Lawrence Goldstein PhD
Spinal cord injury (SCI) resulting from accidents, gunshots or other traumas is a tragedy that affects hundreds of thousands of people of all ages. Vehicular accidents cause about 44% of these injuries. Nearly one-quarter are the result of violence and 22% are the result of falls. Sports injuries account for 7% of spinal cord injuries. The remaining 1% of spinal cord injuries results from work-related or other accidents.
Many SCI victims tend to be young adults and most are male. About 53% of spinal cord injuries occur among persons in the 16 to 30 year age group. Overall, 81% of all persons suffering form spinal cord injuries are male.
Spinal cord injuries involve the damage and destruction of nerve fibers within the spinal cord, a central component of the communication system our brains use to direct the functioning of our bodies. Breaks in this communication system lead to paralysis and diminished or absent control of basic body functions.
The location of damage along the spinal cord often determines the areas affected by spinal injury. For example, individuals experiencing a spinal break along the lower back may retain the use of their upper extremities. Unfortunately, fewer faculties are retained if the break site is closer to the head and neck. Patients injured very near to the top of the spinal cord will lose their ability to breathe on their own in addition to being immobilized.
Paraplegia (losses of movement and sensation in the lower body) affects 47% of the SCI population and 52% are affected by quadriplegia (losses of movement and sensation in both the arms and legs).
Human and Social Costs
Approximately 250,000 to 400,000 people in the U.S. have spinal cord injuries. Every year, approximately 11,000 more Americans sustain new spinal cord injuries – amounting to 30 new injuries every day.
Spinal cord injuries cost the nation at least $9.7 billion per year for medical care, equipment and disability support. Trauma and rehabilitation costs alone are almost $250,000 for each SCI patient. Additional lifetime costs incurred by SCI individuals average $400,000 and can reach as high as $2.1 million depending on the extent of injury.
Based on federal and state data, more than 2,000 Kansans currently suffer from spinal cord injury. It is estimated that the direct health care costs and indirect social costs (lost work time, etc.) associated with spinal cord injury will cost Kansans tens of millions of dollars in 2005 – and more than a billion dollars over the next 25 years.
As with other devastating diseases and injuries, the emotional costs to SCI sufferers and their families are extremely high and cannot be quantified in terms of dollars and cents.
The Potential for Stem Cell Cures
More than 50 years of research on adult stem cells, taken from adult tissues, has produced such lifesaving treatments as bone marrow transplants for leukemia patients. And, adult stem cells are likely to provide additional cures for some diseases and injuries in the years ahead.
However, the new frontier in stem cell research involves early, or “embryonic,” stem cells (ES cells). Unlike adult stem cells, ES cells have the potential to turn into and regenerate any type of cell or tissue in the human body. As a result, ES cells could provide cures for many currently incurable or common diseases and injuries that cannot be cured with adult stem cells, or more effective treatments than adult stem cells may provide.
There are two basic sources of ES cells for such potential therapies. One source is the leftover embryos at fertility clinics that would otherwise be discarded and destroyed. ES cells can also be produced with Somatic Cell Nuclear Transfer (SCNT), a process that uses a patient’s own cells and an unfertilized human egg to make ES cells. SCNT has the added advantage of producing ES cells that will automatically match the patient’s genetic makeup. As a result, SCNT avoids the need to find a genetically matching donor and the problem of immune system rejection, two limitations associated with donated adult and ES cells.
Various animal studies conducted in recent years indicate that ES cell transplants could be used to repair and regrow spinal cord nerve fibers – and could someday allow SCI victims to walk again. Much additional research is needed to determine if this hope can be turned into a reality. But the potential is clear.
This potential has been dramatized by several recent studies in which mice and rats with paralyzed legs have regained the ability to move their legs again after receiving transplants of ES cells.
For example, researchers at Johns Hopkins have shown that injections of ES cells into the fluid around the spinal cord of paralyzed rats clearly improved the animals’ ability to control their hind limbs. (Before and after videos from these studies are available online at http://www.isscr.org/public/movies.htm under the heading “Walking Rat.”)
It will take years of additional research to determine if any stem cell therapies can lead to similar results in humans. However, the consensus of the medical and patient community is that all types of stem cell research should be pursued in the effort to find a way to repair spinal cord injuries, and that ES cells can play an important role in this effort.
That’s why ES cell research is strongly supported by the overwhelming majority of medical researchers; medical organizations, like the American Medical Association; and disease and patient advocacy groups like the National Council on Spinal Cord Injury, Daniel Heumann Fund for Spinal Cord Research, Research for Cure of Spinal Cord Injury, United Spinal Association, Cure Paralysis Now and Paralysis Project of America.