Context: Scapular dyskinesis has been identified as a possible risk factor for injury in overhead athletes. There is a need to develop a simple, inexpensive, time-efficient field-based test that can establish the presence and severity of both scapular dyskinesis and its individual components in a musculoskeletal preparticipation screening. To ensure confidence in the test results, high reliability must be displayed. Objective: To establish the intertester and intratester reliability of a simple field-based screening tool for scapular dyskinesis. Design: Reliability study. Setting: Athletic therapy facilities. Participants: 15 physically active men (19.46 ± 0.63 y) free from any orthopedic or neurological disorders, recruited from a convenience sample of college students. Intervention: Testers underwent 3 training sessions where the instructions and scoring system of the test were explained, demonstrations of the tests were given, and opportunities to practice the test were provided. Three testers independently rated 3 trials, and the process was repeated at the same time the following week. Main Outcome Measures: Scapular dyskinesis was assessed using the following components: winging, loss/lack of control when lifting, loss/lack of control when lowering, and scapular asymmetry. A 0-3 rating (0 = no issue, 1 = slight issue, 2 = moderate issue, 3 = severe issue) was provided by the tester independently on each side separately and on scapular asymmetry. The intraclass correlation coefficients (ICCs), 95% confidence intervals, and standard error of measurement (SEM) were computed to establish reliability. Results: Excellent ICC values were found for intertester reliability (ICCs .80-1.00) and good to excellent intratester reliability (ICCs .60-1.00 for tester A, .63-1.00 for tester B, and .75-1.00 for tester C) for all components of the test. The SEM was not found to be clinically significant. Conclusions: The simple field-based screening tool developed to assess scapular dyskinesis demonstrates high reliability and so is a reliable tool to use in preparticipation screenings. Future research should establish its validity.
The authors are with the School of Health and Human Performance, Dublin City University, Dublin, Ireland. O'Connor is also with the Dept of Life and Physical Science in Athlone Inst of Technology.