Transcutaneous Electrical Nerve Stimulation for Phantom Pain and Stump Pain in Adult Amputees

Following amputation, 50% to 90% of individuals experience phantom and/or stump pain. Transcutaneous electrical nerve stimulation (TENS) may prove to be a useful adjunct analgesic intervention, although a recent systematic review was unable to judge effectiveness owing to lack of quality evidence. The aim of this pilot study was to gather data on the effect of TENS on phantom pain and stump pain at rest and on movement. Ten individuals with a transtibial amputation and persistent moderate-to-severe phantom and/or stump pain were recruited. Inclusion criteria was a baseline pain score of 3 using 0 to 10 numerical rating scale (NRS). TENS was applied for 60minutes to generate a strong but comfortable TENS sensation at the site of stump pain or projected into the site of phantom pain. Outcomes at rest and on movement before and during TENS at 30minutes and 60minutes were changes in the intensities of pain, nonpainful phantom sensation, and prosthesis embodiment. Mean (SD) pain intensity scores were reduced by 1.8 (1.6) at rest (P<0.05) and 3.9 (1.9) on movement (P<0.05) after 60minutes of TENS. For five participants, it was possible to project TENS sensation into the phantom limb by placing the electrodes over transected afferent nerves. Nonpainful phantom sensations and prosthesis embodiment remained unchanged. This study has demonstrated that TENS has potential for reducing phantom pain and stump pain at rest and on movement. Projecting TENS sensation into the phantom limb might facilitate perceptual embodiment of prosthetic limbs. The findings support the delivery of a feasibility trial.