title: Immediate and Short-Term Effects of Upper Thoracic Manipulation on Myoelectric Activity of Sternocleidomastoid Muscles in Young Women With Chronic Neck Pain: A Randomized Blind Clinical Trial.
abstract: OBJECTIVE
  The aim of this study was to assess the immediate and short-term effects of upper thoracic spine manipulation on pain intensity and myoelectric activity of the sternocleidomastoid muscles in young women with chronic neck pain.
  
  
  METHODS
  A randomized clinical trial was carried out involving 32 women with chronic neck pain (mean age, 24.8 ± 5.4 years) allocated to an experimental group and a placebo group. Three evaluations were carried out: baseline, immediate postintervention, and short-term postintervention (48-72 hours after intervention). Myoelectric activity of the right and left sternocleidomastoid muscles was assessed at rest and during isometric contractions for cervical flexion and elevation of the shoulder girdle. Neck pain intensity was assessed at rest using a visual analog scale. Comparisons of the data were performed using 2-way repeated-measures analysis of variance with the Bonferroni correction. The level of significance was set at P < .05.
  
  
  RESULTS
  A moderate treatment effect on myoelectric activity of the right and left sternocleidomastoid muscles during isometric elevation of the shoulder girdle was found in the experimental group only on the short-term postintervention evaluation (d > 0.40). No statistically significant differences were found for any of the variables analyzed in the intergroup comparisons at the different evaluation times (P > .05).
  
  
  CONCLUSIONS
  No statistically significant differences were found in the intragroup or intergroup analyses of the experimental and placebo groups regarding myoelectric activity of the cervical muscles or the intensity of neck pain at rest in the immediate or short-term postintervention evaluations.
authors.affiliation: Doctoral Student, Laboratory of Therapeutic Resources, Postgraduate Program in Science of Human Movement, Methodist University of Piracicaba, Piracicaba, SP, Brazil.
authors.forename: Paulo Fernandes
authors.initials: PF
authors.lastname: Pires
authors.affiliation: Master's Student, Laboratory of Therapeutic Resources, Postgraduate Program in Physical Therapy, Methodist University of Piracicaba, Piracicaba, SP, Brazil.
authors.forename: Amanda Carine
authors.initials: AC
authors.lastname: Packer
authors.affiliation: Doctoral Student, Laboratory of Physiotherapeutic Resources, Postgraduate Program in Rehabilitation and Functional Performance, University of São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Almir Vieira
authors.initials: AV
authors.lastname: Dibai-Filho
authors.affiliation: Professor, Laboratory of Therapeutic Resources, Postgraduate Program in Science of Human Movement, Methodist University of Piracicaba, Piracicaba, SP, Brazil. Electronic address: drodrigues@unimep.br.
authors.forename: Delaine
authors.initials: D
authors.lastname: Rodrigues-Bigaton
mesh_terms: D000328:Adult; D059350:Chronic Pain / Q000503:physiopathology* / Q000628:therapy*; D004576:Electromyography; D005260:Female; D006801:Humans; D020393:Manipulation, Spinal; D009334:Neck Muscles / Q000503:physiopathology*; D019547:Neck Pain / Q000503:physiopathology* / Q000628:therapy*; D059408:Pain Management / Q000379:methods*; D016037:Single-Blind Method; D013997:Time Factors; D055815:Young Adult
keywords: Electromyography; Musculoskeletal Manipulations; Neck Pain