Click here to read well written blog by Alan Taylor who explores the evidence on stroke and manual therapy with respect to the sad case of Katie May who died at the age of 34 from a suspected neck injury.
Does cervical lordosis change after spinal manipulation for non-specific neck pain? A prospective cohort study
I’m pleased to report that our new paper exploring the mechanism of spinal manipulation has been published today. We wanted to investigate the theory that spinal manipulation for non-specific (so-called) neck pain might be associated with changing cervical lordosis. Read about the study here!
(Last year’s paper, in case you missed it, described our investigating of whether spinal manipulation for neck pain was associated with increased inter-vertebral motion, and whether any increases were related to patient-reported outcome measures. Click here to read that one).
I was delighted to attend and represent BU at The Society for Back Pain Research (SBPR) Annual General Meeting 5-6 November 2015 which was conveniently held in Bournemouth, at Anglo-European College of Chiropractic, a partner college of BU. SBPR was formed in 1971 to promote the study of all clinical and scientific aspects of spinal pain, including the neck (my area of interest), and to encourage research into its causes, treatment and prevention. There are now over 200 members of the Society, from a wide range of disciplines including all sorts of healthcare professionals and scientists. Suffice to say if there is anything about back pain this audience does not know it is probably not worth knowing! Having said that, attending this meeting reminded me just how much about back pain is still unknown…
Biological Factors in Non-Specific Back Pain
The title of this year’s meeting was ‘Biological Factors in Non-Specific Back Pain’ to place an emphasis on the ‘biological’. It has been over 25 years since the biopsychosocial model was applied to back pain but lately research has tended to be more concerned with psychosocial aspects, such as fear-avoidance behaviour or depression; research into physical findings to diagnose back pain has sadly not been very fruitful. [An important point was made by Professor Maurits van Tulder, that research has actually been largely focused on psychological factors, to the expense of social factors]. While psychosocial factors do seem to be important in influencing patients’ recovery, they don’t get us much closer to a diagnosis, to finding out what is producing and driving the patient’s pain.
In terms of disability-adjusted life years (DALYs) (the sum of years of life lost due to premature mortality and years lived with disability) from non-communicable disease, low back pain ranks #3 (after ischaemic heart disease and stroke) and neck pain # 14 in the top 25 leading diseases and injuries globally. In the United States low back pain is the number one cause of years lived with disability. If you are not involved in the field of musculoskeletal disorders as a researcher or clinician, it may surprise you to know that, despite the size of this problem, it is still not possible to gain an accurate diagnosis for most back pain sufferers. X-rays tend not to give us useful information so guidelines recommend not using them in most cases. While MRIs provide more useful pictures than x-rays even they are not proving to be as useful in diagnosis as we would like them to be.
Future directions in back pain research?
However, one of the presentations at SBPR hinted at where the research focus as regards imaging (and MRI specifically) could perhaps go. One of Associate Professor Mark Hancock’s suggestions was that we need studies that focus on changes in MRI, in response to treatment (or no treatment). But how do we best measure such changes? (My own research into measuring changes from motion x-rays in response to treatment highlights these measurement challenges – new paper on changes to cervical lordosis after SMT will be published imminently). Which treatments and for whom? Could findings on MRI in a person without back pain predict back pain in the future?
Another presentation, by Dr Judith Meakin of the University of Exeter, provided some exciting insights into how the spine might be better understood using finite element modelling, which (if I interpreted correctly!) is a mathematical approach that aims to reduce the complexity of a system into more simple parts that are easier to understand and quantify. Put even more simply, this technique can be used to produce computerised 3-D models of a person’s spine. Forces can then be exerted on the computerised spine to find out where the spine structures are failing, and therefore contribute to a diagnosis.
‘Be careful of what you vote for’
The lack of knowledge concerning back pain is exemplified by the title to this meeting, ‘Biological Factors in Non-Specific Back Pain’ and the motion of the debate that closed the meeting: ‘Non-specific back pain is a valid concept’. I won’t go into the details but the “for” camp won by a small margin. I might give away which camp I am in when I say a diagnosis cannot be provided by such a label, it simply tells one what it is not i.e. not specific. Without a specific diagnosis we can only guess at what the correct management package is for any given patient and without it, it is hard to see how the global burden of back pain might best be challenged.
