Journal: Best Practice and Research Clinical Rheumatology. 2007 Jun;21(3):465-80.
Authors and affiliation: Nielsen LA, Henriksson KG. Laboratory for Experimental Pain Research, Center for Sensory-Motor Interactions (SMI), Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
Chronic musculoskeletal pain has biological, psychological and social components. This review deals with the biological factors, with emphasis on the Fibromyalgia syndrome (FMS).
Studies on central sensitization of pain-transmitting neurons, changes in endogenous pain modulation that give rise to pain disinhibition, referred pain, pain-related decrease in muscle strength and endurance, and pain generators in deep tissues are reviewed.
In FMS there is strong scientific support for the statement that the biological part of the syndrome is a longstanding or permanent change in the function of the nociceptive nervous system that can be equated with a disease. Further research is necessary in order to determine which methods are best for diagnosis of the pain hypersensitivity in clinical practice.
FMS may be the far end of a continuum that starts with chronic localized/regional musculoskeletal pain and ends with widespread chronic disabling pain.