title: Facial pain associated with fibromyalgia can be marked by abnormal neuromuscular control: a cross-sectional study.
abstract: BACKGROUND
  Temporomandibular disorder (TMD) development in fibromyalgia syndrome (FMS) is not yet fully understood, but altered neuromuscular control in FMS may play a role in triggering TMD.
  
  
  OBJECTIVE
  The purpose of this study was to verify the association between neuromuscular control and chronic facial pain in groups of patients with FMS and TMD.
  
  
  METHODS
  A cross-sectional study was conducted.
  
  
  METHODS
  This study involved an analysis of facial pain and electromyographic activity of the masticatory muscles in patients with FMS (n=27) and TMD (n=28). All participants were evaluated according to Research Diagnostic Criteria for Temporomandibular Disorders and surface electromyography (SEMG). Myoelectric signal calculations were performed using the root mean square and median frequency of signals.
  
  
  RESULTS
  The data revealed premature interruption of masticatory muscle contraction in both patient groups, but a significant correlation also was found between higher median frequency values and increased facial pain. This correlation probably was related to FMS because it was not found in patients with TMD only. Facial pain and increased SEMG activity during mandibular rest also were positively correlated.
  
  
  CONCLUSIONS
  Temporal conclusions cannot be drawn from the study. Also, the study lacked a comparison group of patients with FMS without TMD as well as a control group of individuals who were healthy.
  
  
  CONCLUSIONS
  Altered neuromuscular control in masticatory muscles may be correlated with perceived facial pain in patients with FMS.
authors.affiliation: Department of Anatomy, Piracicaba Dental School, State University of Campinas, Piracicaba, PO Box 52, Limeira Avenue, 901, São Paulo, Brazil 13414-903. maisa_gui@yahoo.com.br
authors.forename: Maísa Soares
authors.initials: MS
authors.lastname: Gui
authors.forename: Cristiane Rodrigues
authors.initials: CR
authors.lastname: Pedroni
authors.forename: Luana M Martins
authors.initials: LM
authors.lastname: Aquino
authors.forename: Marcele Jardim
authors.initials: MJ
authors.lastname: Pimentel
authors.forename: Marcelo Correa
authors.initials: MC
authors.lastname: Alves
authors.forename: Sueli
authors.initials: S
authors.lastname: Rossini
authors.forename: Rubens
authors.initials: R
authors.lastname: Reimão
authors.forename: Fausto
authors.initials: F
authors.lastname: Berzin
authors.forename: Amélia Pasqual
authors.initials: AP
authors.lastname: Marques
authors.forename: Célia Marisa
authors.initials: CM
authors.lastname: Rizzatti-Barbosa
mesh_terms: D000704:Analysis of Variance; D003430:Cross-Sectional Studies; D004576:Electromyography; D005157:Facial Pain / Q000503:physiopathology*; D005260:Female; D005356:Fibromyalgia / Q000503:physiopathology*; D006801:Humans; D008410:Masticatory Muscles / Q000503:physiopathology*; D008875:Middle Aged; D010147:Pain Measurement; D013705:Temporomandibular Joint Disorders / Q000503:physiopathology*