In image from left: Associate Professor Wim Dankaerts and Mr Nick Birch (Against); Mrs Elaine Buchanan and Professor Charles Greenough (For)
So, to sum up, the SBPR meeting provided more questions than answers, which is perhaps not untypical of such events. Will another 25 years of research bring us the answers we need?
Excellent post by Roger Kerry, Associate Professor/MSc (Manual Therapy) Leader, Faculty of Medicine and Health Sciences at The University of Nottingham:
Have you thanked a nurse lately? You’ll want to after reading this. Source: Study Confirms What We Knew All Along: Nurses Are Key to Hospital Success. Any thoughts?
British Chiropractic Association Autumn Conference 2015, Bournemouth
I was delighted to have been invited to speak at the British Chiropractic Association’s Autumn Conference 2015, at the Marriot hotel, Bournemouth, perfectly situated to watch the sun glistening on the Channel. The beautiful weather was fitting for a particularly celebratory occasion with chiropractors travelling from all over the world to gather and celebrate 90 years of the BCA and 50 years of AECC. To be included as a speaker alongside some of the top researchers in the musculoskeletal field, and sharing the stage with no less than Professor Alan Breen, was slightly nerve-racking but also a very great honour.
Look Inside: MRI and quantitative fluoroscopy in the future
Alan and I were tasked with discussing what the future might look like as regards imaging in (but not limited to) chiropractic practice. I began by delving a little into the historical background. It is pretty well known that in the same year that D.D. Palmer founded chiropractic, 1895, Roentgen discovered x-rays. It is perhaps less well known that the world’s first hospital-based x-ray department opened no less than one year later – at Glasgow Royal Infirmary. Having previously worked in that hospital (and since Alan is originally from Glasgow) this seemed a neat starting point for the presentation. The department was started by Dr John MacIntyre who is credited with being the first person to observe in situ a kidney stone and a foreign body (a ha’penny swallowed by a child – no Scotsman is going to let a ha’penny get lost like that). Most fascinating for me is that he is credited with taking the first cineradiogram (an early precursor to fluoroscopy) showing the movement of a frog’s legs. So as far back as 1896 did interest begin in using imaging techniques to look inside the body, not just for signs of pathology, but to observe motion.
Imaging in the early-mid 20th century, particularly the use of x-rays, soon became an important part of chiropractic practice. However, taking measurement from static radiographs, as was popular in chiropractic around 50 years ago in North America, have not been shown to be reliable in the assessment and diagnosis of spinal function. In Europe around the same time there was a growing interest not in the identification of putative misalignment of vertebra but of motion abnormalities between the vertebrae, thus motion palpation (particularly under the influence of Henri Gillet) and the use of cineradiography (influenced by Fred Illi). However, while measurements from static films were proving to be much less useful than previously hoped, measurements from cineradiography were not possible at all. This was, however, to change.
Alan Breen first started experimenting with what is now known as quantitative fluoroscopy (QF), taking measurements from motion x-rays, in the 1980s but it was not until the 2000s that computing power was sufficient to make this a reality. QF has since been found to be accurate and reliable in the measurement of inter-vertebral motion in both the cervical and lumbar spines, and has been commercialised in the United States. It should start appearing in European hospitals within the next few years – watch this space. What will be possible with QF is a more accurate measurement of spinal stability to better inform surgical decisions and also the potential to better guide conservative treatment. The examples given from a case series during the presentation included showing that suspected lumbar instability is often not confirmed (therefore the potential to avoid unnecessary fusion surgery) and where it is present there is perhaps an increased chance of good surgical outcomes. Also, manipulation/mobilisation might be better targeted at identified segmental restrictions, and exercise therapy better directed where hypermobile or lax joint motion is present.
Alan’s part of the presentation included discussing what was possible with an open-MRI. Aside it being preferable for claustrophobic patients, the ability to image patients weight-bearing has meant the identification of disc hernia in some patients that would have been missed if imaged lying-down, therefore open-MRI is likely to play an important role in improving the diagnosis of persistent radicular pain. He also touched on diagnostic ultrasound which is showing value particularly in the diagnosis of soft-tissue injury of the extremities.
We are only at the beginning of finding out if the potential of QF (and other imaging techniques) will be fully realised, that of improved outcomes for patients with neck and back pain. Its use, like that of MRI, is likely to be restricted to those patients with particularly problematic spinal pain, but it (and open-MRI/diagnostic ultrasound) is a welcome addition to the diagnostic armamentarium of the chiropractor and other musculoskeletal professionals. And it was developed, not by a massive multinational corporation, but by a member of the BCA at AECC. Now that is worth celebrating.
