New knee treatment tests use of patient's own cartilage cells

ORANGE, Calif. (KABC) -- The cartilage around your knee allows it to glide smoothly as you bend and straighten, but once it's torn it can cause excruciating pain. Local doctors are now investigating a new way to regenerate cartilage in hopes to make your knee as good as new.

Several months ago, 49-year-old Bjorn Borell of Orange was working out when he heard a "pop" in his right knee.

"I still feel it a little bit in the back," he said as he pointed to the soreness.

He recalled his knee had swollen and he thought that maybe he pulled a muscle.

Borell didn't pull a muscle - he tore his cartilage.

Exams soon revealed pothole-shaped indentations in the connective tissue surrounding his knee.

Holding a model of a knee, orthopedic surgeon Dr. Robert Grumet of Hoag Orthopedic Institute described that as the knee cap tracks back and forth over the femur bone, "it drives into the pothole injury and it causes friction and pain."

Grumet said the conventional way of treating this is to drill microfractures into the knee bone which creates scarring, but it's not a long-term fix.

"That cartilage would then be what they call fibro-cartilage, which is like a scar tissue basically that grows in there," said Grumet. It may have to be redone every 10 to 15 years.

Grumet and his colleagues are participating in a new study to investigate how to fill these potholes with a patient's own cartilage cells.

The two-part procedure, called NeoCart, involves harvesting tissue from the patient's knee cartilage. It's grown and processed in the lab. The finished membrane is then fitted into the damaged cartilage like patching potholes in a road.

"We can put that membrane back into that pothole of cartilage to try to restore the normal anatomy," Grumet explained.

After surgery, patients have to remain off their knee for about six weeks. The next step is physical therapy and hopefully a return to normal function.

Three months after surgery, Borell said he is not running yet, but he hopes to return to more activities in the coming weeks.

This treatment is not suited for people with advanced arthritis, in which the cartilage is completely gone.

Grumet is actively looking for patients to participate in the NeoCart Clinical trial. All study-related surgical procedures, office visits and some rehabilitation costs will be paid by the trial sponsor, Histogenics.

"If this is an option for people, they should consider this," Borell said.

For more information on the clinical trial go to or call (949) 431-7555.
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