Anaesthetic? Isn't that, like, drugs? Weren't you complaining about, like, drugs on Monday? Do you feel morally OK?
I presume it was an arthroscopic procedure given the hozzy stay? Ron Hill had that done several years ago and didn't allow it to interrupt his long streak of never missing a day running. He ran in the early morning of the (minor) op and then ran late the next day to give maximum hours recovery! The knee'll hurt though as they'd have used a tourniquet and that'll make it sore, I would imagine.