"Andrew Surman will definitely be out and that's a blow for us. It's hard to say right now, but that could be his season," Howe told reporters on Tuesday.
Bournemouth, who are 11th in the table on 34 points and unbeaten in their last four games, travel to Anfield to take on third-placed Liverpool on Wednesday.
Bournemouth beat Liverpool for the first time earlier this season, emerging as 4-3 victors after a thrilling encounter at the Vitality Stadium in December, but their last two visits to Anfield have ended in narrow 1-0 defeats.
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"Liverpool will be a really tough test for us," Howe added.
"We respect them and their manager. We've done okay at Anfield in recent games. The home game against Liverpool was arguably our standout game of the season so far, but it's of no relevance now. This is a new game."
The Liverpool match marks the start of a tough run of fixtures for Bournemouth, who host leaders Chelsea on Saturday before travelling to second-placed Tottenham Hotspur a week later, but Howe said his team was up to the challenge.
"We want to gather as many points as we can. The challenges in our next three games are tough, but ones we have to relish.
We're in a good place at the moment. We're also aware of how quickly things can change in football."
(Reporting by Aditi Prakash in Bengaluru; editing by Mark Heinrich)
