title: Efficacy of a C1-C2 self-sustained natural apophyseal glide (SNAG) in the management of cervicogenic headache.
abstract: METHODS
  Randomized, double-blind, placebo controlled trial.
  
  
  OBJECTIVE
  To determine the effect of a C1-C2 self-sustained natural apophyseal glide (SNAG) on cervicogenic headache.
  
  
  BACKGROUND
  Cervicogenic headache is a common condition causing significant disability. Recent studies have shown a high incidence of C1-C2 dysfunction, evaluated by the flexion-rotation test (FRT), in subjects with cervicogenic headache. To manage this dysfunction, Mulligan has described a C1-C2 self-SNAG, though no studies have investigated the efficacy of this intervention approach.
  
  
  METHODS
  A sample of 32 subjects (mean _ SD age, 36 +/- 3 years) with cervicogenic headache and FRT limitation were randomized into a C1-C2 self-SNAG or placebo group. After an initial instruction and practice visit in the clinic, interventions consisted of exercises applied independently by the subject twice daily at home on a continual basis. FRT range was measured twice, before and immediately after the instruction and practice visit. Headache symptoms were determined by a headache index over time, assessed by questionnaire preintervention, at 4 weeks postintervention, and at 12 months postintervention.
  
  
  RESULTS
  No differences were found in baseline measures between groups. Immediately after the initial instruction and practice visit performed with the supervision of the therapist, FRT range increased by 15 degrees (SD, 9) for the C1-C2 self-SNAG group (P < .001), which was significantly more than 5 degrees (SD, 5) for the placebo intervention (P < .001). There was also a significant interaction for the variable headache index between group and time (P < .001), indicating that group difference was dependent on time. There was no difference in headache index scores at baseline between groups. Headache index scores were substantially less in the C1-C2 self-SNAG group (mean +/- SD points at 4 weeks, 31 +/- 9; mean +/- SD points at 12 months, 24 +/- 9) compared to the placebo group (mean +/- SD points at 4 weeks, 51 +/- 15; mean +/- SD points at 12 months, 44 +/- 13) at 4 weeks (P < .001) and 12 months (P < .001), with an overall (+/-SD) reduction of 54% (+/-17%) for the individuals in the C1-C2 self-SNAG group.
  
  
  CONCLUSIONS
  These results provide evidence for the efficacy of the C1-C2 self-SNAG technique in the management of individuals with cervicogenic headache.
authors.affiliation: School of Physiotherapy, Curtin University, Perth, Western Australia. halltm@netspace.net.au
authors.forename: Toby
authors.initials: T
authors.lastname: Hall
authors.forename: Ho Tak
authors.initials: HT
authors.lastname: Chan
authors.forename: Lene
authors.initials: L
authors.lastname: Christensen
authors.forename: Britta
authors.initials: B
authors.lastname: Odenthal
authors.forename: Cherie
authors.initials: C
authors.lastname: Wells
authors.forename: Kim
authors.initials: K
authors.lastname: Robinson
mesh_terms: D000328:Adult; D001268:Atlanto-Axial Joint / Q000293:injuries* / Q000503:physiopathology; D001696:Biomechanical Phenomena; D002574:Cervical Vertebrae / Q000293:injuries* / Q000503:physiopathology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D020393:Manipulation, Spinal / Q000379:methods*; D008875:Middle Aged; D019547:Neck Pain / Q000209:etiology / Q000534:rehabilitation; D010147:Pain Measurement; D010919:Placebos; D051298:Post-Traumatic Headache / Q000503:physiopathology / Q000534:rehabilitation*; D016059:Range of Motion, Articular / Q000502:physiology*; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
chemical_list: D010919:Placebos