Dr. Michael Murphy is a lead investigator in a study that could reduce the number of amputations in this country. To do that, he’s using patients’ bone marrow.
“We separate out those cells and they are in a syringe,” says Murphy. “We inject it right into the muscle of the leg about one and a half to two inches deep with a 23 gauge needle at about 35 to 40 sites. We inject those cells into the leg beginning at the level knee down to the foot itself.”
This approach has been studied for close to 12 years and is now in phase three of a clinical investigation. It’s called the mobile study, and 23 medical centers around the country are involved. Murphy and his colleagues are getting results.
“We found overall there was an improvement in preventing amputations in our patient populations. More interesting, when we looked at certain subgroups of our study population, that is those patients who did not have tissue loss and non-diabetics, we found there was a significant improvement in preventing amputation.”
People with diabetes can lose vital circulation in their legs and feet because of peripheral artery disease. When that happens, ulcers can develop and tissue can die. The bone marrow Murphy is using contains stem cells. Those stem cells signal muscles to grow new blood vessels.
“They secrete various growth factors or signals that tell the skeletal muscle itself, the patient’s own tissue, to grow new blood vessels,” says Murphy. “The cells produce signals that tell the host tissue how to respond and repair itself.”
Although much of phase three is complete, the continued access program is in place to treat another 200 patients nationwide--all who could be at risk of losing a limb.