Professional athletes are getting injections of stem cells to speed up recovery from injury. Critics call it a high-tech placebo.

Elite athletes do whatever it takes to win. Lately, that?s meant getting an injection of their own stem cells.?The treatments, developed over the last eight years, typically involve extracting a small amount of a player?s fat or bone marrow and then injecting it into an injured joint or a strained tendon to encourage tissue regeneration. Bone marrow contains stem cells capable of generating new blood cells, cartilage, and bone.

NFL quarterback Peyton Manning reportedly had a stem cell treatment to his neck in 2011.

Although the treatments have become a multimillion-dollar industry, some doctors say there?s only thin medical evidence they actually speed healing. In a report issued last week, public policy researchers at Rice Quarterback Peyton Manning of the Denver BroncosUniversity criticized the National Football League?s role in promoting ?unproven? treatments to the public. Some players, including Peyton Manning of the Denver Broncos and Sidney Rice, who?s now retired but won a Super Bowl with the Seattle Seahawks last year, have reportedly gone overseas for stem cell treatments and others have acted as spokespeople for U.S. clinics offering them.?The Rice researchers, Kirstin Matthews and Maude Cuchiara, say the NFL should create an independent panel and fund research on whether stem cell treatments actually work, similar to what it did after facing questions around concussions and brain injury. ?I think they should be more proactive. They should get ahead of this one,? says Matthews.

Sports Illustrated reports that hundreds of football players have gotten stem cell treatments, with many travelling abroad for types of therapy not offered in the United States. But it?s not only football players trying them. The tennis player Rafael Nadal is reportedly undergoing stem cell treatments for back pain, and the injections are also being sought out by soccer players and high school athletes.

The NFL didn?t respond to questions from MIT Technology Review. Doctors offering the treatments say they?re promising and should be given a chance. Others say there?s not enough data. ?Any of these injections have a placebo effect,? says Freddie Fu, an orthopedic surgeon who is chairman of sports medicine at the University of Pittsburgh Medical Center and top doctor for the school?s sports teams. ?We don?t know what we are putting in. We don?t really know what exactly what it does, biologically.?

Orthopedic surgeons hope one day to use stem cells to regenerate cartilage and other lost tissue. But wishful thinking, and profits, have gotten ahead of the facts, says Fu. ?There?s a lot of marketing in orthopedics right now. I would say 15 to 20 percent of treatments are not effective,? he says.?Unlike a drug, which gets tested for years and is then weighed by experts and the U.S. Food and Drug Administration before hitting the market, the bone marrow treatments offered in the U.S. aren?t regulated.

At many private sports clinics and some academic medical centers,
such treatments have become routine. Kenneth Mautner, director of primary care sports medicine at Emory University and team physician for its athletics department, says he performs about two to four bone?marrow injections a week. ?I?ll be the first one to tell you it?s a new procedure,? he says. ?The evidence from human studies is really weak at this point.??Still, Mautner says he thinks he?s seeing success in some patients, and there is plenty of demand. ?We have patients who have the financial means, and who want to get back faster, before the literature can back it up,? he says. An injection of bone marrow for a sports injury costs about $6,000 and isn?t covered by insurance.

?Demand is exploding,? says Mitchell Sheinkop, a Chicago-area physician who says he?s injected bone marrow into the knees and hips of 400 patients in the last two years, in connection with a company known as Regenexx that is based in Colorado. He says he thinks the treatments are allowing some patients to postpone getting hip or knee replacements.?Chris Centeno, the doctor behind Regenexx, says it?s a mistake to apply the same standards of evidence to bone marrow treatments as is asked of new drugs. ?The university approach has the obvious advantage of evidence first but the obvious problem of a glacially slow and hyper-expensive process to translate therapies to patients,? he says.

But, Fu asks, what if the injections don?t really work? They could gobble up huge amounts of money for years until doctors gradually move on to something else. He notes how many NFL players used to suck oxygen by the sidelines, until they realized it wasn?t really doing anything. Now oxygen tanks are seen less often at sports events, Fu says.?The Rice authors say what bothers them is the role that NFL players have had in promoting unproven treatments. One U.S. clinic, SmartChoice Stem Cell Institute, says it has signed former NFL linebacker Tom McManus as a spokesman. Meanwhile, clinics offering overseas procedures, like Precision Stem Cell, use images of players including Rolando McClain, now of the Dallas Cowboys, and promote media reports of players who have had treatments.

?Our patients are reading that and saying ?We want what this guy got,?? says Shane Shapiro, an assistant professor of orthopedic surgery at the Mayo Clinic in Florida.?Shapiro is now carrying out a test of the bone marrow treatment in about 25 older people with arthritic knees. The process is similar to that being offered by private clinics. After obtaining bone marrow through a biopsy, it?s spun in a centrifuge to concentrate cells. He says he ends up with about 40 million cells?a tiny fraction of which are stem cells. To create a scientifically controlled situation, each patient gets two injections: bone marrow in one knee and a placebo of salt water in the other.?It will take another year to know the results. In the meantime, Shapiro says he?s turning away athletes who want to pay for the injections. ?I have not felt comfortable charging for it without knowing if it really works,? he says.

By Antonio Regalado?- MIT Technology Review

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