title: Pain-induced changes in the activity of the cervical extensor muscles evaluated by muscle functional magnetic resonance imaging.
abstract: OBJECTIVE
  To investigate the effect of experimental neck muscle pain on the activation of the cervical extensor muscles during the performance of a cervical extension exercise by the use of muscle functional magnetic resonance imaging.
  
  
  METHODS
  The activity of the multifidus, semispinalis cervicis, semispinalis capitis, and splenius capitis muscles was investigated bilaterally at 2 cervical levels (C2 to C3 and C7 to T1) in 15 healthy individuals. Measurements were taken at rest and after the performance of a cervical extension exercise without and with induced pain of the right upper trapezius (intramuscular injection of hypertonic saline).
  
  
  RESULTS
  In the pain condition, the activity of the multifidus/semispinalis cervicis was reduced bilaterally at the C7 to T1 level (P=0.045). For the semispinalis capitis, there were no significant differences between both conditions. The splenius capitis showed a significantly higher T2 shift at the left side at the C2 to C3 level (P=0.008) and a lower T2 shift at the right side at the C7 to T1 level (P=0.023).
  
  
  CONCLUSIONS
  This is the first study that has shown pain to immediately affect the activity of both deep and superficial cervical extensor muscle layers during a cervical extension exercise. The findings support recommendations for evaluation of cervical extensor muscle function early in the management of painful cervical spine injuries.
authors.affiliation: Department of Rehabilitation Sciences and Physiotherapy, Ghent University, De Pintelaan 185, Ghent, Belgium. barbara.cagnie@ugent.be
authors.forename: Barbara
authors.initials: B
authors.lastname: Cagnie
authors.forename: Shaun
authors.initials: S
authors.lastname: O'Leary
authors.forename: James
authors.initials: J
authors.lastname: Elliott
authors.forename: Ian
authors.initials: I
authors.lastname: Peeters
authors.forename: Thierry
authors.initials: T
authors.lastname: Parlevliet
authors.forename: Lieven
authors.initials: L
authors.lastname: Danneels
mesh_terms: D000200:Action Potentials; D000328:Adult; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009119:Muscle Contraction; D009334:Neck Muscles / Q000503:physiopathology*; D019547:Neck Pain / Q000503:physiopathology*; D010146:Pain / Q000503:physiopathology*; D005082:Physical Exertion