Long head of triceps supplied by axillary nerve

Komala NANJUNDAIAH, Shashanka

Abstract

The axillary nerve comes from the posterior cord of the brachial plexus at the level of the axilla and carries nerve fibers from C5 and C6. It supplies deltoid and teres minor. The radial nerve (C5–T1) is the largest branch of brachial plexus and is the continuation of the posterior cord. It supplies all the 3 heads of triceps brachii muscle by separate branches to each of the head. During routine dissection study and teaching to undergraduate students, we found bilateral variation in the innervation to long head of triceps in an adult male cadaver aged 60–70 years. The motor branch to the long head of the triceps was arising from the axillary nerve bilaterally, instead of its usual origin from radial nerve. Morphological and clinical implications of the variation are discussed.