title: Pain sensitivity and pericranial tenderness in children with tension-type headache: a controlled study.
abstract: OBJECTIVE
  To compare tenderness and pain sensitivity in children (aged 7-17 years) with tension-type headache (TTH) and healthy controls using total tenderness score (TTS), pressure pain threshold (PPT), and pain perceived at suprapressure pain threshold (supraPPT).
  
  
  METHODS
  Twenty-three children with frequent episodic TTH, 36 with chronic TTH, and 57 healthy controls were included. TTS was measured bilaterally at seven pericranial myofascial structures. PPT and supraPPT were assessed in the finger, m. temporalis, and m. trapezius by a Somedic® algometer. SupraPPT was defined as the pain perceived at a stimulus calculated as the individual site-specific PPT + 50%.
  
  
  METHODS
  The effect of group, sex, age, headache frequency, intensity, and years on TTS, PPT, and supraPPT was analyzed by general linear models. Confirmatory factor analysis was analyzed for mutual relations between measurements.
  
  
  CONCLUSIONS
  Tenderness increased uniformly in both frequent episodic TTH (median 14; interquartile range [IQR] 10-18; P < 0.001) and chronic TTH (median 13; IQR 9-20; P < 0.001) compared to controls (median 5, IQR 3-11). However, the children with frequent episodic TTH and chronic TTH did not show significantly increased sensitivity when measured by PPT or supraPPT. Factor analysis confirmed that the site-specific measurements depended on general latent variables. Consequently, the PPT and supraPPT tests can be assumed to measure central pain-processing levels.
authors.affiliation: Department of Paediatrics, Children's Headache Clinic, Copenhagen University Hospital Herlev, Copenhagen, Denmark.
authors.forename: Ann-Britt L
authors.initials: AB
authors.lastname: Soee
authors.forename: Liselotte
authors.initials: L
authors.lastname: Skov
authors.forename: Svend
authors.initials: S
authors.lastname: Kreiner
authors.forename: Birte
authors.initials: B
authors.lastname: Tornoe
authors.forename: Lise L
authors.initials: LL
authors.lastname: Thomsen
keywords: pain measurement; pathophysiological mechanisms; pressure pain threshold; sensitization; suprathreshold stimulation; total tenderness score