Brachial Plexus - Peripheral Nerves

 Brachial Plexus (C5 – T1)

Peripheral sensory innervation.The in-nervation of the skin by peripheral nerves originating from the plexus differs from the segmental innervation. The regions supplied by individual nerves overlap at their margins. The region innervated by a single nerve is called the autonomic zone (dark blue), and the total area supplied by the nerve including the area cosupplied by adjacent nerves is called the maximum zone (light blue).

Clinical Note: Interruption of a nerve causescomplete insensibility (anesthesia) in the auto-nomic zone but only a decreased sensibility (hy-poesthesia) in the maximum zones.




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