It is typically a question that doesn't come with an easy answer, a mystery that goes to the grave with the person lost.

But former NHL enforcer Todd Ewen's family and friends believe medical science can now pinpoint a root cause of his death, one that few saw evidence of during his life. They believe his hockey career did long-standing damage to his brain. And they expect to know, in a few weeks, if they're right.

Last month, Todd Ewen became the seventh former NHL fighter to die in the last five years. The official causes of their deaths have been varied, but the role they filled in life was similar, with punches to the head part of the job description.

What sets Ewen's story apart is how remarkably normal he appeared to be. Nearly 20 years after retiring, he was financially stable, with a successful real-estate business, happy marriage, three sons, a grandson and a wide support network of family and friends.

Ewen had played 11 years in the NHL with four teams, won a Stanley Cup in Montreal and become a respected youth and college hockey coach in the St. Louis area. The signs he was in trouble were minimal. He suffered from depression at times – something he rarely talked about – and struggled with diabetes and the aftereffects of many hockey injuries. Overall, however, he seemed better-off than many retired players.

But on the morning of Sept. 19, Todd Ewen went into the basement of his home, lay down on the floor, and shot himself in the head. Days after laughing and joking with friends about getting out and riding his Harley around in the late-summer sunshine, Ewen was dead at 49 years old.

"Honest to God when I got a call from my nephew that he had heard that I thought 'There's no way in hell,'" said former NHL defenceman Rik Wilson, one of Ewen's closest friends who runs a gym popular with former Blues players in St. Louis. "I texted Todd and just said, 'Hey, you doing okay?' Once his sister confirmed that he had passed on, I still couldn't believe it. It's just out of nowhere."

Ewen's case unfortunately fits a pattern. Ever since Bob Probert – one of the deans of hockey enforcers – died of heart failure in 2010, there has been a growing unease settling in among former NHL players.

In 2011, four more fighters – Derek Boogaard, Barry Potomski, Rick Rypien and Wade Belak – passed away, a string of deaths that drew widespread media attention to fighting in the sport. This season, defenceman Steve Montador – who was not an enforcer but fought nearly 70 times in the NHL alone – and Ewen joined that list.

They were different men, from assorted eras. Several had substance-abuse issues, but others were clean. Rypien was the only other confirmed suicide. But they were all between the ages of 27 and 49, and they all filled the only role in professional team sports that routinely involves punches to the head.

Three of their brains were examined posthumously – Probert, Boogaard and Montador – and all were found to have the degenerative disease chronic traumatic encephalopathy (CTE).

Ewen will potentially be the fourth, as his family donated his brain to renowned Toronto neurosurgeon Charles Tator for his Canadian Sports Concussion Project.

Perhaps because he was so popular, so gregarious and so heavily involved in the community, Ewen's death seems to have hit former NHL players especially hard. Most of the other fighters who died had significant turmoil in their lives for years, overt signs something was seriously wrong. Ewen displayed almost none. The enforcers who knew him, however, say they know what he was going through.

"I was shocked," said Jim Thomson, Ewen's teammate in Anaheim during the Mighty Ducks' inaugural season. "Devastated. But I understood it. Because I was there. Todd was not into drugs. Todd was not an alcoholic. But Todd was depressed. In my days of depression, and chemical imbalance, I had three times where I contemplated taking my life. That's why I came out four years ago and said we need to do something about this."

Thomson's solution back in 2011 was to ban fighting from the game, and he was quickly blasted by Hockey Night In Canada's Don Cherry as a "puke" and "turncoat" for suggesting it. (Cherry later apologized.)

Four years later, Thomson still believes in his message. His voice rises into a shout when he delivers it, a passionate speech about "knuckles to the brain" scaring kids away from minor hockey and doing long-term damage to former pros' lives. He recalls long conversations with Ewen when they were together in Anaheim about how much they loathed their role and the toll it took on them.

In private, Ewen supported Thomson when he spoke out and much of the hockey world didn't listen. "He gave me a hug and said, 'Good for you saying take fighting out,'" Thomson said. "He knew the shit that I went through."

