Two Types of Innervation

• To say a nerve innervates a muscle means the nerve supplies either movement (motor innervation) or feeling (cutaneous or sensory innervation) to the area.
  
  

Motor Innervation

• For movement, the brachial plexus innervates all of the muscles of the upper limbs except the trapezius and levator scapula. This includes the muscles of the arm, shoulder, upper back and chest.
  
  

Examples of Motor Nerve Innervations

• At least 10 nerves in the brachial plexus innervate the upper limbs, including the ulnar nerve for the intrinsic muscles of the hand, the radial nerve for the extensor muscles of the forearm, the axillary nerve for the deltoid and teres minor, the long thoracic nerve for the serratus anterior muscle and the suprascapular nerve for the supraspinatus and infraspinatus.
  
  

Cutaneous Innervation

• For feeling, the brachial plexus innervates all of the upper limbs except the area of the armpit, an area just above the point of the shoulder and the back of the shoulder blade.
  
  

Examples of Cutaneous Innervations

• Nerve innervations for feeling include the musculocutaneous nerve for the outside of the forearm, the ulnar nerve for the little finger and half of the fourth finger, the median nerve for the other 3 1/2 fingers, the axillary nerve for the skin just below the point of the shoulder and the radial nerve for the skin on the back of the outside of the hand.