i wonder if it is because every trial for every type of medication or device for peripheral neuropathy is only tested on people who have PN due to diabetes. The reason of course they do the tests on diabetics is because they know the cause of their pn so that variable in testing is controlled. When you read the results however, it states that the product or drug was effective in treating some aspect of diabetic neuropathy. Those of us with other causes are left out in the cold and therefore perhaps those devices or treatments are not recognized as being effective for our type cause of PN.