SNOWMASS, COLO. – A novel approach to repairing anterior cruciate ligament injuries – and perhaps thereby avoiding a downstream tidal wave of knee osteoarthritis – is creating major buzz in sports medicine circles.
“You’ll probably hear much more about this bioenhanced repair, with the expectation of achieving strength equal to that of ACL reconstruction and perhaps preventing the development of osteoarthritis 15 years down the road,” Dr. M. Timothy Hresko predicted at the Winter Rheumatology Symposium sponsored by the American College of Rheumatology.
He cited research led by his colleague Dr. Martha M. Murray of Boston Children’s Hospital, which has resulted in development of a surgical technique combining a tissue-engineered composite scaffold with a suture repair of the torn ACL in what Dr. Murray has termed a bioenhanced repair.
Her work, to date preclinical, has garnered major awards from both the American Orthopaedic Society for Sports Medicine and the American Academy of Orthopaedic Surgeons. The Food and Drug Administration recently granted approval for the first clinical safety studies, to begin this year.
There is a major unmet need for better methods of repairing ACL injuries. They’re common, with an estimated 550,000 cases per year. The peak incidence occurs in 15- to 19-year-old female athletes. And the current gold standard therapy consisting of ACL reconstruction using an allograft or hamstring graft has a disturbingly high failure rate, both early and late. The graft failure rate is up to 20% in the first 2 years, climbing to 50% at 10 years.
“We just have to do better,” conceded Dr. Hresko, an orthopedic surgeon at Harvard Medical School, Boston, and Boston Children’s Hospital.
“One of the interesting and unfortunate facts,” he continued, “is that roughly 80% of people who have an ACL injury, with or without reconstruction, are still going to have osteoarthritis 14 years after the injury. So, if this is your 15-year-old daughter who plays basketball, she’ll only be 30 and will already have degenerative arthritis of the knee at what should still be a very active period of life.”
The bioenhanced repair now under study uses an extracellular matrix-based scaffold, which is loaded with a few milliliters of the patient’s own platelet-enriched plasma. The scaffold is applied between the torn ligament ends in order to stimulate collagen production and promote ligament healing. The suture repair of the ligament entails much less trauma than does standard reconstructive surgery.
In large-animal studies, the bioenhanced repair resulted in the same yield load, stiffness, and other desirable biomechanical properties at 1 year as with major reconstructive surgery. However, while premature posttraumatic osteoarthritis occurred in 80% of the knees treated with standard ACL reconstruction, there was no evidence of such damage 1 year following bioenhanced repair. Nor have adverse reactions to the scaffold been noted in the porcine model.
Dr. Hresko reported serving as a consultant to Depuy Spine.