Anichebe ruled out for rest of season
The Nigerian damaged the cartilage in his right knee in the game against Newcastle United on February 22 after being fouled by Kevin Nolan, who was sent off for his challenge.
Anichebe had a scan on the knee and saw a specialist in London on Wednesday but the results were inconclusive and he will now undergo exploratory surgery.
"It's a blow for the boy as he'd just got back into the team, and it's another player we have lost," manager David Moyes told the club's website.
Everton have already lost striker Yakubu Aiyegbeni for the season while Michael Vaughan is likely to come back into contention only for the last few weeks.
Louis Saha has only just returned to action and Everton have played for the last two months with Australia midfielder Tim Cahill as an emergency forward.
Midfielder Mikel Arteta is also out for the season with a ruptured knee ligament.