|
|
Re: Look at this validation study guys, worth reading!
|
Logged in as: Guest
|
|
Users viewing this topic:
none
|
|
Login  | |
|
Re: Look at this validation study guys, worth reading! - January 9, 2005 10:39:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Jon:
You raise some interesting questions in regard to the assumptions for multiple regression. Let me start by saying that we did not perform any regression analyses in the validation study that was just published. I think you may be confusing what was done in the original development study published in Spine, where regression was the primary analysis to develop the rule? In the development study, most of the traditional assumptions were in fact met, although there is never ample space within a journal publication to specifically address each of these individually. The requirement for high levels of reliability for entry into a multivariate regression model is more debatable. There is not enough time to get into the nuisansces here, but suffuce it to say that when you combine the results of individual tests (as was done in the prediction rule), not every single test has to be highly reliable to still have validity. In other words, the commonly taught presumption that reliability is a precursor to validity, although generally an accurate statement, is not always the case. For example, assessment of lumbar spine stiffness is not the most reliable test, it still had enough predictive power to be retained in the final regression model (again tallking about the original development study). I would refer you to an editorial that Rob Wainner published in JOSPT in for a more detailed discussion if you're interested. Here is the citation. Good question though.
John
Reliability of the clinical examination: how close is "close enough"? J Orthop Sports Phys Ther. 2003 Sep;33(9):488-91. PMID: 14524507
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 9, 2005 3:06:00 PM
|
|
|
Barrett
Posts: 967
Joined: July 28, 1999
From: Cuyahoga Falls, Ohio
Status: offline
|
John,
If I had suggested at any point that manipulation should never be used your reply would have been expected and sensible. As it is, that old saw about aspirin doesn’t actually fit here as far as I can see. We’re talking about movement and not chemistry. The use of aspirin is something that can be precisely controlled and any deleterious effects are dissipated rapidly for the most part. This is not necessarily the case with manipulation and disregarding the consequences of that continues to make me wonder about such enthusiasm for this practice, whatever might be proven about its effect.
As Waddell makes clear, the emphasis on tissue that we’re capable of imaging has revealed very little and gotten us nowhere. Instead of trying to change the same tissue with coercion why not consider the neuromodulating effect movement might have? This can be done with movement that is safer and far easier to control.
Saying that not choosing to manipulate our patients is the same as providing suboptimal care is a mistake, and I take exception to this.
_____________________________
Barrett L. Dorko P.T.
http://barrettdorko.com
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 9, 2005 3:54:00 PM
|
|
|
Jon Newman
Posts: 1697
Joined: April 24, 2004
From: Amherst, WI
Status: offline
|
Hi John,
Thanks for addressing my statistics questions. Although they really aren't the interesting questions I have. Those remain unanswered.
jon
_____________________________
[URL=http://www.sonymusic.com/clips/selection/30/064887/064887_03_03_30.wav]Evidence[/URL]
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 9, 2005 7:30:00 PM
|
|
|
steve
Posts: 468
Joined: May 14, 2003
From: Canada
Status: offline
|
Hi John,
First of all, thank you for taking the time to respond to questions and doing a research study that is very clinically applicable. I think it is a big step in helping a clinician determine when to use a given intervention.
My question is why a non specific long lever manipulation technique was used as opposed to a short lever technique? My guess would be that you wanted to standardize the treatment intervention - although I would suggest that based on the fact that you used the finding of a hypomobile segment as a predictor of success, you could have also manipulated that specific level. Some schools of thought would think that a non specific long lever technique would have the potential to injure a hypermobile segment. Based on your results this would not seem to be the case but perhaps a specific technique would be even more efficacious? Interested to hear your thoughts,
Steve
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 12:29:00 AM
|
|
|
SJBird55
Posts: 2363
Joined: May 10, 2004
From: Michigan
Status: offline
|
Barrett, I probably shouldn't talk for John, but you are generalizing his statement a bit, aren't you? I would interpret John's statement and study to instead mean that in patients in that time frame of injury that fit the clinical prediction rule for the lumbar spine then manipulation is an excellent choice with published outcomes. What other options do you propose that have been published in peer-reviewed literature that would indicate a better option for patients in the defined scenario?
And Barrett, do you truly believe that manipulating the lumbar spine has substantial risk? What are the consequences of manipulating the lumbar spine? Forgive me for my ignorance, but in regard to the lumbar spine, I'm not aware of any risks. I am for the cervical spine, but I need to be enlightened with the lumbar risks/consequences.
