Prevalence of Scapular Dyskinesia Among Individuals with Stroke: A Cross-Sectional Study

Background: Normal scapulo-humeral rhythm relies on coordinated scapular upward rotation, posterior tilt and external rotation to maintain optimal shoulder mechanics. Stroke-related weakness, spasticity and trunk posture changes can cause scapular dyskinesia and understanding its prevalence in stroke can guide targeted rehabilitation programs. Objective: To determine the prevalence of scapular dyskinesia in individuals with stroke using the Scapular Balance Angle (SBA) and Lateral Scapular Slide Test (LSST). Methods: A cross-sectional observational study was conducted on 88 individuals with subacute and chronic middle cerebral artery stroke which were selected via purposive sampling. SBA was measured using goniometer and values ≥7° were considered as dyskinesia. LSST was performed at 0°, 45° and 90° of shoulder abduction and a side-to-side difference >1.5cm was considered as dyskinesia. Results: The sample comprised of 69 males and 19 females with a mean age of 57.74 ± 5.37 years. SBA ≥7° was observed in 42 participants (47.73%) with a mean SBA of 8.93 ± 1.09°. LSST scores revealed increasing dyskinesia prevalence with shoulder elevation: 32.95% at 0°, 43.18% at 45° and 53.41% at 90° of shoulder abduction. Participants at risk (1.0-1.5 cm difference) were most common at 90° (43.18%). Mean LSST values for dyskinesia group were highest at 90° (2.47 ± 0.27 cm) Conclusion: The findings of the present study revealed high prevalence of scapular dyskinesia in individuals with stroke, particularly at higher degrees of shoulder elevation reflecting underlying muscular weakness and altered neuromuscular control. Keywords: Scapular Dyskinesia, Scapular Balance Angle, Lateral Scapular Slide Test, Stroke.