Info Scapulohumeral Rhythm
In the salubrious shoulder, a natural kinematics rhythm/timing exists betwixt glenohumeral ABD in addition to scapulothoracic lateral rotation. After thirty degrees of abduction this beat is 2:1, pregnant that for each iii degrees of abduction, two degrees hand inwards the glenohumeral articulation in addition to one aeroplane occurs inwards the scapulothoracic joint.
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