"He hated being a tough guy," said former Blues defenceman Jamie Rivers, another of Ewen's close friends. "He came upon the role because of his size – and that was a high level of stress for him. That job. His whole career he hated it."

Rivers explained that one of the worst things that ever happened in Ewen's career was punching out Probert – then the most feared heavyweight in the NHL – in one of his first games in the league.

Ewen was a talented artist and, throughout junior hockey, had spent much of his time working on his art. He went on to write and illustrate children's books while with the Ducks, including the story of Hop, "a frog who dared to be different." But after downing Probert, he became known as "The Animal" in hockey circles. He was typecast as a fighter the rest of his career, despite scoring nearly 30 goals as a junior.

"Ewey was scared to death," Rivers said. "He just kept swinging until Bobby didn't get back up."

Stress has become a growing problem for former fighters the past few years. Along with the string of deaths of their peers, the increasing medical research into CTE and media coverage of its ramifications has created a deep anxiety for retired players – especially those who dropped the gloves regularly.

Some can recite the graphic details of the more horrific cases in football, including the story of Chicago Bears safety Dave Duerson, who shot himself in the chest and left a suicide note that he wanted his brain examined by researchers.

When Ewen died, the first thing many NHL alumni thought of was CTE. The second was a question. Will they be next?

"There's times where I'm going why are my ears ringing so much?" said Thomson, who has calculated that he had 124 fights after turning pro at 19 years old. "Why am I getting these bad headaches? Why do I feel depressed today? As the years go by, I start to wonder. I don't know. Does it wake me up when I see what Todd did? Oh it wakes me up. It makes me think really hard."

Those difficult questions are why some former NHL fighters have begun to have their brains examined while they're still alive. Brantt Myhres, who had nearly 700 penalty minutes in a 154-game career and was eventually banned from the NHL after continual drug violations, recently had multiple scans done through the Edmonton Oilers team doctor. Myhres had been experiencing post-concussion symptoms for years, but waited nearly a decade to have the tests done.

He was terrified what they would show. "When you get out of the game, your head just doesn't feel right at times," Myhres said. "You start to question that."

His family was relieved when there was no damage visible on his MRIs and CT scans, but the unfortunate reality is that imaging technology is not yet able to spot CTE in the living. Players like Myhres are forced to live with that uncertainty. And even if CTE-diagnosis tests improve, it's not a given players would want to know.

"My family members would say yes," Myhres said. "But that's a tough one. The last thing you want to do is spiral yourself into a depression. That would be really tough."

"That is coming," Dr. Tator said of the CTE-spotting tests, which he explained will likely use advanced MRI or PET technology.

Ewen's death has already begun to change the conversation among former players. Many members of the Blues close-knit alumni group said they wished he had talked to them about what he was dealing with as they would have done anything to help someone they admired so much.

Now they are pressing their friends who played the game to open up, something that doesn't come naturally to a generation of players who grew up being told to ignore their injuries and play through pain. Players also said they view their former teammates differently, seeing them as fragile, middle-aged men worn down by a brutal game.

Many played on the fringes of the league back before salaries exploded. They never got rich or found a calling after hockey. Some live in the past – with tales from their glory days always at the ready – or in their heads, fighting demons real or imagined. If it all caught up with Ewen, they reason, it could happen to anyone.

"When I looked around at the alumni guys [at Ewen's funeral], a couple of them I know have had struggles that were tough guys," Wilson said. "You just hope that if that's the case that there's something treatment-wise or medication that can make things better balanced. We're losing too many good people, that's for damn sure."

"We were programmed to not show pain from a young age," Rivers added. "Your dad would tell you 'unless you're dead, don't lay on the ice.' … Now, after this, guys are starting to reach out more. And I hope this generation of players speaks out more."

Dr. Tator is examining Ewen's brain in Toronto now, and the results are expected to be released in mid-November. He is the 19th subject in an ambitious project that is aiming to study 50 brains of former NHL and CFL players who suffered concussions in their careers for signs of damage. So far, Dr. Tator says, half of the brains in his sample had CTE.

