Effects of transcutaneous electrical nerve stimulation in patients with peripheral and central neuropathic pain.

OBJECTIVE To evaluate and compare the effects of transcutaneous electrical nerve stimulation (TENS) therapy on pain intensity and functional capacity in patients with either peripheral neuropathic pain or central neuropathic pain. METHODS A total of 40 patients (20 with peripheral neuropathic pain and 20 with central neuropathic pain) were included in this study. Pain severity, pain quality, and functional capacity were assessed with a visual analogue scale, a neuropathic pain scale, and the Brief Pain Inventory, respectively. A pre-post-treatment design was used. Semmes Weinstein monofilaments were used to evaluate touch sensation. Mild pressure was applied to provoke static mechanical allodynia. The presence of any severe and sharp pains upon pricking was considered a positive sign for hyperalgesia. The 2 groups of patients received 20/30-min sessions of TENS therapy over 4 weeks. RESULTS No significant differences were found between the 2 groups regarding the pre-treatment values for visual analogue scale, neuropathic pain scale, and Brief Pain Inventory. The pain parameters in both groups were significantly decreased by TENS therapy for 4 weeks (p < 0.05). The group with peripheral neuropathic pain presented more overall improvements than the group with central neuropathic pain (p < 0.05). CONCLUSION TENS therapy can be used successfully in clinical practice as an alternative or supportive treatment.