title: Glenohumeral rotation and scapular position adaptations after a single high school female sports season.
abstract: BACKGROUND
  Anterior instability and impingement are common in overhead athletes and have been associated with decreases in internal rotation (IR) and increases in external rotation (ER) motion. However, the chronology and the effect of different female sports on these conditions have yet to be determined.
  
  
  OBJECTIVE
  To measure glenohumeral IR and ER rotation, total range of motion, and scapular position in female overhead athletes over a single competitive season.
  
  
  METHODS
  Multiple group pretest-posttest study.
  
  
  METHODS
  High school.
  
  
  METHODS
  Thirty-six female overhead athletes (age = 15.29 +/- 1.18 years, height = 164.16 +/- 7.14 cm, mass = 58.24 +/- 9.54 kg) with no history of shoulder or elbow surgery participating in high school swimming, volleyball, or tennis.
  
  
  METHODS
  Participants were measured for all dependent variables at preseason and postseason.
  
  
  METHODS
  Participants were measured for glenohumeral IR and ER with the scapula stabilized. Total glenohumeral range of motion was calculated as the sum of IR and ER. Scapular upward rotation was measured at 0 degrees , 60 degrees , 90 degrees , and 120 degrees of glenohumeral abduction in the scapular plane, and scapular protraction was measured at 0 degrees , 45 degrees (hands on hips), and 90 degrees of glenohumeral abduction.
  
  
  RESULTS
  Internal rotation decreased from preseason to postseason (P = .012). Swimmers had less IR than both volleyball and tennis players (P = .001). External rotation also decreased in the swimmers (P = .001). Overall, preseason to postseason total motion decreased for athletes participating in swimming (P = .001) and tennis (P = .019). For all participants, preseason to postseason scapular protraction at 45 degrees glenohumeral abduction decreased (P = .007).
  
  
  CONCLUSIONS
  Female overhead athletes demonstrated decreases in IR after only one competitive season. Clinically, our results indicate that overhead athletes should be monitored for motion changes throughout their competitive seasons.
authors.affiliation: University of Delaware, Newark, DE, USA. sjthomas@udel.edu
authors.forename: Stephen John
authors.initials: SJ
authors.lastname: Thomas
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Swanik
authors.forename: Charles
authors.initials: C
authors.lastname: Swanik
authors.forename: Kellie C
authors.initials: KC
authors.lastname: Huxel