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YOUR HEALTH: You can grow your own cartilage

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LOS ANGELES, California –  "I am back to unlimited walking, unlimited hiking, so my husband and I are getting up to the mountain and getting on some trails, which is really nice."

Karen Mohr was one of the first in the United States to get the MACI procedure last year, after damaging cartilage in her knee during an ultra-marathon.

MACI stands for Matrix-induced Autologous Chondrocyte Implantation.

First, surgeon Michael Banffy biopsied Karen's cartilage cells, sent them to a lab to be grown on a matrix for four weeks.

Then, in the main surgery, he defined the size of the damage.

"Once that's defined, I can take a template, typically some sort of sterile foil, and then from that sterile foil, I can cut the actual membrane to size and then glue that in with something called fibrin glue," explained Dr. Banffy, Orthopedic Sports Medicine and Joint Preservation specialist with the Kerlan-Jobe Institute.

Dr. Banffy says the cells start to make themselves at home quickly.

"It's almost immediate. You know, within sixty minutes, there are cells that have already adhered down to the bone below. so it occurs very quickly."

Rehab, on the other hand, will take a year.

The cartilage cells need time to mature.    Trying to do too much too soon could do more damage.

"There's nothing I can do to speed it up," said Karen.

"My best chance is to be patient and follow the protocol exactly as described, and then hopefully, when one year comes, my knee is ready."

Karen hopes to be running in the mountains again this fall.

BACKGROUND:   Knee replacement surgery, also known as knee arthroplasty, can help relieve pain and restore function in severely diseased knee joints.   The most common reason for knee replacement surgery is to relieve severe pain caused by osteoarthritis.   People who need knee replacement surgery usually have problems walking, climbing stairs, and getting in and out of chairs.   Some also have knee pain at rest.   The procedure involves cutting away damaged bone and cartilage from the thighbone, shinbone and kneecap and replacing it with an artificial joint (prosthesis) made of metal alloys, high-grade plastics and polymers.   In determining whether a knee replacement is the right choice, an orthopedic surgeon assesses the knee's range of motion, stability and strength. X-rays help determine the extent of damage. (Source:

If this story has impacted your life or prompted you or someone you know to seek or change treatments, please let us know by contacting Jim Mertens at or Marjorie Bekaert Thomas at

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