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Question 8
Anatomy → Blood vessels and nerves
Classification
Question
SSBAQuestion Header
During surgery in the upper rectus sheath, an arterial branch is traced superiorly to the level of the sixth costal cartilage where it arises as a terminal branch of another artery. Which parent artery is involved?
Question Stem
A) External iliac artery
B) Femoral artery
C) Internal thoracic artery
D) Subcostal artery
E) Thoracoacromial artery
B) Femoral artery
C) Internal thoracic artery
D) Subcostal artery
E) Thoracoacromial artery
Options
A
External iliac artery
B
Femoral artery
C
Internal thoracic artery
D
Subcostal artery
E
Thoracoacromial artery
Explanation
The superior epigastric artery arises at approximately the level of the sixth costal cartilage as one of the terminal branches of the internal thoracic artery. It then descends between the costal and xiphoid slips of the diaphragm, passes anterior to transversus thoracis and the upper fibres of transversus abdominis, and enters the rectus sheath. Within the sheath it anastomoses with the inferior epigastric artery, usually above the umbilicus. The inferior epigastric artery instead arises from the external iliac artery. Superficial abdominal-wall branches associated with the femoral artery have a different origin and course. Recognition of the superior epigastric artery's origin is therefore important when considering vascular supply to the upper rectus muscle and anterior abdominal wall.
Option Validity
A) The external iliac artery gives rise to the inferior, not superior, epigastric artery.
B) Femoral branches supply superficial components of the abdominal wall but do not give rise to the superior epigastric artery.
D) The subcostal artery contributes to lateral abdominal-wall supply but is not the parent vessel described.
E) The thoracoacromial artery is not of the superior epigastric artery.
Further Reading
Part 1 MRCOG Revision Notes and Sample SBAs. Cambridge University Press, 2020. Section 1: Anatomy, Chapter 1. https://doi.org/10.1017/9781108644396