Medial pectoral nerve

The medial pectoral nerve (also known as the medial anterior thoracic nerve) is (typically) a branch of the medial cord of the brachial plexus and is derived from spinal nerve roots C8-T1. It provides motor innervation to the pectoralis minor muscle, and the lower half (sternal part) of the pectoralis major muscle. It runs along the inferior border of the pectoralis minor muscle.

Damage to the medial pectoral nerve can result in inability to elevate the shoulder.

Anatomy

Origin

The medial pectoral nerve usually arises from the medial cord of the brachial plexus; it can however occasionally arise directly from the anterior division of the inferior trunk of the brachial plexus. It is derived from the eighth cervical (C8) and first thoracic (T1) spinal nerve roots.

The origin is situated posterior to the axillary artery.

Course and relations

It passes behind the first part of the axillary artery, curves forward between the axillary artery and vein, and unites in front of the artery with a filament from the lateral nerve.

It then enters the deep surface of the pectoralis minor muscle, where it divides into a number of branches, which supply the muscle.

Two or three branches pierce the muscle and end in the sternocostal head of the pectoralis major muscle. The medial pectoral nerve pierces both the pectoralis minor and the sternocostal head of the pectoralis major. The lateral pectoral nerve pierces only the clavicular head of the pectoralis major.

Clinical relevance

The medial pectoral nerve can be used as a donor nerve when reconstructing a damaged brachial plexus, or axillary nerve.

See also

• Lateral pectoral nerve

Additional images

References

This article incorporates text in the public domain from page 933 of the 20th edition of Gray's Anatomy (1918)

External links

• Anatomy photo:05:st-0511 at the SUNY Downstate Medical Center
• EatonHand ner-016
• MedEd at Loyola GrossAnatomy/dissector/practical/ue/ue15.html

1. Pectoralis minor
2. Lateral pectoral nerve
3. Pectoralis major
4. Brachial plexus
5. Pectoral nerve
6. Medial cord
7. Cervical spinal nerve 8
8. List of anatomy mnemonics
9. List of nerves of the human body
10. Outline of human anatomy
11. Upper limb
12. Anterior thoracic nerves
13. List of skeletal muscles of the human body
14. Outline of the human nervous system
15. Lateral cord
16. Serratus anterior muscle
17. Clavicle
18. Levator scapulae muscle
19. Scapula
20. Dog anatomy