Nerve plexus
A nerve plexus is a plexus (branching network) of intersecting nerves. A nerve plexus is composed of afferent and efferent fibers that arise from the merging of the anterior rami of spinal nerves and blood vessels. There are five spinal nerve plexuses, except in the thoracic region, as well as other forms of autonomic plexuses, many of which are a part of the enteric nervous system. The nerves that arise from the plexuses provide both somatosensory and motor functions to the muscles. These functions include muscle contraction, the maintenance of body coordination and control, and the reaction to sensations such as heat, cold, pain, pressure, etc.
Spinal Plexuses
Cervical plexus - serves the head, neck and shoulders
Brachial plexus - serves the chest, shoulders, arms and hands
Lumbar plexus - serves the back, abdomen, groin, thighs, knees, and calves
Sacral plexus - serves the pelvis, buttocks, genitals, thighs, calves, and feet
Coccygeal plexus - serves a small region over the coccyx
Autonomic Plexuses
Celiac plexus (solar plexus) - serves internal organs
Auerbach's plexus - serves the gastrointestinal tract
Meissner's plexus (submucosal plexus) - serves the gastrointestinal tract