OK, I'll add my own two pence!
Had an accident in 1967 which broke a disc into 2 parts very down low in my back. The parts EVENTUALLY knitted together again (with assistance from a LOT of plaster and a bloody great "stretch you out again" corset affair with weights on it, keeping me flat on my back for nearly 3 months. That problem was eventually "cured" - you could say by "mechanical intervention",plus the natural propensity for broken bones to grow back together again.
BUT, as well as the actual damage to the disc, there are other "side effects" - no. 1 being the likelihood that at least some adjacent nerves get damaged (happened to me); and no. 2, the fact that whenever we have pain the surrounding muscles try to compensate by "pulling" your body into a position to at least reduce the pain. That can cause the muscles to go into spasm, and can (did in my case) create a "weakness, whereby, for example the muscles in my neck and shoulders would go into spasm again if I happened to throw a bit of "excessive" force on those muscles during "normal daily life".
I'm NOT medically trained in any way, but as the above has been an on-going problem since 1967, I have had a certain amount of exposure(!!!) to all facets of the medical osteo profession, AND their "unqualified quack supernumeries"!
My own experience is clear in that to me anyway, no amount of chiropractor of physiotherapy manipulation is going to cure the original broken bone problem. BUT manipulating the above muscles problem? Yup, that has worked for me over the years, and TO A CERTAIN EXTENT, continues to do so. And that's basically for the "muscle spasm" problems. And that's BOTH by Chiros and Physios.
I found the best "trick" is to find someone who manipulates you in such a way that your own pain is relieved. "ALL BACK PROBLEMS ARE THE SAME AND ALL BACK PROBLEMS ARE COMPLETELY DIFFERENT" is what a back surgeon once said to me.
But like the broken bone problem, physical manipulation will NOT bring dead nerves back to life, BUT, and again TO A CERTAIN EXTENT, a "half dead" nerve CAN be brought back into some function to a limited degree, provided it hasn't been "allowed" to deaden completely (you can tell I'm not medically trained from my simplistic terminology, can't you)?
But I do now have polyneuropathy which means, in my case, I have reduced feeling in the soles of my feet, which in turn means my natural sense of balance is severely limited - if I look up into the sky and loose the natural horizon I tend to fall over! Physio has helped that problem a bit.
So in a nutshell, if you find a Chiro whose work helps you, great. If you find one whose work doesn't, look for another - OR look for a fully professionally-trained Physio (which, since I ONLY use hospitals, and NOT the modern chromium-plated lifestyle fruit juice gym palaces), means all the Phyios I've had have not only been professionally trained (3 years) + also undergoing regular update & refresher training.
So based on my own extensive experience, please do NOT ignore all Chiros (or Physios) just because you may have had an experience that didn't work for you, or have heard such from someone else - word of mouth can be your friend here, and there's enough back problems of all sorts around that you won't find it difficult to get a range of opinions about specific therapists and therapies, BUT you must sort the wheat from the chaff -just like reading blokes wittering on on t'internet really!.
In short, IMO you can forget "scientific proof - like many other professions, it seems to me that the medical profession is by no means short of the "NIH Syndrome" ("Not Invented Here"). It's "The Curate's Egg" and all that.
But because my own experience is that clear it is indeed possible for "phantom, psycho-sematic" pains to appear (usually because one particular set of muscles have been in spasm for too long), so please do NOT assume that all back aches are attributable to that problem.
I can assure you that it ain't so, and though I am loath to admit it here, there have been several occasions (not too many over the years thank Gawd) where I've been rolled up in a ball on the floor crying my eyes out, unable to breathe properly. NOT much fun!
Since that first plaster + corset "operation" I've has 2 further ops ("proper anaesthetic-types"), the last was in Dec '14. So to those who've had a "magical permanent cure" by whatever means, I'd have to say PLEASE BE CAREFUL: The chances are that you now have some in-built "weakness" and you need to take more than normal care in your normal daily life - bend your knees (a lot) when lifting, don't over-reach, don't over-stretch, etc, etc.
I well remember being in the Physio pool with the Physiotherapist (VERY NICE bathing suit!) at the Rehab centre after my 3rd back op, and through the big windows we could see the blokes working on a new extension to the centre. "Look at that bloke there" she said, "If he carries on like that he's going to have back problems in later years", and sure enough, he wasn't lifting in "the proper way".
I know a lot of members here do work on building sites and do a lot of other "physical work", and based on my own experience when I was servicing aeroplanes, we do, all of us, make moves sometimes that will create new problems or bring back old problems. So please take it easy.
Right now I'm sitting here (with difficulty) wearing a 3-point corset which immobilises my spine from just above the waist to just below the neck. The reason is that I've got another disc broken into 2 parts (not the same one as the original 1967 one). I had no accident, fall, etc, to bring this about, but now know I have osteoporosis - I was surprised to learn that this porosity of the bones isn't something that affects just females, men get it too, and it comes mainly from ageing (I'm 74). Another nasty that can creep up on you without you realising.
The two parts of the disc will re-join, but I must wear the thing 24/7 (except when showering!), can't drive, can't walk longer than about 15 mins, can't stand longer than than about 15/20 mins, etc, etc. I've had the "thing" on since early Oct and the quacks say it stays until early Jan, provided the next MRI and X-rays show all clear. But throughout it all I MUST do (special, reduced-type) Physio twice a week to make sure no further nerve damage occurs
I'm not looking for sympathy here, and repeat that all back problems are definitely distinct to each person, but having acted like a lunatic in my own physical work back in my 20s it's, clear that if most of us aren't always thinking about what we're doing physically. That way you definitely can be storing up problems for the future - as above, "DAMHIKT"!.
But at least medicine has moved on since 1967, and although my present corset is far from being funny, it's MILES better than the plaster & corset rig up I experienced back then.
Blimey, what a rant! Sorry all, but I hope there's something in all the above that may help someone (BTW, the above took 2 separate sessions sitting at the keyboard - went out for a *** break in the middle).