Nerves of the Trunk - Peripheral Nerves

 Nerves of the Trunk

In the trunk region, the original metamer-ism of the body can still be recognized through the arrangement of the ribs and their intercostal muscles. The thoracic nerves, too, fit in well with this segmental organization. Each of the twelve thoracic spinal nerves divides into a posterior branch (A1) and an anterior branch (A2).

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