New trial uses adult stem cells to enhance spine surgery

Sep 7 2011
Clinical trials are underway to assess the performance of adult stem cells in improving the outcome of a spine surgery used to relieve neck pain from pinched nerves.

The spinal column is protected by discs that act as cushions between the vertebra. Conditions such as degenerative disc disease erode this cushioning over time. If a disc bulges or herniates, it can put pressure on the spinal cord and lead to, among other symptoms, chronic neck pain or back pain.

Complications of herniated discs can be corrected by surgically removing them in a procedure known as a discectomy. Following an incision at the target area, the surgeon moves aside the surrounding muscles and nerve roots, removes the abnormal discs, replaces the muscles and closes the incision, according to the National Institutes of Health (NIH). A discectomy is sometimes followed by spinal fusion to meld together the vertebra that have lost their protective cushion in order to stabilize them. This procedure is often performed using bone grafts from the hip of the patient or a donor cadaver, aided by the addition of proteins and held in place by rods and screws.

However, spinal fusion efforts fail in up to 35 percent of patients, 60 percent of whom will continue to experience pain, according to researchers at the University of California in Davis, who say that adult stem cells harvested from the bone marrow may be the key to improving spinal fusion.

About 230,000 patients in the U.S. need spinal fusion, a number that is expected to grow by up to 3 percent annually as the populations grows older, the researchers said. In an effort to improve spinal fusion, UC Davis is part of a multicenter clinical trial to use adult stem cells to promote the procedure.

Though bone marrow stem cells are commonly associated with the treatment of blood disorders such as leukemia, a special type of these cells can also be manipulated in the laboratory to form bone. To test their application in spinal fusion, scientists harvested bone marrow stem cells from a donor and cultured them in high concentration, with little chance of rejection, the researchers said. Their first test subject is a 53-year-old man who underwent anterior cervical discectomy for neck pain.

The multicenter study will enroll up to 24 subjects from 10 institutions around the country. Researchers will follow the patients for 36 months after surgery. If successful, they hope the potential new treatment will not only improve the success of spinal fusion, but lead to more effective non-surgical treatments for back pain.