Don't over think it too much. Especially post injury then your best may not be the generic 'perfect'.

But practicing pedaling at higher cadence as exercises (best on a trainer) up to 130rpm for 30-60 second intervals will get you to learn to pedal in a more circular way and avoid pistoning. Same with the one legged drills, but until you're confident you've got good basic technique and no injury impingements I think one legged has as much chance of re-inforcing bad technique as good.

Often the description of pedalling like you are scraping dirt off the bottom of your shoe at the bottom of the stroke is used, and that 'pedal circles not squares' maxim too.


Final thing, fit is incredibly important. You can't use good pedalling form if your saddle height and cleat position isn't really good.

2 fit items that can aggravate the knee, seat too low, seat too far forward