Healing is slow in part because tendons, ligaments and cartilage lack the interlaced blood vessels that other organs rely on for quick delivery of cells involved in repair and growth factors that encourage cells to thrive and divide. Under these circumstances, the rationale for stem cell therapy seems straightforward: bathe the injury in a healing, concentrated wave of tissue-mending cells, and the body will repair itself that much more quickly.
As so often happens in biology, however, applying a simple idea can quickly become more complicated once you start dealing with the details. For starters, the term “stem cell” describes several different types of cells with different capabilities. Embryonic stem cells, for example, can readily give rise to any type of cell found in the body under the right set of circumstances—and when plied with the right set of biochemical signals. In contrast, a more specialized group of stem cells found in the bone marrow generally begets blood cells and immune cells exclusively. These so-called hematopoietic stem cells (from Greek meaning “to make blood”) have been reliably used over the past 40 years to seed bone marrow transplants in the treatment of some cancers and immune disorders.
By the 1970s researchers had recognized another type of progenitor cell in the adult bone marrow, which they named the mesenchymal stem cell. In a laboratory dish—and, presumably, also inside the body—these cells readily multiply and give rise to various structural cells, such as fat, muscle, bone, tendon, ligament and cartilage. Studies in animals suggest that mesenchymal stem cells play important roles in the body's ability to heal after an injury, although researchers are still working out the signals and steps required to steer their differentiation into one type of tissue or another.
It turns out, for example, that mesenchymal stem cells do not regenerate tissue in isolation. They depend on other cells and growth factors that may or may not be present in a particular region of inflamed tissue, says Rocky Tuan, who directs the Center for Cellular and Molecular Engineering at the University of Pittsburgh School of Medicine. “You can inject all the best cells,” Tuan says, “but if you don't have the right combination of healing goodies around them, it's useless.”
Lab studies are also finding that mesenchymal stem cells extracted from different parts of the body can have different attributes. Those found in fat, for example, though relatively plentiful and easy to extract, do not seem to form cartilage as readily as those that come from bone marrow, Tuan says. Other studies suggest that mesenchymal stem cells also modulate the immune system and may have some part in the spread of tumors. Gathering much more basic information about how these cells behave is a vital first step before any safe and broadly reliable treatment can be developed for people, Tuan and other leading stem cell scientists argue.
Galloping Ahead of the Science
Undeterred, advocates for the immediate use of stem cell therapy in human athletes point to successes with racehorses as the best evidence that the treatment works. Yet some experts say that the same hype that makes human testimonials unreliable has enveloped company-sponsored studies of competitive horses, too.
In the July 2012 issue of Equine Disease Quarterly, Wesley Sutter of Lexington Equine Surgery and Sports Medicine in Kentucky cautioned: “To date, no published controlled clinical studies show efficacy in use of stem cell treatment for any of the conditions being treated.”
Carol Gillis, a longtime veterinarian and researcher who specializes in soft-tissue injuries in racehorses, says that the more than 22,000 ultrasound images she has captured in her studies and clinical practice have convinced her that with a tightly regimented exercise program, tendons and ligaments will heal, producing strong, well-organized fibers—all without the use of stem cells. The reason that many soft-tissue injuries end a horse's racing career, Gillis explains, is because most owners allow the animal to run free too soon, when the pain from the initial injury has faded but the tissue is still fragile.
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5 Comments
Add CommentSo what. If an athlete is going to cheat and enhance his body with a variety of drugs or other methods involving chemistry, he deserves to suffer any consequences that result from it. If he doesnt want his body screwed up by steroids or drugs, then dont do it. There is no reason to have any sort of sympathy for these people if they do this to themselves. It doesnt matter what the coach is saying or whomever, it is not hard to figure out that sports success comes from training and if you go beyond that, it is going to cause problems.
Reply | Report Abuse | Link to thisYeah... that's a dangerous game. You know what's more dangerous? CHESS!!! You don't get axed after injecting yourself with stem cells, do you? Chess, however, is a whole different story - http://sports-facts.top5.com/chess-kills!-unbelievable-causes-of-death-while-playing-chess/
Reply | Report Abuse | Link to thisThis article is irresponsibilty one-sided, parading a deceptive caution without stating the strong case for continuing use of stem cell therapies in cases where other techniques fail - short of surgery. It might be helpful, for example, to note that Dr. Tuan, quoted in the article is co-editor with Dr. O'Brien of an important new journal. Dr. O'Brien states that,
Reply | Report Abuse | Link to this"Stem cells have enormous potential for alleviating suffering for many diseases which currently have no effective therapy. The field has progressed to the clinic and it is important that this pathway is underpinned by excellent science and rigorous standards of clinical research. The journal provides an important avenue of publication in translational aspects of stem cell therapy spanning preclinical studies, clinical research and commercialization."
