Bell had surgery Wednesday to remove loose body from his left knee. He should return to baseball activities in 2-to-4 weeks.
These types of routine cleanups typically take place earlier in the offseason, so the loose body was likely just recently discovered. It sounds like he may not be ready for the team's first spring training game, but he should have enough time to get ready for the regular season. Bell can use all the reps he can get defensively at first base and at the plate against left-handed pitching, so this is untimely, but his fantasy value should not take much of a hit as a result.