tag:blogger.com,1999:blog-6193043695356712843.post2051418161334646392..comments2023-09-02T23:55:45.583+10:00Comments on Doctor Skeptic: Is back fusion surgery just a placebo?Dr Skeptichttp://www.blogger.com/profile/09376469049519802493noreply@blogger.comBlogger41125tag:blogger.com,1999:blog-6193043695356712843.post-35185528397921276852016-06-13T19:54:02.283+10:002016-06-13T19:54:02.283+10:00Nice blog..Nice blog..Edwardhttps://halairportroad.manipalhospitals.com/speciality.phpnoreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-10070821136396827852016-03-20T17:31:57.554+11:002016-03-20T17:31:57.554+11:00I certainly use percentages in my discussions with...I certainly use percentages in my discussions with patients, when they are known. However, there is a need for patients to be better informed of risks and benefits, which is why many groups are working on more detailed "decision tools" for certain procedures. A Cochrane review has shown that for some conditions, patients are less likely to choose surgery when better informed.Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-86627020893544483342016-03-20T03:12:33.359+11:002016-03-20T03:12:33.359+11:00Patients understand biologic plausibility- there i...Patients understand biologic plausibility- there is a narrowing, the nerve is pinched- not complex statistical outcomes- randomized controlled trials with ordinal data Oswestry Low Back Pain Disability Questionnaire and pain scale outcomes. Statistical vs clinically significant effects, numbers needed to treat vs numbers needed to harm, p values, etc. I know of no surgeon who obtains informed consent using anything other than biologic plausibility while mentioning possible complications to include bleeding, infection, need for more surgery, nerve damage, etc. (the probability of these complications is not mentioned) Is your experience different? Informed consent is not really informed. At the end the patient often says doctor if the surgery will help lets do it, or do what you think is best, or if I was your mother would you do it (this last one is slightly more sophisticated.) Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-51648302874649150502016-03-02T07:23:00.494+11:002016-03-02T07:23:00.494+11:00Trillion dollars lost in total healthcare waste, n...Trillion dollars lost in total healthcare waste, not just spine- that would just be in the billions.Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-90001480219930744712016-02-27T07:44:29.668+11:002016-02-27T07:44:29.668+11:00It would be preaching to the choir! Perhaps we cou...It would be preaching to the choir! Perhaps we could get our government leaders to read it. I would say the public but marshalling the public is a fool's errand. It may well be that around a trillion dollars or more are lost every year in the US alone. This is a truly staggering cost.Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-35504734898897847022016-02-24T09:34:36.589+11:002016-02-24T09:34:36.589+11:00If you like the blog, you will love the book: http...If you like the blog, you will love the book: https://www.newsouthbooks.com.au/books/surgery-ultimate-placebo/#buy (or try Amazon)Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-35993386240008913642016-02-24T07:45:46.221+11:002016-02-24T07:45:46.221+11:00Thanks for the excellent posts Dr Skeptic. These p...Thanks for the excellent posts Dr Skeptic. These posts are more valuable and informative than much of what I learned in medical school. Correct reasoning and observation are critical to knowing what truth is. I too believe spine surgery is largely a placebo. Reasons- Many spine findings are asymptomatic, disk osteophyte complex, neuroforamenal narrowing, spinal stenosis, degenerative disk disease. Biologic plausibility reigns supreme in spine care which is faulty logic- surgery corrects a deformity and alleviates pain (sounds reasonable but isn't true), many patients do not get better with surgery. There is no convincing evidence that surgery works- where sham surgeries and RCTs have been done no significant benefit is seen. Much lower quality evidence rests on ordinal data from patient surveys. The surgical group has a lower Owestry score or pain score. This means little if anything. Many patients in both surgery and non surgery groups still have pain. <br />Another issue is risks versus benefits With time the harmful effects of surgery come to pass negating any so called benefit of surgery- I see many complications from implants including irritable fixation, infection, accelerated disease above and below the operated segment. The so called benefits if they are real decrease with time and pain scores tend to equalize between surgery and "conservatively treated" groups after a few years. Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-49307925024884477812016-02-20T13:01:03.376+11:002016-02-20T13:01:03.376+11:00Yet the analysis depends on a normal distribution,...Yet the analysis depends on a normal distribution, not on whether or not you think it is normal. You could argue that nothing is "normal" - that the difference between an age of 1 year and 2 is not the same as the difference between 91 and 92. And from my understanding, with enough numbers, parametric tests will be reliable.<br /><br />However, you are correct in that non-parametric tests should be used when you are in doubt and that they will inherently provide a more conservative estimate of statistical significance.<br /><br />But this is all predicated on the assumption that statistical significance (the p value) is important, which is arguable. If the study is of good quality (low risk of bias), it is the result of the study (the effect estimate, whether it be a mean, median, or proportion of patients getting x% better) that counts. If it is big enough for you to sit up and take (clinical) notice and is very unlikely to have occurred by chance (if the p value is less than 0.001, then knowing that it is 0.002 on a non-parametric test is not important) and if it is repeated in a separate experiment, then it is likely to be real.<br /><br />You might be less enamoured with p values and statistical testing of research findings if you view the Dance of the P Values: https://www.google.com.au/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=dance%20of%20the%20p%20values Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-16122438219189130812016-02-20T06:10:36.235+11:002016-02-20T06:10:36.235+11:00Thank you for reponding to my question. "With...Thank you for reponding to my question. "With scores on large scales, they can be treated as contintuous (interval) for statistical purposes, and tested for normality." Do you have evidence for this claim? I realize many ordinal scales are out there and have been demonstrated to correlate with each other and have fair reproducibility. <br /><br />Ordinal variables are obviously not normal. There's no point in testing what you know for certain a priori -- your data are not normal.<br /><br />the intervals between adjacent categories in an ordinal variable are arbitrary. It's not really meaningful to test for normality, since it depends on imposing an arbitrary scale choice.Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-71861148843291581562016-02-19T08:52:40.786+11:002016-02-19T08:52:40.786+11:00Owestry Questionnaire- 10 items: pain intensity, p...Owestry Questionnaire- 10 items: pain intensity, personal care, lifting, walking, sitting, standing, sleeping, sex (if applicable), social, and travel. Each item consists of six statements correlating to scores of 0 through 5, with the patient choosing the statement that matches his or her ability. The statement correlating with a score of 0 indicates the least disability, and the statement correlating to 5 represents the greatest disability.<br /><br />Scores are calculated as follows: [total score/(5 x number of questions answered)] x 100%, falling within a range of 0 through 50<br /><br />Pain, sex, and disability are not additive. It is an ordinal scale and comparing means between non surgical and surgical groups should not be done.Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-92176593121001558932016-02-19T08:34:02.370+11:002016-02-19T08:34:02.370+11:00Great article. Sounds like 10-15 for Owestry. 15 w...Great article. Sounds like 10-15 for Owestry. 15 would make many spine intervention outcomes not clinically significant.Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-65288224878924091922016-02-19T08:23:40.920+11:002016-02-19T08:23:40.920+11:00I meant the "term statistical significance.&q...I meant the "term statistical significance." typo. Sorry. Some of the research you quoted above calculated a mean. Means should not be calculated for ordinal data because the differences between a 4 and a 5 are not the same as the differences between a 10 and 11. From my reading a non parametric test should be used. Parametric testing may overstate outcomes. Do you agree?Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-53268429243713082152016-02-11T22:06:06.309+11:002016-02-11T22:06:06.309+11:00Depends what you want to use it for. There are man...Depends what you want to use it for. There are many studies on this. One reference is here: http://www.rehabmeasures.org/Lists/RehabMeasures/DispForm.aspx?ID=1114 Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-62530461239290184902016-02-11T22:03:11.663+11:002016-02-11T22:03:11.663+11:00Not sure what you mean by "stern statistical ...Not sure what you mean by "stern statistical improvement". Also, ordinal data is not qualitative, it is quantitative. Even dichotomous outcomes (2 ordinal values) is quantitative. <br />With scores on large scales, they can be treated as contintuous for statistical purposes, and tested for normality. If you don't like the idea of doing this, for several reasons, then like many, you can group them into excellent, good, fair and poor, or even satisfactory and unsatisfactory. But the bottom line is that these scores have been validated as being sensitive to change and reflective of the underlying phenomena that they aim to quantify.Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-38232565814332140772016-02-11T14:35:59.879+11:002016-02-11T14:35:59.879+11:00What is the MCID (minimum clinically important dif...What is the MCID (minimum clinically important difference) for Owestry and is it valid? I have heard 15.Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-4242973906580254202016-02-11T12:56:06.794+11:002016-02-11T12:56:06.794+11:00I have a question on spine surgery outcome measure...I have a question on spine surgery outcome measurement<br /><br />Oswestry Low Back Pain Disability Questionnaire<br />Beck Depression Inventory (BDI)<br />Medical Outcomes Survey 36-Item Short-Form Health Survery (SF-36)<br />McGill Pain Questionnaire<br />Roland and Morris Disability Questionnaire<br /><br />These forms provide ordinal data (qualitative)<br />In statistics, ordinal data is a statistical data type consisting of numerical scores that exist on an ordinal scale, i.e. an arbitrary numerical scale where the exact numerical quantity of a particular value has no significance beyond its ability to establish a ranking over a set of data points.<br /><br />How can the stern statistically significant improvement be used?Anonymoushttps://www.blogger.com/profile/12796245218427012668noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-77183613706953246482013-09-20T12:54:01.809+10:002013-09-20T12:54:01.809+10:00Ah, the "credible source"! So glad you b...Ah, the "credible source"! So glad you brought it up. I have been asked about the reasons for my anonymity several times and taken some criticism for it. The reasons are manifold and include separation of my clinical practice, being able to unify my message with my name, and avoiding crazy people. But one of the biggest reasons is because I feel the evidence should speak for itself, and not rely on the eminence of the provider. I have many letters after my name, but there are people out there who know more, and understand the science better than me, but are without any letters after their name. <br /><br />Basically, I didn't want people to take my comments as true, based on who I am.<br /><br />Having said that, I have several people out there is cyberspace with whom I converse privately. If you send me a comment that includes your email, I will respond directly to you without publishing it and we can discuss this further.Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-29304274729960503292013-09-20T10:55:09.530+10:002013-09-20T10:55:09.530+10:00Doctor Sceptic what is your email? I am trying to ...Doctor Sceptic what is your email? I am trying to use your sources for my paper on placebo surgeries and the ethics behind it yet I cannot find you as a credible source not knowing your degrees and such! Thank you!Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-19320853403321967312013-09-13T23:06:50.534+10:002013-09-13T23:06:50.534+10:00Agreed re spinal surgery. Most chronic back pain...Agreed re spinal surgery. Most chronic back pain has psychosocial cause. The sad thing, is when this IS recognized the sufferer has virtually no place to turn for help, as emotional cause for pain and CNS upset in other organs is not generally accepted by the modern medical establishment. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-50603699389215374142013-07-22T23:01:11.804+10:002013-07-22T23:01:11.804+10:00Thanks Mia,
Beliefs are hard to dispel. We are har...Thanks Mia,<br />Beliefs are hard to dispel. We are hard-wired by evolution to perceive associations that may not exist and to jump to conclusions. Being objective and recognising the biases that distort our understanding are hard work, because they are not natural to us.<br />I believe that science gradually guides practice in the right direction. There are many procedures that are no longer performed due to lack of effectiveness, that were thought to be effective at the time. Usually, however, that process takes a very long time.Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-30964559698914091342013-07-22T20:49:53.856+10:002013-07-22T20:49:53.856+10:00Yes, but the question should be: why in the face o...Yes, but the question should be: why in the face of evidence (lack of effectiveness) the 'belief' remains, for a very invasive procedure? Why is dogma in medicine so difficult to challenge?! Why science-based medicine fails to live up to its promise of being science-based?Miahttps://www.blogger.com/profile/11822325098959478693noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-30674861769486909312013-01-23T13:51:17.493+11:002013-01-23T13:51:17.493+11:00Thanks Ken,
