Students of medicine and nursing can benefit from using the mnemonic “DREADS” to memorize the essentials of the spinal cord and referred pain.
To help students remember, this graphic illustrates how primary afferent nociceptors travel from the periphery into the spinal cord via the dorsal root, where they release neurotransmitters that excite spinal neurons, converge on a large population of spinal neurons, and are ultimately controlled by a spinal segment of the dorsal root ganglion.
Referred pain is an essential notion that is often encountered in therapeutic practice, and this article underscores that fact. Students can recall the most important points and put them to use in their clinical practice by using this mnemonic.
The dorsal horn of the spinal gray matter is the final destination for primary afferent nociceptors once they exit the spinal column via the dorsal root. Referred pain is the result of spinal cord neurons being excited by neurotransmitters released by primary afferents in response to noxious stimuli.
Mislocalized pain is a common symptom of injury, and referred pain occurs when a patient experiences pain somewhere other than the area of the body that is innervated by the same spinal segment.
The Spinal Cord and Referred Pain Mnemonics :
- D: Dorsal root is where primary afferent nociceptors enter the spinal cord
- R: Release of neurotransmitters (glutamate, substance P, CGRP) excites spinal neurons
- E: Each primary afferent contacts many spinal neurons, leading to convergence
- A: All spinal neurons receive input from both skin and deep structures
- D: Determined by spinal segment of dorsal root ganglion supplying afferent innervation
- S: Spatial displacement of pain sensation from injury site is referred pain