These results suggest that factors aside from the instillation of PMMA may have accounted for the observed clinical improvement after vertebroplasty. Such factors may include the effect of local anesthesia, as well as nonspecific effects, such as expectations of pain relief (the so-called placebo effect), the natural history of the fracture, and regression toward the mean. The possible role of the placebo effect on outcomes in this trial remains unclear. Previous studies have documented pain reduction in placebo groups, on the order of 6 to 7 mm on a 100-mm scale. The treatment effect in our trial was substantially larger than those in previous studies, even though the previous studies included both pharmacologic and psychological interventions in addition to physical interventions.

1. Why was the pain relief in Buchbinder half of that in Kallmes (2/10 vs. 4/10 on average)?
2. There is a sense from the Kallmes trial (with the differences between groups in rates of guessing correctly which treatment they initially had and rates of seeking cross over) that real VP had some benefit over sham which wasn't noticable at all on pain and disability questionairres. Or pain 'really was' improved in the VP group compared to placebo and the study didn't have the power to show it. Even if that's the case it is not good news for VP - if the benefits (over sham) are so minimal (or rare) that you need more than 130 patients to demonstrate it - this is not a ringing endorsement of the procedure. Needing more than 130 patients to prove a treatment saves a few lives a year is fine (and typical in cardiovascular research); for an analgesic modality it means it's pretty worthless.
3. It is possible the sham procedure is actually an effective, active treatment for VCFs which they inadvertently demonstrated in these trials. It seems physiologically unlikely (outside of the initial hours after anesthetizing the pedicle) but one could invoke some 'placebo' response explanation? Such as - patients think this will help; anesthetizing the pedicle gives them rapid and effective pain relief; patients now 'know' if fact this will help and despite the fact that nothing else has been done which effectively relieves pain (including, apparently, the installation of cement into the vertebral body); this expectation/belief provides the patients durable (months long) pain relief.

1. Balloon kyphoplasty, a related procedure, was not investigated and one can't conclude anything about KP from these trials (despite the compelling** non-blinded controlled research I cited above). However, these papers indicate the effectiveness of KP can no longer be assumed without properly blinded studies.
2. It's possible that certain patients would receive benefit from VP over sham; patients with very acute fractures, specific anatomy, etc. (there has been for instance a clinical impression that more acute fractures respond better). Perhaps...but we can no longer assume that without it being demonstrated properly.
3. Who knows about cancer patients? All I can say, and to join most of the world here, VP frequently seems to help. And in fact it does help, even if it's placebo - see below.
   

1. These papers, if you accept their findings as they are (which I do - they are as good as you can get when it comes to this sort of symptom research), shouldn't actually lead us to conclude that VP is as good as medical/conservative management. VP is better than medical management, and has been shown to be so (as has KP). The results very specifically mean VP is no better than 'sham,' which is a different conclusion than no better than medical management. The difference is now we have reason to believe VP is better than medical management due to that thing called 'the placebo effect' as opposed to, eh, 'real analgesic effects' of instilling PMMA into a vertebral body. Real in quotes there because I don't mean to suggest that 'placebo' is not a real analgesic. It is, god knows, I just wish I had it in a bottle as opposed to a fancy fluoroscopy suite.
   
2. I have thought VP and KP are pretty darn good things the last few years as I've seen many patients feel a lot better afterwards. It's frustrating and you wonder what would have happened if rigorous, blinded studies were done early on. E.g. the technique is developed and a few case series suggest a powerful treatment response to VP (this in fact happened). Next, a properly blinded trial was done which showed no benefit. Maybe this was repeated with larger trials - still no benefit - VP is never adopted and never became as wide-spread and accepted as it has now become. Instead we had large, unblinded trials; VP still looks great, everyone loves it, and then this. All of this makes a good argument (if we ever needed one, which we do, as we constantly forget) for remaining skeptical of unblinded treatment trials and also of doing blinded trials early, particularly with novel therapy.
   
3. But coming back to #1 there, what do you do clinically given that it still remains that VP is 'superior' to medical management (at least in the short term) even if it's because of placebo. It's not ethical, supposedly, to prescribe placebos, right? But we do it all the time - at least I do with, for instance, lidocaine patches for pain syndromes highly unlikely to 'actually' respond to a lidocaine patch - I do it because it's almost ridiculously safe and a substantial minority of my patients report they feel a heck of a lot better. An invasive procedure is different though; while quite safe the tiny risk of a catastrophic adverse event remains. Frankly, for patients with disabling pain that I cannot effectively treat medically/conservatively without dose limiting side effects, I think I will continue to recommend this, or maybe kyphoplasty to make myself feel better.
4. Please comment as to what your plan to do based on these studies. I'm also curious to the community's larger response and if this will in fact be the death of VP. As long as people get reimbursed for it though I imagine it will continue to be practiced.
5. I Googled vertebroplasty to see if there were any open source images for this post and found this link (www.youhaverights.com/medical-devices/spinal-cement/) was at the top of my search (it was a paid link, and I am not embedding an actual link here because I don't want to improve this website's Google rank by doing so). Yes, people are already trying to cash in on this via litigation (thus this post's title). God bless America.