Microfracture surgery

Microfracture surgery is an articular cartilage repair surgical technique that works by creating tiny fractures in the underlying bone. This causes new cartilage to develop from a so-called super-clot. Microfracture surgery has gained popularity in sports in recent years; numerous professional athletes including members of the NBA (most notably Andrew Bogut, Anfernee Hardaway, Jason Kidd, Greg Oden, Allan Houston, Kenyon Martin, Tracy McGrady, Chris Webber, and Amar'e Stoudemire), MLB (Jeff Clement, Matt Kemp, and Derek Holland),NFL, and NHL have undergone the procedure.

The surgery is quick (typically lasting between 30–90 minutes), minimally invasive, and can have a significantly shorter recovery time than an arthroplasty (knee replacement).

Chronic articular cartilage defects do not heal spontaneously. However, acute traumatic osteochondral lesions or surgically created lesions extending into subchondral bone, e.g. by Pridie drilling, spongialization abrasion or microfracture causing the release of multipotent mesenchymal stem cells from the bone marrow, may heal with repair tissue consisting of fibrous tissue, fibrocartilage or hyaline-like cartilage. The quality of the repair tissue after these "bone marrow stimulating techniques" depends on various factors including the species and age of the individual, the size and localization of the articular cartilage defect, the surgical technique, e.g., how the subchondral bone plate is treated, and the postoperative rehabilitation protocol.

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