Hockey Canada announced Friday that forward Colton Sissons of the Kelowna Rockets in the Western Hockey League will be unable to attend Canada's selection camp next week for the World Junior Championship due to an upper-body injury.

Sissons will not be replaced on the roster, which now has a total of 36 invitees, including four goaltenders, 12 defensemen and 20 forwards. The 19-year-old Sissons was drafted by the Nashville Predators in the second round (No. 50 overall) of the NHL Draft last June. He had 10 goals and 27 points in 27 games for Kelowna in 2012-13.

Expect Canadian National Junior Team head coach Steve Spott to undergo his share of sleepless nights when he begins his evaluation of players at Hockey Canada's selection camp in Calgary next week.

Defenseman Ryan Murphy is one player who won't require much evaluation, however.

Murphy, chosen No. 12 by the Carolina Hurricanes at the 2011 NHL Draft, was one of 37 players (12 defensemen) invited to Hockey Canada's selection camp at the Markin MacPhail Centre at Canada Olympic Park in Calgary, Dec. 11-13.

Spott has coached Murphy the past four seasons with the Kitchener Rangers of the Ontario Hockey League. This year marks the third time Murphy finds himself in a position to represent his country at the World Junior Championship -- he was released prior to the final roster selection the previous two years.

In addition to top draft-eligible defenseman Seth Jones, one other standout prospect was invited to the U.S. National Junior Team selection camp at the New York Rangers' training facility in Greenburgh, N.Y., from Dec. 16-18.

Ryan Hartman, a 5-foot-11, 187-pound forward from West Dundee, Ill., is also on the radar of USA Hockey's coaching and managerial team -- and for good reason.

"I really liked his camp in Lake Placid [in August]," U.S. National Team coach Phil Housley said. "He's the kind of guy who plays at both ends of the rink, can skate, and can change the momentum of a game with a big hit."

Three weeks from Wednesday, the first puck will drop to start the 2013 IIHF World Junior Championship in Ufa, Russia.

NHL.com already has started covering the event, which runs Dec. 26 to Jan. 5 in Ufa, Russia, with the publication of a number of stories, starting with the selection camp rosters for a number of the leading hockey nations, with more to come.

Canada's selection camp will be held Dec. 11-13 at the Canada Olympic Center in Calgary, while the U.S. selection camp will be held Dec. 14-16 in Greenburgh, N.Y., at the New York Rangers' training facility.

Check this blog often as NHL.com will have full coverage leading into the tournament all the way to the gold-medal game.

NHL Network-US is the home of the 2013 IIHF World Junior Championship with coverage of more than 15 games as well as highlights and analysis.