Median Nerve Arising from Three Roots

The brachial plexus is formed by the anterior rami of the lower four cervical and the first thoracic spinal nerves. The median is one of the five major nerves arising from the brachial plexus. It is usually formed by the union of two roots, one from the medial and the other from the lateral cord of the brachial plexus. During routine dissection of the axilla in a male cadaver, it was observed that the median nerves of both sides were formed by three roots. One root arose from the medial cord and the other two from the lateral cord. Knowledge of such variations is useful for doctors in their clinical practice in order to understand the anatomical basis of complicated clinical symptoms and signs.