Does rehabilitation decrease shoulder muscle activity in fibromyalgia in work or housework tasks? An electromyographical study

Purpose: This study sought to investigate whether patients with fibromyalgia (FM) are able to perform a work task and home care tasks with less muscle activity, recorded as surface EMG, after a rehabilitation programme as compared to before rehabilitation. Method: Muscle activity in shoulder and arm muscles was measured with surface EMG during a job task and three housework tasks before and after an individually adjusted rehabilitation programme for 16 female patients with FM. Ten healthy women were measured in the same way. Pain intensity and perception of exertion were assessed with Borg's CR100 scale after every activity. Results: The patients decreased their muscle activity more than the healthy subjects did in the trapezius pars descendens of the non-dominant side during computer typing and ironing. A decrease in pain intensity and perceived exertion after the computer typing and ironing coincided with the decreased muscle activity. Conclusion: Patients with FM are able to learn to perform a work task and a home-care task with less muscle activity in trapezius pars descendens after a rehabilitation programme. Decreased pain intensity and perception of exertion may indicate that these two experiences accompany the decrease in muscle activity.