title: Test-retest reliability of isometric and isokinetic knee extension and flexion in patients with fibromyalgia: evaluation of the smallest real difference.
abstract: OBJECTIVE
  To investigate the reliability of isokinetic peak torque and work and isometric peak torque measurements for knee flexion and extension in fibromyalgia (FM) patients by determining the smallest real difference (SRD).
  
  
  METHODS
  Test-retest reliability study.
  
  
  METHODS
  University laboratory.
  
  
  METHODS
  Women with FM (N=37) aged between 34 and 74 years.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  The participants performed isometric, concentric, and eccentric tests of the knee. Unilateral maximal peak torque and average work were measured for each direction (flexion, extension) and contraction (isometric, concentric, eccentric) type. Relative reliability, absolute reliability, and SRD were calculated. The 3 tests were repeated after an interval of 7 days.
  
  
  RESULTS
  With the exception of eccentric flexion, all peak torque measures had an intraclass correlation coefficient (ICC) of > 0.90, and all work measures had an ICC of > 0.85. The SRD ranged between 21% and 37% for all peak torque measures and between 40% and 73% for all work measures.
  
  
  CONCLUSIONS
  Isokinetic dynamometry provides reliable measurement of peak torque and work for isometric, concentric, and eccentric knee flexion and extension in patients with FM. The present study has generated novel SRD data, which will assist physicians, therapists, and clinicians in interpreting posttreatment changes in patients with FM.
authors.affiliation: Faculty of Sports Sciences, University of Extremadura, Caceres, Spain.
authors.forename: Jose C
authors.initials: JC
authors.lastname: Adsuar
authors.forename: Pedro R
authors.initials: PR
authors.lastname: Olivares
authors.forename: Borja
authors.initials: B
authors.lastname: del Pozo-Cruz
authors.forename: Jose A
authors.initials: JA
authors.lastname: Parraca
authors.forename: Narcis
authors.initials: N
authors.lastname: Gusi
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D005080:Exercise Test; D005260:Female; D005356:Fibromyalgia / Q000503:physiopathology*; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008875:Middle Aged; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D019415:Torque