Fig. 2. The experimental setup, showing the subject in the three shoulder positions. (A ) The original brachial plexus tension test position with the shoulder in 90° abduction and 90° lateral rotation; the shoulder girdle is repositioned to its neutral position by a gentle depression force of 30 N. The figure shows the load cell (1); the electrogoniometer of the elbow (2) and of the wrist (3); the amplifier and digital display of the load cell (4); the K100 amplifier of the electrogoniometers, including a base unit with LCD display (5a) and a patient unit (5b); the head restraint (6); the arm rest (7); and a handheld switch (8, not used in this study). (B ) The shoulder positioned in 90° abduction, no lateral rotation, but with fixation of the shoulder girdle in a neutral position. (C ) The shoulder positioned in abduction, no lateral rotation and no fixation of the shoulder girdle.