Which boundary forms the dorsal boundary of Viborg's Triangle?

Which boundary forms the dorsal boundary of Viborg's Triangle?

• A. The zygomatic arch
• B. The sternomastoid muscle
• C. The tendinous insertion of the sternocephalicus muscle
• D. The masseter muscle

Answer: (C)

Viborg's triangle has a clearly defined dorsal edge that is formed by the tendinous insertion of the sternocephalicus muscle. This tendon creates a firm, palpable border along the ventrolateral neck, making it a reliable landmark when approaching the neck for procedures. The other structures listed do not form this dorsal boundary: the zygomatic arch and the masseter muscle are part of the facial/skull region and jaw, not the ventral neck border described for Viborg's triangle; the sternomastoid (sternocleidomastoid) is a neck muscle but does not define the dorsal edge in this anatomical landmark.

Viborg's triangle has a clearly defined dorsal edge that is formed by the tendinous insertion of the sternocephalicus muscle. This tendon creates a firm, palpable border along the ventrolateral neck, making it a reliable landmark when approaching the neck for procedures. The other structures listed do not form this dorsal boundary: the zygomatic arch and the masseter muscle are part of the facial/skull region and jaw, not the ventral neck border described for Viborg's triangle; the sternomastoid (sternocleidomastoid) is a neck muscle but does not define the dorsal edge in this anatomical landmark.