Shortly after pitching his Oregon State University baseball team to the 2006 College World Series championship, Rob Summers was struck and paralyzed from the chest down by a hit-and-run driver.
But now, thanks to an experimental mix of physical therapy and electrical stimulation of the spinal cord, he can do something he never dreamed of doing again: stand and voluntarily make some leg movements.
"It was completely unexpected," says V. Reggie Edgerton, professor of integrative biology and physiology, and neurobiology at the University of California, Los Angeles. Until Summers, scientists believed that patients with a completely severed spinal cord would never be able to regain voluntary control of their paralyzed limbs.
To see if spinal cord stimulation could be successful in people, Edgerton and his collaborator, Dr. Susan Harkema at the University of Louisville, implanted an electrode array normally used to treat back pain in Summers' lower back. Harkema led the clinical study, which was supported by the National Institute of Biomedical Imaging and Bioengineering, the National Institute of Neurological Disorders and Stroke, and the Christopher and Dana Reeve Foundation.
After years of being bound to his wheelchair, Summers can now push himself up and remain standing for a few minutes while receiving stimulation. With the support of a harness and help from therapists, he also can make stepping motions on the treadmill. Other functions impaired by his injury have improved, too: body temperature regulation, bladder and bowel control, and sexual function.
Edgerton thinks connections between Summers' brain and the part of the spinal cord below the point of his injury may have been spared, or that the therapy encouraged nerve cells to make new connections.