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 6:30:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Barrett:
The bottom line is that risks of serious complications from lumbar spine manipulation are extremely small, almost small enough that we shouldn't even be talking about them. The cervical spine is a different issue, although the risks are extremely low there as well. There is a much greater chance that the patient you put on the treadmill to walk will experience a sudden MI that results in death than there is experiencing a cauda equina syndrome from lumbar spine manipulation.
If you can show me with data from a high quality clinical trial that your alternative can generate this magnitude of change for this subgroup of patients, I would be the first to use it in my practice. Until then, I re-iterate that not providing manipulation for these patients is synonymous with suboptimal care. We have a secondary analysis from the larger trial demonstrating that the risks of experiencing a worsening in status (not a serious complication, just clinical worsening) are much greater when you elect not to manipulate these patients. In other words, given the extremely low risks of manipulation, we should be talking about the risks of not doing it rather than the risks of doing it. If you are hearing me say that every patient with back pain needs to be manipulated, that couldn't be further from the truth. The issue is about matching treatment (or non-treatment) to the subgroup of patients most likely to benefit a particular patient.
John
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 6:31:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Jon:
I would be curious to know your remaining "interesting" questions.
John
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 6:48:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Steve:
Your question about how we selected the specific technique is a good one. The main reason was that previous studies assessing the benefits of manipulation incorporated this technique, primarily from Tony Delitto's and Dick Erhard's earlier research in the classification system. Thus, it had some baseline level of evidence to suggest it might be helpful. The other rationale is that the technique is not difficult to perform (nor are most other techniques). Manipulation is just a motor skill that requires practice. Our profession has made it out to be "rocket science", promulgating false notions about its risks. This has only resulted in lower than expected utilization rates and a fear of providing optimal care. Unfortunately, much of the blames for these misperceptions eminate from the continuing education circuit, which stands to benefit from the perception that it's technically hard and dangerous. It also contributes to this notion that folks who can manipulate are the "elite". This is utter nonsense (see the paper we just published in JOSPT related to experience).
With regard to the short- vs. long-lever technique and the issue of specificity, my sense is that most manipulative techniques are general anyways. Besides, I'm not sure being able to maniulate a specific segment matters anyways (presuming that it can be done, which is also doubtful). There is just no data to support the notion that manipulating a hypermobile segment (unless it's perhaps truly mechanically unstable as with a fracture) is harmful. Having said that, we have several ongoing studies to compare techniques though, and we should let the data have the final answer. My sense is that it's not so much which technique you're using, but just the fact you're manipulating them and getting things moving. This is heresy for many who have spents hundreds of dollars (myself included earlier in my career) learning so-called specific techniques for presumably an infinite number of biomechanical "dysfunctions", none of which can be identified reliably or have any data to support their validity. Enough for now.
John
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 10:56:00 AM
|
|
|
Bournephysio
Posts: 579
Joined: April 25, 2002
From: Calgary
Status: offline
|
John, Thanks for spending time to answer questions about your study on this forum. The use of a more general technique for lumbar and thoracic spines mirrors my clinical experience. I have simplified the manips I do. I usually do a bilateral gap for Tsp and either gap in flexion or extension for lumbar. I still try to get close to the correct level. I talked to McGill a couple of years ago. He was doing a study with chiropractors looking at how well they could localize a manip. They used multiple microphones to localize the pop. They were finding that they could not localize the manip. I have yet to see this study published.
I am wondering what technique you use for the neck. Though rare, VBIs are a major concern for cervical manips. I would imagine that a more general technique would involve large amounts of rotation and extension. While no proof exists, this is thought to a contributing factor to strokes. Erl Pettman strongly believes (last I chatted with him) that clinical instability of the neck is a major risk factor for strokes with manipulation. While there is no proof of this, it is a very logical hypothesis. I have not attempted to simplify my neck manips because of this. In addition I try and manip with the gliding of the joints and don't attempt to gap the joints as I believe that this could theoretically put more stress on the VA. What are your thoughts on this?
Barret, I am having problems following your arguments.
I don't think this study treats low back pain as an essential diagnosis. I think that it recongnizes that back pain can have different causes. Different causes are likely to respond differently to different treatments. Different causes are likely to have different signs and symptoms. We can't determine the different causes of low back pain but we can determine the signs and symptoms. Thus this study is able to bipass the different causes of low back pain.
I'm sure you believe that the basic science literature backs your method of treatment (and it may, though I don't see it) but how things work in "theory" and how they work in real life can be vastly different. We basically have to rely on your (or others) clinical experience. We have evidence that manipulation works, we still need evidence that your method works.
