Dermatome Nerve Map – The term “dermatome” is a mix of two Ancient Greek words; “derma” meaning “skin”, and “tome”, implying “cutting” or “thin sector”. It is a location of skin which is innervated by the posterior (dorsal) root of a single back nerve. As posterior roots are organized in segments, dermatomes are. This is why the term “dermatome” describes the segmental innervation of the skin.
Dermatome Anatomy Wikipedia – Dermatome anatomy Wikipedia
Neighboring dermatomes typically, if not always overlap to some degree with each other, as the sensory peripheral branches representing one posterior root generally exceed the limit of their dermatome. The thin lines seen in the dermatome maps are more of a clinical guide than a real limit. Dermatome Nerve Map
This means that if a single back nerve is affected, there is likely still some degree of innervation to that section of skin coming from above and listed below. For a dermatome to be totally numb, typically two or 3 surrounding posterior roots need to be affected. In addition, it’s crucial to keep in mind that dermatomes undergo a large degree of interindividual variation. A graphical representation of all the dermatomes on a body surface area chart is referred to as a dermatome map. Dermatome Nerve Map
Dermatome maps
Dermatome maps portray the sensory distribution of each dermatome throughout the body. Clinicians can examine cutaneous sensation with a dermatome map as a way to localize lesions within central anxious tissue, injury to particular spinal nerves, and to figure out the level of the injury. A number of dermatome maps have actually been established for many years however are frequently clashing.
The most typically used dermatome maps in significant books are the Keegan and Garrett map (1948) which leans towards a developmental interpretation of this principle, and the Foerster map (1933) which correlates much better with medical practice. This article will review the dermatomes using both maps, determining and comparing the major differences between them.
Why Are Dermatomes Important?
To understand dermatomes, it is necessary to understand the anatomy of the spine. The spine is divided into 31 segments, each with a pair (right and left) of anterior and posterior nerve roots. The kinds of nerves in the anterior and posterior roots are different.
Anterior nerve roots are responsible for motor signals to the body, and posterior nerve roots get sensory signals like pain or other sensory symptoms. The anterior and posterior nerve roots integrate on each side to form the spinal nerves as they leave the vertebral canal (the bones of the spine, or foundation).