Former National Hockey League star Rick Martin had a degenerative brain disease associated with blows to the head when he died this year, suggesting a stronger link between hockey and a disease mainly associated with head injuries in boxing and football.
A seven-time All-Star and member of the Buffalo Sabres' celebrated "French Connection" line in the 1970s, Martin was suffering from chronic traumatic encephalopathy (CTE) when he died in March at 59 of a heart attack, researchers found.
He is the third former NHL player to have the condition and the first "non-enforcer" to suffer from it.
Enforcers in hockey are the players who most often get involved in fights. But Martin rarely fought, and was known to have suffered only one concussion, suggesting numerous smaller hits over his long career were to blame.
"For me it means that everyone's at risk for CTE," said Chris Nowinski, a researcher at the Boston University Center for the Study of Traumatic Encephalopathy, where Martin's brain was studied after his death. "Now we have the evidence that regular hockey activity can cause CTE."
CTE is associated with depression, memory loss and dementia. It was once known as "dementia pugilistica" since it was long thought to affect only retired boxers.
The first two former NHL players diagnosed, Bob Probert and Reggie Fleming, were known to frequently engage in fistfights with opponents.
"This is more information that we need to process and evaluate," an NHL spokeswoman said in an email about the findings on Martin. "Obviously player safety -- both short and long term -- is the NHL's number one priority."
More recently CTE has been shown to affect former National Football League players. Fourteen of 15 ex-NFL players studied posthumously by the BU clinic have been positive for CTE.
That includes former Chicago Bears safety Dave Duerson, a four-time Pro Bowler. Duerson, 50, committed suicide in February by shooting himself in the chest, reportedly so his brain could be used for research in the BU program.
The announcement on Martin comes as the NHL is preparing to open its regular season Thursday without superstar Sidney Crosby of the Pittsburgh Penguins.
Crosby is recovering from two major blows to the head in January that left him so foggy it was difficult to drive or watch television. He has begun skating again, though has not yet been cleared for full-contact practices.
The NHL has vowed to crack down on hits to the head in an effort to prevent concussions. This year it made it illegal to target the head on a check, and handed out nine suspensions during the preseason for violations.
Still, it's unclear if the disciplinary action will be enough. Last June's Stanley Cup Final was marred by a blindside hit by the Vancouver Canucks' Aaron Rome on Boston Bruins' forward Nathan Horton, leaving Horton with a severe concussion.
Rome was suspended for four games, but Horton didn't return to the ice until late September.
Martin played much of his career without a helmet and never showed symptoms of CTE. He was in stage 2 of the disease, but symptoms are often not apparent until stage 3 or higher on a four-step scale, Nowinski said.
Researchers at BU are currently studying the brain of Derek Boogaard, a former New York Rangers' enforcer who died in March at age 28 from an accidental overdose of alcohol and oxycodone, five months after sustaining a season-ending concussion.
The effects of head trauma in sports often aren't apparent until later in life, however. A study published in June by researchers at Loyola University in Chicago found that more than a third of former NFL players studied showed signs of mild cognitive impairment, a precursor of dementia and a disorder that is likely related to CTE.
The BU researchers say that there is still much they don't understand about the disease.
"We now must learn why some people get the disease and others don't and why CTE progresses more quickly and severely in some individuals than in others," said Robert Stern, a co-director of the research team.
(Reporting by Jason McLure; Editing by Ros Krasny and Jerry Norton)
(This story corrects the start of the NHL season to Thursday in paragraph 11; corrects the spelling of Derek Boogaard in paragraph 17)