Cartilage Regeneration and Osteoarthritis

Cartilage regeneration attempts to restore damaged articular (joint) cartilage. Several techniques have been used for cartilage regeneration. While some of these are being used today, researchers continue to look into new ways to regrow cartilage in an attempt to give people relief from the pain of osteoarthritis.

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What Is Articular Cartilage?

The matrix of cartilage is made up of collagens, proteoglycans, and non-collagenous proteins. While cartilage is a highly-organized structure, about 85% of cartilage is water. This decreases to about 70% of older people. Chondrocytes are the only cells found in cartilage and this produces and maintains the cartilage matrix.

Articular cartilage serves as the cushion and shock absorber within the joint. It does so because it lines the ends of the two bones that form the joint.

Cartilage damage can be caused by several conditions including:

Joints affected by cartilage damage become painful, stiff, and have a limited range of motion.

Cartilage has a limited capacity to heal itself. Consequently, articular cartilage has become the focus of many researchers and tissue engineers who strive to be able to grow new cartilage and transplant it in place of damaged or worn cartilage.

Progress With Cartilage Regeneration

Several techniques have been developed that show progress in cartilage regeneration.

  • Debridement or abrasion: A surgeon arthroscopically removes loose cartilage which causes bleeding at the bone surface and growth of fibrocartilage (fibrous cartilage or scar tissue). In some cases, the fibrocartilage may not be strong enough to effectively protect the joint.
  • Microfracture: A surgeon arthroscopically clears the affected area and makes several perforations in the bone. This is designed to stimulate bleeding and growth of fibrocartilage as well.
  • Mosaicplasty or osteochondral autograft transplantation surgery: A surgeon removes a plug of bone with cartilage covering a healthy area of the joint and transplants it to the damaged area.
  • Periosteal flap: A surgeon removes a portion of the periosteum (the connective tissue covering all bones) from the shin and transplants it to the area of cartilage damage.
  • Autologous Chondrocyte Implantation (ACI): A surgeon arthroscopically removes a small portion of cartilage from the knee. The tissue is then sent to a lab to be cultured. A second surgery is required so the lab-grown cells can be implanted at the site of the damaged cartilage.
  • Osteochondral allografts: A donor's bone is used to repair the damaged cartilage.
  • Matrix Associated Chondrocyte Implantation (MACI): The Food and Drug Administration approved this procedure in 2017 for people under 55 with "focal chondral defects"—lesions that can lead to osteoarthritis of the knee. It is similar to ACI but requires less invasive surgery and the chondrocytes are shipped back to the surgeon on a patch that acts as a scaffold over the damaged area.

All of the procedures yield mixed results. There are still many questions that plague attempts at cartilage regeneration.

More clinical trials are needed to find definitive answers and to develop procedures that relieve arthritis symptoms and produce a durable replacement for damaged cartilage.

Research Continues

The challenge of coming up with a better solution for cartilage regeneration is on the minds of many researchers. Throughout the world, new research and techniques continue to look into this matter and the early results look promising.

For instance, in 2008, bioengineers at Rice University discovered that intense pressure (comparable to that found over half a mile below the surface of the ocean) stimulates cartilage cells to grow new tissue. This new tissue possesses nearly all of the properties of natural cartilage.

The researchers believe this development holds promise for arthritis treatment. The lead researcher forewarned that it will be several years before the process would be ready for clinical testing in humans.

Stem cells are also being used to grow new cartilage for arthritic hips in a technique being developed at Washington University School of Medicine as of 2017. In partnership with Cytex Therapeutics, the hope of these researchers is that this will become an alternative to hip replacement surgery.

This technique shows the most promise for those under 50. It uses a "3-D, biodegradable synthetic scaffold" and essentially resurfaces the hip joint to ease pain. It may delay, if not eliminate, the need for a new hip.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Li Y, Wei X, Zhou J, Wei L. The age-related changes in cartilage and osteoarthritis. Biomed Res Int. 2013;2013:916530. doi:10.1155/2013/916530

  2. International Cartilage Regeneration and Joint Preservation Society (ICRS). What is a cartilage damage?

  3. Kock L, Van donkelaar CC, Ito K. Tissue engineering of functional articular cartilage: the current status. Cell Tissue Res. 2012;347(3):613-27. doi:10.1007/s00441-011-1243-1

  4. Food and Drug Administration. FDA approves first autologous cellularized scaffold for the repair of cartilage defects of the knee. December 13, 2016.

  5. Boyd J. Cartilage regeneration '20,000 Leagues Under the Sea'. Rice University. 2008.

  6. Washington University School of Medicine in St. Louis. Stem cells engineered to grow cartilage, fight inflammation. July 18, 2016.

Additional Reading

By Carol Eustice
Carol Eustice is a writer who covers arthritis and chronic illness. She is the author of "The Everything Health Guide to Arthritis."