Because of that quality, the cells (since named “stem”) have the uncanny ability to transform themselves—depending on their surroundings in the body--into any of more than 200 different cell types as required. Since then, researchers have discovered how to extract and grow human stem cells.
The breakthrough was a surgeon's dream: a material that could theoretically mend damaged bones, tendons, and organs with an efficiency never before imagined. At the time, there were just two sources of human stem cells: cadavers and embryos. And it's the latter variety that set off a firestorm of political and religious debate that shows no signs of subsiding.
Underneath the rhetorical fireworks, though, surgical patients are already receiving the benefits of stem cells every day. One national company at the forefront of stem cell supply, Nutech Medical, has its headquarters in Birmingham. And some Alabama physicians are the first in the nation to test the effectiveness of a different stem cell therapy, designed by the tissue bank AlloSource, specifically for spinal fusion.
“Our company has been in business since 1994,” says Howard Walthall, President of Nutech Spine. “We obtain our tissue from a fairly small geographic region, but it's distributed to physicians throughout the country, including Alaska.”
One of the company's products called NuCel, used primarily in orthopedic and neurosurgery, is described by Nutech as “a unique in-vivo liquid wound covering, providing a defensive barrier at the surgical site in situations where a patch covering is either inadequate or inconvenient.”
Mark Prevost, MD of Southern Orthopedics and Sports Medicine in Jasper, is among orthopedic surgeons who routinely use stem cell products in their spine procedures. “The tissue I use comes from placentas, and has a high potential for becoming bone-producing cells,” he says. “But interestingly, some of the latest research suggests that all the cells might not actually have to become bone to work, because the proteins they signal seem to stimulate the body to do more bone-building on its own.
“Of course there are always more studies to be done, but we clearly have much better fusion rates when we use the product than we did before it was available.”
In the years prior to the new technological breakthroughs, the gold standard for obtaining such repair tissue was a so-called autogenous graft, according to surgeon Larry Parker, MD of The Orthopedic Center in Huntsville. The bone cells were harvested from the patient's own body, typically a location such as the iliac crest.
“The main problem,” Parker says, “is that such a graft creates a second surgical site, which can be painful afterward, even long-term. Another problem is inconsistency of the tissue itself. With an older patient, particularly one who's suffering from osteoporosis, the quality of the graft material may be very poor. The big goal of the surgery is to achieve fusion, and if those bones haven't fused in three to six months, you're essentially back to the same problem you started with.”
Parker is among a group of Alabama physicians helping to test the effectiveness of a new product called AlloStem, made by the non-profit tissue bank AlloSource. AlloStem is made from donated cadaveric fat tissue, into which stem cells are infused to make their limited quantities go as far as possible. The resulting cubes or strips of material are inserted during surgery to help grow bone at the fusion sites.
“The new products of the past decade have been a real advance, as an alternative to autogenous grafts,” Parker says.
The advances are particularly significant, according to Parker, because the number of spinal surgeries has steadily increased over the past decade. A recent survey in the journal Spine says that neck and back pain are the major cause of sick leave among workers, and that some 80 percent of men are afflicted by the conditions at some point.
“I think the main reason for the increase is that the population is aging,” Parker says. “And as a result, the cascade of degenerative events that lead to spine problems are more prevalent. But between the improvements in implant technologies and in the hardware available, we can now do procedures so judiciously that older patients are generally able to be back to their regular daily activities much sooner.”
The good news, says Prevost, is that such breakthroughs are probably not over. “Judging by the ongoing research, I believe that the ultimate answer is not going to be just one perfect therapy,” he says. “There's such a complex series of events in the body to make fusion happen, I think we'll eventually end up with a combination of approaches. Most likely, including some we haven't even thought of yet.
“It's an exciting time to be in spinal medicine, and I'm confident that there are more good things in the future.”
