Oblique Cord Under the Skin, Anterior View

Description

Positioned in anterior anatomical orientation at the proximal forearm, the oblique cord is rendered as a taut fibrous band running inferolaterally from the ulna (near the ulnar tuberosity, just distal to the coronoid process) to the radius (distal to the radial tuberosity), lying superficial to the proximal interosseous membrane. Nearby landmarks you would expect in this field include the biceps brachii tendon inserting on the radial tuberosity, the brachialis tendon on the ulnar tuberosity and coronoid process, and the pronator teres crossing obliquely from the medial epicondyle toward the lateral radius. Medially, the ulna remains the more fixed bone, while the radius sits lateral and rotates around it during pronation and supination. Small structure, big consequences. Functionally, the oblique cord is part of the proximal radioulnar syndesmosis and acts as an accessory stabilizer that limits distal translation of the radius relative to the ulna when axial load is transmitted through the wrist. That relationship becomes clinically concrete in an Essex-Lopresti pattern (radial head fracture with interosseous membrane disruption), where loss of longitudinal stability allows proximal radial migration and secondary ulnocarpal impaction if the radial head is not restored. Surgeons approaching the proximal radius from the anterior side (Henry approach) also use this region to orient themselves around the biceps tendon and the anterior neurovascular interval, and the oblique cord helps teach why the proximal interosseous membrane is not a uniform sheet. Use this asset for upper limb anatomy teaching in medical and physiotherapy curricula when discussing forearm rotation mechanics, the proximal radioulnar joint, and the concept of longitudinal forearm stability. It also fits orthopaedic texts and slide decks covering radial head trauma, interosseous membrane injuries, and preoperative planning around the cubital fossa and proximal radius. Anatomical accuracy verified by SciePro's Medical Advisory Board.