title: The comparison of the empty can and full can techniques and a new diagonal horizontal adduction test for supraspinatus muscle testing using cross-sectional analysis through ultrasonography.
abstract: OBJECTIVE
  Several examination tests are currently used for diagnosing a supraspinatus lesion. The empty can (EC) test is currently considered the gold standard for testing, but full can (FC) testing is also utilized. Both of these tests do not fully eliminate the deltoid synergistic when resistance is applied. A new diagonal horizontal adduction (DHA) technique has been developed for evaluation of the supraspinatus that has not yet been compared with the existing techniques (EC/FC). Cross-sectional analysis (CSA) change during contraction as an ultrasonographic means of visualizing and measuring contraction of the supraspinatus has been reported previously.
  
  
  OBJECTIVE
  The purpose of this study was to use diagnostic musculoskeletal ultrasound (MSK) to compare CSA of the supraspinatus during the FC, EC, and the DHA tests.
  
  
  METHODS
  The supraspinatus muscle of 37 healthy, uninjured volunteers (21 males and 16 females, mean age of 26.9) were visualized and CSA was captured during 4 randomly assigned test positions (including control) using MSK.
  
  
  RESULTS
  A one-way Analysis of Variance with repeated measures of the mean CSA obtained in the testing positions was performed followed by least significant difference (LSD) for post-hoc analysis. Significant differences (p < 0.05) were found between the mean CSA of the controls and the CSA of each of the three testing procedures analyzed using the MSK. There were no significant differences (p < 0.05) in CSA between any of the three testing procedures.
  
  
  CONCLUSIONS
  In this study, MSK visualized and objectified activity of the supraspinatus muscle as evidenced through increased mean CSA when resisted. All the testing positions (FC, EC, and DHA) demonstrated significantly increased mean CSA of the muscle when isometrically contracted when compared to the resting control. The DHA procedure also elicited significant increase in CSA of the supraspinatus. However, no significant difference was found between the CSA of the DHA when compared to the FC and EC tests.
  
  
  METHODS
  Level 2.
authors.affiliation: University of Central Arkansas, Conway, AR, USA.
authors.forename: Steven W
authors.initials: SW
authors.lastname: Forbush
authors.forename: Douglas M
authors.initials: DM
authors.lastname: White
authors.forename: Wayne
authors.initials: W
authors.lastname: Smith
keywords: Cross‐sectional analysis; supraspinatus testing; ultrasound diagnostics