First test for plastic meniscus in U.S.

What could be a breakthrough for knee pain sufferers has gotten its first U.S. test.

Surgeons at Ohio State University Medical Center have implanted the first plastic meniscus - that's the cartilage pad between the bones in the knee.

Millions of people have a torn meniscus.

A damaged one won't repair itself, and often, gets worse over time.

The synthetic meniscus replaces the damaged one, and over time, shapes itself to the person's knee for a custom fit.

Dr. Kaeding explains, "If this implant turns out to work as well as we think it will, it fills a gap in our treatment spectrum for patients who have injuries to their knee."

Doctors hope it will not only relieve their pain, but help them delay or avoid knee replacement.

It's being tested at seven medical centers in the eastern United States.