What is n.axillaris?

N.axillaris, also known as the axillary nerve, is a nerve that arises from the posterior cords of the brachial plexus. It innervates the deltoid and teres minor muscles, as well as the skin overlying the lateral aspect of the shoulder. The axillary nerve is responsible for shoulder abduction and external rotation, as well as maintaining the position of the humeral head within the glenoid fossa during these movements. Injury to the axillary nerve can result in weakness or paralysis of the deltoid muscle, causing a decrease in shoulder abduction and external rotation.