Glenohumeral internal rotation deficits in the overhead varsity level athlete

• Author / Creator

  Chepeha, Judith

• Objectives: The objectives of this project were to determine whether shoulder internal rotation (IR), external rotation (ER) and horizontal adduction (HAd) range of motion (ROM) 1) could be reliably measured and 2) used to detect clinically meaningful differences between varsity level, overhead athletes and non-competitive University students. Thirdly, a randomized clinical trial was used to determine if a common shoulder stretch (i.e. sleeper stretch) was effective in increasing IR- and HAd-ROM limitations in overhead athletes. Methods:Study I - Thirty men and women (47 shoulders) between 22 and 51 years, underwent standard goniometric assessment of IR and ER in 90˚ of abduction and HAd. Two therapists performed blinded assessments to determine the standard error of measurement (SEM) and minimal detectable change (MDC) values for intra- and inter-rater shoulder ROM. Study II – Shoulder rotation and HAd-ROM values were compared between 66 overhead varsity athletes and 30 non-competitive university students. Independent t-tests determined whether shoulder ROM differences were statistically significant and beyond the SEM and MDC established in Study 1. Study III - Thirty-seven overhead athletes, identified with an internal rotation deficit ≥ 15° were randomized into a stretch or control group. Independent t-tests determined whether significant differences existed between the 2 study groups’ IR- and HAd-ROM after 8-weeks and 2-way repeated measures ANOVA tests were used to investigate the rate of change in IR- and HAd-ROM over the 8-week evaluation. Results:SEM values were ≤ 10˚ for all shoulder motions (IR, ER and HAd) in both within and between therapist comparisons. IR, ER and HAd-ROM were statistically and clinically different between the overhead athletes and non-competitive students; the greatest difference was in IR-ROM. Sub-group analyses amongst athletes found volleyball players had the greatest alteration of normal shoulder ROM. Significant increases in IR-ROM were detected at 4-weeks with further improvement at 8-weeks in the stretch group compared to the control group. Conclusions: Posterior shoulder flexibility can be reliably measured and is significantly different between overhead athletes and non-competitive university students. An 8-week stretch program in varsity-level overhead athletes identified as having an IR loss of ≥ 15˚ can successfully increase shoulder movement.

• Subjects / Keywords

  • Angles (Geometry)--Measurement--Case studies
  • Shoulder--Movements--Measurement--Case studies
  • Athletes--Physiology--Case studies
  • Shoulder joint--Movements--Measurement
  • Shoulder joint--Rotator cuff
  • Stretching exercises--Case studies
  • Athletes--Medical examinations--Case studies

• Graduation date

  Fall 2011

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R36136

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.