Dermatome Nerve Chart – The term “dermatome” is a combination 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 too. 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 corresponding to one posterior root normally exceed the limit of their dermatome. As such, the thin lines seen in the dermatome maps are more of a clinical guide than a real border. Dermatome Nerve Chart
This implies that if a single spinal nerve is impacted, there is likely still some degree of innervation to that sector of skin originating from above and listed below. For a dermatome to be completely numb, usually two or three neighboring posterior roots need to be impacted. In addition, it’s essential to keep in mind that dermatomes go through a big degree of interindividual variation. A graphical representation of all the dermatomes on a body surface area chart is described as a dermatome map. Dermatome Nerve Chart
Dermatome maps
Dermatome maps illustrate the sensory circulation of each dermatome throughout the body. Clinicians can assess cutaneous sensation with a dermatome map as a method to localize sores within central anxious tissue, injury to particular back nerves, and to identify the degree of the injury. A number of dermatome maps have been developed over the years however are frequently conflicting.
The most commonly utilized dermatome maps in significant textbooks are the Keegan and Garrett map (1948) which leans towards a developmental interpretation of this concept, and the Foerster map (1933) which correlates much better with clinical practice. This post will evaluate the dermatomes using both maps, identifying and comparing the significant distinctions between them.
Why Are Dermatomes Important?
To understand dermatomes, it is very important to comprehend the anatomy of the spine. The spine is divided into 31 segments, each with a set (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 accountable for motor signals to the body, and posterior nerve roots get sensory signals like discomfort or other sensory signs. The posterior and anterior nerve roots integrate on each side to form the back nerves as they exit the vertebral canal (the bones of the spine, or backbone).