Scapulohumeral Rhythm: Why is it Important?
Scapulohumeral rhythm is described as the ratio of movement between the scapula and humerus. It is the synchronized movement with the scapula and humerus. The scapula plays a major roll in shoulder elevation. The scapula helps with upward rotation, posterior tilt, and lateral rotation. Without the scapula, the shoulder would not be able to elevate. The scapulohumeral rhythm needs to be correct in order for the shoulder to function properly. There are two joints involved in shoulder movement, the glenohumeral and scapulothoracic joints. For every three degrees of shoulder movement, there is one degree of movement at the scapulothoracic joint and two degrees of movement at the glenohumeral joint. Scapulohumeral rhythm is essential for full range of motion. The humeral head must rotate for full range of motion to occur. Between the two joints involved in scapulohumeral rhythm, there is joint congruency. The joint congruency in shoulder movement results in decrease in shear forces. Th...