Context: Scapular taping can offer clinical benefit to some patients with shoulder pain; however, the underlying mechanisms are unclear. Understanding these mechanisms may guide the development of treatment strategies for managing neuromusculoskeletal shoulder conditions. Objective: To examine the mechanisms underpinning the benefits of scapular taping. Design: Descriptive laboratory study. Setting: University laboratory. Patients or Other Participants: A total of 15 individuals (8 men, 7 women; age ¼ 31.0 6 12.4 years, height ¼ 170.9 6 7.6 cm, mass ¼ 73.8 6 14.4 kg) with no history of shoulder pain. Intervention(s): Scapular taping. Main Outcome Measure(s): Surface electromyography (EMG) was used to assess the (1) magnitude and onset of contraction of the upper trapezius (UT), lower trapezius (LT), and serratus anterior relative to the contraction of the middle deltoid during active shoulder flexion and abduction and (2) corticomotor excitability (amplitude of motor-evoked potentials from transcranial magnetic stimulation) of these muscles at rest and during isometric abduction. Active shoulder-flexion and shoulder-abduction range of motion were also evaluated. All outcomes were measured before taping, immediately after taping, 24 hours after taping with the original tape on, and 24 hours after taping with the tape removed. Results: Onset of contractions occurred earlier immediately after taping than before taping during abduction for the UT (34.18 6 118.91 milliseconds and 93.95 6 106.33 milliseconds, respectively, after middle deltoid contraction; P ¼ .02) and during flexion for the LT (110.02 6 109.83 milliseconds and 5.94 6 92.35 milliseconds, respectively, before middle deltoid contraction; P ¼ .06). These changes were not maintained 24 hours after taping. Mean motor-evoked potential onset of the middle deltoid was earlier at 24 hours after taping (tape on ¼ 7.20 6 4.33 milliseconds) than before taping (8.71 6 5.24 milliseconds, P ¼ .008). We observed no differences in peak root mean square EMG activity or corticomotor excitability of the scapular muscles among any time frames. Conclusions: Scapular taping was associated with the earlier onset of UT and LT contractions during shoulder abduction and flexion, respectively. Altered corticomotor excitability did not underpin earlier EMG onsets of activity after taping in this sample. Our findings suggested that the optimal time to engage in rehabilitative exercises to facilitate onset of trapezius contractions during shoulder movements may be immediately after tape application.
- Muscle contraction
- Physical therapy techniques
- Shoulder pain
- Transcranial magnetic stimulation