Figure 2.1 This image demonstrates the dermatomes.
Radicular pain is due to nerve compression. Dermatomes are skin maps that
indicate which area of the skin is being supplied with sensation by a specific
spinal nerve. This will allow your specialist to have a reasonable suspicion
about which nerve is being compressed if you have radicular pain. The fifth
cervical nerve root (leaving the spinal canal between the fourth and fifth cer-
vical vertebrae), for instance, is called C5 and extends from the shoulder to
the wrist on the inside of the arm, as demonstrated in the diagram. When
there is compression of this nerve root, you will experience pain over the area
supplied by that nerve.
Referred pain is not due to nerve compression and is a more vague and non-
specific pain which spreads to the head, shoulders, between the shoulder
blades and even behind the eyes.
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