On my ankle op report it states "osteochondral defect was very atrophic with no fibrocartilage in its base." i'm trying to figure out the meaning. thx?

Missing cartilage: Cartilage is the bearing surface that allows your joints to move smooth and painlessly. "Osteochondral defect" means that not only was there an area found without cartilage but there was some bone missing as well. That there it had no "fibrocartilage " would indicate the body had not tried to repair it at all by producing scar tissue.