Neuroinflammation in chronic pain: Myth or reality?

The term "neuroinflammation" (NI) is currently popular, and the meaning is a long way from the original description restricted to findings after stroke, central nervous system (CNS) trauma, or CNS infection. NI has been implied in association with diseases of the CNS, such as Alzheimer's, Parkinson's, and Multiple Sclerosis. In addition, it has also been associated with psychiatric/psychological diagnoses, chronic pain diagnoses, stress, many functional disorders, and "central sensitization." Findings proposed to be evidence for NI have been found not only in the brain but also in the spinal cord, dorsal root ganglia, and peripheral nerves. Worrisome is the mistaken confusion that leads "association" to be "proof of cause," where there is much dispute over whether findings are really evidence for inflammation. This article is a short review of the literature and a critique of the concept of NI.