The tibial nerve derived from L4-S3 spinal segments. The bladder is innervated T10-L2 and S2-4. The pelvic floor is innervated by the pudendal nerve S2-4. Dry needling in the innervation field of the tibial nerve can reduce peripheral and central nervous system sensitization through the anti-inflammatory effects of the micro tissue injury from the needle and the subsequent physiologic effects of healing. With peripheral and central nervous system sensitization, the glial cells around nerves secretes inflammatory cytokines chronically. Dry needling can “break” this chronic peripheral and central neural inflammatory cycle.
Combined with Estim there are other mechanisms involved. With Estim, at the local level, there are activation endogenous opioids and activation of local sympathetic nerve fibers. At the CNS level, it causes stronger pattering in central pain matrices, increase fMRI signaling in supplemental brain areas, and increase activity in the periaqueductal grey area. Also, sensory stimulation of the pudendal nerve distribution can change tone in the pelvic floor muscles and in the bladder musculature.
Typical parameters for Estim are frequencies in the 4-10 Hz range, Pulse width of 100-150, and duration of seconds to 5+ minutes.
Most basic Estim devices have these parameters. The IO ES-130 is good device for dry needling because of its very gradual ramping of intensity. Some cheaper units ramp unevenly and can go from mild stimulation to very high with very small changes in the controls.
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