What are dermatomes?

Dermatomes are defined as areas of the skin that are affected by a spinal nerve. Since dermatomes describe the routes that nerves travel as they leave the spinal cord and branch out, dermatomes can be associated with the body’s sensory nerves. Dermatome routes are significant because the nerves traveling along those pathways serve specific areas of the body, which can help doctors isolate and identify which specific nerves are malfunctioning. If you are suffering from neck or back pain, learning about dermatomes in the following article may help you make the right treatment decision to get you back to a better quality of life.

Where are dermatomes located in the spinal column?

To better understand dermatomes, it helps to start with an overview of the spinal column anatomy. The spinal column is divided into levels which are determined by the positions of the vertebra. These level designations also apply to spinal sensory nerves as they branch off the spinal cord.

Researchers have charted dermatomes throughout the body. Dermatome maps are designed to illustrate bodily areas that are supplied by a single spinal sensory nerve root. Dermatome maps typically look like a rainbow-striped human body, where each color is associated with a spinal nerve in the cervical (C2 to C7), thoracic (T1 to T12), lumbar (L1 to L5) or sacral (S1 to S5) area of the spinal column.

The spinal nerves that control the dermatomes are located along the vertebrae as follows:

  • The cervical spine (C2 to C7) — contains nerves corresponding to the neck, shoulders, arms and hands
  • The thoracic spine (T1 to T12) — contains nerves corresponding to the chest and abdomen
  • The lumbar spine (L1 to L5) — contains nerves corresponding to the hips, the front of the legs, the shins, knee caps and parts of the feet
  • The sacral spine (S1 to S5) — contains nerves corresponding to the genitals, buttocks, back of the legs and calves

From top to bottom, nerve roots branch off the spinal cord and travel through openings in a long hollow canal formed by the vertebral foramina, which acts as an opening in the bone. There are two nerve roots that branch off at every vertebral level — one on each side of the vertebra. Eventually, the nerve roots branch out far enough from the spinal cord to create a network of nerves throughout the body.

The role of dermatomes in medicine

Dermatomes can be used to isolate problems in the spinal cord because the pain in or around a dermatome, can be traced back to a specific sensory nerve root that is damaged, trapped or constricted. Dermatome pain mapping can also help to isolate viruses that are infecting the spinal nerves, such as shingles. When dermatome pain, numbness, tingling or weakness is identified, a doctor will most likely examine the corresponding area of the spine and identify the specific damaged nerve root.

Symptoms within one or more dermatomes can indicate the affected region of the spine. For instance, radiculopathy or radiating leg pain can indicate a problem with the nerve roots in the lumbar spine. This could indicate sciatica, which is often caused by compression of the sciatic nerve.

Treating spine conditions that affect dermatomes

Upon diagnosis by a doctor, treatment for these issues detected by dermatomes generally includes rest, physical therapy, pain medication or steroidal injections. If these conservative treatments prove ineffective and you are concerned about undergoing traditional open back surgery, contact Laser Spine Institute so we can help guide you on your next step toward finding pain relief. Our dedicated team can help you learn about our minimally invasive spine surgery, which is a safer and effective alternative to traditional open spine procedures. ^

We have helped more than 75,000 patients find relief from their chronic neck and back conditions since 2005. Reach out to Laser Spine Institute today for your no-cost MRI review* to see if you may be a potential candidate for our minimally invasive outpatient procedures.