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Bilateral four heads of the sternocleidomastoid muscle
So-Yeon Kim1, Han-Bin Jang, Jinu Kim
1Medical Course, School of Medicine, Jeju National University, Jeju, Jeju, Republic of Korea.
Abstract:
The sternocleidomastoid muscle shows a wide range of variations including supernumerary muscular heads. We found a rare variation in the sternocleidomastoid muscle with bilateral supernumerary heads in a 67-year-old Korean male cadaver. Bilateral four muscle bellies were recorded: two sternomastoids, one cleido-occipital and one cleido-mastoid occipital on the right side, and one sternomastoid, one cleido-occipital and two cleido-mastoids on the left side. The variation of bilateral four heads on sternocleidomastoid muscle is important to surgeons and anesthetists for clinical using.
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