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Published on: February 10, 2015
The hidden cost of slouching : exploring scapulohumeral rhythm changes in forward-headed students
Sheenam Popli1, Vikas Kumar Lamba2, Rahul Kumar3
1Department of Physiotherapy, Suresh Gyan Vihar University, Jaipur, India.
Background:
Forward head posture (FHP) may alter shoulder biomechanics through changes in neuromuscular control and scapular positioning; however, its relationship with scapulohumeral rhythm (SHR) remains unclear in asymptomatic individuals. To examine the association between FHP and SHR during shoulder abduction and compare SHR across abduction ranges.
Methods:
A cross-sectional study was conducted among 207 college-going young adults (18-25 years). FHP was assessed using the craniovertebral angle (CVA) via a validated smartphone application. Participants were categorized into FHP (CVA <44°) and normal posture groups. Scapular upward rotation was measured using a modified digital inclinometer, and SHR was calculated as the ratio of glenohumeral motion to scapular rotation across 0-90° abduction. Spearman's correlation analysis was performed.
Results:
Mean CVA was 41.82 ± 3.47°. SHR followed a range-dependent pattern approximating a 2:1 ratio. A moderate positive association was observed between CVA and SHR in early and mid ranges (0°-60°) (r = 0.387-0.421, p < 0.01), weakening at higher ranges and becoming slightly negative at 75°-90° (r = -0.198, p < 0.05).
Conclusion:
FHP is associated with altered SHR, particularly in early and mid abduction. These findings support incorporating cervical and scapular assessment within a regional interdependence framework.
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