Dermatomes — overview

Dermatomes are routes taken by spinal nerves as they leave the spinal cord and branch out to the body. If you are suffering from neck or back pain, learning about dermatomes may help you make the right treatment decisions to get back to a better quality of life.

Anatomy of the spinal column

To better understand dermatomes, it helps to start with an overview of the spinal column. The spinal column is divided into levels which are determined by the positions of the vertebrae. For example, the seven cervical (upper) vertebrae are labeled C1 to C7, while the five lumbar (lower) vertebrae are labeled L1 to L5. These level designations also apply to spinal nerves as they branch off the spinal cord.

From top to bottom, nerve roots branch off the spinal cord and travel through openings in the vertebrae called foramina. There are two nerve roots that branch off of each side at every vertebral level – one on each side of the vertebra. Eventually, the nerve roots branch out far enough to create a network of nerves throughout the body.

The role of dermatomes in medicine

Because dermatomes are the routes that nerves travel as they leave the spinal cord and branch out, dermatomes can be associated with the body’s sensory nerves (the sense of touch) or the motor nerves (the ability to move). Dermatome routes are significant because the nerves traveling along those pathways serve specific areas of the body, which can help physicians isolate and identify which specific nerves are malfunctioning.

Medical researchers have charted dermatomes throughout the body. Dermatome charts or maps are designed to illustrate bodily areas that are supplied by a single spinal nerve. Often, dermatome maps look like a rainbow-striped human body, where each color is associated with a spinal nerve in the cervical (C2 to C8), thoracic (T1 to T12), lumbar (L1 to L5) or sacral (S1 to S5) areas of the spinal column.

Dermatomes can be used to isolate problems in the spinal cord because pain in or around a dermatome can be traced back to a specific 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 physician will most likely feel the corresponding area of the spine to examine and identify the specific damaged nerve root.

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

  • Cervical (C2 to C7) — contains nerves corresponding to the neck, shoulders, arms and hands
  • Thoracic (T1 to T12) — contains nerves corresponding to the chest and abdomen
  • Lumbar (L1 to L5) — contains nerves corresponding to the hips, the front of the legs, the shins, knee caps and parts of the feet
  • Sacral (S1 to S5) — contains nerves corresponding to the genitals, buttocks, back of the legs and calves

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

Upon diagnosis by a physician, treatment for these issues 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, reach out to Laser Spine Institute. Our dedicated team of Spine Care Consultants can help you learn about our minimally invasive spine surgery which offers many advantages over traditional open spine procedures.

Contact us today for your no-cost MRI review* to see if you may be a potential candidate for our minimally invasive outpatient procedures.