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Why does acute pain often begin with a sharp feeling and continue as a dull throbbing feeling?
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pain
Learn how the human body senses pain and reacts to it.
The dual-phase experience of acute pain is mediated by two distinct types of primary afferent nerve fibers that transmit signals to the spinal cord.1
- Sharp, initial pain: This is transmitted by A delta fibers. These are larger, myelinated fibers that conduct electrical impulses rapidly, resulting in the immediate, well-localized sensation of sharp pain.1
- Dull, throbbing pain: This follows the initial sensation and is transmitted by C fibers. These are smaller, unmyelinated fibers that conduct impulses more slowly. They are associated with the lingering, poorly localized, and often throbbing sensation that occurs after the first quick burst of pain.1
Together, these pathways ensure that the body receives both an immediate warning of injury and a sustained signal that encourages protective behavior during the healing process.1