The cubital fossa, antecubital fossa, chelidon, inside of elbow, or, humorously, wagina or cough-into, is the area on the anterior side of the upper part between the arm and forearm of a human or other hominid animals. It lies anteriorly to the elbow (antecubital) (Latin ) when in standard anatomical position. The cubital fossa is a triangular area having three borders.
Boundaries
- superior (proximal) boundary – an imaginary horizontal line connecting the medial epicondyle of the humerus to the lateral epicondyle of the humerus
- medial (ulnar) boundary – lateral border of pronator teres muscle originating from the medial epicondyle of the humerus.
- lateral (radial) boundary – medial border of brachioradialis muscle originating from the lateral supraepicondylar ridge of the humerus.
- apex – it is directed inferiorly, and is formed by the meeting point of the lateral and medial boundaries
- superficial boundary (roof) – skin, superficial fascia containing the median cubital vein, the lateral cutaneous nerve of the forearm and the medial cutaneous nerve of the forearm, deep fascia reinforced by the bicipital aponeurosis (a sheet of tendon-like material that arises from the tendon of the biceps brachii)
- deep boundary (floor) – brachialis and supinator muscles
Contents
The cubital fossa contains four main vertical structures (from lateral to medial):
- The radial nerve passes underneath the brachioradialis muscle where it divides into deep and superficial branches. It is not always considered part of the cubital fossa but is in the vicinity.