Prof. Timothy O'Brien,
Editor-in-Chief
Stem Cell Research & Therapy
Ms. Franklin also might be more helpful if she took the time to inquire into the "potential problems" of the standard therapies, to wit:
Surgical Complications
Knee replacement surgery is a major surgery and therefore has potential complications. The most common serious complications from this surgery are infection, wound healing problems, deep-vein thrombosis (DVT) and pulmonary embolism. Serious infections of the newly replaced joint can require additional surgery and even removal of the replacement joint. Even once these infections heal, they may result in damage to the new joint that leads to ongoing problems with pain and loosening of the joint. A study by Frosch showed that 23.6% knee replacement surgeries had some complication and that a revision operation was required in 5.6% of the cases. The most common complication in this study was delayed wound healing.
Long Term Satisfaction
Success rates of knee replacement surgery are usually measured by how many patients have revisions of the initial surgery. But many patients who have had joint replacement end up with joints that still cause them pain and problems, but live with the symptoms instead of having a revision surgery performed.
Studies that have looked at patients' expectations for knee replacement surgery have found that patients expect to be pain free and have great mobility of their knee joint after surgery. They expect to be able to return to all their old activities at the level of participation they had before they began having knee problems.
The reality is different than patient expect. A study by Mannion showed that 85% of patients expected to be pain-free after surgery, but only 43% were. 52% of patients expected to by unlimited in their usual activities, but only 20% actually were. When this group of patients was asked if they could go back in time and make the decision over again to do the surgery would they do it? - 73.9% said yes definitely, 18.9% said yes probably, 6.3% said no probably not, and 0.9% said no definitely not.
Another study by Nilsdotter found that 98% of patients expected much less or less pain postoperatively. At 1 year, 93% were experiencing much less or less pain, but by 5 years only 63% were experiencing much less or less pain than before surgery. In this same group, 96% expected their daily activity function to be better and 72% expected their sports and recreation function to be better. Daily activity levels were better for 90% at one year and 61% at 5 years, while sports and recreation function was better for only 25% at 1 year and 32% at 5 years.
Age also plays a role in functional results. A study by Elson and Brenkel showed that patients younger than 60 years old at the time of surgery were more than twice as likely to report poor pain scores at 5 years after the surgery as patient who were over 60 years old. A study by Singh found that patients younger than 60 years old were more likely to have moderate to severe pain 2 years after surgery than patients who were 61 to 70 years old.
A study by Price in patients under 60 years old found the 12 year survival rate was 82% when you considered revision surgery a failure. But when you looked at functional outcome or pain as the endpoint, the survival rate at 12 years was only 59%.
Obesity and Knee Replacement
Obesity is a rising problem in the United States and the world. Patients who are obese put more stress on their knees and are more likely to have knee problems. Obesity creates several problems for patients who have knee replacement surgery. A study by Samson showed that obese patients have a higher rate of knee replacement surgical complications than non-obese patients. They found a 3 to 9 times higher rate of infection in the obese patients. Additionally, they found that although obese patients might expect that their mobility would increase after surgery and that therefore they might lose weight, in fact, these patients did not tend to lose weight after surgery thereby continuing to put additional stress on their new joint.
Obese patients wear out their replacement joints more quickly and are more likely to need revision surgery. A study by Amin showed that obese patients had a higher risk of complications than non-obese patients (32% of patients compared to 0%) and a higher failure rate at 3 years (27.7% of patients compared to 2.4%). Another study by Vazquez-Vela Johnson looked at patients 10 years after surgery. The overall survival rate was 96.8% at 14 years. However, the worst performing groups was a group of obese men less than 60 years old who had a 10-year survival rate of only 35.7%.
Untested??? The article is completely wrong with its facts. First of all, there have been US clinics that have published their findings with stem cell treatments since 2008, especially the treatments mentioned in this article. It is a legit medical procedure that helps repair many injured athletes. The author's due diligence on finding all the facts before writing this article is the only untested thing here.
Reply | Report Abuse | Link to thisDue diligence....it should be a crime when someone in authority or looked at with any level of experience writes an "article" claiming knowledge or authority and yet IGNORES the act of due diligence....use it next time and wipe the egg off your face now, author of this misleading article. Go to pubmed.gov type in adipose derived adult stem cells and see the THOUSANDS of studies being performed as we speak....oh yeah, remember this doc, as you probably think that our country is the first and best with tech & medicine...we are 27th in the world...so maybe get your info from the ones that are actually DOING, instead of parroting the words that others say from the articles you lift your words from...this article is likened to a game of "telephone"....the real message has become distorted.
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