Intercostobrachial nerve

The intercostobrachial nerves are cutaneous branches of the intercostal nerves.The lateral cutaneous branch of the second intercostal nerve does not divide, like the others, into an anterior and a posterior branch; it is named the intercostobrachial nerve. It pierces the Intercostalis externus and the Serratus anterior, crosses the axilla to the medial side of the arm, and joins with a filament from the medial brachial cutaneous nerve. It then pierces the fascia, and supplies the skin of the upper half of the medial and posterior part of the arm, communicating with the posterior brachial cutaneous branch of the radial nerve. It is often the source of referred cardiac pain.A second intercostobrachial nerve is frequently given off from the lateral cutaneous branch of the third intercostal; it supplies filaments to the axilla and medial side of the arm.Cutaneous nerves of right upper extremity.Diagram of segmental distribution of the cutaneous nerves of the right upper extremity.InnervationThis article incorporates text in the public domain from page 946 of the 20th edition of Gray's Anatomy (1918)