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How Pain Starts: The Full Cascade

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Made with Eureka, a Nebulytic product. Illustrations are AI-generated and schematic; check the facts in the sources before relying on them. Made with Eureka, a Nebulytic product.

The question

Why does a long day of sitting with one hip hiked leave a deep, “caught” ache just above the right hip — as if bone, fat, muscle and nerve are all caught and stressed — when nothing has visibly torn?

The short answer

Pain is not a damage meter. Free nerve endings transduce mechanical, chemical and thermal stimuli into electrical signals, and the spinal cord and brain decide whether those signals become pain. Deconditioning and a sustained posture narrow the margin between ordinary load and tissue tolerance, and a sensitised nerve can fire at stretches it would normally ignore — which is why the ache can feel deep and “caught” without a single tear. ---

Sources

  1. Numbering follows `STORY-BRIEF.md` §8 so that the small on-screen footnote numbers match. In this single-scene cut, the on-screen notes point to **[1, 2]** (nociception and pain) and **[13–17]** (nerve mechanosensitivity, glide and blood flow). Sources marked *(not shown on screen)* support the wider brief and the scope notes in `FACT-CHECK.md`.
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  28. Carragee EJ, Tanner CM, Yang B, Brito JL, Truong T. “False-positive findings on lumbar discography. Reliability of subjective concordance assessment during provocative disc injection.” *Spine.* 1999;24(23):2542–2547. https://doi.org/10.1097/00007632-199912010-00017 *(not shown on screen)*
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