I'm now 7 months and 2 weeks post m/f medial femoral subcondyle; 1.5 x 1.0cm lesion.
I was on crutches with no weight bearing for just over 5 weeks (I did some very light touch down with my affected leg in the days leading up to coming off the crutches). I was in the middle of a holiday in Portugal when I had to come off the crutches. I more or less just ditched them altogether and started to walk. It was quite painful and hard work. I spent a lof of time in the swimming pool walking about as that takes a lot of your body weight away for you.
I started on the bike in the gym 2 weeks after the operation with no resistance and slowly and started bulding up the resistance after 7 weeks. I did straight leg raises with no weights to try and rebuild the muscles before adding weights (you can stick a can of soup in a sock for example and tie in round your ankle). I'm now doing lunges with weights, squats, dead lifts, using the leg extension machine and calf dips plus doing the bike.
The muscles of my affected leg are still noticeably smaller than the good leg so it takes a long long time to get muscle back.
As for the injury itself, I've noticed some improvement but not a lot. To be honest, I don't think its worked for me and I'm just treading water before needing another operation in June, possibly a mosaicoplasty.
Best of luck, its a long, hard and very depressing road!