Dermatome Map Or Chartdermatomes Definition Chart And Diagram – The term “dermatome” is a mix of 2 Ancient Greek words; “derma” suggesting “skin”, and “tome”, meaning “cutting” or “thin segment”. It is a location of skin which is innervated by the posterior (dorsal) root of a single spine nerve. As posterior roots are organized in segments, dermatomes are also. This is why the term “dermatome” refers to the segmental innervation of the skin.
Figure Dermatomes Clearly Visualized Contributed By The Public Domain StatPearls NCBI Bookshelf – Figure Dermatomes Clearly Visualized Contributed By The Public Domain StatPearls NCBI Bookshelf
Neighboring dermatomes often, if not constantly overlap to some degree with each other, as the sensory peripheral branches representing one posterior root normally go beyond the limit of their dermatome. The thin lines seen in the dermatome maps are more of a clinical guide than a real limit. Dermatome Map Or Chartdermatomes Definition Chart And Diagram
This means that if a single spinal nerve is impacted, there is most likely still some degree of innervation to that sector of skin coming from above and below. For a dermatome to be totally numb, generally 2 or three neighboring posterior roots require to be impacted. In addition, it’s important to note that dermatomes go through a big degree of interindividual variation. A graphical representation of all the dermatomes on a body surface chart is referred to as a dermatome map. Dermatome Map Or Chartdermatomes Definition Chart And Diagram
Dermatome maps
Dermatome maps illustrate the sensory distribution of each dermatome across the body. Clinicians can assess cutaneous experience with a dermatome map as a method to localize sores within main worried tissue, injury to particular back nerves, and to determine the degree of the injury. A number of dermatome maps have been developed throughout the years however are typically clashing.
The most commonly utilized dermatome maps in significant textbooks are the Keegan and Garrett map (1948) which leans towards a developmental analysis of this concept, and the Foerster map (1933) which correlates better with clinical practice. This post will evaluate the dermatomes using both maps, recognizing and comparing the major differences between them.
Why Are Dermatomes Important?
To understand dermatomes, it is important to understand the anatomy of the spinal column. The spine is divided into 31 sectors, each with a pair (right and left) of anterior and posterior nerve roots. The kinds of nerves in the anterior and posterior roots are various.
Anterior nerve roots are responsible for motor signals to the body, and posterior nerve roots receive sensory signals like pain or other sensory signs. The posterior and anterior nerve roots combine on each side to form the back nerves as they leave the vertebral canal (the bones of the spine, or backbone).