All the tissues in your body emerge from three fundamental layers. Yup, going embryological on ya’ here. Your skin and your brain come from the same layer. The sensitivity of the skin is its ability to receive information, which is transmitted to the brain in a pattern mapped out in the dermatomes.
This map shows the neural pathways that connect areas of skin that are mainly supplied by the same spinal nerve – particularly the afferent nerve fibers from a single dorsal root of a spinal nerve – but the details aren’t particularly important here.
However, it is important to understand that dermatomes are REALLY useful. Why?
“Dermatomes are useful to help localize neurologic levels, particularly in radiculopathy. Effacement or encroachment of a spinal nerve may or may not exhibit symptoms in the dermatomic area covered by the compressed nerve roots in addition to weakness, or deep tendon reflex loss.”1
What the heck does that mean? It means that when the nervous system is not well connected to an area of skin, that spot of skin might show symptoms. These could include things like a tendency to get irritated more or less easily, rashes, acne, psoriasis, hair loss, dryness or oiliness, and colour changes. In the case of shingles, the viral infection at the spinal level will spread over one or two dermatomes, usually on the torso.
When I’m looking for clues as to where the issue might be, the skin can offer a lot of information. These include fascial restrictions, blood supply, temperature, colour, texture, callous formation, as well as dozens of others. All this information can get overwhelming, but skin effects across a dermatome pattern can be a straight and clearly lit path leading back to the spine that helps therapeutic interventions avoid just treating symptoms. Small details can become big pictures if looked at from the right angle.
1 Dermatomes Anatomy Author: Stephen Kishner, MD, MHA; Chief Editor: Thomas R Gest, PhD https://emedicine.medscape.com/article/1878388-overview
All Integrative Movement Therapy services are provided under the scope of practice of Registered Massage Therapy in Ontario as per the regulations of the CMTO, and are thus eligible for insurance coverage for massage therapy.