Table 3. The measurement position and method for scapular stabilizing and shoulder large muscles. Posture Transducer position Image Upper trapezius Prone Spinous process at the level of C6 Triangular shaped medial portion of the muscle Lower trapezius Prone Spinous process at the level of T8 Medial portions of the muscle belly Serratus anterior Side-lying Superior to the peak convexity of the most distal rib Between the superior and inferior echogenic fascial lines Supraspinatus Seated Center of the supraspinous fossa 2cm from the angle formed by the superior muscular fascia of the supraspinatus Infraspinatus Seated Center of the infraspinous fossa 2cm from the angle formed by the superior muscular fascia of the infraspinatus Rhomboid major Seated Center of two lines: the middle of the line from T2 to the root of the scapular spine and the middle of the line from T5 to the scapular inferior angle Vertical length between the inferior echogenic fascial line of the trapezius and the superior line of the posterior serratus Pectoralis major Stood Between third and fourth of costa under the clavicle midpoint Between the subcutaneous adipose tissue–muscle interface and the muscle–bone interface Middle deltoid Seated Superior surface of the acromion process of the scapula Quarter of the distance from acromion to the lateral epicondyle Side-lying: Side-lying with shoulder supported in 90° flexion