Early vs. Late Referral for Scapular Exercises in Shoulder Function After Neck Dissection

Shoulder abduction AROM is measured in degrees three times using a universal goniometer and full-circle manual protractor, with the subject supine, shoulder in lateral rotation, and palm facing anteriorly. The protractor fulcrum is placed on the anterior acromial process, one arm aligned with the midline of the sternum, and the other with the anterior midline of the humerus, while keeping the thorax immobile to prevent vertebral lateral flexion.

The modified lateral scapular slide test (MLSST) measures the medio-lateral displacement of the inferior scapular angle and asymmetry at three shoulder abduction angles. The distance between the inferior scapular angle and the spinous process of the seventh thoracic vertebra is measured three times on each side using a vernier caliper, and the average difference is calculated. The MLSST is conducted in three positions: arms at the sides (position 1), hands on hips (position 2), and holding a 1 kg dumbbell at 90° shoulder abduction with maximal internal rotation in the scapular plane (position 3).

For upper trapezius (UT) measurement, participants sit in a height-adjustable chair with back support, knees, and hips at 90°, feet on the floor, and hands resting on their thighs. The transducer is positioned parallel to the UT muscle at an oblique angle between C7 and the acromion, then moved laterally to capture the medial portion. For middle trapezius (MT) measurement, participants sit at the table edge with knees and hips at 90°, feet flat, and arms at their sides with elbows at 90° and palms down on a pillow. The transducer is placed over the middle third of a line between the acromion's posterolateral edge and the T1 spinous process, tilted forward and downward to visualize the MT's fascial borders.

EMG signals are recorded from the upper trapezius(UT), middle trapezius (MT), and lower trapezius (LT) at standardized landmarks. MVIC is measured before testing to prevent fatigue, with participants resisting manual force in UT, MT, and LT-specific positions, each followed by a 1-minute rest. During the task, participants sit with feet flat, holding a 1 kg dumbbell at 90° shoulder abduction with maximal internal rotation. They perform three repetitions, raising the arm in 3 seconds, holding for 5 seconds, and lowering in 3 seconds, with a 60-second rest between repetitions. Normalized RMS is expressed as %MVIC by averaging EMG data from the fifth second of each repetition and normalizing it to MVIC at 90° shoulder abduction.

Shoulder pain levels will be assessed during exercises using a 10-cm visual analog scale (VAS).

Upper extremity function is assessed using the Taiwan version of the DASH, a reliable 30-item self-report questionnaire where higher scores indicate greater disability.