SUBCHONDRAL DRILLING INDEPENDENT OF DRILL HOLE NUMBER IMPROVES ARTICULAR CARTILAGE REPAIR AND REDUCES SUBCHONDRAL BONE ALTERATIONS COMPARED TO DEBRIDEMENT. (April 2022) - Stachel, N.; Orth, P.; Zurakowski, D.; Menger, M.D.; Laschke, M.W.; Cucchiarini, M.; Madry, H.