External jugular vein passing through triangle formed by tendon of cleido- occipitalis cervicalis muscle, trapezius muscle and clavicle – a case report

Introduction The venous drainage of head and neck is divided into superficial and deep jugular systems. The deep jugular system consists of internal jugular vein and the superficial system consists of external and anterior jugular vein. External jugular vein is formed by the union of the posterior division of retromandibular vein and the posterior auricular vein below the ear in the substance of parotid gland [1]. It then passes superficial to sternocleidomastoid muscle and pierces the investing layer of deep cervical fascia 2.5 cm above the midpoint of clavicle and finally drains into subclavian vein [2]. External jugular vein is used in various procedures like transjugular liver biopsy, catheterization for hemodialysis, etc. Therefore any variation in external jugular vein should be kept in mind by the surgeons, radiologist, plastic surgeons. On the other hand, trapezius is a muscle of back forming the posterior boundary of posterior triangle of neck and is supplied by spinal accessory nerve.