Arthur was hurt December 18 and underwent an MRI exam that revealed the severity of the injury. He is scheduled to undergo surgery within a week and is expected to be ready for the 2012-13 campaign.
The 23-year-old Kansas product averaged a career-high 9.1 points and 4.3 rebounds in 80 games last season. He started 64 games as a rookie in 2008-09, but has come off the bench for all but 10 games over the past two seasons.
Arthur owns career averages of 6.9 points and 4.2 rebounds in 188 career games, all with the Grizzlies.