Blackhawks captain Jonathan Toews is shaken up in a 3-2 loss to the Canucks. ((Nuccio DiNuzzo/Associated Press))

Concussions have come to the forefront once again with the weebles and wobbles of Montreal Canadiens defenceman Marc-Andre Bergeron and Chicago Blackhawks captain Jonathan Toews after they were on the receiving end of ferocious bodychecks this week.

There was little debate that the shoulder hits delivered by Atlanta Thrashers forward Colby Armstrong on Bergeron and Vancouver Canucks defenceman Willie Mitchell on Toews were clean. The real issue was why was Bergeron allowed to continue playing and practiced the following day, while the Hawks, who reported that Toews may be available to play on Saturday, immediately left his game and was kept out of practice on Thursday?

The easy answer is that as frightening as it is to watch a player like Bergeron or Toews become dazed and confused on the ice, each player is a case-by-case situation.

We asked Calgary Flames team physician Dr. Kelly Brett to take us down to the bench and into the dressing room and explain how a player is checked out when he suffers a possible head injury.

Brett, 47, has been with the Flames for nine years and has played competitive hockey and rugby all his life. He works for the one of the toughest general managers in the league in Darryl Sutter, who still has old-school values, but the good doctor adheres to strict protocol developed by the Flames medical staff.

"In Calgary, we sit behind the bench and have a bird's eye view," Brett said. "Every team's policy is different. If a person has a head injury or a suspected concussion, we assess them as a medical team."

The first person to see the player is Flames athletic therapist Morris Boyer. He asks the player in distress a few standard questions to see how the player feels and if he is aware of what happened and his surroundings.

"We obviously watch the game differently than the average fan," Brett said. "If a guy gets hit hard, you watch and you see if he looks dazed. After that, it really depends on the player to tell you how he feels at that point."

But sometimes, the Flames medical staff can skip this on-the-bench interview stage.

"If they are like Toews and they get the Bambi legs and stagger and fall down like he did [on his way to the bench], well, it's pretty obvious that the guy has suffered a concussion. The ones that are more difficult are when you're relying on him to tell you if he's OK.

"Depending on the player, depending on their status on the team and other variables, he may or may not give you a true feeling. But if the guy is cleared, we watch him on the next shift or two. If he goes out there and skates backwards and tries to score on his own net, then you know it's time to get him off the ice."

'Players are more aware now'

One of the positive developments in concussions in the NHL that Brett has noticed in his time with the Flames are players are more willing to report concussion symptoms.

"It's a lot different than, say, 15 years ago," Brett said. "Players are more aware now of the long-term issues associated with concussions and that they not only can be career-threatening, but life-altering. Plus, the guys are making a lot of money and with most injuries players are reluctant to return until they are fully recovered."

Under an older system, trainers and doctors used to grade a concussion. That has been done away with because, like the Bergeron and Toews situations differed, there's a whole bunch of factors to consider. Does a player have a concussion history? How is the player going to feel in a couple of days?

"It's impossible to play collision sports like hockey, football, rugby without having a risk of getting a concussion," Brett said. "We would like to see headshots taken out of the game because that is something associated with concussions, but you can't eliminate concussions in hockey.

"The hit on Toews was a clean hit. He was just in an awkward position with [Mitchell] coming out of the penalty box. That's just part of the game."