The effect of subcutaneous nerve stimulation (SCNS) on pain associated with osteoarthritis of the hip

Abstract

A novel form of subcutaneous nerve stimulation (SCNS) was recently introduced for the relief of chronic pain. We present a study using this form of SCNS applied over the radial, median and saphenous nerves in patients with clinically diagnosed osteoarthritis of the hip. Acceptable pain relief was obtained in 60% of patients receiving stimulation, however, comparable analgesia was achieved in a control group, who received no electrical stimulation through similarly placed needles. We suggest that these results may be explained by the ability of SCNS to evoke a placebo response. The efficacy of the placebo effect and the ethical implications of its use in clinical practice are discussed.

Efficacy of Transcutaneous Electrical Nerve Stimulation for Osteoarthritis of the Lower Extremities: a Meta-analysis

“…Six of these studies (RCTs) were included, involving 268 patients with osteoarthritis (see Appendix 2). [24][25][26][27][28][29] In these studies, no other interventions were prescribed concurrently in combination with the TENS, although patients were permitted to continue taking analgesic medication in all comparison groups. Four studies used a traditional type of TENS: CTENS versus placebo in a crossover study; 28 CTENS versus BTENS versus placebo in a double-blind, placebocontrolled; 26 ALTENS versus electro-acupuncture versus ice versus placebo in a randomised, singleblind, parallel group study; 29 and ALTENS versus placebo in a double-blind, placebo-controlled study.…”

“…Four studies used a traditional type of TENS: CTENS versus placebo in a crossover study; 28 CTENS versus BTENS versus placebo in a double-blind, placebocontrolled; 26 ALTENS versus electro-acupuncture versus ice versus placebo in a randomised, singleblind, parallel group study; 29 and ALTENS versus placebo in a double-blind, placebo-controlled study. 25 The two other studies 24,27 applied a form of TENS that did not fall into any one type (see definitions in introduction) but instead used pulse TENS that included settings with aspects of both CTENS and ALTENS: one study used a pulse rate of 20 Hz and pulse width of 100 ms versus placebo in a randomised, double-blind, placebo-controlled study; 24 and the other, a pulse rate of 32-50 Hz in a randomised, single-blind, parallel group study. 27 In these two studies the TENS application produced a tingling sensation (characteristic of CTENS) but no muscle contraction (characteristic of ALTENS).…”

“…26 Another examined the effects of CTENS versus placebo on change in pain intensity and change in analgesic medications used by patients. 28 The two studies that examined MIX TENS versus placebo 24,27 both evaluated improvement in pain intensity and effect on analgesia use, while one 24 also measured change in joint mobility. Improvement of pain intensity (measured by three different scales), change in functional status, goniometry, change in knee circumference, time to walk 50 feet, and change in joint and soft tissue tenderness were the outcomes of interest in the RCT comparing ALTENS with placebo.…”

“…27 Patients with osteoarthritis of both the hip and knee and who received MIX TENS did not, however, report significant pain relief either after 1 week of treatment or after up to 24 weeks of follow-up. 24 In another study, patients with osteoarthritis of the hip only and who received ALTENS reported significant pain reduction compared with placebo after 6 weeks of treatment. 25 Finally, while BTENS had no immediate effect on pain relief compared with placebo in patients with osteoarthritis of the knee, it did have a significant effect on length of pain relief (up to 24 h post-application) reported.…”

“…Additional terms for study design were employed to obtain comparative controlled studies including case-control, cohort, RCTs, and controlled clinical trials. The references listed in the included trials (Appendix 2 [24][25][26][27][28][29] were searched, and additional comments and data obtained from content experts. Peer-reviewed abstracts from conference proceedings and specialised journals were also included, as was information from scientific meetings and personal communications.…”