The 24-year-old went under the surgeon's knife to remove damaged cartilage after complaining of discomfort and swelling last week.
Faulconbridge is top scorer at Adams Park this season with six goals to his name and the news is a bitter blow to the Buckinghamshire outfit.
Manager Lawrie Sanchez said on the injury: "It's disappointing because it was a training-ground accident and it was a real surprise."
The forward will now concentrate on regaining full-fitness for The Chairboys next campaign in Division Two as they appear to be out of the running for a play-off place this time round.