One of your arguments against manipulation is that it involves coercion. This seems like an emotional argument rather than an argument of any substance.
"Instead of trying to change the same tissue with coercion why not consider the neuromodulating effect movement might have?"
Manipulation is a movement with a neuromodulating effect. It is not trying to coerce the bone to move into the right position. In my experience, most of our treatments work by the same principle be it exercise, electrical modalities, PNF, M/E, manipulation or acupuncture. Some seem to be more powerful than others. I have more success with manipulation and acupuncture. Of course thats just my clinical opinion.
"There seems to be little concern for a theoretical approach that includes a tissue at fault in a certain way, and in a way that can be changed in the right direction with manipulation. Why have we abandoned this issue?" This issue has been abdondoned for a large part in low back research because we don't know the tissue at fault. There is still plenty of research looking into this.
If I have misinterpreted your arguments let me know.
Doug
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 4:27:00 PM
|
|
|
Jon Newman
Posts: 1697
Joined: April 24, 2004
From: Amherst, WI
Status: offline
|
Hello John,
You can read the thread from the beginning to glean the context of the questions I've asked. But for convenience, here's a list of questions I've generated thus far that have largely been unanswered.
This article validates that manipulation (1 specific technique) was more effective than aerobic exercise and choreographed lumbar ROM therex alone. Does it follow that the theory upon which spinal manipulation is taught is valid?
What do others think about the predictive factors as they pertain to the theoretical underpinnings of spinal manipulations?
What are all the factors that manipulation offers that the alternate treatment did not?
So, while the technique works, what is a better explanation for why than biomechanics flaws?
I understand that something that predicts does not necessarily explain. But shouldn't it be the case that variables that explain at least also predict?
Perhaps these questions are banal, but I don't think so. John, I think you largely answered my questions in addressing Steve: "My sense is that it's not so much which technique you're using, but just the fact you're manipulating them and getting things moving."
I'd like to hear everyone’s' answers to these questions. Why so quiet? I’ll compose some of my own thoughts regarding issues of construct validity and post them in a while.
jon
_____________________________
[URL=http://www.sonymusic.com/clips/selection/30/064887/064887_03_03_30.wav]Evidence[/URL]
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 4:59:00 PM
|
|
|
ericm
Posts: 171
Joined: March 13, 2003
From: Nanaimo, BC
Status: offline
|
John, is it reasonable to think that the patient group who received the exercise intervention without manipulation were possibly made worse through the exercise? Or if not worse, at least had the potential extent of their natural recovery impeded in some way. Thus magnifying the positive results in the manipulation group? (my apologies for not having read the study yet)
Eric
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 6:11:00 PM
|
|
|
Bournephysio
Posts: 579
Joined: April 25, 2002
From: Calgary
Status: offline
|
"This article validates that manipulation (1 specific technique) was more effective than aerobic exercise and choreographed lumbar ROM therex alone. Does it follow that the theory upon which spinal manipulation is taught is valid?"
No!
"So, while the technique works, what is a better explanation for why than biomechanics flaws?"
There has been a fair bit of work on that. I'd direct you to work of people like Wright, McGill and Herzog.
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 6:59:00 PM
|
|
|
steve
Posts: 468
Joined: May 14, 2003
From: Canada
Status: offline
|
Jon,
My question was asked for the same reasons yours was - I have been trained in a very biomechanical and anatomy driven model that I have become quite disillusioned with. There is some evidence that manipulation is an effective intervention. There is conflicting evidence about what the thoracic spine, lumbar spine and sacroiliac joint do biomechanically in a healthy individual and no evidence for those in a pathological state. Even if we understood the biomechanics fully, joint mobility testing is poor at best with pain provocation being slightly better.
So if this is the case why do individuals get better with manipulation even though the chances are that with specific techniques (Of a level research says we cant identify as being limited in mobility) our manipulations target multiple levels of joints that may or may not be affected, that may or may not be glided along there biomechanical planes? Possibly a cool placebo effect although there is enough research to say that there is some effect. My guess is that the reason manipulation (Either specific or general) works is that it floods the central nervous system with mechanoreceptor feedback and allows increased muscle tone in the larger muscle that work to protect the affected region to decrease and allow proper movement to occur. Having said that, I dont have any more evidence to back up my theory!
Irrespective of why it works, is anyone else wondering why alot of the schools of thought continue to teach these theoretical models that have a preponderance of evidence indicating that they are incorrect - Ie. we can palpate a specific lumbar segment, determine its lack of mobility, treat them with a specific level manipulation and with a biomechanically correct technique?
