title: Comparison of dynamic sonography to stress radiography for assessing glenohumeral laxity in asymptomatic shoulders.
abstract: BACKGROUND
  Stress radiography has been the established imaging method for quantifying glenohumeral joint laxity. Dynamic ultrasound is an alternative imaging method that may be used to measure glenohumeral laxity; however, validity and repeatability have not been examined.
  
  
  OBJECTIVE
  To determine criterion-related validity and repeatability of a sonographic imaging method for measuring glenohumeral laxity in asymptomatic shoulders.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  In experiment 1, 20 subjects were assessed for glenohumeral laxity using stress radiography and dynamic ultrasound. In the second experiment, 13 subjects were assessed for laxity in 2 separate test sessions using the dynamic ultrasound technique.
  
  
  RESULTS
  Correlational analysis between the sonographic and radiographic measures revealed an r = 0.79 (r(2) = 0.62), indicating excellent criterion-related validity for the sonographic imaging method. Test-retest repeatability was 0.72 and 0.85 for anterior and posterior translation, respectively, and interrater repeatability was 0.96 and 0.99 for anterior and posterior translation, respectively.
  
  
  CONCLUSIONS
  Dynamic ultrasound appears to be a valid and repeatable method for assessing glenohumeral laxity in a clinical setting.
  
  
  CONCLUSIONS
  Based on the results of this study, dynamic ultrasound is a repeatable and valid method for measuring glenohumeral laxity and therefore may be used as a viable replacement for stress radiography during assessments of glenohumeral laxity.
authors.affiliation: Sports Medicine Research Laboratory, University of Florida, 149 Florida Gymnasium, PO Box 118205, Gainesville, FL 32611-8205, USA. pborsa@hhp.ufl.edu
authors.forename: Paul A
authors.initials: PA
authors.lastname: Borsa
authors.forename: Jon A
authors.initials: JA
authors.lastname: Jacobson
authors.forename: Jason S
authors.initials: JS
authors.lastname: Scibek
authors.forename: Geoffrey C
authors.initials: GC
authors.lastname: Dover
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging*; D008297:Male; D015588:Observer Variation; D011859:Radiography; D015203:Reproducibility of Results; D012785:Shoulder Joint / Q000000981:diagnostic imaging*; D014463:Ultrasonography