Reliability and Validity of a Clinical Assessment Tool for Measuring Scapular Mobility in Healthy Subjects

Compensatory motion or position of the scapula during upper extremity movement has been called scapular dyskinesis. Scapular dyskinesis has been linked to shoulder pathologies such as multidirectional instability, impingement, and tendinopathy. Methods available to quantify scapular motion include three]dimensional motion analysis, objective clinical measurement methods, and observation. As the identified reference standard, 3D motion analysis lacks clinical utility through its expense and laboratory based set up. Observation of the scapula requires a trained eye and is subjective to each clinician, making it susceptible to poor replicability. Objective methods of scapular measurement have been investigated, primarily during scapular upward rotation. The evidence surrounding objective measurement of the scapula has identified gravity]referenced inclinometry as a reliable method for assessing scapular rotation up to 120 degrees of glenohumeral flexion. This information serves as the groundwork for this study, which aims to establish inclinometry as a viable and valid method for evaluating scapular rotation in the sagittal and transverse planes. The measurements obtained from the inclinometer will be compared to 3D motion analysis for measurement error and accuracy. By establishing inclinometry as a reliable method of assessing scapular motion, clinicians will have a more sensitive clinical tool to evaluate impairments of scapular positioning.