"Junior Stanislas could be out for three to four months, it's a big blow for us," Howe told reporters ahead of Saturday's Premier League trip to 16th-placed Southampton.
Adam Smith, who picked up a muscle injury in the warm-up to the Fulham game, will also miss the clash at St Mary's and Howe was hopeful the defender's problem was not too serious.
"We'll have to see if he's back before the end of the season, we're hopeful he's not someone with a long-term injury," Howe said.
Bournemouth were beaten 2-1 at Southampton last year and Howe sought a response from his players.
"We'll need to be at our best," Howe added. "It's so important for us to end the season strongly, we're hugely motivated to get the result."
Bournemouth are 14th in the table with 41 points from 35 games.
(Reporting by Shrivathsa Sridhar in Bengaluru; editing by Sudipto Ganguly)
