Just an update, those with similar knee issues may find interesting.
So it’s a week after the injury, and the knee still hurts bending past 90 on flexion, on full extension, and under torsional stress, and I still limp a little when I walk.
But I was getting uneasy about going any longer without squatting as I am going on vacation where there’s no gym (Yukon River) and I injured it right on the day before squats, so I’ve gone about 16 days no squats (I do an 8 day cyle, squats and deads on different days exactly 4 days apart, 1 day on / next day off throughout).
Also, I injured the patella tendon in same knee about a year ago and had to take 2 months off from squats - it took quite a while to get the weight back up, although I did take the opportunity to clean up and re-learn my form quite a bit. This was also based on advice from an old-timer that “it’s better to take two months off and come back, rather than injure it completely, have surgery, and to take a year or more off, maybe to never squat again…” - good advice in some cases, but…
Deadlifts went OK about 4 days ago as long as I stayed around 80%of 1RM and repped (405x6), but the knee was tight but not too painful, so I stopped short of what I could have done.
So I warm up tonight for squats, had real low expectations. Start with just the bar, it kinda hurts but I have good range and stability. Add 45’s, still hurts, not as much. Add another set of plates to 225, actually feels much better!
So, I test it @ 315, and modify my stance a bit wider and try to push my feet apart - advice from a recent article here on T-Mag, and to my surprise it doesn’t hurt at all!
Work sets @ 365x5, 385x5, 405x4, then a rep out @ 365, good depth, no pain, good stability.
Rack the weights and try a leg curl, no effing way, hurts bad just trying to start the curl…
Go figure?
Squats I can’t live without!
Leg curls? Oh well! 
So a few lessons learned:
- A bit of a break (a week) every now and then is OK, you needn’t worry about loss of strength (if you were indeed “putting out” before…)
- Injuries, in some instances, may be worked through. Experiment.
- Use the injury or time off as an opportunity to come back and “re-learn” and clean up your form.