The slowed osteoarthritis process seen in the pig knees may also result from saving the original ACL and its nerve fibers, says Murray.  “The nerves may survive, generating new fibers in the scar tissue.  So the knees may not get OA because the nerves can still send messages to muscles that help stabilize the knee.” Stabilizing the knee reduces pressure on the joint and lessens the risk of OA.

Murray hopes to begin a human trial in 2014.

What the Findings Will Mean for Osteoarthritis Therapy

Dr. Rodeo warns that this research is still early. However, “if we can identify markers that are predictive of progressive changes, then we may know which patients are more at risk,” he adds. “Such markers may be able to help us evaluate who responds to treatment.”

Once markers are identified and followed, researchers can expand the study, following markers in a large number of patients. “As we follow patients, we’ll look at whether a marker is predictive of how a person does over time, and what happens to those who have the marker and those who don’t,” says Dr. Rodeo.  “And we can use the [fluctuation] of a marker to evaluate new treatments, asking, ‘Is the marker going down or up?’”

The study is not about finding a cure, emphasizes Dr. Stuart:  “But it will set the stage for future research that may contribute to our understanding of why OA occurs and contribute to our ability to slow its progress.”