Case study: Use of platelet-rich plasma and bone marrow aspirate concentrate injections to treat knee osteoarthritis

April 21, 2018

The patient is a fit 83-year-old who, as a former flight attendant, is used to being on her feet. In 2014, she presented with osteoarthritis pain that started to affect her left knee and threatened her mobility, and she was searching for treatments that wouldn't interfere with her active lifestyle.

In January 2015, the patient had received two separate injections of platelet-rich plasma (PRP). The PRP injections alone did not provide adequate symptom relief. In July, she received an injection of bone marrow aspirate concentrate (BMAC) and PRP.

Jay Smith, M.D., a physiatrist and the director of Regenerative Medicine within the Rehabilitation Medicine Research Center at Mayo Clinic's campus in Rochester, Minnesota, evaluated the patient and administered the BMAC and PRP injections. To date, Dr. Smith and colleagues at Mayo have administered PRP or BMAC injections in more than 400 patients. Current scientific literature indicates that between 40 and 70 percent of individuals who receive this treatment find some level of pain relief, according to Dr. Smith. "It doesn't work 100 percent of the time," he says. "But we have a pretty good success rate when the primary goal is to improve symptoms and allow patients to do the things they want to do."

Dr. Smith says that a portion of the conversation he has with patients is that regenerative medicine strives to restore health by harnessing the body's natural ability to heal itself. "We tell our patients that it's an acceptably safe orthopedic procedure, and it may or may not modify their level of pain," Dr. Smith says.

What is known about the treatments is that they most likely lessen the inflammatory process caused by degrading joint cartilage. "Treatment with PRP is built upon the knowledge that platelets carry a multitude of growth factors," Dr. Smith says. "They are the first responder cells when we get injured, and they control the damage and start the healing process."

For PRP therapy, platelets are extracted from a vein in the patient's arm and concentrated using a centrifuge. The concentrate is then injected back into the patient's joint, where the growth factors mitigate inflammation.

BMAC contains not only platelets but also a variety of other powerful cells, including stem cells. Stem cells also have significant anti-inflammatory properties and can powerfully influence other cells involved in inflammation and healing. They also have the ability to become other types of cells. The bone marrow is drawn from a patient's pelvic bone, concentrated in a centrifuge and then injected into the problematic area. "The bone marrow concentrate and platelet rich plasma very naturally modify the inflammatory and immune response," Dr. Smith says.

A few hours after receiving treatment, the patient walked out of the procedure room with the aid of crutches and a knee brace, which she used for one week. The patient indicated that the injections eased the pain enough for her to return to her previous level of activity.

Dr. Smith notes that the patient's overall health contributed to the treatment's chance of success.

"One of the things I feel is relevant to her success is that she's very healthy," Dr. Smith says. "We are working with biologic products. They are only as healthy as the people they come from. I strongly believe that the healthier you are, the more likely these treatments are to succeed."

PRP and BMAC are not yet approved by the Food and Drug Administration (FDA) for use in treating osteoarthritis pain and therefore are typically not covered by insurance. In addition to treating patients with PRP and BMAC, Dr. Smith and colleagues are conducting FDA-approved clinical trials on the use of purified stem cells to treat knee arthritis. And researchers at Mayo Clinic's campus in Jacksonville, Florida, are conducting clinical trials comparing conventional PRP treatment with concentrated bone marrow stem cell injections for osteoarthritis of the knee.

For more information

A Study of the Safety and Usability of Culture Expanded STEM Cells Derived from the Patient's Own Fat Tissue for Treatment of Knee Osteoarthritis. Mayo Clinic.

Conventional Platelet-Rich Plasma Versus Concentrated Bone Marrow Stem Cell Injections for Osteoarthritis of the Knee Mayo Clinic.