Limiting an injury will be easier than reversing it, and so treatments for ameliorating the secondary damage that follows acute trauma can be expected to enter human testing most quickly. Of the repair strategies, promoting remyelination will be the simplest to accomplish, because all it demands is the recoating of intact axons. Remyelination strategies have the potential to produce meaningful recovery of function, such as returning control over the bladder or bowel— abilities that uninjured people take for granted but that would mean the world to those with spinal cord injuries.
Of course, tendon-transfer surgery and advanced electrical devices can already restore important functions in some patients. Yet for many people, a return of independence in daily activities will depend on reconstruction of damaged tissue through the regrowth of injured axons and the reconnection of disrupted pathways.
So far, few interventions in animals with well-established spinal cord injuries have achieved the magnitude of regrowth and synapse formation that would be needed to provide a hand grasp or the ability to stand and walk in human adults with long-term damage. Because of the great complexities and difficulties involved in those aspects of cord repair, we cannot guess when reconstructive therapies might begin to become available. But we anticipate continued progress toward that end.
Traditionally, medical care for patients with spinal cord injury has emphasized compensatory strategies that maximize use of any residual cord function. That focus is now expanding, as treatments designed to repair the damaged cord and restore lost function—science fiction only a decade ago—are becoming increasingly plausible.