A rare variation of the sternocleidomastoid muscle in a Turkish male cadaver: a case report of four clavicular heads on sternal head and an accessory head

Abstract

During a routine dissection at Hacettepe University Department of Anatomy a variation of the sternocleidomastoid muscle was found unilaterally on the left side, in a 75-year-old Turkish male cadaver. At first the skin was removed, then the superficial cervical fascia along with the platysma muscle. Four clavicular heads (CH1, 2, 3, 4) and an accessory head of sternal part were observed on the left side along with one typical sternal head. The length, width and distance from the anterior border of the trapezius muscle, the acromioclavicularjoint and the sternoclavicular joint of each muscle were measured twice by two investigators using a digital caliper. Surgeons need to study thoroughly about the variations before any neck surgeries. For a successful muscle flap harvesting, central venous catheterization, cervical examination and many other procedures involving the neck region, we need to aware of all kind of variation of the sternocleidomastoid muscle.

Keywords

• anatomy
• dissection
• neck surgery
• sternocleidomastoid muscle

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