Electromyographic study of the trapezius (pars media) and rhomboideus major muscles in movements of the arm (part 1)

Abstract

The participation of the trapezius (pars media) and rhomboideus major muscles in free movements of abduction, adduction, flexion, extension and hyperextension of the arm was studied electromyographically. These muscles were active and synergic in all analysed movements, both acting with intensity that ranged from moderate to very marked.