Effects of combining ergonomic interventions and motor control exercises on muscle activity and kinematics in people with work-related neck-shoulder pain

This study compared the effects of "Ergomotor" intervention and conventional physiotherapy, on influencing the motor control in the neck-shoulder region in people with work-related neck-shoulder pain (WRNSP). 101 patients (age range 20-54 years) diagnosed with chronic WRNSP were randomized into control (CO) group (n = 50) and Ergomotor (EM) group (n = 51). Each group received a 12-week intervention. Participants in CO group received treatment for pain relief and general exercises. EM group received individualized motor control training and advice of ergonomic modifications at their workplaces. At post-intervention, EM group showed significant reduction of bilateral upper trapezius muscle activity during active neck movements (left: 40-35%, right: 35-27%) and functional tasks such as lifting a weight forward-backward (left: 31-21%, right: 22-14%) and upward-downward (left: 26-23%, right: 20-13%). Cervical erector spinae also showed significant decrease in muscle activity during some phases of the functional tasks (left: 13-6%, right: 10-2%). In contrast, CO group did not show such changes in muscle activity at post-intervention. EM group also showed significant increase in movement velocity and acceleration during active neck movements in all directions (from 18 to 31%), while CO group only showed significant increase in movement velocity in some directions. Both groups reported significant but similar reduction in pain scores, at post-intervention and 1-year follow-up. The present results provided some evidence to support the positive and sustainable benefits of integrating motor control training into the workplace postures and motions.