The former Blackpool ace is currently on crutches after limping off during the 3-2 defeat to QPR.
However, talk of an operation is premature at present and there are no plans to perform surgery on Adam.
Manager Kenny Dalglish and his medical staff are to wait 10 days before choosing to send the 26-year-old under the knife, and are hoping he can play before the end of the season.
"We know Charlie has strained knee ligaments, but we still don't know how long he will be out," Dalglish told the club's official website. "He hasn't had an operation and as it stands he's not having one.
"It's only been a week since he did it. He needs to rest it for another 10 days or so and then he will be reassessed.
"We'll see how he is then and we'll be in a better position to know when he will be back playing.
"We haven't ruled him out for the rest of the season. We're just waiting to see how he progresses."
Adam joins a lengthening list of players, including Daniel Agger, Craig Bellamy, Martin Kelly and Glen Johnson, on the the treatment table.
But Dalglish has hinted that some of the players currently out could play some part during the weekend's encounter with Newcastle United.
"They are all making progress," added the Liverpool boss. "They are all training to various degrees and we will monitor them throughout the week.
"If they're ready to play, they will come back into our plans for Sunday."
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