An 11-year-old boy falls down the stairs. A physician examines a radiograph of the boy's shoulder region. If the structure indicated by the letter B is fractured, which of the following structures is most likely injured?: (A) Musculocutaneous nerve, (B) Radial nerve, (C) Deep brachial artery, (D) Posterior humeral circumflex artery
Answer is D. (d) Fracture of the surgical neck of the humerus occurs commonly and damages the axillary nerve and the posterior humeral circumflex artery.