'Walk again' warning

As a researcher and a neurologist who has cared for patients with spinal cord injuries, I applaud most scientific efforts that help us better understand these injuries, but I do not expect that data from animal experiments will translate into effective treatments for humans (11 February, p 11).

Despite more than 40 years of spinal cord injury research on animals and numerous "breakthroughs" in laboratory animals, spinal cord treatments, including Naloxone, Nimodipine, interleukin-10, and even the controversial methylprednisolone, fail when applied to human patients. Precisely controlled animal experiments simply do not mimic the complexity of human spinal cord injury, which often includes organ failure, shock, multiple fractures and infections.

The numerous differences between humans and animals in spinal cord neuroanatomy, physiology and reaction to injury - even at the cellular level - can manifest as profound differences in disease physiology and treatment effectiveness. For example, many animals possess a "central pattern generator" that allows spinal cord function independent of input from higher brain centres, but this has not been shown to exist in humans.

Rather than continue with disappointing and wasteful animal experiments, scientists who want to help patients with spinal cord injuries should concentrate on clinically relevant human-based research.

Physicians Committee for Responsible Medicine

From issue 2540 of New Scientist magazine, 25 February 2006, page 25