Safety analysis of percutaneous needle electrolysis: a study of needle composition, morphology, and electrical resistance.

Background: Percutaneous needle electrolysis (PNE) consists of a galvanic current combined with the insertion of a solid needle into the tissues of the musculoskeletal system. The application of a galvanic current through a needle can alter the morphology and composition during treatment application. This procedure may also provoke a localized temperature increase.

Aim: The aim was to evaluate the safety of the PNE procedure by analyzing possible alterations of the needles employed.

Methods: Physio Invasiva and AguPunt EPI brand needles, commonly used for the application of this technique, were analyzed in response to three different treatment protocols. Temperature changes were evaluated with the needles immersed in a test tube containing Ringer's solution, and electrical resistance was evaluated with a multimeter. The morphology of the needles, pre- and post-treatment, was examined with a scanning electron microscope (FEI Quanta 600), and the composition of the needles was evaluated using RX diffusion with Oxford Instruments software.

Results: Ringer's solution contained in the test tubes examined did not present temperature changes. No changes were observed in the needles under investigation with respect to electrical resistance, morphology, or composition with a protocol applying 3-mA intensity for 3 s and three applications. However, important morphological alterations were observed that affected needle composition after 50 applications (at 3 mA for 3 s).

Conclusion: PNE, applied according to conventional protocols, appeared to be safe and athermal, and did not provoke a loss of metal particles or modify the morphology of the needles used when studied in vitro.