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Middle cervical ganglion
Diagram of the cervical sympathetic. ("Middle cervical ganglion" labeled at center right.)
The middle cervical ganglion is presumed to represent the union of the two sympathetic ganglia corresponding to cervical segments C5–C6 since its gray rami communicantes usually join the cervical spinal nerves C5–C6, however, the ganglion sometimes also contributes gray rami communicantes to spinal nerves C4 and C7.