Long Thoracic Nerve
Description
Name
- Long Thoracic Nerve
- External respiratory nerve of Bell
- Posterior thoracic nerve
- Nerve to Serratus Anterior
- External Respiratory Nerve of Bell
- Posterior Thoracic Nerve
- Bell’s Nerve (less commonly used)
General Information
- Purely motor nerve which arises from the brachial plexus (roots C5–C7)
- Innervates the serratus anterior muscle
- Plays a key role in scapular stability and shoulder mechanics
- Has a long, superficial course, making it vulnerable to injury
Anatomic Course
- Originates from anterior rami of C5, C6, and C7 nerve roots
- C5–C6 roots often pass through the middle scalene muscle
- C7 contribution typically travels anterior to the scalene
- Runs posterior to the Clavicle, anterior to first Rib
- Courses as inferiorly as 8th-9th rib, descending the lateral chest wall
- Runs superficial to the serratus anterior muscle
- Travels along the ribs, providing segmental motor branches to the serratus anterior
Motor Innervation