The cubital fossa (antecubital fossa) is a triangular depression located on the front side of the human elbow. It serves as a major transition zone connecting the upper arm to the forearm, housing important nerves, blood vessels, and tendons.
Boundaries Superior border: An imaginary line connecting the medial and lateral epicondyles of the humerus.
Medial border: The lateral edge of the pronator teres muscle.
Lateral border: The medial edge of the brachioradialis muscle.
Apex: Point where the medial and lateral boundaries meet inferiorly.
Floor: Formed by the brachialis and supinator muscles.
Roof: Formed by skin, superficial fascia, and the bicipital aponeurosis.
Radial nerve: Passes along the lateral border.
Biceps brachii tendon: Sits in the middle of the fossa.
Brachial artery: Lies just medial to the biceps tendon.
Median nerve: Located on the medial side of the brachial artery.
A useful mnemonic is TAN when read medial to lateral: Tendon, Artery, Nerve with the median nerve on the medial side. The radial nerve lies more laterally.