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

Purpose: 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).

Methods: 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.

Results: 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.

Conclusions: The present results provided some evidence to support the positive and sustainable benefits of integrating motor control training into the workplace postures and motions.