Measurement of scapular prominence in symptomatic dyskinesis using a novel scapulometer: reliability and the relationship to shoulder dysfunction
Journal
Journal of Shoulder and Elbow Surgery
Date Issued
2020
Author(s)
Abstract
Background: No previous studies have investigated whether the extent of scapular dyskinesis is associated with shoulder dysfunction. This study aimed (1) to establish the reliability of a scapulometer in patients with shoulder pain and (2) to investigate the related factors associated with shoulder dysfunction. Methods: One hundred participants with symptomatic scapular dyskinesis were recruited. Twenty-one participants were involved in the reliability study to test the intrarater and inter-rater reliabilities of the scapulometer in patients with shoulder pain. After demographic data and self-reported Flexilevel Scale of Shoulder Function (FLEX-SF) scores were recorded, all participants were measured with a scapulometer to determine the posterior displacement of the root of the spine (ROS) and the inferior angle (IFA) of the scapula from the thorax. Next, the participants performed 5 trials of bilateral scapular plane elevation for scapular kinematics and electromyographic (EMG) data collection. Stepwise multiple linear regressions were used to determine the relationships between self-reported FLEX-SF scores and potential factors. In addition to scapular displacement, pain level, scapular kinematics, and EMG data were included as independent variables. Results: The intrarater and inter-rater reliabilities of the scapulometer were excellent (intraclass correlation coefficient [ICC] = 0.93-0.97) and moderate to good (ICC = 0.74-0.81), respectively. The Bland-Altman plots showed no systematic bias between raters in the ROS and IFA measurements. Final stepwise multiple regression models showed that more ROS distance, higher serratus anterior activity, and lower pain level during arm elevation were associated with higher shoulder function (total R2 = 0.253). Conclusion: The reliability of the scapulometer in patients with shoulder pain is moderate to excellent. Scapular dyskinesis may be a compensatory strategy to avoid shoulder pain and improve shoulder function. ? 2020 Journal of Shoulder and Elbow Surgery Board of Trustees
Subjects
Diagnostic Study; function; kinematics; Level IV; muscle activation; regression; reliability; Scapular dyskinesis
SDGs
Other Subjects
adult; anatomic landmark; Article; diagnostic test accuracy study; electromyography; female; flexilevel scale of shoulder function; human; interrater reliability; intrarater reliability; kinematics; major clinical study; male; measurement error; priority journal; rating scale; scapula; scapular dyskinesis; scapular prominence; self report; serratus anterior muscle; shoulder disease; shoulder pain; skeletal muscle; thorax; trapezius muscle; biomechanics; devices; joint characteristics and functions; pathophysiology; physical examination; physiology; reproducibility; scapula; shoulder; Adult; Biomechanical Phenomena; Electromyography; Female; Humans; Male; Physical Examination; Range of Motion, Articular; Reproducibility of Results; Scapula; Shoulder Joint
Publisher
Mosby Inc.
Type
journal article