is nearing decision time regarding his career.
And to be sure, Collins wants to play.
He has reiterated to his agents re cently what he told the Journal Sentinel in December, "If everything's good, then we're going. If (doctors) say there's a slight chance of something, then that's it."
Modern medicine has made it possible for a player like Collins, who on Sept. 18 was carted off the field at Bank of America Stadium in Charlotte, N.C., in front of Thompson, McCarthy and his fretting teammates, to play professional football again.
"A lot of people think neck surgery, you'll never be able to play again," said Wellington Hsu, an assistant professor of spine surgery at Northwestern University who did a 20-year study of NFL players who suffered the same injury Collins did. "That was the thought among many spine surgeons.
"In fact, no, you can get back to playing, and you can play at a high level."
McCarthy and Thompson are reticent to allow Collins to play for the Packers again. In their discussions, the two longtime football men have agreed they wouldn't want their own sons to return to full-contact football after a serious neck injury and feel similarly about their star safety.
As badly as they need the three-time Pro Bowl selection back in their lineup, they have stopped just short of telling him he should retire. Sometime before the end of the month they will meet with Collins and his agents and make a decision whether to clear him.
McCarthy has said there must be a consensus among those in the room for that to happen. If the Packers decide they don't want to accept the risk, Collins could ask for his release and play for another team.
Hsu is not alone in his thinking.
Many prominent spine surgeons - including two others with experience operating on NFL players interviewed for this story - are convinced that suffering a herniated disc in the neck no longer draws a go-directly-to-retirement card.
There are ifs and buts that keep each case from being a sure thing, but in general if a player has not suffered permanent spinal cord damage, fully regains his strength and reflexes and isn't suffering from stenosis - a condition where the canal that surrounds the spinal cord is abnormally narrow because of genetics or trauma - it's possible to return to the NFL, the experts say.
"Once everything is healed, the risks are minimal" said Joseph Maroon, the Pittsburgh Steelers' team neurosurgeon and clinical professor at the University of Pittsburgh. "But there's always that risk. Some choose to retire, some continue to play."
Collins underwent a series of tests in New York two weeks ago, the outcome of which haven't been made public and might still be undergoing evaluation.
If they show nothing out of the ordinary, Collins, 28, is going to press McCarthy and Thompson to allow him to resume his decorated and lucrative career.
As ominous as Collins being carted off the field seemed, advancements in medical science have made it possible for him to play again.
The most prominent player to attempt a comeback from a single-level fusion is quarterback Peyton Manning, who sat out all of last season because of a lack of strength in his arms and shoulders and then signed with the Denver Broncos shortly after his release from the Indianapolis Colts.
Each of the doctors interviewed said defensive backs have the highest occurrence of herniated discs, probably because of the innumerable collisions they endure, many against players much larger than them.
Unlike Manning, whose herniation appeared between the fifth and sixth of the seven cervical vertebrae, most NFL players suffer it at C-3 and C-4. The difference is that nerve roots leading to the arms and shoulders are affected at C-5 and C-6, and the spinal cord is affected higher up at C-3 and C-4.
Despite the debilitating nature of the injury, there are success stories.
Take former NFL safety Keion Carpenter, who played seven seasons with Buffalo and Atlanta, three of them after he suffered a herniated disc at C-3 and C-4.
Carpenter collided with Philadelphia Eagles running back Duce Staley in a 2003 playoff game and suffered temporary paralysis, something Collins did not. Two doctors told Carpenter to retire, but he was able to find one willing to clear him after a single-level fusion and went on to play again.
"I think the other two guys just didn't want the liability," Carpenter said of the doctors who refused to clear him. "They didn't want something to happen and be sued. After the fusion, I passed the physical and went back to work.
"I was a little gun-shy at first. You're a little nervous. But one of the most important things was that I had my full range of motion in my neck. I didn't have any serious issues with it. I retired because of my knee, not my neck."
In between every vertebra in the spine there is soft tissue called a disc. It is what allows the vertebrae to bend and slide with the movements of the body, providing a cushion for the bony structure that makes up the spine.
When there is trauma to the spine, as there was when Panthers running back Jonathan Stewart landed on top of Collins' head, bending his neck in an awkward position, the soft tissue can bulge out and make contact with the spinal cord. In Collins' case, the collision was so violent the bulging disc hit his spinal cord hard enough to trigger numbness through his entire body.
