Foley suffered the injury in Thursday's preseason finale against the Atlanta Falcons while diving to break up a pass in the first half.
Trainer Paul Sparling said on Friday that he expects Foley to recover in time for next season after undergoing reconstructive surgery.
It was ironic that Foley was injured for the final exhibition contest after he sat out the first three games with hip and groin injuries. Foley only played Thursday, so he could take a few snaps before the regular season opener on Sept. 8 against Cleveland.
A 1998 third-round pick, Foley has started 45 of 54 games in his career, collecting 9 1/2 sacks and 158 tackles.