title: Clinical measurement of scapular upward rotation in response to acute subacromial pain.
abstract: METHODS
  Block-counterbalanced, repeated-measures crossover study.
  
  
  OBJECTIVE
  To assess scapular upward rotation positional adaptations to experimentally induced subacromial pain.
  
  
  BACKGROUND
  Existing subacromial pathology is often related to altered scapular kinematics during humeral elevation, such as decreased upward rotation and posterior tilting. These changes have the potential to limit subacromial space and mechanically impinge subacromial structures. Yet, it is unknown whether these changes are the cause or result of injury and what the acute effects of subacromial pain on scapular upward rotation may be.
  
  
  METHODS
  Subacromial pain was induced via hypertonic saline injection in 20 participants, aged 18 to 31 years. Scapular upward rotation was measured with a digital inclinometer at rest and at 30°, 60°, 90°, and 120° of humeral elevation during a painful condition and a pain-free condition. Repeated-measures analyses of variance were conducted for scapular upward rotation position, based on condition (pain or control) and humeral position. Post hoc testing was conducted with paired t tests as appropriate.
  
  
  RESULTS
  Scapular upward rotation during the pain condition was significantly increased (range of average increase, 3.5°-7.7°) compared to the control condition at all angles of humeral elevation tested.
  
  
  CONCLUSIONS
  Acute subacromial pain elicited an increase in scapular upward rotation at all angles of humeral elevation tested. This adaptation to acute experimental pain may provide protective compensation to subacromial structures during humeral elevation.
authors: Department of Physical Therapy, East Tennessee State University, Johnson City, TN 37604, USA. wassinger@etsu.edu
authors: Craig A
authors: CA
authors: Wassinger
authors: Gisela
authors: G
authors: Sole
authors: Hamish
authors: H
authors: Osborne
mesh_terms: D000293:Adolescent; D000328:Adult; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D016059:Range of Motion, Articular; D012399:Rotation; D012540:Scapula / Q000503:physiopathology*; D020069:Shoulder Pain / Q000503:physiopathology*; D055815:Young Adult