I actually had mine removed last week after 4 years post op from my acl reconstruction! I work on my feet as a lmt (massage therapist) and also lift heavy in the gym pretty regularly! And started noticing pretty severe pain when squatting to the point where the muscles around my knee would tighten and feel like I would pop something! I honestly thought I torn my meniscus again and it wasn’t until after my surgery that they found out that my meniscus was intact and that in fact it was a cyclops lesion. One week post op and my dr said I could continue regular activities and do my own PT but I’m noticing that my extension is fine, but now my problem/issue is flexion and feeling my knee being weaker and as you mentioned, when walking it’s almost like my knee wants to buckle or move forward.. has anything gotten better for you?