Only just seen this. Very interesting.
As someone who had a fall accident back in 1966 and hassuffered with back and related probs ever since, including ops on my back in 1969, 2002, and last - hopefully! - in 2014, you sunnybob, and all other similarly affected posters have my sincere sympathy. It ain't funny is it?
I first came across TENS during Rehab after my 2014 back op. The Physio in the clinic tried it (along with lots of other exercises & stuff) and TENS certainly helped me there. The Clinic machine was a pretty big trolley thing with lots of pads etc, but based on that, and the Physio's advice, I bought a little "tiny" box, battery powered, but with only 2 pads. (Sorry bob, I've never seen one with more than 2 pads, apart from the big trolley thing in the Clinic).
Mine is made by an apparently well-regarded company in the medical electronics field called Omron. They're Japanese, but have outfits all over the world, both manufacturing and distributing.
I bought mine from the local chemist and it cost the equivalent of about 65 quid (like just about everything else in Switzerland, that's expensive, and I'm sure it would be cheaper in UK - but not sure about Cyprus sunnybob).
As said, it has only 2 pads, and although these are replaceable, so far it's not been necessary - as per the hand book, when they start to loose their sticky you disconnect them from their leads (very good "press stud type" connectors), run the pads under a lukewarm tap for a few mo, then hang them up to dry - so far, they're always as good as new again half an hour later.
I was surprised at some of the posts about usage here, particularly the all-day treatment. The Omron book says you're only supposed to use my thing for 15 minutes at a time, max 2 or 3 times a day, min of 30 mins between each dose. In fact "the box" has a timer limit on it and after 15 mins it just stops and won't go any more for a while (presumably until 30 mins have elapsed). And that too is how the Clinic used their big trolley thing on me.
Mine is very easy to use, and has about a dozen or so different "programmes" with a little screen showing the area of the body to be treated - ranges from ankles, calves, thighs, backside, back, arms upper & lower, neck/shoulders, and hands (about 3 different hand areas).
Simple in use, there's a single "MODE" button and you just step through the modes until you see the picture on the screen of the body area you want to treat. The only other controls are an ON button (no OFF, as above it's auto shut off) and an intensity button, with settings ranging from 1 to 15. On me, I hardly feel a thing at setting 1 or 2, it normally starts to "tickle a bit" at 3 and I've never used it at above level 12 - beyond that it HURTS! Though I understand that depends on the intensity of the pain from the muscle spasms at the time.
As said, 15 minute time limit per treatment, and I use it "fairly often", sometimes twice a day, perhaps two or three times a month as a very rough average. So far it's never faltered and it's still on the supplied battery (dry cell, not rechargeable).
It helps me a lot, but as a previous poster has already said, in my case anyway, TENS alone will not do the job for me.
I take pills daily (prescription, regularly Dr. monitored), do daily exercises at home, and Physio-supervised exercises at the local hospital gym twice a week.
As someone who undoubtedly expended much more energy trying to avoid all sorts of "sports" while a schoolboy, and then during training in the RAF ("sports-mad buffoons"!) than I would have spent by just doing the "games" (yuck), I must say I'm now sold on the regular specific exercises at home and with the Physio - for me it's a simple decision really - do the exercising and I get less back pain, don't do them and the back ache increases in severity and regularity - despite the pills and TENS.
About the only advantage to the higher cost of buying my little box over the counter from a chemist in Switzerland (compared to on line was the fact that I bought it but was allowed a 100% money back guarantee if I was dissatisfied within 30 days. But I needed a Dr's "paper" to get that deal).
I should stress I'm in no way medically qualified and all the above is simply my own experience.
And Oh Yes sunnybob, you're dead right, just about all the Physios I've met are little tiny slips of girls who look like they'd blow away in the first strong wind, but blimey, they don't 'arf put you through it!
And yeah, in my case anyway, it doesn't pay to get too much "engaged" in anything - working in the shop, reading, on the PC or whatever - after about an hour, if you've been standing and/or bending, then change to sitting - or vice-versa of course. Bloody nuisance when you're in the middle of something, but it does help!
"Gute Besserung an Alle"!