Steve
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 8:13:00 PM
|
|
|
Bournephysio
Posts: 579
Joined: April 25, 2002
From: Calgary
Status: offline
|
"My guess is that the reason manipulation (Either specific or general) works is that it floods the central nervous system with mechanoreceptor feedback and allows increased muscle tone in the larger muscle that work to protect the affected region to decrease and allow proper movement to occur."
This is really the only explanation that makes any sense (add in ascending/descending pain modulation). Although I would remove "larger" and proper movement may or may not be a requirement for pain relief. There is some evidence in support of a neurophysiological effect:
Wright has shown a neuromodulatory effect of mobilization of a distal joint on a proximal joint.
Herzog has shown reflex activity with manipulation
McGill has shown decrease emg response to pressure ofter manipulation.
Thats just off the top of my head.
According to Julls study, pain provacation is very valid for the neck. I would be suprised if motion testing of the neck wasn't fairly reliable. The study that is the subject of this thread shows that there is some validity to biomechanical testing so I wouldn't throw out the biomechanical testing just yet. It has been my experience that "stiff" joints on biomechanical testing do "loosen" after a manipulation even if the manipulation is not specific. It is my theory that we are just feeling increased muscle tone which is relaxed by the manipulation.
Doug
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 10, 2005 8:20:00 PM
|
|
|
steve
Posts: 468
Joined: May 14, 2003
From: Canada
Status: offline
|
I agree with you Doug on a number of points. The reason I didnt include the neck as an area for mobility testing is the Jull study. The muscle tone that we interpret as stiff joints fits nicely with the neurophysiological effects and your right - it does decrease post manip.
Steve
Steve
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 11, 2005 2:52:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Bournephysio:
Here are some papers demonstrating that manipulation in general is probably not as specific as we'd like to think. Again, the question becomes, even if we can be specific, does it matter? I must admit that I put effort into being specific, but I am not at all disillusioned into thinking that I'm actually doing so. The study by McGill you mention is cited below.
Beffa R, Mathews R. Does the adjustment cavitate the targeted joint? An investigation into the location of cavitation sounds. J Manipulative Physiol Ther. 2004 Feb;27(2):e2.
Ross JK, Bereznick DE, McGill SM. Determining cavitation location during lumbar and thoracic spinal manipulation: is spinal manipulation accurate and specific? Spine. 2004 Jul 1;29(13):1452-7.
In general, the evidence suggests that mobilization and exercise (again, the combination is important because the evidence suggests that manipulation alone is typically not the optimal treatment) for patients with neck pain is equally as effective as thrust techniques and exercise. Combined with an increased potential for risk (albeit still very small), it doesn't seem to make rational sense to frequently manipulate (ie, thrust) the neck. Manipulating the thoracic spine in patients with neck pain is a different story altogether. We have some data that will soon be publised in Manual Therapy demonstrating short-term benefits of thoracic manip in patients with neck pain. I think the in press version is uploaded on the website?
John
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 11, 2005 3:16:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Jon:
I have pasted your questions here and respond individually.
Question: This article validates that manipulation (1 specific technique) was more effective than aerobic exercise and choreographed lumbar ROM therex alone. Does it follow that the theory upon which spinal manipulation is taught is valid?
Answer: Not sure if you've read the article, but we didn't compare manipulation versus aerobic exercise and lumbar ROM exercise? We compared manipulation and a simple ROM exercise versus aerobic exercise and an exercise strengthening program (essentially lumbar stab). After the 1st week of treatment, patients in the manipulation group completed the same exercise program as patients in the exercise group, with no further manipulation being provided. The exercise strengthening program has considerable evidence for its effectiveness, making it a compelling comparison group.
Question: What do others think about the predictive factors as they pertain to the theoretical underpinnings of spinal manipulations?
I will let others answer here. The answers may be interesting, but we don't need to understand them to help lots of patients with back pain improve. We still have little information on why manipulation works. There is certainly emerging evidence that its probably some neuromuscular mechanism, but exactly what is occuring remains unclear. Again, useful questions for future research, but we don't have to understand all the answers before deciding that the evidence suggests we should at least manipulate a subgroup of patients with back pain.
Question: What are all the factors that manipulation offers that the alternate treatment did not?
Not sure what this question is asking. The biggest "factor" that manipulation offered the subgroup of patients positive on the rule that the alternate treatment did not was a huge improvement in pain and disability, the effects of which persisted at 6 months and were associated with decreased healthcare utilization.
Question: So, while the technique works, what is a better explanation for why than biomechanics flaws?