This is the second and final part of a blog-post where I’d like to take the opportunity to shed some light on what the findings from my study might mean for practising clinicians by addressing questions/comments that have been directed to me that have appeared in social media. By necessity some of the questions/comments are paraphrased and I have tried hard not to misinterpret these. I’m only too happy to (try to) answer any further questions you might have as a result of reading these posts. Please post comments, especially if you disagree! (Although please be polite! It’s fine to attack methods and methodology, not people). The limitations of the study should always be kept in mind when interpreting the ‘clinical implications’ responses to each comment. I look forward to hearing from you!
Comment 3 – ‘[Would have been] more interesting/important to research cervical inter-vertebral rotation in the transverse plane’
This study investigated cervical inter-vertebral flexion-extension (angular rotation in the sagittal plane) as it is not currently possible to use quantitative fluoroscopy to measure inter-vertebral rotation (angular rotation in the transverse plane) or lateral flexion (angular rotation in the coronal plane) due to radiographic superimposition. Axial rotation motion has been measured using CT and biplanar radiography (Bogduk and Mercer 2000) but accuracy can be problematic and radiation doses are high (Anderst et al. 2011).
I agree that, based on clinical experience, it would be interesting to measure inter-vertebral motion during regional rotation. What might make this possible one day is the creation of 3-D models of patients’ spines by combining MRI data with the continuous inter-vertebral motion data provided by quantitative fluoroscopy – but this is probably a long way off! Until measurement methods improve it will not possible to measure the effects of SMT on inter-vertebral motion other than in the sagittal plane (flexion-extension).
It should also be noted that changes in passive regional cervical ROM after SMT have been found to only be short-term (Nilsson et al. 1996). It is worth also considering the other factors at play as suggested in the diagram below:
The ‘black box’ represents the (unknown) underlying mechanisms that account for the outcome after an intervention (Howick et al. 2010). In the above black box are mechanical, neurophysiological and psychological effects (mechanisms) that may be considered to act in isolation or in concert in producing the clinical outcome. ‘Changed IV-RoM’ includes the possibility of a change (increase) in range, or change in another kinematic variable, e.g. IAR location, with or without a change in range.
Figure 4: A suggested mechanistic chain to explain the clinical effects of spinal manipulative therapy (Branney 2015)
Clinical implications? – Current methods only allow for measurement of inter-vertebral angular rotation in the sagittal plane (flexion-extension). Other factors that can influence patient recovery, or otherwise, (Figure 4) should also be considered.
Comment 4 – ‘If there is no difference in intervertebral movement between those with and those without neck pain and we can’t palpate with reasonable certainty which joints are “locked”, and we can’t effect intervertebral ROM and movement with SMT, then why use time on this?’
Good point – doesn’t sound good when you put it like that! It should be said that the findings from my study are not definitive, mainly through it having a small sample size (29 patients, 30 healthy volunteers). Also, the patients in the study were of low/moderate disability – there might be important inter-vertebral motion differences in patients of high neck pain-related disability. Further, differences may not be detected in terms of ROM but other parameters might be important such as IAR (instantaneous axis of rotation) that future studies could measure. However, this doesn’t stop palpation being problematic with studies consistently finding this is not reliable for assessing motion alone; the presence of pain however increases reliability.
Clinical implications? – In the absence of pain it is possible that inter-vertebral motion is not clinically important, or at least we are as yet unable to measure clinically important inter-vertebral motion abnormalities.
Comment 5 – ‘Perhaps it is something else than intersegmental hypomobility we palpate, but should still continue with motion palpation?’
This links with comment 4 and begs the question, if motion palpation is not reliable, what are we feeling when we palpate patients’ spines, and it feels like a joint is restricted? Could we be palpating anisotropic muscle? Might this respond favourably to SMT? We’re back to considering neurophysiological mechanisms…
I have attempted to address a number of comments that were made in social media discussions of my PhD study’s findings. I hope I have not misinterpreted any of these comments. My responses may have opened more questions than provided answers and I’d be really interested to hear from anyone who would like to add their thoughts which may include disagreement with any of the above. Any more questions regarding my PhD study are most welcome. I’d also like to point out this study would not have been possible without the fantastic support of Professor Alan Breen and that of my other supervisors, Professor Jenni Bolton and Associate Professor Sarah Hean. Thank you very much again.
