case_images: PMC11785517_01
case_images: The mechanism of action of nerve blocks in the management of fibromyalgia. A peripheral stimulus activates the MTrPs in the muscle, causing it to contract/tighten and altering muscle cell metabolism via the release of mitochondrial reactive oxygen species. Mitochondrial dysfunction within the muscle cells leads to the increased production of proinflammatory cytokines, such as nerve growth factor and Il-6, which interact with nociceptors within the muscle cells. The proinflammatory cytokines activate the nociceptors of the muscle cells, triggering the opening of sodium channels to depolarize the plasma membrane and generating an action potential. The action potential propagates through the A-delta fibers and C-fibers to the spinal cord's dorsal horn, where they converge onto the WDR neurons. Neurotransmitters such as glutamate and substance P are released, activating the NMDA receptors on the postsynaptic neurons and driving CS. The postsynaptic signal then ascends the lateral spinothalamic tract to the brain's anterior insula. Here, increased levels of excitatory neurotransmitters enhance cross-connectivity within the DMN and suppress coactivation of the AN, resulting in persistent pain and cognitive disruption. The prohibition symbols indicate the direct sites where the peripheral nerve blocks inhibit pain signaling. Red down arrows represent the reduction of variables in the pain pathway, including action potential propagation, neurotransmitter release, and NMDA activation, achieved through peripheral nerve block intervention. AN: attentional network; DMN: default mode network; GABA: gamma-aminobutyric acid; Glu: glutamate; IL6: interleukin-6; mtROS: mitochondrial reactive oxygen species; MTrP: myofascial trigger point; NGF: nerve growth factor; NLRP3: nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3; NMDA: N-methyl-D-aspartate; NO: nitric oxide; PK: protein kinase; PL: phospholipases; subP: substance P; WDR: wide dynamic range. The image was created using Canva.com
case_images: cureus-0017-00000076740-i01.jpg
case_images: PMC11785517_01_cureus-0017-00000076740-i01.jpg
case_images: FIG1
case_images: The mechanism of action of nerve blocks in FM is shown in Figure 1.