Kevin Stone, MD

Dr. Kevin Stone: Shifting From Bionic to Biologic Replacement

December 09, 2009

Kevin R. Stone, M.D. is an orthopaedic surgeon in San Francisco who specializes in sports injuries, particularly those of the knee and shoulder. He is recognized internationally as an authority on cartilage growth, replacement, and repair. He is a founder and chairman of the Stone Research Foundation and The Stone Clinic, a leading center for treatment of athletes with joint injuries.

Dr. Stone has been a physician for the U.S. Ski Team and the World Professional Ski Tour. He has also been a physician for the U.S. Olympic Training Center, the U.S. Olympic Festival, the International Winter Special Olympics, the Smuin Ballet and other numerous sports and dance organizations.

Dr. Stone received a A.B. from Harvard College and an M.D. from the University of North Carolina School of Medicine. He completed his internship in internal medicine at Harvard's Beth Israel Hospital, a general surgery residency year at Stanford University Hospital and an orthopaedic residency at the Harvard combined Orthopedic Residency Program

Over the past ten years, great strides have been made in the field of orthopaedic surgery. Research conducted in the past decade has helped scientists in the field gain a better understanding of knee anatomy, treatment, and care. Dr. Kevin Stone notes that one of the biggest and most notable developments made in orthopedics is portrayed in the shift from the bionic (artificial) to biologic replacement of arthritic joints.


Dr. Kevin R. Stone discusses: Developments in Meniscus Cartilage Repair:

Developments in articular cartilage repair:

The shift from Bionic to Biologic Replacement of Arthritic Joints:

Alternative Therapies for Knee Care:

Benefits of JointJuice:
In the past, when the bionic replacement of joints had dominated the field, “arthritic patients were always told to rest their knee and wait for a Total Knee Replacement (TKR),” explains Dr. Stone, whereas “now, what we are telling people is that in fact, exercise and activity are very good for arthritic knees and we can rebuild the missing cartilage and replace the missing meniscus in an outpatient arthroscopic procedure.” This focus on biologic replacement gives patients with arthritis relief from pain and improved function to help them delay the time in which a joint arthroplasty is required.

The shift in focus to the biologic replacement of joints has also led to a change in focus on how each tissue is treated and addressed.

Meniscus Cartilage

To begin, Dr. Stone talks about the meniscus cartilage. In the past, options for surgeons had been limited to meniscectomy, and sometimes, meniscus repairs. However, the introduction of collagen-meniscus implants like the Menaflex device, manufactured by ReGen Biologics, Inc., has permitted the development of a whole new field of meniscus reconstruction. Invented by Dr. Stone in the mid-1980s, the Menaflex meniscal repair device was approved by the Food and Drug Association (FDA) for use in the U.S. at the end of last year.

He explains that while in the past, “surgeons’ options were either a meniscectomy, where they took out part of the torn meniscus, or sometimes a meniscus repair”, the FDA approval of the Menaflex device has provided surgeons encountering patients with partially missing meniscus cartilage the options to “reconstruct it with a meniscus-collagen implant; or if the meniscus is completely missing, they can replace it with a meniscus allograft.”

Articular Cartilage

In terms of the articular cartilage, Dr. Stone explains that the past provided surgeons with limited options of chondroplasty or microfracture for the treatment and repair of articular injury. Unfortunately, many patients’ microfractures or chondroplasties failed, requiring another procedure for the re-growth of the articular cartilage surface. Recent developments in orthopaedics however show that when an articular cartilage paste graft is performed, the patient’s own stem cells are being transplanted, which allows for the re-growth of that articular cartilage surface, “not to normal cartilage, but to very good repair tissue.”


On the ligament side, the focus on rebuilding was for young people. Recent research shows that the use of sterilized bone-patellar tendon-bone allograft allows for ligaments to be reconstructed in older people who have knee instability but want to remain active as well. “Because the morbidity of the allograft procedure is so much lower, patients are able to recover quicker and return to activities,” Dr. Stone explains, which makes this an ideal option for most peopl.

“So the whole field of the biologic knee replacement, of replacing the meniscus, grafting the articular cartilage, [and] rebuilding the ligaments has completely evolved,” Dr. Stone says.

The Menaflex Controversy

When asked for his thoughts on the controversy of the Menaflex device, Dr. Stone defended the Menaflex device, highlighting that the controversy is only related to the FDA approval process and that the actual device has “never been shown to cause any problem at all.” He states that there is “pretty good long term data” about the efficacy of the product, and that while the controversy “highlighted how long it takes to get approval from the FDA and the problems with that process, it didn’t say anything about the device itself.”

Post-Operative Suggestions

Despite all the great strides that have been achieved in the field of orthopaedics however, one thing seems to remain the same. That is, the scores of patients who undergo surgery, only to be back in the hospital a few months later because their injuries had not healed properly. When asked what he felt was the most common post-operative mistakes that patients make after undergoing knee surgery, Dr. Stone simply stated that they don’t do enough. They don't get enough physical therapy and fitness training. "Most patients either rest their injured knee or see themselves as a patient in rehabilitation as opposed to an athlete in training.”

Encouraging the idea that patients should always try to remain active, Dr. Stone explains that “if we can encourage patients to see themselves as an athlete in training and train around the injured joint, train the cardiovascular system, and work on their upper-body muscular development during the recovery phase, they tend to have a much faster recovery.” This sounds like good advice for anyone recovering from a knee injury.

Read Dr. Kevin Stone’s Hero Interview on Cartilage Growth and Repair

Discuss Rheumatoid Arthritis in our Forums.

Discuss Rehabilitation and Treatment in our Forums.

Discuss Meniscus Injury and Repair in our Forums.

Discuss Microfracture in our Forums.

Discuss Ligament Damage in our Forums.

Discuss Arthroplasty in our Forums.

Discuss Joint Care in our Forums.



Last updated: 09-Dec-09

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