Magma Theory: two visceral routes (severe IBS-C and obstructed second-stage labour) to fascial spasm propagation in fibromyalgia

The cause of fibromyalgia (FM) remains unexplained. Magma Theory proposes that sustained hypertonicity of a visceral canal, driven from the prefrontal cortex through autonomic pathways, ejects spasmodic force into surrounding fascia, producing soft-tissue stiffness and widespread pain and discomfort. Two routes are proposed: the alimentary canal in men and women with severe constipation-predominant irritable bowel syndrome (IBS-C), and the birth canal in women whose severe hypertonicity retards the second stage of labour. The underlying hypothesis was published in the author’s 2014 book and expanded in 2026. This preprint states the two sub-phenotypes explicitly, specifies falsifiable predictions, testable on standard clinical equipment, for tissue stiffness (shear-wave elastography, SWE), circulation and related symptoms in outlying tissues, and states that, on this hypothesis, men develop FM only through the first route and women through either, which is itself refutable. No new patient data are presented; this is a hypothesis, not established causation.