Long Thoracic Nerve

Written by Max Bidewell

Last updated September 30, 2023 • 8 Revisions

The long thoracic nerve is a somatic motor nerve of the thoracic wall.

It supplies innervation to the serratus anterior muscle.

Premium Feature

3D Model

Premium Feature
Access this feature with premium.
Go Premium

Course

The long thoracic nerve originates from the brachial plexus, recieving fibres directly from the anterior rami of spinal nerves C5-7.

It descends posteriorly to the brachial plexus and anteriorly to the posterior scalene muscle.

The nerve continues distally deep to the clavicle and superficial to the first and second ribs before continuing along the anterolateral thoracic wall. It divides into its terminal branches at the surface of the serratus anterior muscle.

Fig 1
Course of the long thoracic nerve.

Premium Feature

Dissection Images

Motor Functions

The long thoracic nerve supplies motor innervation to the serratus anterior muscle. This muscle rotates the scapula, allowing the arm to be raised over 90 degrees. It also holds the scapula against the ribcage.

Damage to the long thoracic nerve can result in weakness of the serratus anterior, producing a characteristic “winged scapula” appearance.

Fig 2
The serratus anterior and pectoralis minor muscles.

Rate This Article