Axillary nerve

The axillary nerve ("armpit nerve") is a nerve of the brachial plexus . In humans it has its roots in the spinal cord between the 5th and 7th neck segment (C5-C6), in domestic animals in C6-C8.

course

The nerve runs together with the posterior circumflex artery ( caudalis instead of posterior in animals ) between the humerus and the long head of the triceps brachii muscle , above the teres major muscle on the outside of the shoulder (known as the " lateral axillary gap " in humans , in animals as proximal axillary space ).

Innervation area

The nerve motor innervates some shoulder muscles:

• Deltoid muscle
• Teres minor muscle
• Teres major muscle (more than an exception in humans, regularly in animals)

The terminal branch of the axillary nerve is sensitive. It is called the superior lateral brachial cutaneous nerve and innervates the skin of the lateral shoulder.

In domestic animals, the terminal branch also has the nervus cutaneus antebrachii cranialis , which supplies the front upper arm and the upper front section of the forearm.

clinic

The lateral axillary gap borders on the collum chirurgicum of the humerus. This part of the bone breaks particularly often. Therefore, the axillary nerve is at risk in the case of a fracture of the upper arm. It can be damaged by broken bones or by callus formation . With shoulder dislocations , the nerve can become overstretched. Further injuries can result from joint arthroscopy .

literature

• Martin Trepel: Neuroanatomy. Structure and function. 3rd revised edition. Urban & Fischer, Munich et al. 2004, ISBN 3-437-41297-3 .
• Franz-Viktor Salomon: nervous system, systema nervosum. In: Franz-Viktor Salomon, Hans Geyer, Uwe Gille (Ed.): Anatomy for veterinary medicine. Enke, Stuttgart 2004, ISBN 3-8304-1007-7 , pp. 464-577.