A 45-year-old male presents to the outpatient clinic for routine blood pressure monitoring. The physician places the blood pressure cuff over the arm and auscultates with a stethoscope over the cubital fossa. The structure marked **B** in the diagram is the site where Korotkoff sounds are heard during this measurement. Which of the following best describes the anatomical relationship of this structure to the surrounding contents of the cubital fossa?

Explanation

## Why "Lies medial to the biceps tendon and lateral to the median nerve" is right The brachial artery (marked **B**) in the cubital fossa has a precise anatomical position that is clinically critical for blood pressure measurement and venipuncture. It lies medial to the biceps tendon (structure **A**) and lateral to the median nerve (structure **C**). This relationship is remembered by the mnemonic "Really Need Beer To Be At My Nicest" (Radial Nerve, Biceps Tendon, Brachial Artery, Median Nerve), which lists the structures in lateral-to-medial order. The brachial artery's position in the middle of the cubital fossa makes it the ideal site for auscultation during blood pressure measurement and for venipuncture. The bicipital aponeurosis (structure **D**) overlies and protects the artery and median nerve from inadvertent injury during these procedures (Gray's Anatomy 42e, Ch 47). ## Why each distractor is wrong - **Lies lateral to the biceps tendon and medial to the median nerve**: This reverses the correct anatomical relationship. The brachial artery is medial to the biceps tendon, not lateral to it. - **Lies medial to both the biceps tendon and the median nerve**: While the artery is medial to the biceps tendon, it is lateral to (not medial to) the median nerve. This option confuses the position relative to the nerve. - **Lies lateral to both the biceps tendon and the median nerve**: This is entirely incorrect. The artery is medial to the biceps tendon, not lateral to it. **High-Yield:** In the cubital fossa, remember the lateral-to-medial order: Radial Nerve → Biceps Tendon → **Brachial Artery** → Median Nerve. The artery's central position makes it the standard site for BP measurement and blood sampling. [cite: Gray's Anatomy 42e, Ch 47]