My doctor says that my stage 2 &4 osteochondritis dissecans which was successfully treated with fragmetnt fixation is clinically healed. am i cured?

Hopefully yes...: Hopefully, one's problems will successfully heal after surgical internal fixation of the fragment(s). In real life, there is not a 100% success rate. One can ask his orthopedic surgeon about how often the fixation cures the problem. One website estimates 80-95% success rates.

Dr Kimm agreed

For now : Time will tell if this piece stays stable and healthy. There is always potential that it could be a problem in the future. Depending on how smooth the transitions are from the fragment to the surrounding cartilage, there may or may not be future degenerative changes that occur.