@doodles418 had asked about my experience with a second manipulation – what was my experience like, was it painful, did it help, and how did I know if it was scar tissue, when did it occur during my recovery?
My recall on the exact details may be a bit fuzzy because I had my knee replacement in 2006 (can't believe it has been that long already). I had end-stage arthritis in my right knee caused by a genetic bleeding disorder that prevents my blood from clotting on its own. When I was a child, the medication to help this disease (hemophilia) was not as good as it is now. Essentially, my blood wouldn't clot without injecting the clotting factor that I was missing. Most people think a cut is the issue, but the bigger issue was internal bleeding. My right knee was my "target joint" meaning I continually had internal bleeding in that joint as a kid which led to arthritis at age 8. By the time I was 19, my knee was completely arthritic and deformed – it was no longer a ball & socket joint, the bones had worn to squares. Because of this my knee – prior to surgery – had not been able to straighten to 0 degrees for almost a decade already. So I went in to surgery fighting all sorts of muscle and ligament atrophy as is.
My initial recovery from the replacement was awful. The ligaments were stretched straight upon waking up for the first time in 13+ years so the pain was intense. Scar tissue took hold almost immediately (likely due to my young age and immune system being much more active than waiting until later in life). Ultimately I had to have a manipulation – more painful to wake up from than the actual surgery. Scar tissue took hold again and I had to have another manipulation, I believe somewhere close to the 8 month mark from the original replacement (but could be closer to one year). Unfortunately, that still did not do the trick. I was told at that point that you cannot do additional manipulations because the scar tissue becomes strong enough to risk breaking your femur at that point.
To answer the question of how did they know, it was determined via x-ray to show the joint itself was not the issue and based on the mechanics they determined it was most likely scar tissue. I tried a full leg cast that had hand cranks built in to it to try and turn the knobs and bend the leg. That did not work. What ultimately ended up working was when I jumped up to catch a football one day and landed and felt a pop (no real pain as I remember). Within a week after that pop sensation, I was 0-90 or so. Over time, I gained additional ROM and landed somewhere between 0-110. I would have liked to get to that 130 range, but 0-110 is much better than my initial 15-50 ROM that basically equated to a frozen leg joint.
A bit long-winded, but it was quite the experience and a very long road to recovery. All said, I think it took somewhere close to 18 months for me to get to that 0-110 range.