It's the same knee James had scoped before the bye, but it's not the same injury. James was injured during Sunday's victory over Kansas City, indicating that the injury wasn't the result of a hit.
Kendyl Jacox replaced James at left guard against the Chiefs, so it's only logical that Jacox would get the start against Minnesota.
Because Jacox was removed from the starting lineup earlier this season after one start at right guard, it's not impossible we could see newcomer Toniu Fonoti in the starting lineup once he's ready to play.
Either way, though, it's a disappointing setback for an offensive line that really has played well for the last month.