title: Cervical Muscle Strength and Muscle Coactivation During Isometric Contractions in Patients With Migraine: A Cross-Sectional Study.
abstract: OBJECTIVE
  This cross-sectional study investigated potential differences in cervical musculature in groups of migraine headaches vs. non-headache controls. Differences in cervical muscle strength and antagonist coactivation during maximal isometric voluntary contraction (MIVC) were analyzed between individuals with migraine and non-headache subjects and relationships between force with migraine and neck pain clinical aspects.
  
  
  METHODS
  A customized hand-held dynamometer was used to assess cervical flexion, extension, and bilateral lateral flexion strength in subjects with episodic migraine (n=31), chronic migraine (n = 21) and healthy controls (n = 31). Surface electromyography (EMG) from sternocleidomastoid, anterior scalene, and splenius capitis muscles were recorded during MIVC to evaluate antagonist coactivation. Comparison of main outcomes among groups was conducted with one-way analysis of covariance with the presence of neck pain as covariable. Correlations between peak force and clinical variables were demonstrated by Spearman's coefficient.
  
  
  RESULTS
  Chronic migraine subjects exhibited lower cervical extension force (mean diff. from controls: 4.4 N/kg; mean diff from episodic migraine: 3.7 N/kg; P = .006) and spent significantly more time to generate peak force during cervical flexion (mean diff. from controls: 0.5 seconds; P = .025) and left lateral-flexion (mean diff. from controls: 0.4 seconds; mean diff. from episodic migraine: 0.5 seconds; P = .007). Both migraine groups showed significantly higher antagonist muscle coactivity of the splenius capitis muscle (mean diff. from controls: 20%MIVC, P = .03) during cervical flexion relative to healthy controls. Cervical extension peak force was moderately associated with the migraine frequency (rs: -0.30, P = .034), neck pain frequency (rs: -0.26, P = .020), and neck pain intensity (rs: -0.27, P = .012).
  
  
  CONCLUSIONS
  Patients with chronic migraine exhibit altered muscle performance, took longer to reach peak of force during some cervical movements, and had higher coactivation of the splenius capitis during maximal isometric cervical flexion contraction. Finally, patients with migraine reported the presence of neck and head pain complaints during maximal isometric voluntary cervical contractions.
authors.affiliation: Department of Biomechanics, Medicine and Locomotor Apparatus Rehabilitation - Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil.
authors.forename: Lidiane Lima
authors.initials: LL
authors.lastname: Florencio
authors.affiliation: Department of Biomechanics, Medicine and Locomotor Apparatus Rehabilitation - Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil.
authors.forename: Anamaria Siriani
authors.initials: AS
authors.lastname: de Oliveira
authors.affiliation: Department of Biomechanics, Medicine and Locomotor Apparatus Rehabilitation - Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil.
authors.forename: Gabriela Ferreira
authors.initials: GF
authors.lastname: Carvalho
authors.affiliation: Department of Biomechanics, Medicine and Locomotor Apparatus Rehabilitation - Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil.
authors.forename: Gabriella de Almeida
authors.initials: Gde A
authors.lastname: Tolentino
authors.affiliation: Department of Neurosciences and Behavioral Sciences - Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil.
authors.forename: Fabiola
authors.initials: F
authors.lastname: Dach
authors.affiliation: Migraine & Headache Clinical Development, Global Branded R&D, Frazer, PA, USA.
authors.forename: Marcelo Eduardo
authors.initials: ME
authors.lastname: Bigal
authors.affiliation: Department of Physical Therapy, Occupational Therapy, Physical Medicine and Rehabilitation, Universidad Rey Juan Carlos, Alcorcón, Spain.
authors.forename: César
authors.initials: C
authors.lastname: Fernández-de-las-Peñas
authors.affiliation: Department of Biomechanics, Medicine and Locomotor Apparatus Rehabilitation - Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil.
authors.forename: Débora
authors.initials: D
authors.lastname: Bevilaqua Grossi
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D008881:Migraine Disorders / Q000175:diagnosis* / Q000503:physiopathology; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D009334:Neck Muscles / Q000502:physiology*; D010865:Pilot Projects
keywords: cervical spine; isometric contraction; migraine; surface electromyography