Scientists may have found a source of relief for patients with chronic lower back pain in bacteria that cause food poisoning. The promising findings were published in today's issue of Neurology.
The researchers worked with a group of 31 patients suffering from lower back pain. They injected 15 with the drug Botulinum toxin A, derived from the bacterium. The others received saline solution. When surveyed three weeks later, 73 percent of the patients who had received the drug said they experienced less pain, whereas only 25 percent of the control group did. Eight weeks after the injection, 67 percent and 19 percent respectively still reported less pain. A follow-up survey of six of the patients who had taken the drug revealed that the good effects wore off after three or four months, and there were no negative side effects.
The researchers are unsure of how exactly botulinum toxin manages to relieve the pain but think that it may act on pain receptors, reducing the input from sensory fibers. The drug also alleviates muscle spasms. It remains unclear whether repeated injections will be effective. "That has been the case for patients who receive botulinum toxin injections for other disorders such as the muscle disorders dystonia and spasticity," says Bahman Jabbari of Water Reed Army Medical Center, one of the study's authors, "so hopefully that will be true for people with lower back pain as well." But, he concedes, "more studies need to be done because we looked at only a small number of patients, but these results are promising for people with this problem."