Ask a Vail Sports Doc column: Cartilage restoration techniques for the knee
Ask a Vail Sports Doc
Residents and visitors to the Vail Valley like to play hard, whether it be tracking one’s vertical feet on a powder day or participating in the Vail Hill Climb.
I think it is great to be active and push one’s limits beyond what we might have thought ourselves capable of. As we get older, most of us confront some “wear and tear” arthritis issues, myself included. One of the more common places to develop arthritis is in the knee, particularly under the knee cap, or in what is known as the patellofemoral joint.
Osteoarthritis is a process in which there is a loss of articular cartilage. I explain to my patients that articular cartilage is the white coating cartilage you would see on the end of a chicken bone. We have the same sort of cartilage on the ends of our bones.
When you wear this cartilage down, much like wearing the tread down on your tires, you have osteoarthritis or “wear and tear” arthritis. I tell my patients that restoring lost coating cartilage to our joints is the Holy Grail of orthopedics. We are not there yet, but we continue to make advances in the field of regenerative medicine.
Many patients are under the impression that they can have stem cells injected into their knees and new cartilage will grow and their arthritis will be cured. Unfortunately, that is not true as of today. Sadly, there are some unscrupulous practitioners out there who will gladly charge you a lot of money and suggest as much. However, I increasingly utilize stem cells and platelet rich plasma injections given growing evidence of its efficacy in the orthopedic literature. Stem cell injections and PRP injections can definitely modulate and help control the symptoms of arthritis (please see my recent article on regenerative medicine), but not cure it as of 2017.
For patients who have failed non-surgical management of their arthritis, who suffer from significant pain and/or swelling, and who are no longer able to do the activities they enjoy, there are better surgical options than there were in the past to treat cartilage defects.
Autologous chondrocyte implantation is the most well established and widely used biologic cartilage cell transplantation technique. I have some patients who are 10-plus years out from this surgery and exhibit minimal cartilage wear.
In this technique, two Tic Tac size pieces of bone and overlying cartilage are harvested from the edges of the knee joint. The cells are sent for culture and the chondrocytes (articular cartilage cells) are expanded. The FDA recently permitted an exciting advancement in the technique whereby the cells are seeded onto a 3-D biologic scaffold and then this is implanted into the defect.
Osteochondral transplantation is a technique in which a core of normal cartilage and underlying bone is taken from a non-weightbearing portion of the knee or taken from a donor knee. The area of worn cartilage and an equal amount of bone is removed from the patient’s knee with a coring device and the new cartilage and bone is implanted in the defect. With patients, I liken it to moving the hole on a putting green from one place to another and putting new grass where there once was dirt.
Of these two techniques, I typically recommend autologous chondrocyte implantation in those patients who are candidates as the underlying bone is not violated, normal areas of cartilage in the knee are not disturbed, the normal contours of the cartilage can be better reproduced, and the cartilage cells are more viable compared to the osteochondral transplantation technique which utilizes donor cartilage cells.
Dr. Rick Cunningham is a knee and shoulder sports medicine specialist with Vail-Summit Orthopaedics. He is a physician for the U.S. Ski Team. Do you have a sports medicine question you’d like him to answer in this column? Visit his website at http://www.vailknee.com to submit your topic idea. For more information about Vail-Summit Orthopaedics, visit http://www.vsortho.com.