Dermatomes Map Hand

Dermatomes Map HandThe term “dermatome” is a mix of two Ancient Greek words; “derma” meaning “skin”, and “tome”, implying “cutting” or “thin segment”. It is an area of skin which is innervated by the posterior (dorsal) root of a single spinal nerve. As posterior roots are arranged in segments, dermatomes are. This is why the term “dermatome” describes the segmental innervation of the skin.

Dermatomes Map Hand

Dermatomes Neurology Medbullets Step 1 – Dermatomes Neurology Medbullets Step 1

Surrounding dermatomes frequently, if not always overlap to some degree with each other, as the sensory peripheral branches representing one posterior root typically exceed the limit of their dermatome. As such, the thin lines seen in the dermatome maps are more of a scientific guide than a real boundary. Dermatomes Map Hand

This implies that if a single spine nerve is affected, there is most likely still some degree of innervation to that segment of skin coming from above and below. For a dermatome to be entirely numb, typically 2 or three neighboring posterior roots need to be affected. In addition, it’s essential to keep in mind that dermatomes go through a big degree of interindividual variation. A visual representation of all the dermatomes on a body surface chart is referred to as a dermatome map. Dermatomes Map Hand

Dermatome maps

Dermatome maps illustrate the sensory circulation of each dermatome across the body. Clinicians can examine cutaneous feeling with a dermatome map as a way to localize sores within main nervous tissue, injury to particular back nerves, and to determine the extent of the injury. A number of dermatome maps have actually been developed over the years but are often clashing.

The most typically utilized dermatome maps in significant books are the Keegan and Garrett map (1948) which leans towards a developmental analysis of this principle, and the Foerster map (1933) which associates better with medical practice. This post will evaluate the dermatomes using both maps, determining and comparing the major differences between them.

Why Are Dermatomes Important?

To understand dermatomes, it is essential to understand the anatomy of the spinal column. The spine is divided into 31 segments, each with a pair (right and left) of anterior and posterior nerve roots. The types of nerves in the posterior and anterior roots are various.

Anterior nerve roots are responsible for motor signals to the body, and posterior nerve roots get sensory signals like pain or other sensory signs. The anterior and posterior nerve roots integrate on each side to form the back nerves as they exit the vertebral canal (the bones of the spine, or backbone).