Also called punctum nervosum, Erb’s point is a a landmark of the brachial plexus on the upper trunk, located about 1 inch (2.5 cm) above the clavicle at about the level of the sixth cervical vertebra.
It is located on the posterior border of the sternocleidomastoid muscle midway between its attachments to the mastoid process, and the sternum and clavicle.
Erb’s point is formed by the union of the C5 and C6 nerve roots, which later converge. Branches of suprascapular nerves and the nerve to the subclavius also merge. The merged nerve divides into the anterior and posterior division of C5 and C6.
Injury to Erb’s point is commonly sustained at birth or from a fall onto the shoulder.
The nerve roots normally involved are C5 and partly C6.
Symptoms include paralysis of the biceps, brachialis, and coracobrachialis, the brachioradialis and the deltoid.
The effect is called Erb’s palsy.
Electrical stimulation at Erb’s point causes contractions of the biceps, deltoid, and other arm muscles.
This point is used in recording of Somatosensory evoked potentials« Back to Glossary Index