An unusual bilateral sternalis muscle

In the current study, we present a bilateral sternalis muscle, which was found during routine dissection of a 64 years-old Caucasian male cadaver. At the right side, the muscle had an unusual morphology, namely it consisted of three almost parallel strap-like muscle slips. Moreover, we discuss the innervation, origin and incidence of this variation, which are under controversy, as well as its clinical relevance.