From MSNBC:
Some types of ongoing, inexplicable pain like arthritis are caused by intact, healthy nerve fibers rather than those that have been damaged, a new study finds. The discovery surprised researchers. It had not been made before partly because studies of chronic pain have tended to focus on the damaged nerves. The new understanding, reported in the Jan. 25 issue of the journal Neuroscience, could help scientists develop new types of painkillers.
The evidence so far applies only to ongoing pain associated with nerve injury and inflammation, although it may turn out to be more widely applicable, said Sally Lawson, a professor of physiology at the University of Bristol in Britain.
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