Dermatomes are areas of skin that are innervated by single spinal nerve roots. They originate from somites, or embryonic tissue segments, that differentiate into dermatomes to give rise to the skin's connective tissue. While dermatome maps show general patterns, significant variations exist between individuals. Dermatomes are useful clinically for localizing neurologic issues like radiculopathy and revealing the origin of viral infections like shingles that affect spinal nerves.

1. Dermatomes
& some other relevant stuff..
1

2. Overview
The surface of the skin is divided into specific areas called dermatomes,
which are derived from the cells of a somite.
These cells differentiate into 3 regions /
1- Myotome ; gives rise to the skeletal musculature.
2-Dermatome ; gives rise to the connective tissue of the skin.
3-Sclerotome ; gives rise to the vertebrae
2

3. Dermatome
A dermatome is an area of skin in which sensory nerves derive from
a single spinal nerve root.
In the developing embryo, the dermatome arises from 1 of the 3
segments (somites) of the mesoderm, the middle layer of embryonic
tissue
3

4. 4

8. Variations?
The dermatomes along the arms and legs differ from the
pattern of the trunk dermatomes, because they run
longitudinally along the limbs. The general pattern is similar in
all people, but significant variations exist in dermatome maps
from person to person
8

9. Natural Variants
The dermatome is a basic concept, yet much variability
exists between dermatome maps in standard anatomy and
medical guideline textbooks.
9

11. Clinical significance
•
Dermatomes are useful to help localize neurologic
levels, particularly in radiculopathy.
•
Viruses that infect spinal nerves, such as herpes
zoster infections (shingles), can reveal their origin by
showing up as a painful dermatomic area.
11

13. Thank you
For further info. /
http://emedicine.medscape.com/article/1878388-overview#showall