A Rare Bilateral Variation of the Median Cubital Vein Traversing Deep to the Bicipital Aponeurosis

Abstract

Objective: To describe a rare anatomical variation of the median cubital vein (MCV) identified during human donor dissection and discuss its potential clinical implications for venipuncture and vascular access procedures.

Methods: Routine anatomical dissection of the upper limbs of a 78-year-old female donor was performed at a medical school anatomy laboratory. The superficial venous anatomy of the cubital fossa was examined, with particular attention to the course and relationships of the MCV relative to the bicipital aponeurosis and surrounding neurovascular structures.

Results: Dissection revealed a bilateral variation in which the MCV coursed deep to the bicipital aponeurosis rather than superficial to it, as is typically observed. The vein maintained its usual connections with the cephalic and basilic veins but passed beneath the aponeurotic layer on both sides. Previously documented cases of this variation have been limited to unilateral findings in male donors, making the present case the first reported bilateral occurrence in a female donor. The deeper location of the MCV may reduce venous visibility and palpability, potentially increasing the difficulty of venipuncture and placing the vein in closer proximity to the brachial artery and median nerve.

Conclusion: A median cubital vein located deep to the bicipital aponeurosis represents a rare anatomical variation with important clinical implications. Awareness of this configuration may help clinicians anticipate difficult venous access and reduce the risk of neurovascular injury. In such cases, ultrasound-guided vascular access may improve procedural success and patient safety, particularly in emergency or high-risk clinical settings.