An overall conclusion is that we still do not understand how SMT works but I’d like to finish on this note: despite whatever mechanism SMT works by (see Figure 4), 87% of patients in the study had clinically meaningful decreases in pain and disability, and I’m sure that’s all the patients cared about.
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Assendelft, W. J. J., Bouter, L. M. and Knipschild, P. G., 1996. Complications of spinal manipulation: A comprehensive review of the literature. The Journal of Family Practice, 42 (5), 475-480.
Bialosky, J. E., Bishop, M. D., Price, D. D., Robinson, M. E. and George, S. Z., 2009. The mechanisms of manual therapy in the treatment of musculoskeletal pain: A comprehensive model. Manual Therapy, 14, 531-538.
Bogduk, N. and Mercer, S., 2000. Biomechanics of the cervical spine, I: Normal kinematics. Clinical Biomechanics, 15, 633-648.
Branney, J. (2015) An observational study of changes in cervical inter-vertebral motion and the relationship with patient-reported outcomes in patients undergoing spinal manipulative therapy for neck pain. PhD Thesis, Bournemouth University. (not yet published)
Coronado, R. A., Gay, C. W., Bialosky, J. E., Carnaby, G. D., Bishop, M. D. and George, S. Z., 2012. Changes in pain sensitivity following spinal manipulation: A systematic review and meta-analysis. Journal of Electromyography and Kinesiology, 22 (5), 752-767.
Deitz, A. K., Breen, A. C., Mellor, F. E., Teyhen, D. S., Panjabi, M. M. and Wong, K. W. M., 2011. Kinematics of the Aging Spine: A Review of Past Knowledge and Survery of Recent Developments, with a Focus on Patient-Management Implications for the Clinical Practitioner. . In: Yue, J. J., Guyer, R. D., Johnson, J. P., Khoo, L. T., and Hochschuler, S. H., eds. The Comprehensive Treatment of the Aging Spine: Minimally Invasive and Advanced Techniques. 1. Philadelphia: Saunders, 51-62.
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Kingston, L., Claydon, L. and Tumilty, S., 2014. The Effects Of Spinal Mobilizations On The Sympathetic Nervous System: A Systematic Review. Manual Therapy, 19 (4), 281-287.
Martinez-Segura, R., De-La-Llave-Rincon, A. I., Ortega-Santiago, R., Cleland, J. A. and Fernandez-De-las-Penas, C., 2012. Immediate changes in widespread pressure pain sensitivity, neck pain, and cervical range of motion after cervial or thoracic thrust manipulation in patients with bilateral chronic mechanical neck pain: A randomized clinical trial. Journal of Orthopaedic & Sports Physical Therapy, 42 (9), 806-814.
Meier, M. L., Hotz-Boendermaker, S., Boendermaker, B., Luechinger, R. and Humphreys, B. K., 2014. Neural responses of posterior to anterior movement on lumbar vertebrae: a functional magnetic resonance imaging study. Journal of Manipulative & Physiological Therapeutics, 37 (1), 32-41.
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Padayachy, K., Vawda, G. H. M., Shaik, J. and McCarthy, P. W., 2010. The immediate effect of low back manipulation on serum cortisol levels in adult males with mechanical low back pain. Clinical Chiropractic, 13 (4), 246-252.
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Song, X. J., Gan, Q., Cao, J. L., Wang, Z. B. and Rupert, R. L., 2006. Spinal manipulation reduces pain and hyperalgesia after lumbar intervertebral foramen inflammation in the rat. Journal of Manipulative & Physiological Therapeutics, 29 (1), 5-13.
Teodorczyk-Injeyan, J. A., Injeyan, H. S. and Ruegg, R., 2006. Spinal manipulative therapy reduces inflammatory cytokines but not substance P production in normal subjects. Journal of Manipulative & Physiological Therapeutics, 29 (1), 14-21.
Teodorczyk-Injeyan, J. A., Triano, J. J., McGregor, M., Woodhouse, L. and Injeyan, H. S., 2011. Elevated production of inflammatory mediators including nociceptive chemokines in patients with neck pain: a cross-sectional evaluation. Journal of Manipulative & Physiological Therapeutics, 34 (8), 498-505.
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