Your condition, spondylolisthesis, is...Thanks Ken,<br /><br />Your condition, spondylolisthesis, is not included in any of the reviews or studies that I have mentioned. It is generally accepted as an indication for fusion surgery, although there is certainly some fuzziness around the edges when it comes to definitions of mild cases of spondylolisthesis. For example, common degenerative changes in the back are also associated with some degree of spondylolisthesis and this is often used as an excuse for surgery.<br /><br />There are cases out there where spine fusion is indicated. However, it is not indicated for back pain associated with degenerative changes, and it is not indicated for most spine fractures. Yet these are the indications used for most of the spine fusion surgery being performed today. Overall, it is a risky and expensive procedure that is being massively oversold.Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-46697804210290968142013-01-23T01:56:30.481+11:002013-01-23T01:56:30.481+11:00Hmm, very interesting. I am 43 and just underwent...Hmm, very interesting. I am 43 and just underwent L5-S1 spinal fusion due to a Grade III Spondylolisthesis and the MRI showed moderate to severe foraminal stenosis and a moderate to severe degraded disc between L5-S1. I had been born with spina bifida and the facet joints on the L5 were malformed and broken. I had no issues and was even unaware of it until I began experiencing pain about 9 months ago. I tried physical therapy for a couple of months since I am not a big fan of surgery, but nothing stopped the lower-back pain I experienced when sitting down, which negatively impacted my ability to drive even short distances.<br /><br />So after speaking with an orthopedic/neurosurgeon and doing lots of research I determined that there was nothing to stop the L5 from continuing to slip forward or stop the disc below the L5 from continuing to degrade. Therefore I would continue to experience the current pain with the possibility of some future pain as well due to the continued degradation of the disc and slippage of the L5. So I opted for surgery sooner rather than later since I could choose my doctor, hospital and days off from work. I could have waited, but there was the possibility that some major damage could occur (like Cauda equina or conus medullaris syndrome). But why wait until that happens, which may cause more permanent damage to the nerves?<br /><br />It has been 5 weeks since surgery and I feel almost normal. I am back to my regular exercise routines (stationary bike, elliptical rider, planks, push-ups, crunches, and long walks) but without bending, twisting, or lifting heavy weights until the fusion is well underway. <br /><br />But after reading your post I get the impression that you think it is "placebo". Of course I don't think so, but how do you prove to someone who takes the position that a cure is all in the patients mind?Kenhttps://www.blogger.com/profile/00255185033354145957noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-736090500869946912012-12-19T06:40:28.630+11:002012-12-19T06:40:28.630+11:00For my own personal benefit, send the link to your...For my own personal benefit, send the link to your friends.<br /><br />For the benefit of future patients my advice is the same as with other areas of medicine: maintain a skeptical eye. Do not assume that something is helpful, just because it is new, sounds scientific, or has been recommended by a professional. Understand that the benefits-to-risk ratio of many medical interventions is overestimated by doctors themselves, and that this overestimation is magnified down the line so that by the time we get to popular media, there is little correlation with reality.Dr Skeptichttps://www.blogger.com/profile/09376469049519802493noreply@blogger.comtag:blogger.com,1999:blog-6193043695356712843.post-47844432918510338412012-12-19T06:09:58.764+11:002012-12-19T06:09:58.764+11:00Excellent piece and discussion. How do we get thi...Excellent piece and discussion. How do we get this information into the wider culture?<br /><br />ANdyANdyhttps://www.blogger.com/profile/17296927896060072316noreply@blogger.com