This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
Various tumefactions, hypertrophic, rheumatic, and scrofulous, the result of simple chronic inflammation, or left behind after sprains or other injuries, have from time to time been treated by electricity in its different forms, and with more or less success.* The remedy probably operates as a simple excitant, hastening suppuration when the tendency is to that result, promoting the absorption of exuded fibrin and other secretions or depositions, and stimulating the disintegrating process, so as to favour resolution. Dr. Remak, of Berlin, states that he has found the constant current, produced by the arrangements of Daniell, Grove, and Bunsen, to have a powerful effect in resolving inflammatory tumours, by dilating the blood-vessels and promoting absorption. (Med. Times and Gaz., May, 1858. p. 479.) It is highly probable that cases of palsy, dependent on chronic inflammatory thickening of the spinal membranes or ligaments, or similar thickening from exudation in the theca of nervous trunks, or the passages which they traverse, might often be relieved by the galvanic influence brought to bear on these conditions, could their seat be precisely ascertained. Even strictures of the urethra are said to have been cured by the same means.
* Serous effusions may be removed in the same way by the promotion of absorption; and cases of hydrocele have been treated effectually by both galvanization and faradisation, after failure with iodine injections and the seton. The method of proceeding is to introduce two acupuncture needles into the fluid, one at one end of the sac, the other at the other, and then connecting these with the poles of the induction machine or galvanic battery. A mild current should be used at first, to be gradually increased until the patient complains. The operation should continue for about twenty minutes. Sometimes the swelling disappears within twenty-four hours; sometimes three or four operations are necessary. (Althaus, Med. T.and Gaz., Sept. 1862, p. 271.) - Note to the third edition.