Biologic Knee Replacement: Articular Cartilage Paste Grafting

Description: Kevin R. Stone, M.D., talks about current thoughts on articular cartilage damage and repair, and discusses the Biologic Knee Reconstruction program at The Stone Clinic. 6.0 minutes/8.1MB

This is Dr. Kevin Stone answering question about articular cartilage injuries, specifically related to chondroplasty, microfracture, and articular cartilage paste grafting. Articular cartilage is the covering of the bones inside of the joint. If you crack open a chicken wing, the white shiny surface is the articular cartilage. The fibrous meniscus cartilage is the shock absorber inside the knee that helps protect the articular cartilage, the bearing surface of the joint. Sports injury that injures the articular cartilage, or when you get traumatic or osteoarthritis, the articular cartilage is damaged and sometimes it is damaged all the way down to the bone.

When we look into a joint to repair it, our choices are to smooth the rough edges around the cartilage injury or stimulate the repair progress. We do this by smoothing the edges with a shaver or sometimes with a low-level heating device. We stimulate a repair process by making multiple holes in the exposed bone in order to bring out the stem cells from the marrow, called mesenchymal stem cells, and have those stem cells, those marrow cells, form a clot on top of the injured articular cartilage. Then, by applying a CPM machine or continuous passive motion machine, we can stimulate those cells to form a new cartilage repair surface. It is not a normal cartilage repair surface, but the repair tissue is usually good enough to permit sports.

When the articular cartilage lesion is very large, or when there is a setting of arthritis, then just stimulating the marrow allow sometimes is not enough. In those cases, we perform an articular cartilage paste graft, where we take bone and cartilage from the intercondylar notch of the knee, that is, the hole that the ACL goes through, take it out of the knee and smash it into a paste. Then we bloody the base of the articular cartilage lesion and then we pack this new paste which is filled with large chondrocytes and marrow stem cells into the articular cartilage defect, just like grouting a hole in the wall. We fill this defect and we call that an Articular Cartilage Paste graft.

Articular cartilage paste grafting is indicated for patients from early on in their teenage years when they might injure their knee, to patients in their 70s who might have been told they need to have a partial knee replacement, or even a total knee replacement. Articular cartilage paste grafting is indicated when there is a chondral lesion or articular cartilage lesion or when there is arthritis. Alternative procedures such as microfracture, mosaicplasty, oats procedures, or ACI procedures, are also procedures for articular cartilage lesions, but usually are more effective when there is an isolated chondral lesion rather than an arthritic knee.

We have found many times by grafting these arthritic areas we can prolong the life of the knee and delay or avoid the joint replacement in many instances. The rehabilitation program after articular cartilage paste grafting is extremely important. Most of the time, patients use crutches for one month, a continuous motion machine, and a specific exercise program that is posted on our website. We have now done Paste Grafting since 1991, in hundreds of patients and performed second look arthroscopies with biopsies to prove that the articular cartilage repair tissue is strong tissue and able to withstand forces of now up to 15 years of people playing sports on these repaired tissues. We are able to extend the life of these repaired tissues in peoples’ knees by replacing the meniscus cartilage if that is missing and by reconstructing the cruciate ligaments or the other ligaments around the knee if the knee itself is unstable. When we rebuild knees like this, we call it biologic knee replacement where we are reconstructing and replacing the damaged tissues with biologic tissues rather than with artificial tissues. For more information about each of these procedures, we have posted a video on the website stoneclinic.com, for you to look at the actual surgical techniques and the outcomes, and we have posted our peer reviewed, published articles on the outcomes of these procedures on that website as well.

The Stone Clinic in San Francisco concentrates on returning injured people to their active lives, fitter, faster, and stronger than they were before. The Stone Clinic includes Dr. Kevin Stone, physician and surgeon, a staff of physical therapists, and an x-ray and MRI facility. Our specialties include the treatment of joint injuries and arthritis with leading edge surgical and rehabilitation techniques. Elite athletes and everyday people alike come to The Stone Clinic from around the world for the best in orthopaedic care. The Stone Clinic is located at 3727 Buchanan St., San Francisco, CA 94123. For more information, please call us at (415) 563-3110 or visit us at www.stoneclinic.com.