The radial tuberosity is an oval roughened prominence on the medial surface of the proximal radius, approximately 2 cm distal to the radial head, at the junction of the radial neck and shaft. It is the insertion of the distal biceps brachii tendon on its posterior facet (for the tendon) and anterior facet (for the bicipital bursa). The tuberosity rotates between the ulna and the biceps tendon during supination and pronation, creating the mechanical advantage for bicipital supination.
The radial tuberosity is the endpoint of distal biceps tendon reattachment during surgical repair of distal biceps rupture. Anatomic reattachment to the posterior facet of the tuberosity restores the supination and flexion moment arms of the biceps. The anterior approach to the radial tuberosity requires identification and protection of the posterior interosseous nerve (radial nerve deep branch) which winds around the radial head and is at risk in the anterior interval. The two-incision approach (Boyd-Anderson) accesses the tuberosity through both anterior and posterior forearm exposures.
Sudden forced extension against a contracting elbow flexor avulses the biceps tendon from the radial tuberosity, producing a palpable gap in the antecubital fossa and Popeye deformity with weakness of supination greater than flexion, requiring surgical reattachment to the tuberosity within 2-3 weeks for optimal function.
A rare overuse injury from repetitive pronation-supination in rowers and racquet sport athletes produces anterior elbow pain with tenderness at the radial tuberosity level, diagnosed by MRI showing periosteal oedema and managed with activity restriction until healed.
