Measuring shoulder internal rotation range of motion: A comparison of 3 techniques

Objective: To compare the reliability of shoulder internal rotation (IR) range of motion (ROM) measured using 3 different methods: standard technique, manual scapular stabilization technique, and visual inspection technique. Design: Prospective study. Setting: Clinic-based sports medicine center. Participants: Convenience sample of 56 unimpaired high-school athlete volunteers. Interventions: Not applicable. Main Outcome Measures: Shoulder IR ROM was measured by using a digital inclinometer with each of the 3 techniques. All measurements were performed independently by 2 groups of examiners and repeated to determine intra- and interrater reliabilities. Results: IR ROM measurements obtained with the scapula stabilized or by visual inspection were significantly less than when measured with the standard technique (P=.001). Intrarater reliability was good or excellent for all 3 methods (intraclass correlation coefficients =.63-.71), was similar for the scapular stabilization and visual inspection techniques, and was superior to that previously reported for similar measurements. In general, interrater reliability was lower than intrarater reliability for all measurements. Conclusion: Because the visual inspection and scapular stabilized techniques control for accessory scapulothoracic motion, these techniques may represent more valid measures of glenohumeral motion than the standard technique. Both the visual inspection and scapular stabilized techniques exhibited equally acceptable reliability for clinical use. However, because the visual inspection technique may be applied by a single examiner, we recommend its use to measure shoulder IR ROM in the clinical setting.