Restoring walking after spinal cord injury.

One of the most obvious deficits following a spinal cord injury is the difficulty in walking, forcing many patients to use wheelchairs for locomotion. Over the past decade considerable effort has been directed at promoting the recovery of walking and to find effective treatments for spinal cord injury. Advances in our knowledge of the neuronal control of walking have led to the development of a promising rehabilitative strategy in patients with partial spinal cord injury, namely treadmill training with partial weight support. The current focus is on developing more efficient training protocols and automating the training to reduce the physical demand for the therapists. Mechanisms underlying training-induced improvements in walking have been revealed to some extent in animal studies. Another strategy for improving the walking in spinal cord injured patients is the use of functional electric stimulation of nerves and muscles to assist stepping movements. This field has advanced significantly over the past decade as a result of developments in computer technology and the miniaturization of electronics. Finally, basic research on animals with damaged spinal cords has focused on enhancing walking and other motor functions by promoting growth and regeneration of damaged axons. Numerous important findings have been reported yielding optimism that techniques for repairing the injured spinal cord will be developed in the near future. However, at present no strategy involving direct treatment of the injured spinal cord has been established for routine use in spinal cord injured patients. It now seems likely that any successful protocol in humans will require a combination of a treatment to promote re-establishing functional connections to neuronal networks in the spinal cord and specialized rehabilitation training to shape the motor patterns generated by these networks for specific behavioral tasks.