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How are the 31 pairs of spinal nerves grouped by region?

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Diagram of a human figure showing the full nervous system, including the brain, spinal cord, and branching peripheral nerves throughout the body, with labels for each part. — human nervous system The conduction of electrochemical stimuli from sensory receptors in the human nervous system occurs via organized groups of specialized cells, consisting largely of neurons, various neural support cells, and tracts of nerve fibers.

In the human body, the 31 pairs of spinal nerves are organized into segments based on the region of the spinal cord from which they emerge. These nerves connect the spinal cord to specific areas of the body.12

The 31 pairs are grouped as follows:

Cervical (C): 8 pairs12
Thoracic (T): 12 pairs12
Lumbar (L): 5 pairs12
Sacral (S): 5 pairs12
Coccygeal (Coc): 1 pair12

Each of these nerves is associated with a dorsal root for sensory input and a ventral root for motor output.12