Unexpected Feelings (1.5 yrs Post-Op)

Generally I try to think positively about my knee. I've long since gotten back to most of my favorite activities (and most recently- indoor volleyball!) and being out and active gives me the impression that I'm 'all better' even if I openly admit that my surgical leg still has a smaller quad and some actions, such as jumping in place on one leg, feel decidedly different from one leg to the other.

In the last few weeks my surgical knee has been feeling... different. It seems to be a combination of feelings, not necessarily at once, that's had me mentioning to family and friends that it feels "funny". For example:

• In day-to-day motions my knee will suddenly feel tight like it's about to pop or crack to relieve the tight feeling. Sometimes it does pop or crack, other times I stop quickly enough where it feels like it got on the cusp of popping, but I change my motion to avoid it. The times that it does pop or crack is not painful, but slightly annoying.
• When sitting on a chair, with my legs straight out in front of me, I will apply a little pressure just below my patella (to the area where my graft was taken from). Keeping this pressure, I first flex my legs (straighten) and then start to bend them slightly (both legs at the same time). My surgical patella will sometimes feel like it's 'catching' or even 'grinding' as it slides up during the bend. I realize this is a very specific motion / feeling, but the engineer in me wants to put the knee in certain situations to see how it reacts compared to the non-surgical side!
• No matter how much I try to stretch, loosen, warm-up or manipulate my surgical knee, it seems to have a feeling like the pieces of the joint are not allowed to move as freely as the non-surgical knee. Imagine a non-surgical knee being surrounded by water whereas the surgical knee feels like it's moving through something thicker- like jello or pudding. Not painful, or even limiting, just... different.
• It's since gone away, but at one point when I would straighten and flex my surgical leg there seemed to be a popping noise at the BACK of my knee, towards the inside. I seem to recall this happening during rehab, and we attributed it to the swelling in the knee pushing parts of the joint out of place and hitting nearby veins/tendons/what-have-yous. So, either that was just a guess at the time, or perhaps there was some additional swelling in my knee recently to bring me back to that feeling. Either way, that particular popping/uncomfortable feeling has since passed.

I think with the change in weather and also sports seasons, now would be a good time for me to reconsider a continuous 'rehab' plan for my knee. I've got a BOSU ball that's gathering dust, and don't spend nearly enough time stretching before my various sports. I think it would be wise for me to get out for a run and some PT-like exercises more often before Michigan's winter weather sets in and I'm forced to strictly indoor activities.

On a lighter note, whenever I'm in the middle of an activity, the knee doesn't pop (that I notice!) or have any continuous feelings of pain or soreness that limit me. Perhaps it's that I'm distracted with the sports, or that in the faster movements the knee is performing like it's been (re-)designed to!