Im in the same boat, I just recovered from a knee reconstruction from a basketball injury (Replaced ACL, MCL, Trimed Cartlidge, all in all im a new bionic man with a $10,000 Knee

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Have you done your rehab yet? If you haven't started start VERY small. especially on the knee that was scoped. It takes over an entire year to year and a half to finally have your knee completely healed over.
When I started rehab i was on small stretches, atrophy excersices, small muscle contractions, and of course the bike. try not to do any real weights for the first week and a half of your rehab or until you have regained some flexibility from the knee.
Next are small weights. Mostly bagged weights or a sock with coins in it around your atrophied leg and other leg, lay down and life your leg straight up trying to keep it straight and do some reps with that.
After you've become adept at that move to very light machines. Stay away from squats and deadlifts. If you feel that your other leg is smaller here is where you do one at a time. You can even them out with ease, most of the time they even out as you workout. Also make sure you do other machines like butterfly, curls, butts, and calves.
Start out small, don't over due it, it takes a long time. Its been two years for me and i still feel the effect on my knee and tightness. Best of luck to ya
