title: The predetermined sites of examination for tender points in fibromyalgia syndrome are frequently associated with myofascial trigger points.
abstract: The aim of this present study is to test the hypotheses that the 18 predetermined sites of examination for tender points (TP sites) in fibromyalgia syndrome (FMS) are myofascial trigger points (MTrPs), and that the induced pain from active MTrPs at TP sites may mimic fibromyalgia pain. Each TP site was evaluated with manual palpation followed by intramuscular electromyographic (EMG) registration of spontaneous electrical activity to confirm or refute the existence of an MTrP in 30 FMS patients. Overall spontaneous pain intensity and pain pattern were recorded before manual identification of MTrPs. Local and referred pain pattern from active MTrPs were drawn following manual palpation at TP sites.
  
  
  RESULTS
  Showed that most of the TP sites are MTrPs. Local and referred pain from active MTrPs reproduced partly the overall spontaneous pain pattern. The total number of active MTrPs (r = .78, P < .0001), but not latent MTrPs (r = -.001, P = .99), was positively correlated with spontaneous pain intensity in FMS. The current study provides first evidence that pain from active MTrPs at TP sites mimics fibromyalgia pain. MTrPs may relate to generalized increased sensitivity in FMS due to central sensitization.
  
  
  CONCLUSIONS
  This article underlies the importance of active MTrPs in FMS patients. Most of the TP sites in FMS are MTrPs. Active MTrPs may serve as a peripheral generator of fibromyalgia pain and inactivation of active MTrPs may thus be an alternative for the treatment of FMS.
authors.affiliation: Laboratory for Musculoskeletal Pain and Motor Control, Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Aalborg University, Aalborg, Denmark. ghy@hst.aau.dk
authors.forename: Hong-You
authors.initials: HY
authors.lastname: Ge
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Bente
authors.initials: B
authors.lastname: Danneskiold-Samsøe
authors.forename: Thomas
authors.initials: T
authors.lastname: Graven-Nielsen
authors.forename: Lars
authors.initials: L
authors.lastname: Arendt-Nielsen
mesh_terms: D004576:Electromyography; D005260:Female; D005356:Fibromyalgia / Q000175:diagnosis* / Q000503:physiopathology*; D006801:Humans; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology; D009209:Myofascial Pain Syndromes / Q000175:diagnosis* / Q000503:physiopathology*; D009460:Neurologic Examination / Q000379:methods; D010147:Pain Measurement / Q000379:methods*; D017288:Pain Threshold / Q000502:physiology; D053591:Referred Pain / Q000175:diagnosis / Q000503:physiopathology; D010173:Palpation / Q000379:methods; D011237:Predictive Value of Tests; D011984:Sensory Receptor Cells / Q000502:physiology*; D012720:Severity of Illness Index