TENS: Is it effective in reducing spasticity in Multiple Sclerosis?

1. TENS: Is it effective in reducing spasticity in Multiple Sclerosis? The Ayrshire Multiple Sclerosis Service. Caledonian University, Glasgow. The Multiple Sclerosis Society. Linda Miller Senior Physiotherapist

2. TENS • Transcutaneuos Electrical Nerve Stimulation: Electrical stimulation of low intensity, high frequency with short pulse widths selectively stimulates large diameter (Group II), mechanosensative surface nerve endings. • Mechanisms of action: segmental inhibition, release of endogenous opiods, physiological blocking, placebo.

3. Spasticity & TENS • Evidence of change in neurophysiological measures post TENS. • Reduction in spasticity in stroke & SCI. • Limited research in MS. • Clinical experience of reduction in spasm.

4. Aims of the study • To determine whether TENS was effective in reducing spasticity in Multiple Sclerosis. • To determine whether TENS was effective for muscle spasm or pain associated with spasticity. • To determine whether application time has an impact on the overall effectiveness of TENS. • To establish protocols for future studies

5. Study Design • 32 patients from Ayrshire MS service. • Repeated crossover design. Subjects randomly assigned 2 groups • All subjects used TENS for 2 weeks, 60 min per day and for 2 weeks, 8 hrs per day. • Single blind (assessor). • TENS 100Hz, 0.125ms, continuous pulse over quadriceps muscle.

6. Study Design

7. Outcome Measures • Demographic data • Global Spasticity Score(Ash+PTR+ Clonus) • Modified Penne Spasm Score • Visual Analogue Score • Compliance diary • Questionnaire

8. Data Analysis • A 2 sample T - test was used to check the comparability of the demographic & baseline variables of the 2 groups (Mann-Whitney:not normal). • A 3-factor ANOVA(GSS) used to establish that there was no difference between 2 groups. • A paired Wilcoxin was performed on the before & after data (GSS,PSS,VAS) from both groups for 60 min & 8 hrs.

9. Results 1 • No significant difference between the 2 groups for baseline & demographic data • No sig diff between the groups (p=0.765) • No sig diff in the GSS following TENS (60 min & 8hrs) and in the PSS & VAS following TENS (60 min)

10. Results 2: However! • Mean scores reduced post TENS, with scores reducing following 8hrs >60min TENS. • Significant reduction in PSS & VAS following TENS (8hrs) p0.05. • Wide variability in all scores : more subjects with scores reduced after 8hrs:60min TENS.

11. Changes in GSS, PSS & VAS post TENS

12. Questionnaire Results • The majority of subjects felt TENS had reduced symptoms (88% for spasm). • 72% reported benefits lasting lasting 2-3 days after stopping TENS. • 81% indicated they would continue to use TENS. Most preferred to use <8 hrs • Long term follow up TENS(9 - 21mths) 56% still using.

13. Conclusion • No statistically significant reductions in spasticity although the majority of subjects demonstrated clinically significant reductions. • TENS is most effective for spasm & pain associated with spasticity. • TENS is more effective when used for longer applications. • TENS is well tolerated and easy to use.

14. Future ImplicationsThe potential for symptom reduction, combined with reduced medication-related complications and costs makes TENS a treatment worth considering in the overall management of people with mild to moderate spasticity in Multiple Sclerosis.