"A cord problem gives you those symptoms, the temporary paralysis or numbness and tingling," Hsu said. "You would not expect to have any localized weakness in the arms or hands or anything like that from that injury."
In fusion surgery, the soft disc tissue is removed from between the vertebrae - in Collins' case between C-3 and C-4 - and a bone graft taken either from the patient's hip or a bone bank is inserted between the vertebrae. A titanium plate is screwed into the vertebrae to make sure they don't move while the bone graft fuses to them.
"Then it takes four to eight weeks to heal," Maroon said. "I've had patients return as soon as nine weeks or as long as a year."
One certainty is that if the fusion occurs properly, there won't be a problem with those two vertebrae again. Of all the cervical fusions that have been done on NFL players, not a single one has failed.
"Once that one is fused, then it's game over," said Andrew Dossett, a spine consultant for the Dallas Cowboys and a former football player at the University of Southern California. "It's behind a block of bone. Nothing is going to happen to it."
All three doctors said the player should regain full range of motion in his neck with a single-level fusion.
Though the incidence of paralysis after single-level fusions is zero, it doesn't mean there can't be problems.
If there is an issue after fusion surgery, it isn't with the fused discs but usually the ones above or below them. Because those discs assume the stress from the fused part of the neck, they sometimes will rupture. The player will be forced to retire knowing he might face a lifetime of limited range of motion and discomfort.
"It's a relatively low incidence," Maroon said.
But it does happen.
Baltimore Ravens cornerback Samari Rolle had fusion surgery in 2008, came back the following year and suffered another neck injury that forced him to retire.
"When you hurt your neck, reality sets in," Rolle told the Baltimore Sun in 2009. "My whole attitude changed. If I knew then what I know now, I would have never went back out there."
San Francisco 49ers center Chris Dalman had a single-level fusion of C-3 and C-4 when he was a sophomore at Stanford University. He finished college with no consequences of the surgery and played seven exceptional seasons in the NFL.
During his eighth year, he got hit when he wasn't expecting it during training camp and went down in a heap.
"It kind of exploded through my body," Dalman said. "When I first went down, I couldn't move. I eventually got up and got in the cart and had X-rays and I had another disc herniated between C-5 and C-6.
"It had come back into the (spinal) cord. Every doctor told me I couldn't play anymore."
Like Collins, Dalman wanted to continue playing. His grandfather, father and brothers had played football and he had just signed a huge contract with the 49ers. More than anything he wanted to compete.
His wife was having none of it.
"She said, 'This is it,' " Dalman said. "There is no other option. When I stepped back and thought about it, I said she's really right. When I was single and 19 it wasn't that big of a deal to have the surgery, but I was 30 with two kids."
The second herniation caused Dalman tremendous pain until he finally had a fusion done to C-5 and C-6. He can do all the things he wants to do as a dad - he's also an offensive line coach at a high school in Salinas, Calif. - but he struggles to move his head up and down and reaching to get something out of a tall cabinet is out of the question.
"I really struggle with anything overhead," he said.
Asked if he would do anything different knowing he would have the second herniation, Dalman said, "I'd go back and do it again. It's a great game. It's high-risk, high-reward."
What remains unknown about Collins' situation is whether there are any extenuating circumstances that would cause him or the Packers to pause. Someone who has played the game as long as Collins could have arthritis in other joints in the spine and the surgeon might not be satisfied with the amount of space there is for the spinal cord to rest.
Collins, who has a wife and four children, has told those around him he feels completely normal and has for some time. He apparently has regained all the strength and reflexes he had before the injury and is bouncing off the walls in anticipation of returning to the game.
But Cammisa, who on Sept. 30 operated on Collins in New York City, must concur with team physician Patrick McKenzie that there are no extenuating circumstances that could put Collins in danger. Were Collins to suffer damage to the cord in the same spot where it was contacted that day in Charlotte, he could face serious consequences.
"I've told him, why come back?" his agent, Alan Herman, said recently. "You've got more money than you can spend. But I don't think it's any different with Nick Collins than it is with Peyton Manning. That's why Peyton Manning has come back from a neck injury. They like to compete. They're willing to accept the risk."
Tom Silverstein wrote: