Failure of these tissues to heal has been known by orthopedists for almost thirty years (8,16). Traditionally these injuries have been treated with either simple excision of the tissue (7) or replacement with autograft or allograft tissue (5).

Unfortunately, neither removal nor replacement prevents the premature onset of osteoarthritis (7,15,18) (Fig. 2). Current treatment methods, for those who sustain ACL injuries in the US each year, has shown to result in premature osteoarthritis in 70% of patients at only 14 years after injury (18). Rates of premature osteoarthritis after meniscectomy approach 50% at 12 years (11), and reach as high as 87% at 16 years when the meniscus is removed in children (6).

We seek new ways to effectively treat these injuries, and to help prevent young patients with these injuries from developing a disease of old age in their twenties and thirties.

Why is there a failure of healing for tissues inside joints?

• Rotator cuff fails to heal over 90% of the time after suture repair (10).
• Meniscus fails to heal after suture repair at least 40% of the time, even in the small proportion of tears selected carefully as the best suture repair candidates (12,17).
• Articular cartilage injuries have a limited healing response with or without debridement, and have only a limited healing response even with the addition of transplanted cells (13).