What is the difference between dermatome and myotome?
Are myotomes and dermatomes the same? This is one of the popular questions tossing the mind of students pursuing medical courses around the world. The lesson provides dermatomes and myotomes ppt for better understanding.
The core difference between dermatome and myotome is that dermatome is a specific area on the skin innervated by a specific spinal root whereas myotome is a specific group of muscles innervated by a particular spinal root.
What Is Dermatome?
A dermatome is a specific area on the skin of human anatomy supplied by branches of a single spinal sensory nerve root.
The single spinal sensory nerves enter the root nerve at the spinal cord and branches to the periphery of the body.
The role of these sensory nerves transmits the signal from the sensation to the spinal cord from a particular area of human anatomy.
Dermatomes are located in the 8 cervical, 12 thoracics, 5 lumbar, 5 sacral, and 1 coccygeal spinal nerves.
What Is Myotome?
A myotome is a group of muscles innervated by the nerves of a single spinal root. A myotome is further divided into a dorsal epaxial part and a ventral hypaxial part.
To gain a deeper understanding, you need to master myotomes chart so that you can locate them in the human body and their respective function.
Here is an example of the myotome map in human anatomy:
| Nerve Root | Myotome | Function |
| C5 | Deltoid muscle | Abduction of the arm at the shoulder |
| C6 | Biceps | Flexion of the arm at the elbow |
| C7 | Triceps | Extension of the arm at the elbow |
| C8 | Small muscles of the hand | Finger flexion |
| L4 | Quadriceps | Extension of the leg at the knee |
| L5 | Tibialis anterior | Upward flexion of the foot at the ankle |
| S1 | Gastrocnemius muscle | Downward flexion of the foot at the ankle |
Comparison Chart: Dermatome vs Myotome
| Basic Terms | Dermatome | Myotome |
| Meaning | It is an area of the skin innervated with a single spinal sensory nerve | It is a group of muscles innervated by a single spinal nerve |
| Significance | A region of the skin innervated by a nerve of a single spinal | A group of muscles innervated by a nerve of a single spinal |
| Correlation | Some dermatomes consist of overlapping regions innervated by more than one spinal nerve. | Some myotomes are innervated by more than one spinal nerve. |
| Role | Responsible for coordination of senses | Responsible for coordination of voluntary muscle movement |
Core Differences
- Dermatomes are located in the spinal cord while myotome is a group of spinal nerves that originated from the muscles.
- Dermatome refers to an area of the skin innervated by the nerves from a single spinal nerve root while myotome refers to a group of muscles innervated by the nerves of a single spinal root
- A dermatome is a region of skin innervated by a single spinal nerve whereas myotome is a group of muscles innervated by a single spinal nerve
- Dermatome comprise of overlapping regions innervated by more than one spinal nerve whereas myotome are innervated by more than one spinal nerve
- Dermatomes are responsible for the coordination of senses whereas myotomes are responsible for the coordination of voluntary muscular movement
Read More: Difference between Tendons and Ligaments
Similarities between Dermatome and Myotome
- Both are anatomical structures innervated by a single spinal nerve
- Both are innervated by sensory, motor and autonomic nerve
- Both are important in accessing the spinal lesion to ascertain spinal cord injury
Comparison Video
Summary
The core difference between dermatome and myotome is that dermatome is a particular area of the skin innervated by a single spinal nerve root whereas myotome is a group of muscles innervated by a single spinal nerve root.