Long thoracic nerve
Nervus thoracicus longus
- Eponym: Bell’s external respiratory nerve
Definition
The long thoracic nerve, originating from the C5, C6, and C7 nerve roots of the brachial plexus, is a motor nerve that innervates the serratus anterior muscle. This muscle is crucial for scapular protraction and upward rotation, essential for arm elevation and punching movements. The nerve descends along the lateral chest wall on the surface of the serratus anterior muscle, making it vulnerable to injury from trauma or surgical procedures, which can result in scapular winging.
Clinical examination for long thoracic nerve integrity involves assessing serratus anterior muscle strength, with winging of the scapula indicating potential damage.
References
Lung K, Lui F. Anatomy, Thorax, Long Thoracic Nerve. [Updated 2023 Jul 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK535396/
