Examination of electrode placements and stimulating parameters in treating chronic pain with conventional transcutaneous electrical nerve stimulation (TENS).

Conventional transcutaneous electrical nerve stimulation was applied to 114 patients diagnosed as having peripheral neuropathy (N = 18), peripheral nerve injury (N = 21), radiculopathy (N = 36) and musculoskeletal disorders (N = 39) to determine optimal electrode placements and stimulation parameters for pain relief. Treatment outcomes were assessed primarily through evaluation of the present pain intensity (PPI) rating scale, Immediate improvements in PPI scores occurred in patients in all these diagnostic categories. One month follow-up data on 25 subjects showed that improvement was of limited duration. No clear correlation between stimulation parameters or electrode placements and pain relief was ascertained. In certain instances (subjects with radiculopathy or peripheral nerve injury) a positive relationship existed between higher intensity stimulation and amelioration of pain. Greater pain relief was reported among patients with minimal previous medical or surgical treatment in every diagnostic group.