Last updated: Sat, Aug 17, 2024
In the section The Pain System in Acute Injury earlier, a serious scratch developed a flare (area of redness), a wheal (slight surface swelling), and increased sensitivity (primary hyperalgesia) in an area surrounding the wound. All of that can be explained based on processes local to the injury.
An area of secondary sensitization also develops around a wound, outside the area of primary sensitization, and outside of the receptive fields of the neurons of the damaged area. This secondary area reacts with pain to light touch, but yet it is less able to feel a light touch as merely a touch, than an undamaged area. A slightly larger area is sensitive to punctate pressure, that is, pressure from a stimulus with a sharp edge. It is not hypersensitive to blunt pressure, however. Although the primary area is hypersensitive to heat, the secondary area isn't.
Within this section...
Secondary Stroking Hyperalgesia (Last updated: Sat, Aug 17, 2024)
Secondary Punctate Hyperalgesia (Last updated: Thu, Jun 22, 2017)
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Deep Tissue Injury (Last updated: Sat, Aug 17, 2024)