I have little idea other than the preliminary evidence to support some sort of a neuromuscular mechanism. That's about as specific as we can get. The one thing we do know with some degree of certainty is that we're not "moving bones" or correcting the infamous "subluxation". The data is clear about this.
Question: I understand that something that predicts does not necessarily explain. But shouldn't it be the case that variables that explain at least also predict?
The criteria in the rule are explaining outcome (ie, distingusing between patients with and without a successful outcome), not explaining a mechanism for why manipulation works. Not sure if this addresses your question?
Hope this helps.
John
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 11, 2005 3:20:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Eric:
Patients in the exercise group without manipulation also experienced clinically meaningful improvement over time on average, so there's little argument to suggest the exercise intervention generally made people worse. There were some folks who were positive on the rule randomized to receive exercise alone who experienced a worsening in status (defines as > 6 point worsening on the Oswestry). Again, these folks are not getting harmed per se, just an increase in disability. The data would suggest that this is because these patients were not manipulated, not because the exercise program inherently poses some degree of risk. Again, the evidence to support lumbar stabilization is considerable (and itself highly effective for another subgroup of patients, the results of which will be published in the near future). Hope this helps.
John
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 11, 2005 3:36:00 AM
|
|
|
childsjd
Posts: 63
Joined: June 29, 1998
Status: offline
|
Steve:
Your comments are on target so I will let them stand alone. Why do these schools of thoughts still persist? Part of the issue is simply ignorance (not intended in a demeaning way) in that folks don't stay current with the evidence and are reluctant to abandon their pet theories even when confronted with new evidence that stands in contrast to their belief system. If you have vested thousands of dollars understanding a particular theory, how easy is it to let go and admit you might have been better off flushing your money down the toilet? Therefore, there continues to be a market for educational courses that teach baseless theories with absolutely no evidence to support them (other than purely theoretical constructs). I repeatedly encourage these folks to prove it with clinical research. No one is ever interested in taking us up on the offer. hmmmm. Just my honest assessment.
The other issue is that these schools of thought stand to lose huge profits by letting go of their pet theories that require multiple courses and many hundred of dollars to become "proficient". You are instead dazzled about what an elite therapist you will be when you reach the "holy grail" status of having attended all their courses. If it's more simple, you need less training to become proficient at a few techniques that will help lots of patients. And so the cycle persists.
Not to be a commercial here, but that's exactly why we now actively teach courses grounded in evidence. Bridging the gap between the academic setting and the realities of clinical practice is essential. Although we would hope that everyone remains current in the evidence on their own, the realties are that folks look to continuing education to assimilate new information. The focus of our courses is introducing folks to the evidence, teaching a core set of techniques, practice them a lot in lab, and learn evidence-based decision-making strategies about when to use them. 10% of all profits are dontated back to the Foundation for Physical Therapy to further research because this is not about making lots of money. It's about translating evidence into practice. Enough of the commercial. If you're interested, you can get some information at [URL=http://www.evidenceinmotion.com.]www.evidenceinmotion.com.[/URL] Let me know if you have any questions. Eventually the idea is to increase fellowship opportunities for folks who are interested.
John
John
|
|
|
|
|
Re: Look at this validation study guys, worth reading! - January 11, 2005 8:52:00 AM
|
|
|
Diane
Posts: 1499
Joined: March 9, 2001
From: Vancouver, B.C., Canada
Status: offline
|
Hi John,
Thanks for coming on here to clarify your study. I'm a non-manipulator, and always will be, working I suppose from suboptimal (I guess..) theoretical constructs that have no evidence to support them, like pain theory and neuromatrix theory.. movement impairment syndrome theory.. all the soft tissue stuff..
I'm wondering, in your cognitive explorations of and efforts to pin down proper useage of manipulation, if you've come across any notions or anecdotes or studies that have to do with increased pain in people who became manipulation addicts at some point in life. It's probably not a concern or issue for anyone who hasn't yet attained middle age, but I'd like to speak up for an as yet unstudied (probably) segment of the population whose pain has become chronic or persistant, and find out if there's any data to put their pain together with having been manipulated/adjusted, popped or otherwise overtreated by manipulative practitioners who are perhaps not nearly as selective as you seem to be.
Regards,
Diane
|
|
|
|
 New Messages |
 No New Messages |
 Hot Topic w/ New Messages |
 Hot Topic w/o New Messages |
 Locked w/ New Messages |
 Locked w/o New Messages |
|
 Post New Thread
Reply to Message
Post New Poll
Submit Vote
Delete My Own Post
Delete My Own Thread
Rate Posts |
|
0.125
|
Printable Version
