What is the Difference Between Dermatomes and Peripheral Nerves

The key difference between dermatomes and peripheral nerves is that dermatomes are areas of skin that send signals to the brain by using the spinal nerves, while peripheral nerves are a part of the human nervous system that reside outside of the brain and spinal cord and relay information between the brain and rest of the body.

Dermatomes and peripheral nerves are two parts of the body associated with the human nervous system. The human nervous system consists of the central nervous system (brain and spinal cord) and peripheral nervous system. The central nervous system controls most of the functions in the body and mind. On the other hand, the peripheral nervous system performs three main functions. It conveys motor commands to all voluntary striated muscles in the body, carries information about the external world and body to the brain and spinal cord, and it regulates autonomic functions such as blood pressure or sweating.

CONTENTS

1. Overview and Key Difference
2. What are Dermatomes  
3. What are Peripheral Nerves
4. Similarities – Dermatomes and Peripheral Nerves
5. Dermatomes vs Peripheral Nerves in Tabular Form
6. Summary – Dermatomes vs Peripheral Nerves

What are Dermatomes?

Dermatomes are areas of skin that send signals to the brain using spinal nerves. These signals give rise to sensations involving temperature, pressure, and pain. The part of a nerve that exists in the spinal cord is known as the nerve root. Damage to a nerve root can trigger symptoms in the nerve’s corresponding dermatome. Spinal nerves exist in the spine in pairs. Normally, there are 31 pairs in total. Thirty of these have corresponding dermatomes. The exception is the C1 spinal nerve that does not have a corresponding dermatome. Moreover, each dermatome shares the label of its corresponding spinal nerve; for example, cervical nerves and their dermatome, thoracic nerves and their dermatome, lumbar nerves and their dermatome, sacral nerves and their dermatome, coccygeal nerves, and their dermatome.

The symptoms that occur within the dermatome sometimes indicate damage to the dermatome’s corresponding nerve. The location of these symptoms, therefore, may help doctors diagnose underlying medical conditions. Furthermore, some medical conditions that can affect the nerves and their corresponding dermatome are shingles, pinched nerves, and traumatic injury.

What are Peripheral Nerves?

Peripheral nerves are a part of the human nervous system that reside outside of the brain and spinal cord, relaying information between the brain and the rest of the body. These nerves are part of the peripheral nervous system. It is divided into two main parts: the autonomic nervous system (ANS) and the somatic nervous system (SNS). The autonomic nervous system controls involuntary bodily functions and regulates glands. On the other hand, the somatic nervous system controls muscle movement and relays information from ears, eyes, and skin to the central nervous system.

Moreover, there are three types of peripheral nerves: sensory, autonomic, and motor. Furthermore, peripheral nerve disorders distort the messages sent between the brain and the rest of the body. This can result in painful cramps, numbness, muscle weakness, and tingling. The disorders affecting peripheral nerves include Sjogren’s syndrome, lupus, rheumatoid arthritis, Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy, and vasculitis.

What are the Similarities Between Dermatomes and Peripheral Nerves?

• Dermatomes and peripheral nerves are two parts of the body associated with the human nervous system.
• Both parts may have sensory nerves and may control sensations.
• They play important functions in the body.
• Damages to both parts cause disorders.

What is the Difference Between Dermatomes and Peripheral Nerves?

Dermatomes are areas of skin that send signals to the brain using the spinal nerves, while peripheral nerves are a part of the human nervous system that resides outside of the brain and spinal cord, relaying information between the brain and the rest of the body. Thus, this is the key difference between dermatomes and peripheral nerves. Furthermore, dermatomes are connected to the central nervous system, while peripheral nerves are connected to the peripheral nervous system.

The below infographic presents the differences between dermatomes and peripheral nerves in tabular form for side by side comparison.

Summary – Dermatomes vs Peripheral Nerves

Dermatomes and peripheral nerves are two parts of the body associated with the human nervous system. Dermatomes are areas of skin that send signals to the brain by using the spinal nerves. On the other hand, peripheral nerves are part of the human nervous system that reside outside of the brain and spinal cord and relay information between the brain and the rest of the body. So, this is the summary of the difference between dermatomes and peripheral nerves.

Reference:

1. Seladi-Schulman, Jill. “Dermatomes Diagram: Spinal Nerves and Locations.” Healthline, Healthline Media, 13 June 2019.
2. Cherry, Kendra. “What You Should Know about the Peripheral Nervous System.” Verywell Mind, 8 Feb. 2022.

Image Courtesy:

1. “1611 Dermatomes-02” By OpenStax Anatomy and Physiology – (CC BY 4.0) via Commons Wikimedia
2. “Human Nervous System diagram” By Benevolent – Own work (CC BY-SA 4.0) via Commons Wikimedia