Ewen's former teammates and friends expect the results to confirm he did as well, as that is the only explanation that makes sense to them. The Blues Alumni Association has been collecting donations in Ewen's memory that will be directed toward CTE research.

They hope his death resonates, both with other players and the wider hockey community. They hope their friend doesn't become just another name on a growing, unsettling list. They hope his brain has some answers to questions they never thought to ask while he was alive.

"He was such a giving guy," Rivers said. "Todd would have said yes [to the donation]. If this could have helped one person, do it."

"I just can't say enough," Wilson said, "about how much we're going to miss him."

Derek Boogaard: At 6-foot-8 and 260 pounds, "The Boogey Man" was one of the largest and most feared fighters in NHL history. A Regina native and the son of an RCMP officer, he began fighting at 16 years old, first in Saskatchewan's junior league, and later the WHL, where he scored three goals and had 670 penalty minutes in 174 games. After five years with the Minnesota Wild in the NHL, Boogaard signed a four-year, $6.4-million deal with the New York Rangers – likely the largest contract ever given to a fighter. But Boogaard suffered from severe postconcussion syndrome and other debilitating injuries and was addicted to OxyContin and Ambien. In 2011, he died of a drug overdose at 28 years old. His brain was found to have extensive damage in the form of the degenerative brain disease chronic traumatic encephalopathy. Boogaard's tragic life story was recently chronicled by New York Times sportswriter John Branch in his book Boy on Ice.

Barry Potomski: Undrafted into the NHL, Potomski nonetheless fought his way up in the mid-1990s with the Los Angeles Kings and San Jose Sharks after years in the lower minor leagues. He fought in five different pro leagues with 10 different teams over nine seasons, ending his career in 2001 with 227 penalty minutes in only 68 NHL games played. In 2011, he died of an apparent heart attack at a fitness centre in his hometown of Windsor. He was 38.

Rick Rypien: At only 5-foot-11 and 170 pounds, Rypien was an unlikely candidate to make the NHL as a fighter. But his father, Wes, was a Canadian boxing champion, and he proved to have similar talents, quickly becoming dominant at the AHL and NHL level through a combination of smarts and speed. Rypien became a fan favourite with the Vancouver Canucks but had just signed with the reborn Winnipeg Jets when he took his own life in the summer of 2011. He was 27.

Wade Belak: With a big grin and big heart, the 6-foot-5 Belak was enormously popular with players, coaches, media and fans throughout his 14-year NHL career. A high draft pick, he had to adapt to stay in the league, moving from defence to wing and becoming an enforcer despite the role being in direct contrast to his larger-than-life personality. Belak played in Colorado, Calgary, Florida and Nashville but is best remembered as the endearing protector for the Toronto Maple Leafs between 2001-08. While filming the Battle of the Blades figure-skating series with CBC in 2011, he was found dead in his Toronto hotel room at 35 years old. Friends and relatives said he had quietly suffered from depression for years.

Steve Montador: The definition of a gritty journeyman, Montador was never drafted but went on to play nearly 600 games as a two-way defenceman in the NHL with Calgary, Florida, Anaheim, Boston, Buffalo and Chicago. Montador's career ended tragically, as he suffered from debilitating postconcussion issues and related depression in the later years of his life. He died at age 35 this past February from an undisclosed cause. Heartbreakingly, his son was born four days later. Researchers who later autopsied Montador's brain found he had CTE.

Bob Probert: A legendary figure among hockey fight fans. Probert grew up in Windsor, Ont., and went on to become the rare enforcer who was a star, playing for the Detroit Red Wings just across the river. He skated in nearly 1,000 NHL games and finished fifth in career penalty minutes with an incredible 3,300. His best season was in 1987-88, when he scored 29 goals and led the league with nearly 400 penalty minutes. Probert had serious drug and alcohol issues throughout his career and, in 2010, died of heart failure at the age of 45. Researchers who examined his brain found he had CTE.

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