Rationale for the procedure
By poking tiny holes (nanofracture) through the cartilage defect and into the subchondral plate separating it from the bone local bleeding is produced.
The blood flow will bring stem cells into the area to regenerate the cartilage (chondrogenesis).
The surgeon then covers the whole defect and the bleeding holes with a collagen membrane which is cut to shape and glued in with fibrin glue.