Scientists say they've now helped rats with spinal cord injuries overcome paralysis to walk and climb stairs.
The techniques involve a combination of chemical injections and electrical currents along with placing the rats on a treadmill.
The treatment produced an extensive rewiring in the brain and spinal cord, and the lead researcher said that more than 100 rats have regained walking ability to varying degrees. The new experiment was reported in Friday's issue of the journal Science.
The research is expected to pave the way for treatments to help human patients. Human trials could begin within the next two years.
The Associated Press contributed to this report.