In Brief:
Neuropathologic methods were used to compare the consequences of heating rat dorsal root ganglions and sciatic nerve to 42°C with pulsed radiofrequency energy, continuous radiofrequency energy, or thermal (heat probe) energy for 120 seconds. This was done to mimic a new clinical technique being used to treat low back and other forms of spinal pain, to test the safety of the therapy, and to determine whether tissue damage is a part of the mechanism of pain relief. The results indicate that, while there are transient changes in the hydration of the nerve and activation of fibroblasts that result in the deposition of epineurial and endoneurial collagen, there is no significant injury to nerve fibers, DRG neurons, or their support cells.
