Is TENS efficient?

[bernard]

I started, in 1997, a clinical study about efficiency of TENS (sinusoidal signal).

I hypothesized that all data collected will fit in a general rule if the collection is sufficiently large enough?

In order to be able to compare, without dispute, the collected data, it was decided :

to use for all the patients, the same electrodes (15 cm²).
to use the same frequency of care (60 Hz).
that the patient indicates to the expert, any variation of sensation.
if the sensation decreases, the expert increases tension to find the preceding one.
if the feeling is painful, the tension is decreased. The value of beginning is re-initialized.
The average duration of treatment is 15 minutes.
no measurement is discarded.

results

We collected 16 227 measurements:

rachis 5,769 35.55 %
upper limb 2,927 18.04 %
lower limb 4,323 26.64 %
witness 3,208 19.77 %

TOTAL 16,227 100,00 %

Here is the graph for the starting values (in Volts).

http://www.somasimple.com/images/totalbegin.gif

The curve must say something to our experts in statistics?
It is the greatest study about TENS ever realized.8)

Diane and Nari, you'll be certainly happy with some of the conclusions! :wink:

[Diane]

Bernard, could you spell out your conclusions? I don't really get the graph, so I think I'm missing your big point.
Diane

[Alain]

Bernard:
If I understand the study's construct well: you are in fact measuring a (rather large, I must admit) population's sensation, not whether TENS is effective.
And so you found that the distribution of a population's sensation - or perception of a 60 Hz sinusoidal current - is Gaussian.
I would contend that this may depends on many variables including electrode placement, skin impedance, temperature, etc. In that sense, it may not be that surprizing that we are in the presence of a bell shaped curve.
Please tell us how this relates to pain control.
Thanks!
Alain

[bernard]

Here are the graphs, at the end values

http://www.somasimple.com/images/totalfin.gif

and the 2 curves (begin/end) on the same graph

http://www.somasimple.com/images/totalponderation01.gif

There is effectively a shift to the right.
So we would conclude that TENS had an effect over sensitivity and pain?

Do you noted the spikes on these curves?

more to come...

[bernard]

Here some more graphs;
1/ evolution within the number of sessions
http://www.somasimple.com/images/evolbeginend.gif

2/ evolution of groups/areas (begin/end)
http://www.somasimple.com/images/debutfingraf.gif

membre supérieur = upper limb
membre inférieur = lower limb
ensemble = total group (with witness)
témoin = witness group

Have you already some conclusions?

[bernard]

Some numbers!

refractory (0 %) 11.55 %
Low accommodation (< 30 %) 27.20 %
Normal accommodation (> 30 %. < 80 %) 39.47 %
high accommodation (> 80 %) 21.78 %

refractory (0 %) 11.55 %
Low accommodation (< 30 %) 27.20 %
Normal accommodation (> 30 %. < 80 %) 39.47 %
high accommodation (> 80 %) 21.78 %

area begin session End session Difference %
rachis 21.61 28.59 6.98 32.30
Inferior limb 18.52 24.92 6.40 34.56
Superior limb 27.02 37.47 10.45 38.67
Total 22.45 32.40 9.95 44.32
Witness 21.13 41.06 19.93 94.32

[bernard]

Conclusions:

1/ TENS brings an accommodation.
2/ this accommodation exists in patients and witness group.
3/ this accommodation carries an elevation of skin sensitivity in all group.
4/ TENS conditions body to suffer electricity and perhaps people to suffer of a better manner their pain?
5/ this conditioning is less efficient on painful patients.