Brief Procedure Repairs Knees

or athletes or accident victims with damaged knees, or people suffering from focal arthritis in the knee, typically the only way to restore mobility has been through a colossal operation to replace the ragged joint. Physicians, how-ever, have been well aware that when the injury is limited to one area, surgery could be avoided if a small amount of the remaining healthy bone or cartilage were prompted to grow back normally.

Now, a procedure offered by orthopedic surgeons David Hungerford, M.D., Dennis Lennox, M.D., and Michael Mont, M.D., is making that possible. Many cases of knee trauma—resulting from conditions as common as the tiny lesions caused by early arthritis to injuries as dramatic as gunshot wounds—respond well to a technique called O.A.T.S.—for osteochondral articular transplant system, a new way to replace lost joint tissue.

Conceived in Europe, the technique has been followed for nearly a decade, with reports of a success rate greater than 90 percent. Since last year, the surgical team here has begun using O.A.T.S. on a trial basis and has already operated on 15 patients. The procedure takes place in a single, hour-long outpatient visit. Depending on the size of the injured area, patients receive either a spinal or local anesthetic. Then, with a simple tool much like an apple corer, the surgeon removes several small plugs of cartilage and bone (eight to 10 millimeters in diameter and up to 15 millimeters deep) from healthy, non-weight-bearing parts of the patient’s knee. The plugs then are transplanted in the tissue at the damaged area. During the next few weeks, as the implantation takes, the bony tissue heals with the help of nearby blood vessels and the cartilage is nourished from the joint fluid. Within a month and a half, many patients are able to bear weight on the joint, progressing to full weight a month or so later.

O.A.T.S. has distinct advantages that set it apart, notes Lennox. “We do both parts of the procedure in one visit. Patients don’t have to go through two operations—as with other implantation operations where the tissue first is harvested, then grown in the lab, and finally implanted during a second visit.” The team is now setting up prospective, randomized studies of O.A.T.S. States Lennox: “For young, active people, it’s a highly promising alternative to knee replacement.”