Trunk nerves (intercostal, sympathetic, vagus nerve)
Spinal ganglion (dorsal root ganglion)
Ganglion spinale (ganglion sensorium nervi spinalis)
- Origin
- Swelling in the posterior root, lying in the intervertebral foramen, one pair per segment
- Insertion
- The central process enters the cord through the posterior root, the peripheral process runs through the spinal nerve to the receptors
- Function
- Holds the pseudo-unipolar cell bodies of every sensory neuron in the body; no relay takes place here, the signal passes through without a synapse
- Innervation
- Somatosensory and viscerosensory
- Movement & chain
- Passes sensory signals on without a synapse
- Palpation
- Not palpable; the level is inferred from the dermatome in which the complaints sit
- Clinical
- The varicella zoster virus stays latent in the ganglion for life and on reactivation produces the dermatomal blisters of shingles, sometimes followed by postherpetic neuralgia. Also radicular pain from compression in the intervertebral foramen, and the ganglion as the target of pulsed radiofrequency treatment for chronic root pain.
- Segmental innervation
- One pair per segment, C1-Co1, so 31 pairs
- In clinical practice
- Recognising the dermatomal pattern of shingles and starting antiviral treatment in time, and watching for postherpetic neuralgia
- Region in the model
- Trunk nerves (intercostal, sympathetic, vagus nerve)