There is no NFL protocol for the rest of the body. Get a concussion and, due to the vagaries of the injury and the league's long failure to treat head shots seriously, a player has to pass a series of tests and be cleared by an independent neurologist.
Injure your hand, break a rib, tear a ligament, sprain an ankle - do any of those and a player is not only free to play if he can, he is celebrated for his toughness. Playing hurt adds to the mystique, especially for quarterbacks.
That's why Michael Vick was talking about his inability to finish the last two games as if they represented some kind of failure on his part. Vick was concussed in Atlanta and his right hand was too swollen Sunday to bend his fingers and grip the football properly. He wanted to return after the concussion, but was not allowed. He did come back after hurting the hand, but was finally forced to the sideline.
His reaction to all that?
"I'm tired of letting my guys down," Vick told reporters Wednesday. "I'm not coming out of the game this week regardless. They're going to have to cart me off."
It is admirable, in its way, this recklessness. Certainly, we in the media do our part to make it seem heroic. When Tony Romo led the Dallas Cowboys to an overtime win shortly after suffering two broken ribs and puncturing a lung, then came back and led his team to a win over Washington on Sunday, he was treated as if he'd ascended to a new level of NFL greatness.
Personal disclosure: I've been guilty, too. When Roy Halladay pitched in San Francisco on a sore knee, I praised him for it. When Philip Rivers played an AFC championship game with a torn knee ligament a couple of years ago, I wrote about him even though San Diego lost to New England. And there were all those injuries Donovan McNabb played through: broken ankle, bad thumb on his throwing hand, sports hernia.
"I heard Tony Romo say the other day, 16 days are required for this job, and those are the days that you want to be out there," Vick said. "To not be out there, it was tough the last two weeks, and I'm going to do everything in my power to make sure I can finish each and every game for the next 13 games."
The call seems a little easier to make with the hand injury than with the concussion. Vick went through the league protocol in the days after banging heads with Todd Herremans in Atlanta. He was cleared to play, and he did. The unanswered, and maybe unanswerable, question is whether he was back to 100 percent or still a little foggy.
"I didn't see that," coach Andy Reid said. "He was as sharp as ever, so I didn't see anything."
But the TV cameras caught Vick reaching for his head after a couple of hard hits. And there was that strange sequence late in the first half when Vick appeared to be trying to get the team lined up for a play, or to spike the ball. Thing is, it was fourth down, and the field-goal unit was already out there.
Vick said he would draw the line if his presence on the field "hurt the team more than I can help it. I'm not that selfish."
Reid said the line had more to do with the player's well-being: "If he can't function and play and not get hurt, we're not going to put him out there," Reid said. "It's that simple."
Take that literally and no one would be out there. Injuries are part of the game, and every player knows the risks. Or thinks he does. And this is where the cult of toughness, of playing hurt, becomes a little dubious.
As I've written before, I chanced to have a long phone conversation with former Eagles safety Andre Waters a few months before his suicide. Waters was later found to have brain damage consistent with a number of concussions, which almost certainly contributed to his depression. But when he talked about his troubles, he focused mostly on the general pain he awoke in every day.
He not only ached in every part of his body, Waters could identify each pain with the particular collision that caused it.
Whether it's Vick or McNabb, Romo or Rivers, players can't imagine that future suffering when they're deciding whether to play in pain. They care about now, about winning, about being there for their teammates.
Their motivation is noble enough. Their actions are hard not to admire. But deep down, you have to wonder whether someone should step in and take that decision away from them.