Jon Dorenbos was at a spring practice suffering from one of his bouts with long-snapper's elbow. The Philadelphia Eagles center, whose specialty is the long centering pass to punters and placekickers, often got severe discomfort in his left elbow from those repeated hard flicks in practice and in games.

The technical term is medial epicondylitis, and while it can afflict almost anyone's funny bone, it can be excruciating for athletes who make their living doing such irregular motions.

"We tried rehab stuff, strengthening the muscles around it," said Dorenbos. "Then I would get cortisone shots, which work for a while, but then you have to get another one when the discomfort comes back."

When it happened again this year, Eagles team physician Peter DeLuca suggested to Dorenbos that he try a procedure used in Europe that Eagles owner Jeffrey Lurie had read about and asked DeLuca to look into - platelet-rich plasma (PRP) therapy.

A medical team extracts a small amount of the patient's blood and has it spun in a centrifuge to separate out the platelets. The technicians then inject a teaspoon or more of concentrated platelets back into the sore tendon, muscle, or bone to speed the healing process.

"Platelets are like the EMTs of the body. They are the first cells that go to any injury," said DeLuca. "In those platelets are growth factors, which are the chemical compounds that enhance healing or start the cascade of healing in our bodies. It only makes sense that injecting a high concentration of them into a damaged area would help enhance its healing."

Two Pittsburgh Steelers, Hines Ward and Troy Polamalu, both had good results with the procedure. Dorenbos, 28, also consented to give PRP therapy a shot, so to speak. And, he says, "it seems to have worked for me, too. No pain at all."

PRP therapy has been around for complicated healing, as in bone grafts, at least since the 1950s, said Stanford University Medical Center physician Allan Mishra, who has been using it for a decade to repair soft tissue. Before the development of a better centrifuge to split the plasma from the red blood cells, though, it wasn't as useful for smaller, soft-tissue issues.

"It used to be that you had to take about 500 cc's of blood to process to get what you needed of PRP, so it really had to be used for a major operation," said Mishra.

Now, he said, with the smaller and more sophisticated centrifuge, doctors can take about 10 to 20 cubic centimeters, about the same amount as is drawn for common blood tests. So the whole procedure - drawing blood, centrifuging it, and injecting it into the affected area - can be done in less than an hour in a doctor's office. Mishra started using it for tendon injuries about four years ago and has been logging the results. He said that, in most cases, it has not only eased the pain of the injury, but cured it as well.

"Ninety percent of those people with tennis elbow that I have treated have been cured," said Mishra. "It makes sense that using a patient's own blood - with its healing properties - would be useful in healing soft tissue as well."

Peter Kleiner believes he is back on the golf course again, hacking away happily, because of PRP therapy. Kleiner, 48, had the obverse of tennis elbow, commonly known as golfer's elbow - tennis elbow being on the outside of the joint and golfer's elbow on the inside. He had golfed and worked out all his adult life, but about a year ago had virtually been shut down by the pain.

"I first tried resting, then stretching, then ultimately, in January, I got a cortisone shot, then another one," said Kleiner, who owns PK Media, a Mount Laurel consulting firm that arranges naming rights for municipal and parking facilities. "It was killing me in pain, and also killing me that I couldn't work out like I always had."

Then DeLuca, his orthopedist at the Rothman Institute at Thomas Jefferson University Hospital, told him about PRP therapy and invited him to participate in a research study on the treatment.

"I had been working out and playing golf since I was 18. I had had both my shoulders operated on and back surgery for a herniated disc, and I really wasn't looking forward to an operation again," he said. "It was at least worth a try. There seemed really no downside. It seemed low-risk, taking something from my body and putting it back in again.

"It was like nothing. It seemed only 10 minutes - drawing the blood, spinning it, injecting it back in, giving me some ice," said Kleiner. "I had the procedure on Monday, and I was back out on the golf course on Wednesday."

While PRP therapy seems like a miracle breakthrough, much like laser eye surgery to cure vision problems, it should be used with a little caution in tendons and the like, according to Samir Mehta, chief of the Orthopedic Trauma Service at the Hospital of the University of Pennsylvania. Mehta has been using PRP therapy in his trauma unit for about two years to help heal fractures. He said the Food and Drug Administration at this point has approved PRP therapy only for bone healing, not for soft tissue.

"That doesn't mean it won't work, just that the FDA doesn't officially approve of it and thinks there should be a longer time studying it," said Mehta. "You would be doing this 'off-label.' But I am encouraged about what I hear. Medicine is part art and creativity, and this may well fall into that category."

Mehta said he was a fan of orthobiologics, which encompasses the use of biological agents, such as platelet-rich plasma, to repair muscular-skeletal tissue. In Europe particularly, he said, more creative solutions to medical problems, like PRP therapy, get approved more quickly.

That is how DeLuca came to use PRP therapy. He said that Lurie, his boss at the Eagles, had a friend who had read about the therapy being used in Germany and went there to get it done for his degenerated back disc. DeLuca said it was only a matter of time before PRP therapy would be common for repair of Achilles' tendons, for healing of plantar fasciitis, for acute muscle strains such as hamstring injuries, and the like.

"It is relatively risk-free, so there is a good cost-benefit to it," he said. Right now, insurance generally covers the doctor's evaluation and injection, he said, but not the sophisticated syringe, which can cost up to $250. Not all health insurers will cover it, said Mehta, because it is not yet FDA approved. But even though he hasn't used it yet for soft-tissue injuries, he, too, thinks it is a low-risk therapy with a high potential benefit.

"There is a risk with everything, but here you are being injected with your own blood right after it has been taken out of you, so there is no mislabeling of a vial or something like that," he said. "There are many people who have said it worked for them, especially for ongoing pain, so aside from the lack of insurance coverage, it would seem a lot of people might inquire about it."

Certainly it has a fan in middle-aged jock Kleiner.

"When you talk about fixing something that has bothered you for years in an hour in a doctor's office, well, it was a no-brainer," he said. "So far, I am thoroughly optimistic."

Contact writer Robert Strauss

at rsstrauss@comcast.net.