Spine Stimulator Lets the Paralyzed Stand Again
From: Discover Magazine - Jan/Feb 2013 - page 36
By Nate Berg

Last year two paralyzed people briefly stood again, aided by a device that
electrically stimulates the lower spinal cord. They were among the first
beneficiaries of a hugely promising technique that researchers hope could one
day enable many paralyzed people to walk again. 

The spinal cord carries the brain signals that control movement of the limbs.
If the cord gets clipped by disease or Injury, the communication lines go
dead; because nerve fibers have limited ability to regrow, the resulting
paralysis can be permanent. But starting in the 1990s, UCLA neuroscientist
Reggie Edgerton showed that when stimulated with small electrical pulses, the
spinal cord can wake up those nerve fibers and coordinate standing and
walking - without any input from the brain. Edgerton implanted electrodes in
paralyzed rats, then stimulated their spinal cords while researchers moved
the animals' legs in a stepping motion on a treadmill. After four to eight
weeks of training, the rats were able to walk on their own. 

Now there is compelling evidence that what worked for rats will work for
humans, too. In 2008 Edgerton's team implanted electrodes in the spinal cord
of paralyzed former college baseball player Rob Summers. After three days of
treadmill therapy, Summers was able to stand on his own. Unexpectedly, he
also experienced gradual improvements in blood pressure regulation, bladder
control, and sexual function. Last year two other patients experienced
similar success - an important advance, because unlike Summers, neither was
in exceptional physical condition prior to injury, and one of them had
absolutely no feeling below the chest. 

The next step is to go from standing to walking. Edgerton's most successful
rat experiments required administering drugs that help muscles contract. He
hopes to conduct analogous human tests within a few years. 

Links:
Reggie Edgerton
https://www.ibp.ucla.edu/physcifacultyindiv.php?FacultyKey=82

Rob Summers willing to walk again (with video 3:15)
http://espn.go.com/espn/otl/story/_/id/7373090/rob-summers-former-oregon-state-beavers-pitcher-paralyzed-accident-never-imagined-impact-world-baseball