Glad all is at least nominally well where you are. And yes, I'd wager your stepfather will be surprised, if not outright shocked, by how much better he feels once he has his knees attended to ... I have a relative who is effectively allergic to sutures who has a similarly bad knee, and they know (having a medical background) what they could have otherwise in terms of pain relief. The sooner someone can cajole, convince, or (kindly) coerce your step into taking the jump into getting things fixed, the better he can feel, I suspect. But everyone must make their own decisions, I know. Best to you and yours. Be well!