In the world of professional sports, teams invest tens of millions of dollars in players. Those players are under intense pressure to show a return on that investment for the team, and that means playing as hard as possible for as long as possible. So it’s no surprise that players facing serious injuries will often turn to any treatment that might get them back in the game.

image courtesy Scientific American

A new study published last week in 2014 World Stem Cell Report (we blogged about it here) highlighted how far some players will go to keep playing, saying at least 12 NFL players have undergone unproven stem cell treatments in the last five years. A session at the recent World Stem Cell Summit in San Antonio, Texas showed that football is not unique, that this is a trend in all professional sports.

Dr. Shane Shapiro, an orthopedic surgeon at the Mayo Clinic, says it was an article in the New York Times in 2009 about two of the NFL players named in the World Stem Cell Report that led him to becoming interested in stem cells. The article focused on two members of the Pittsburgh Steelers team who were able to overcome injuries and play in the Super Bowl after undergoing stem cell treatment, although there was no direct evidence the stem cells caused the improvement.

“The next day, the day after the article appeared, I had multiple patients in my office with copies of the New York Times asking if I could perform the same procedure on them.”

Dr. Shapiro had experienced what has since become one of the driving factors behind many people seeking stem cell therapies, even ones that are unproven; the media reports high profile athletes getting a treatment that seems to work leading many non-athletes to want the same.

“This is not just about high profile athletes it’s also about older patients, weekend warriors and all those with degenerative joint disease, which affects around 50 million Americans. Currently for a lot of these degenerative conditions we don’t have many good non- surgical options, basically physical therapy, gentle pain relievers or steroid injections. That’s it. We have to get somewhere where we have options to slow down this trend, to slow down the progression of these injuries and problems.”

Shapiro says one of the most popular stem cell-based approaches in sports medicine today is the use of plasma rich platelets or PRP. The idea behind it makes sense, at least in theory. Blood contains platelets that contain growth factors that have been shown to help tissue heal. So injecting a patient’s platelets into the injury site might speed recovery and, because it’s the patient’s own platelets, the treatment probably won’t cause any immune response or prove to be harmful.

That’s the theory. The problem is few well-designed clinical trials have been done to see if that’s actually the case. Shapiro talked about one relatively small, non-randomized study that used PRP and in a 14-month follow-up found that 83% of patients reported feeling satisfied with their pain relief. However, 84% of this group did not have any visible improved appearance on ultrasound.

He is now in the process of carrying out a clinical trial, approved by the Food and Drug Administration (FDA), using bone marrow aspirate concentrate (BMAC) cells harvested from the patient’s own bone marrow. Because those cells secrete growth factors such as cytokines and chemokines they hope they may have anti-inflammatory and regenerative properties. The cells will be injected into 25 patients, all of whom have arthritic knees. They hope to have results next year.

Dr. Paul Saenz is a sports medicine specialist and the team physician for the San Antonio Spurs, the current National Basketball Association champions. He says that sports teams are frequently criticized for allowing players to undergo unproven stem cell treatments but he says it’s unrealistic to expect teams to do clinical studies to see if these therapies work, that’s not their area of expertise. But he also says team physicians are very careful in what they are willing to try.

“As fervent as we are to help bring an athlete back to form, we are equally fervent in our desire not to harm a $10 million athlete. Sports physicians are very conservative and for them stem cells are never the first thing they try, they are options when other approaches have failed.”

Saenz said while there are not enough double blind, randomized controlled clinical trials he has seen many individual cases, anecdotal evidence, where the use of stem cells has made a big difference. He talked about one basketball player, a 13-year NBA veteran, who was experiencing pain and mobility problems with his knee. He put the player on a biologic regimen and performed a PRP procedure on the knee.

“What we saw over the next few years was decreased pain, and a dramatic decrease in his reliance on non-steroidal anti inflammatory drugs. We saw improved MRI findings, improved athletic performance with more time on court, more baskets and more rebounds.”

But Saenz acknowledges that for the field to advance anecdotal stories like this are not enough, well-designed clinical trials are needed. He says right now there is too much guesswork in treatments, that there is not even any agreement on best practices or standardized treatment protocols.

Dr. Shapiro says for too long the use of stem cells in sports medicine has been the realm of individual physicians or medical groups. That has to change:

“If we are ever to move forward on this it has to be opened up to the scientific community, we have to do the work, do the studies, complete the analysis, open it up to our peers, report it in a reputable journal. If we want to treat the 50 million Americans who need this kind of therapy we need to go through the FDA approval process. We can’t just continue to treat the one patient a month who can afford to pay for all this themselves. “