It's not only a matter of healing from the injury, but also recovering strength and conditioning that will be affected by this. I am a huge Lang booster, but I doubt that he will be able to come back and play effectively unless it is in May or later.
If Lang is able to comeback during the play-offs it would be a huge help! If they make it to the second round, having a Fresh Lang come in would help them a lot and I sure hope he does.. He seems like a great team guy and he's also a big body..