Since the 1970s, cartilage grafts have been used routinely for joint replacement. But with limited success.
The old method of preserving cadaver cartilage by freezing many times weakened specimens, resulting in bad transplants.
The newer approach of preserving cartilage in a solution was more successful. But the tissue degraded significantly after a few weeks and was unusable after a month. To maximize success, doctors had to perform graft surgery within about three weeks of specimen donation.
Indeed, about 80 percent of donated tissue has to be discarded before being transplanted due to its short shelf life.
The Discovery
In March, MU scientists announced that, after five years of lab research, they had created a storage solution that increases cartilage preservation to more than two months.
The storage solution, currently called the Mizzou Tissue Preservation System, can be tested to measure the level of cartilage degradation, thereby reducing the chances of a bad transplant.
“The solution has increased the quality of the grafts, and we can test the quality of the solution to reduce the possibility of transplanting a poor graft,” said James L. Cook, an MU researcher in veterinary medicine and professor of orthopedic surgery.
Joint tissue is used to rebuild knees, hips, shoulders, hands and ankles. Studies show that the transplants last at least 15 years.
The Application
The Mizzou solution preserves tissue for up to 63 days, studies show, while maintaining almost all of the tissue’s integrity.
“This is important because the quality of the tissue at the time of a transplant procedure markedly affects long-term success for the patient,” said Cook, the lead researcher in the Mizzou Tissue Preservation System.
Unlike those involving body organs, cartilage transplants run no risk of rejection because the body’s immune system can’t penetrate its density, Cook said.
The tissue solution was first used to preserve cartilage transplanted into rodents, rabbits and about 15 dogs before being tested on human cancer patients.
Mizzou is receiving bids for the licensing rights of the preservation system from three major tissue banks, Cook said. Most of the royalties for the system will go to the university.
The storage system should be in orthopedic clinics, including the Missouri Orthopaedic Institute in Columbia, sometime next year.