Two concussions do not always add up to secondary impact syndrome


The NFL is back in the concussion debate after Miami Dolphins quarterback Tua Tagovailoa suffered two major concussions in just four days.

This time, the debate is whether Tagovailoa was properly cleared to play because some fans were at risk of a condition called second impact syndrome.

On Sunday, Tagovailoa left a game in the second quarter after a hit by Buffalo Bills’ Matt Milano caused him to fall backwards and hit his helmet on the field. Tagovailoa tripped and fell.

NFL Network reporter Ian Rapoport said Tagovailoa was checked for a concussion and cleared, and returned to the field in the third quarter.

In Sunday’s postgame press conference, Tagovailoa explained that he felt as if he had hyperextended his back.

“My back kind of locked up. But for the most part, I’m good. They passed concussion protocol,” he said.

On Thursday, Tagovailoa returned to the lineup against the Cincinnati Bengals. In the second quarter, he was sacked by defensive lineman Josh Tupou and was carted off the field on a stretcher for several minutes before being sent to the hospital for evaluation.

The Dolphins reported that Tagovailoa was diagnosed with a concussion at the hospital, but was cleared to return home with his team. On Friday, head coach Mike McDaniel said Tagovailoa is following the NFL’s concussion protocol, with no clear timeline for when he will return to the field.

A concussion is a brain injury that causes the brain to move back and forth inside the skull after a blow to the head. But even after the organs have stopped quivering, there can still be changes in the brain.

Neuroscientist Julie Stamm, assistant clinical professor in the Department of Kinesiology at the University of Wisconsin-Madison, describes it as a cascade of chemical events. “It takes time. Each of these brain metabolites and chemicals has a different pathway in how they are recovered,” he said.

He noted that it usually takes 10 to 14 days for the brain to return to its original state.

Stamm has not treated or evaluated Tagovailoa, but noted that, based on what he saw in Sunday’s game against the Bills, it is very possible that he suffered a concussion.

“At first he took the helmet and shook his head. That is a clear sign that you are trying to shake off the cobwebs,” he stated.

Watching him fall was especially disturbing. “It didn’t look like it was the back that caused the fall. It looked like he just lost his balance, and then his teammates are trying to hold him.’

He said the team followed convention protocols and allowed Tagovailoa to return to the game.

McDaniel later told reporters, “The bullet came out in the lower back. He ducked the quarterback sneak earlier. … Her legs shook because her back was loose. As he described it, his lower back was like Gumby.

But Stamm acknowledged that even if someone doesn’t notice symptoms, they may have a brain injury. “He probably felt better afterwards, so maybe he didn’t feel any more symptoms.”

Before Thursday’s game, social media made it clear that Tagovailoa had been injured since Sunday. But after Thursday’s hit, many fans began to suggest that Tagovailoa may be suffering from second-impact syndrome.

“Nowadays we think it’s a second impact syndrome, or a second impact before the first one is resolved. And this can cause uncontrolled swelling of the brain,” he explained. Steven Broglio, director of the University of Michigan Concussion Center. He has not participated in the care of Tagovailoa either.

Broglio said to think of your skull as a box, with your brain inside the box. In second impact syndrome, the second impact compresses the chest, and can stop the parts of the brain that control vital functions like breathing and heart rate from working.

Stamm said the changes happen very quickly and can lead to permanent brain damage or even death.

But Broglio and Stamm emphasize that secondary impact syndrome in this sense is very rare, and usually occurs among young athletes.

“This is a part that we do not understand well, but it is usually only in the youngest athletes; so middle school or high school,” Broglio said.

Although Tagovailoa was concussed in Sunday’s game, what happened Thursday night would not be second impact syndrome in the usual sense, Broglio stressed. “If someone had brain swelling and brain herniation at the bottom of the skull, they wouldn’t be out today.”

But also without brain swelling, a possible second concussion could worsen recovery, Stamm added.

“When someone has a second stroke before the first is healed, we often see worse symptoms than the first. Those symptoms can be more severe. Symptoms tend to last longer. Recovery is much slower,” he said.

Of greatest concern to Stamm after Thursday’s blow, Tagovailoa’s hands were stiff and open, a stance known as the fencing response.

“It was something that jumped out at me right away,” he shared. “Anytime you have a posture like that, it suggests a possible brainstem injury.”

McDaniel admitted after the game that “it was a scary moment. … It was an emotional moment that’s not part of the deal that anybody signs, even though you know in football it’s an opportunity to have something that you have to take out on a stretcher.”

On Friday, Tagovailoa released a statement on Twitter that said: “I feel much better and am focused on my recovery so I can get back on the field with my teammates.”

The NFL Players Association is conducting an investigation into whether the Miami Dolphins violated concussion protocols to determine if Tagovailoa is ready to play.