Toeing the fourth line

But one of the sharpest indicators of the Bruins’ success last year was the playing time of Shawn Thornton.

Over 79 regular-season games, the fourth-line wing averaged 10:02 of ice time. That Thornton skated more than 10 minutes per game illustrates that the 2008-09 Bruins rolled four lines consistently, taking pressure off top players. That they weren’t taking penalties (12.5 minutes per game, fifth-fewest in the NHL). That they were committed to sending out Thornton and his lunchpail linemates to wear down opponents with their thump-first play.

“When the top guys go from playing 24 minutes to 22 minutes, it’s a big difference,’’ Thornton said. “If we can eat up those extra couple minutes and give them some extra rest, they can be that much more fresh. It’s not rocket science.’’

Coaches around the league vary in their fourth-line approaches.

The Rangers’ John Tortorella prefers to lean on his top three lines and sprinkle in his fourth-line lads sparingly. Detroit’s Mike Babcock likes to roll four lines to keep his forwards fresh and on the attack. Last season, Julien was in the Babcock camp, with a threesome of Thornton, Stephane Yelle, and Byron Bitz being the most effective formation on the No. 4 line.

As the wingers, Thornton and Bitz were responsible along the walls in their own zone, chipping pucks out and sparking the transition game. In the offensive zone, the big-bodied wings played straight-line hockey to hammer defensemen and create scoring chances. Anchoring the wingers was Yelle, the savvy center with off-the-charts hockey sense.

“He was just so smart defensively,’’ Bitz said. “He took care of his own end first. When me and Thorny are in there cycling the puck, he’d be out high, somewhere in a position where he could get back and help out. That was the biggest thing. He’s such a smart player.’’

Two years ago, with less offensive depth on his bench, Julien chose a more top-heavy approach. In 2007-08, Thornton averaged 7:23 per game as the Bruins scratched out an eighth-place finish. In the same season, Marc Savard got 20:31 of ice time per game.

Last year, as Thornton’s ice time increased, Savard saw nearly a full minute shaved off his workload (19:32 per game). More time for the hard hats? More rest for the skilled guys.

The Bruins, however, will have to adjust to the loss of Yelle, who signed with Carolina during the offseason. While there could be surprises during training camp, former Canadien Steve Begin should start the year in Yelle’s spot as fourth-line center. And if that takes place, the fourth line could become even surlier and harder to play against.

Yelle is no floater, but Begin is considered one of the league’s feistier forwards.

“I’d rather play with him than against him, that’s for sure,’’ said Thornton.

In 2007-08, Thornton learned that the hard way. In the first-round Boston-Montreal showdown, it wasn’t the star players like Alex Kovalev, Tomas Plekanec, or Andrei Kostitsyn inflicting the most damage. It was Montreal’s energy line of Begin, Bryan Smolinski, and Tom Kostopoulos that pounded, crunched, and snarled its way through the Boston lineup.

“Definitely the best line,’’ said Thornton, who was centered by Vladimir Sobotka during the series. “We played against them most of the time. We played well, but they outplayed us. They were good. They were fast, gritty, and always all over the puck no matter where it was. They were relentless. [Begin] is a thorn in your side, that’s for sure. No doubt about that. I think everyone in the league knows that.’’

Begin, who arrived in Boston last week with his wife and two children, understands his job description. Like Michael Ryder, Begin played for Julien in Montreal. He promises to finish his checks, block shots, and be responsible defensively, knowing that his former coach trusts his fourth line to do the dirty work that might not translate to dollars, but ultimately produces wins.

“Sometimes we were down and we’d have a good shift, create some energy, and maybe shift the momentum,’’ Bitz said. “So it wasn’t always when we were up that we played a lot. Sometimes when we were down, we’d have a little more ice to try and get momentum. We’re an energy line. We have to get momentum.’’

Surgeon provided hip service to Regan

So on April 20, Regan visited Dr. Bryan T. Kelly to repair a torn labrum and an impingement in his hip. Nearly two months later, Kelly would operate on David Krejci’s hip to repair an impingement.

“Guinea pig,’’ Regan cracked. “Send me down first, make sure everything’s OK, then send the guy with all the money down.’’

Last summer, with help from strength and conditioning coach John Whitesides, Regan focused on core work to build up his hips, groin, and back. But Regan would learn that his injury was a wear-and-tear case, with surgery the endgame.

And the way Regan sees it, an equipment change didn’t help things either. Prior to last season, goaltenders were required to take out a chunk of padding from inside each knee, the rationale being that shooters would have greater five-hole scoring opportunities. The piece of padding, however, cushioned goalies from hitting the ice flush with their knees, a motion that places additional strain on the forced-to-rotate hips.

“Just that extra few inches, that’s more rotation in your hips,’’ Regan said. “Over the course of a season, it adds up.’’

Goaltenders who have suffered torn labrums include Rick DiPietro and John Curry, also former Hockey East stars like Regan. The repetitive motions required of butterfly goalies ensure that more puck-stoppers will fall victim to hip woes.

The hope, however, is that the surgical fix - Kelly and Dr. Marc Phillipon are two who specialize in the procedure - becomes akin to Tommy John surgery, with post-op goalies becoming stronger than they were before.

Etc.

Fluto Shinzawa can be reached at fshinzawa@globe.com.