The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain to the mid back . The brain and spinal cord together make up the central nervous system.
SPINAL CORD INJURY
A Spinal Cord Injury (SCI) is damage or trauma to the spinal cord that results in a loss or impaired function causing reduced mobility or feeling. Common causes of damage are trauma (car accident, gunshot, falls, sports injuries, etc.) or disease (Transverse Myelitis, Polio, Spina Bifida, , etc.).
The spinal cord does not have to be severed in order for a loss of functioning to occur. In most people with SCI, the spinal cord is intact, but the cellular damage to it results in loss of functioning. SCI is very different from back injuries such as ruptured disks, spinal stenosis or pinched nerves.
It is possible for a person to “break their back or neck” yet not sustain a spinal cord injury as long as only the bones (the vertebrae) around the spinal cord are damaged, but the spinal cord is not affected. In these cases, the person may not experience paralysis after the vertebrae are stabilized.
REGENERATION
Damaged nerves must first grow for regeneration to occur. There are proteins that function as “growth factors. These help prevent cell death. They also work like a “nerve fertilizer” to help neurons survive and nerves regenerate. Different pathways in the spinal cord may require particular combinations of growth factors for survival after injury
Block Inhibitory Process
One problem that occurs in regeneration is that certain factors prevent nerve cells in the central nervous system from growing. Spinal cord tissue contains certain chemicals that stop nerve regeneration and we have a way of blocking these proteins.
Electrical stimulation
Researchers at Purdue University’s Center for Paralysis Research and Indiana University School of Medicine are using low-level electrical stimulation on paralyzed dogs. They implant a small battery pack, known as a stimulator , near the dog’s spine.
It sends a weak electrical signal (thousandths of a volt) to the site of injury. This helps regenerate cells and guide growth in the damaged nerves. In about a third of the cases, the dogs improved significantly.
Stem Cells
Certain kinds of stem cells can produce any kind of cell in the body. This means they can make replacement cells for other body parts, including spinal cord cells.
Stem cells from both rodent and human tissues are being studied. One major question is what determines whether stem cells develop into cells that help regeneration, e.g. nerve cells, or cells that make myelin, and not into cells that prevent regeneration, e.g. scar tissue.
Conclusion
Spinal cord injury research has now come of age. Because of general progress in neuroscience, as well as specific advances in spinal cord injury research, researchers can test new ideas about how changes in molecules, cells, and their complex interactions determine the outcome of spinal cord injury. Inspired by demonstrations that spinal cord nerve cells can regrow, researchers are learning to manipulate trophic factors, intrinsic growth programs, and growth inhibitors to encourage regeneration.
Overcoming spinal cord injuries will require general progress in many fields of neuroscience. The future in spinal cord regeneration seems rather promising.