title: Measuring Eccentric Strength of the Shoulder External Rotators Using a Handheld Dynamometer: Reliability and Validity.
abstract: BACKGROUND
  Shoulder strength assessment plays an important role in the clinical examination of the shoulder region. Eccentric strength measurements are of special importance in guiding the clinician in injury prevention or return-to-play decisions after injury.
  
  
  OBJECTIVE
  To examine the absolute and relative reliability and validity of a standardized eccentric strength-measurement protocol for the glenohumeral external rotators.
  
  
  METHODS
  Descriptive laboratory study.
  
  
  METHODS
  Testing environment at the Department of Rehabilitation Sciences and Physiotherapy of Ghent University, Belgium.
  
  
  METHODS
  Twenty-five healthy participants (9 men and 16 women) without any history of shoulder pain were tested by 2 independent assessors using a handheld dynamometer (HHD) and underwent an isokinetic testing procedure.
  
  
  METHODS
  The clinical protocol used an HHD, a DynaPort accelerometer to measure acceleration and angular velocity of testing 30°/s over 90° of range of motion, and a Biodex dynamometer to measure isokinetic activity.
  
  
  METHODS
  Three eccentric strength measurements: (1) tester 1 with the HHD, (2) tester 2 with the HHD, and (3) Biodex isokinetic strength measurement.
  
  
  RESULTS
  The intratester reliability was excellent (0.879 and 0.858), whereas the intertester reliability was good, with an intraclass correlation coefficient between testers of 0.714. Pearson product moment correlation coefficients of 0.78 and 0.70 were noted between the HHD and the isokinetic data, showing good validity of this new procedure.
  
  
  CONCLUSIONS
  Standardized eccentric rotator cuff strength can be tested and measured in the clinical setting with good-to-excellent reliability and validity using an HHD.
authors.affiliation: Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University Hospital, Belgium;|Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden;|Scandinavian College of Naprapathic Manual Medicine, Stockholm, Sweden.
authors.forename: Fredrik R
authors.initials: FR
authors.lastname: Johansson
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden;|Scandinavian College of Naprapathic Manual Medicine, Stockholm, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: Skillgate
authors.affiliation: Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University Hospital, Belgium;
authors.forename: Mattis L
authors.initials: ML
authors.lastname: Lapauw
authors.affiliation: Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University Hospital, Belgium;
authors.forename: Dorien
authors.initials: D
authors.lastname: Clijmans
authors.affiliation: Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University Hospital, Belgium;
authors.forename: Valentijn P
authors.initials: VP
authors.lastname: Deneulin
authors.forename: Tanneke
authors.initials: T
authors.lastname: Palmans
authors.affiliation: Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University Hospital, Belgium;
authors.forename: Human Kinetic
authors.initials: HK
authors.lastname: Engineer
authors.affiliation: Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, Ghent University Hospital, Belgium;
authors.forename: Ann M
authors.initials: AM
authors.lastname: Cools
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D015444:Exercise / Q000502:physiology; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D015588:Observer Variation; D011897:Random Allocation; D016059:Range of Motion, Articular / Q000502:physiology; D015203:Reproducibility of Results; D012399:Rotation; D017006:Rotator Cuff / Q000502:physiology; D012782:Shoulder / Q000502:physiology*; D055815:Young Adult
keywords: eccentric testing; injury prevention; rehabilitation; upper extremity