A dermatome is an area of skin that gets its sensation from a specific spinal nerve root.
Spinal nerves exist in 31 pairs, one on each side of the spine.
What Is a Spinal Nerve Root?
These nerves provide sensory information and motor function (movement).
On the torso, dermatomes are horizontal stripes stacked on top of each other.
However, theyre a combination of angular and straight stripes on your arms and legs.
Dermatome mapping tends to be accurate but not all the time, though.
Symptoms include:
The rash is most common in the thoracic dermatomes.
If its in one or two neighboring dermatomes, its called localized zoster.
When it spreads across three or more of these sensory regions, its called disseminated zoster.
Some studies identify an especially high risk in people who have received organ transplants and those with blood-related cancers.
Spinal Cord Injury
Dermatomes are especially useful in determining the location of damage inspinal cord injuries.
Healthcare providers test one dermatome at a time during an exam.
The specific changes and location of symptoms can tell healthcare providers where the radiculopathy has occurred.
Summary
Dermatomes are areas on your skin attached to a specific nerve bundle.
These nerve bundles provide sensation to dermatomes.
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