Battling severe arthritis, Charlotte Marsden had a total knee replacement scheduled for last September. The pain was so bad that Marsden, 61, couldn’t endure walking on concrete floors or on the beach near her Cape May, N.J. home. In a last-ditch effort to avoid surgery, she tried an increasingly popular procedure – platelet-rich plasma therapy, which included injections of her own concentrated platelets, protein-releasing bodies that help heal wounds.

Now, after the platelet therapy, Marsden, says she can again work in her garden, climb steps, ride a bike – and walk anywhere. Platelet injections also eased the pain in her shoulder and big toe.   

“I’m pain-free after 15 to 20 years of suffering,” she says.

The platelet-rich plasma therapy, or PRP, procedure takes a small amount of a patient’s blood and rotates it in a centrifuge to separate red blood cells from platelets. Then the concentrated platelets are re-injected into the damaged area – elbows, knees, shoulders, hips and Achilles tendons. The platelets release growth factors that theoretically help the tissue recover, with the patients ideally improving within a few weeks.

Physicians report that the demand for PRP has soared after pro golfer Tiger Woods received injections to accelerate healing after knee surgery. And two Pittsburgh Steelers, Troy Polamalu and Hines Ward, had the procedure before the team’s Super Bowl victory in 2009.

But despite such positive personal stories and high-profile successes, some orthopaedic surgeons remain cautious about the spread of PRP, saying that not enough substantial research has been done on its effects to push it widely.

A study published in January 2010 in the Journal of the American Medical Association, for example, one of the first rigorous tests of this technique, found that PRP injections were no better than placebo shots of salt water for patients with Achilles tendinopathy, a condition that causes pain just above the heel bone.

“It’s clearly hyped too much,” says Stephen C. Weber, MD, an orthopaedic surgeon in Sacramento, Calif.

But others have embraced PRP, saying science simply hasn’t caught up to what they are seeing in their patients.

Platelet-rich plasma therapy represents “the beginning of a seismic change in orthopaedics,” says Rocco Monto, MD, an orthopaedic surgeon in West Tisbury, Mass. “Most of my colleagues have dipped their toes in the water and are finding early success.” 

This week, the debate will likely intensify as the results of four new studies are presented at the annual meeting of the American Academy of Orthopaedic Surgeons (AAOS) in New Orleans. The research at the AAOS conference includes three studies that show more promising results.

Dr. Monto, for example, used PRP for chronic Achilles tendonosis in patients where other treatments had failed. Nearly all showed improvement. Thirty patients with an average age of 47 had follow-up at intervals up to six months, and in the end, 28 were satisfied with the clinical results.

“At the time, it was a little shocking, how well they did,” Dr. Monto says.

Platelet-rich plasma therapy also proved better than injections of gel-like substances called hyaluronates to treat knee pain caused by osteoarthritis (OA), according to an Italian study. The trial tracked 150 participants, with 50 receiving a series of three PRP injections, 50 getting injections of high molecular weight hyaluronic acid, which was comparable to Synvisc, and the remaining 50 received a low-molecular weight hyaluronic acid, such as Hyalgan. All were evaluated at the end of six months. PRP appeared to work better than either kind of hyaluronic acid, says Elizaveta Kon, MD, an orthopaedic surgeon in Bologna, Italy, and lead author of the study. But “It’s not holy water,” Dr. Kon cautions. “You can’t use it for everything.”

In the third trial, PRP was found superior to corticosteroid treatment for patients with chronic tennis elbow, in a double-blind randomized controlled trial. The 100 patients – 51 getting PRP, and the rest receiving corticosteroids – had a follow-up after a year.

The lead author of that study, Taco Gosens, MD, of the Netherlands, says that while it’s “very healthy to be skeptical,” PRP appears to be a valid treatment for that condition.

Not all the studies were positive, however.

Dr. Weber, of Sacramento, Calif., tested the therapy in 60 people who were having minimally invasive surgery to repair torn muscles in the shoulder’s rotator cuff, a procedure known for high failure rates. Half of study participants were treated with platelets after their surgeries and the other half were not. All were treated under anesthesia, so they didn’t know if they had received platelets or not. After three months, he found no apparent differences in pain or overall results between the groups.

“It’s very enticing theoretically,” says Dr. Weber. But he cautions that “patients should be skeptical” until thorough research is done on PRP.

Eddie McDevitt, MD, an orthopaedic surgeon in Annapolis, Md., agrees. He says that PRP has potential, and says demand is high among athletes and other patients. But he also says more research is needed before he will be comfortable using PRP. “We’re always trying to help people with arthritis, but you want to do it the right way,” he says. “I want to see some more good studies.”

Another consideration is cost. The general lack of health insurance coverage for platelet-rich plasma therapy can have patients picking up the entire tab, as much as $2,000 per injection.

Charlotte Marsden says her PRP injections cost more than $10,000. She says she hopes to get some money reimbursed by her health insurer, but adds, “If I don’t get a dime back, it was worth every dollar.”