Canadian pop-punkers Sum 41 [ tickets ] have canceled the remaining tour dates scheduled in their home country because frontman Deryck Whibley is suffering from a back injury.

The "Strength in Numbers Tour," which paired Sum 41 with fellow Canadian rockers Finger Eleven, has been rolling through Canada since Oct. 11. Dates through Nov. 8 have been canceled in Ontario, Quebec, Newfoundland, Nova Scotia and New Brunswick. Sum 41 was also scheduled to play a radio festival this Sunday (10/28) in Houston.

The band's website continues to list November and December gigs in the US and UK. There are a few Florida radio shows on the books and one in Norfolk, VA; details for those are included below.

Whibley is suffering from a herniated disc and has been ordered by doctors to avoid performing for the next six weeks, according to CanWest News Service. He is said to be recovering at the Los Angeles home he shares with wife Avril Lavigne.

Sum 41 has been out supporting its fifth studio album, "Underclass Hero," which reached No. 7 on The Billboard 200 when it dropped in July. The record marks the band's transition from a quartet to a trio, following guitarist Dave Baksh's exit to concentrate on another act, Brown Brigade. It also marks a new level of maturity for the band.

Whibley, who produced the album himself, opens up on the new material, singing about deeply personal issues including the father he never met and his love life.

"It was hard to even think about a lot of the things," Whibley told LiveDaily in a recent interview. "It was the scariest record I've ever made, by far. It's the scariest thing I've ever done in music."

"Underclass Hero" follows 2004's "Chuck," and last year's live set, "Go Chuck Yourself."