Electrophysiological and Functional Effects of Shock Waves on the Sciatic Nerve of Rats
Journal
Ultrasound in Medicine and Biology
Journal Volume
34
Journal Issue
10
Pages
1688-1696
Date Issued
2008
Author(s)
Abstract
Extracorporeal shockwave therapy (ESWT) has been applied in lithotripsy and treatments of musculoskeletal disorders over the past decade, but its effects on peripheral nerves remain unclear. This study investigated the short-term effects of shockwaves on the sciatic nerve of rats. The nerves were surgically exposed and then stimulated with shockwaves at three intensities. We evaluated the motor nerve conduction velocity (MNCV) of treated sciatic nerves before, immediately after (day 0) and at 1, 4, 7 and 14 d after shockwave treatment. Two functional tests-the sciatic functional index and the withdrawal reflex latency-were evaluated before and at 1, 4, 7 and 14 d after shockwave application. The rats were sacrificed on days 0, 1, 4, 7 and 14 for morphologic observation. The degassed treatment group received high-intensity shockwave treatment using degassed normal saline as the contact medium, and MNCV was measured before and on days 0, 1, 4, 7 and 14. The sham group received the same procedure as the treatment groups (i.e., the surgical operation to expose the sciatic nerve) but with no shockwave treatment. The control group received no surgical operation or shockwave treatment. The results showed moderate decrease in the MNCV after shockwave treatment and damage to the myelin sheath of large-diameter myelinated fibers. The effect was largest (reduction to 60.9% of baseline MNCV) and of longest duration (7 to 14 d) in the high-intensity group. There were no significant changes in functional tests. These results indicated that direct application of shockwaves can induce reversible segmental demyelination in large-diameter fibers, with the electrophysiological changes being positively correlated with the intensity of the shockwaves. (E-mail: jjluh@ntu.edu.tw). ? 2008 World Federation for Ultrasound in Medicine & Biology.
SDGs
Other Subjects
Cell membranes; Electrophysiology; Fibers; Testing; Control Group; Extracorporeal shockwave therapy; Functional effects; Functional testing; Lithotripsy; Motor nerve conduction velocity; Motor-nerve conduction; Musculoskeletal disorders; Myelinated fibers; Peripheral nerve; Peripheral nerves; Sciatic functional index; Sciatic nerves; Shock waves; Short-term effects; Surgical operations; Treatment group; Withdrawal reflex latency; Rats; sodium chloride; animal experiment; animal model; animal tissue; article; control group; controlled study; correlation analysis; demyelination; ecchymosis; electrophysiology; extracorporeal lithotripsy; female; function test; hematoma; human; human cell; infection; latent period; male; morphology; motor nerve conduction; myelin sheath; myelinated nerve; nerve cell lesion; nerve stimulation; nonhuman; observational study; priority journal; rat; sciatic nerve; sham procedure; therapy effect; withdrawal reflex; Animals; Hot Temperature; Microscopy, Electron; Motor Neurons; Myelin Sheath; Nerve Regeneration; Neural Conduction; Rats; Rats, Wistar; Reaction Time; Reflex; Sciatic Nerve; Ultrasonic Therapy
Type
journal article