Sidney Crosby gets checked into the boardsJason Cohn / Reuters

Sidney Crosby, one of professional hockey’s biggest stars, was benched indefinitely this week after being diagnosed with his third concussion, putting the season, and possibly the career, of the Pittsburgh Penguin captain and former most valuable player at risk.

Hockey is a fast, exciting, and oftentimes violent sport, as players risk being checked head-first into boards, or fall hard onto ice, or even get punched in the head. Big hits in hockey are as adrenaline-pumping, and sometimes disturbing, as they are in football.

The National Hockey League will now implement new protocols to protect players who sustain concussions on the ice, the league announced Tuesday, a day before the regular season begins.

The league will employ a staff of certified athletic trainers to act as spotters for potential concussions. Spotters will both be at games and at NHL headquarters in New York watching live broadcasts remotely. If spotters see signs of concussions, they can tell teams to remove players from the game. Players can return only after the team’s medical staff clears them. If teams do not cooperate, the league will impose sanctions and fines.

Previously, it was entirely up to the teams and their physicians to determine whether a player is fit to return to the ice. If a player is showing signs of a concussion, he is taken off the ice and examined in the locker room.

This protocol, though, may have have created a conflict of interest, where teams could choose to ignore concussion signs to keep a player in the game. Players could also lie to remain in the game, as former Columbus Blue Jackets defenseman James Wisniewski recounted to The Columbus Dispatch:

I said my back hurt so I didn’t have to do the 20-minute protocol and go through that whole concussion process… A lot of guys were playing through things… That’s playoff hockey. It’s survival of the fittest.

As has been the case in the NFL, repeated hits to the head in hockey can cause brain injuries, like chronic traumatic encephalopathy (CTE), a degenerative disease that leads to suicidal thoughts and erratic behavior. But unlike the NFL, which has been heavily criticized for its handling of concussions on the field, the NHL won’t acknowledge the risk of CTE.

Earlier this year, Senator Richard Blumenthal, a Connecticut Democrat, asked the NHL what its position was on the link between concussions and CTE. In response, NHL Commissioner Gary Bettman wrote in July:

The science regarding C.T.E., including on the asserted “link” to concussions that you reference, remains nascent, particularly with respect to what causes C.T.E. and whether it can be diagnosed by specific clinical symptoms… The relationship between concussions and the asserted clinical symptoms of C.T.E. remains unknown.

Four members of the House Energy and Commerce Committee sent a letter to Bettman on Monday, asking follow-up questions, citing several scientific studies that refute Bettman’s claims.

More than 100 former athletes are suing the NHL, claiming the league was negligent with informing them of the dangers of concussions and brain injuries like CTE. One of those players, Dennis Vaske, retired from the league when he was just 31 after several concussions. He recently told ESPN about one of those times:

On Nov. 22, 1995, while retrieving a puck in his own end, Vaske was driven into the end boards by Eric Lacroix of the Los Angeles Kings. Vaske's helmet came up, exposing his head as he crashed into the dasher boards.

Blood stained the ice in a great pool and leaked into his skull...

“I was out," he said.

Vaske now suffers from severe headaches and emotionally difficult moments, common side-effects of neurological damage. At least six former professional hockey players were diagnosed with CTE after their deaths.

Those are fewer documented cases than in the profession football, which has seen more than 100 former players diagnosed. Indeed, athletes are more likely to get concussions in football than in hockey.

Even so, hockey players face a constant threat of head injuries, from big hits and falling on the ice to fighting and running into the boards. A 2011 study from the Canadian Medical Association Journal found that between 1997 and 2004, players sustained 559 concussions during the regular season, averaging 5.8 concussions per 100 players.

The league has in recent years made efforts to reduce potentially harmful hits during games, including banning blindside hits that target a player’s head and hits that throw player’s head-first into the boards. Bettman even said in 2011, “We celebrate the big hit, we don't like the big head hit.”

Hockey culture has changed in recent years, with fewer and fewer so-called “enforcers” playing in the league. What they lacked in finesse, enforcers made up for in toughness on the ice to deliver big hits and often fight opposing players. As a result of this trend, the number of fights have gone down drastically in the last decade or so. In the 2001-02 season, there were 803 fights, occurring in 42 percent of games, according to hockeyfights.com. Last season, there were 344, occurring in 23 percent of the games.

But the effects of concussions in hockey remain a problem—a fact the Pittsburgh Penguins are more than aware, as the face of the organization, Crosby, will be missing the team’s season opener against the Washington Capitals on Thursday.

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