Return to work barrier series: Lower back pain
This webinar discusses some of the challenges in managing lower back pain in the return to work setting, including determining when a safe return to work can occur. Dr Matt Brandt examines recent evidence on causation, prevention and rehabilitation for sufferers of work-related back pain.
Dr Matt Brandt is a consultant and specialist occupational and environmental physician who has over decade of experience in Occupational and Environmental Medicine. He has expertise in medical risk assessment, evidence-based rehabilitation advice, and evidence-based analysis of causation of worker’s compensation claims, medico-legal reporting, workplace assessment, toxicology, and health education.
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- Non-specific Low Back Pain:
Evidence-based causation and rehabilitation
Return to Work Barrier Series
Presented by Mr Matt Brandt
Hello everyone. Welcome to today's webinar on low back pain. The topic and expert speaker for today's session is brought to you by the Office of Industrial Relations. The Office of Industrial Relations is committed to driving initiatives across the whole scheme that improve safety, wellbeing and return to work outcomes for both employers and workers. My name is Allicia Bailey. I'm the Manager of Engagement Services and I will be your facilitator for today.
Today's session will focus on non-specific low back pain and the evidence-based causation and rehabilitation. Just to let you know we do anticipate that today's session will go for approximately 50 minutes. We will send all participants a copy of the presentation slides that Dr Brandt uses today following the session and also a recording of the session will be placed on the WorkSafe Queensland website in a couple of weeks which you're more than welcome to access and share and all those types of things.
So you're here today to hear from Dr Brandt. So let's get into it. I have the pleasure of introducing Dr Matt Brandt who is here with us and is our expert speaker for today's webinar having worked in occupational and environmental medicine for over a decade. So enough from me and I'll hand you over to Dr Brandt.
Dr Matt Brandt:
Well good afternoon everyone and thank you for your attendance today. Yeah, it's Dr Matt Brandt here. I'm a Consultant Occupational Physician. I've been working in occupational medicine now for the best part of 14 years and including many years in a role treating and assisting people presenting with low back pain and helping them importantly to remain at work or return to work. I'm also currently an Examiner with the College of Physicians specifically involved in setting standards and examination assessments for doctors who are training to become occupational medicine specialists.
So today's session is really some odds and ends and various topics around the issue of work-relevant non-specific low back pain. So you can see on the first slide the learning goals for today and I hope that we can reinforce and enhance knowledge and understanding of low back pain as the relevance in the context of your management of the return to work of someone who has low back pain.
I've used the term 'work relevant' as opposed to 'work-related' because 'work-related' necessarily implies a causal relationship and as I'll be outlining as we move through the session, there's a lack of strong evidence in the literature to support a clear causal link with physical work demands. By using the term 'work relevant' irrespective of cause we acknowledge that low back pain may affect workability and that work can be difficult because of low back pain.
So the next few slides will outline some basic concepts about the anatomy of the lower back, some definitions including the definition of non-specific low back pain and specifically what it isn't, a time-based classification of low back pain and a brief outline of recent workers' compensation data.
So Anatomy 101 - a nice basic anatomy lesson. Most people have five lumbar vertebrae and there are some congenital and developmental differences. Within the spinal canal the spinal cord generally terminates at around the junction between the first and the second lumbar vertebrae and the lumbar nerve roots exit out of the spinal cord. Out of the spinal column laterally are little holes called [feramoner 00:52:36]. There are deep and superficial spinal muscles and these stabilise the segments of the spine and they also promote mobility of the spine. There are facet joints which are little joints on either side of the vertebrae joining the two vertebrae and these have a joint capsule and they have ligaments as well. There are also ligaments running up and down the spinal column.
So all of the above structures could potentially generate pain. So there's a nerve supply to facet joints, the outer disc, the bone, ligaments, muscles. There are receptors that sense motion and there are also pain receptors that sense damage. Interestingly it's believed that the pain pathways within the nervous system can become sensitised over time contributing to chronic persistent pain even in the absence of ongoing damage.
Okay everyone. Just to get us warmed up, we do have a couple of poll questions which are now on the screen for you. There are four there. It's a simple "yes", "no" answer. So you'll see the ability to answer those on the right hand side of your screen. So there's about 20 seconds. So go through and knock out whether you think the response is "yes", "no" to each of those. The purpose of doing this I guess is just to sort of give us and the presenter Dr Brandt more of an understanding of your knowledge of low back pain and it's also a good sort of segue to sort of introduce you guys to the concepts that Dr Brandt will be covering in this session. So tick away. Once we have a few more responses we'll collate those and then they'll be available for you guys to view on the screen. So it just takes another moment or so.
Okay. It's just thinking guys. So it won't be too much longer. Okay. Here's your answers.
Very good. We're just having a quick sticky-beak. Okay. Good sort of variance in response. I'll hand you back over to Dr Brandt. He'll go back into the presentation.
Dr Matt Brandt:
Yeah, okay. Okay. So what is meant by "non-specific low back pain"? Well, it's really just low back pain that's not caused by 'red flag' pathology. So it's pain involving the lumbar and lumbosacral region. Red flag conditions are uncommon but quite serious pathologies and these can include a lumbar disc prolapse that's resulting in nerve root compression causing sciatica and possibly motor weakness and loss of sensation in the leg. They can include fractures, tumours, infections and inflammatory disease. There are some non-spinal conditions that also refer pain to the back. An example here would be cancer of the pancreas. So non-specific low back pain in probably about 95% of cases of low back pain we don't have a serious cause identified and it's characterised primarily by symptoms although often the term 'strain' or 'sprain' is used by the treating doctor or the patient.
But interestingly MRI studies that are done in the first 48 hours after the onset of acute low back pain have not shown changes consistent with strained muscles or sprained ligaments.
This slide lists a classification of low back pain based on the timeframe. So this isn't a specific diagnosis as such. So for example you could use the term 'acute low back pain' for someone who's had pain for up to six weeks. The classification listed here does have some relevance beyond simple semantics in that as you'll see as we move through the presentation different strategies can be considered depending on where within this classification the worker is. The last bullet point refers to recurrent low back pain which is simply a new episode of low back pain in an individual who has a prior history of low back pain and further on in this presentation we'll return to the issue of recurrent low back pain from a risk assessment and prevention context.
So low back pain is very common indeed. Most people will experience it during their lifetime and about one in three people in this audience have had it during the past month. What we do know is that certain people seem to be more vulnerable to low back pain. The prevalence has probably increased slightly over time and a particular concern probably has been an increase in disability over time associated with low back pain.
Now non-specific low back pain frequently affects work capacity and you'll note that it's variously estimated to cost Australia at least $10 billion annually and this would be made up of treatment costs but also effects on productivity, loss of people from the workforce, early retirement and so forth.
So this is a busy slide, I acknowledge that, and what I'm hoping to convey is there's a continuum of presentation with someone with low back pain. So from someone experiencing symptoms to reporting symptoms, presenting for health care and potentially the condition becoming chronic. In my experience and certainly looking at the literature personal beliefs and attitudes will drive the individual's response to their low back pain, in other words how they interpret their pain and the affect that it has on them, whether they choose to report their pain or seek care, whether they elect to continue to work or rest. So as you move along from the top left to the bottom right of that continuum the less proximal the relationship with work becomes the more likely that there are psychosocial factors and in fact the evolution to chronic pain in disability probably depends more on psychosocial factors than on clinical factors or physical work demands.
This next slides provides a summary of recent claims data on lodged claims for low back pain, strain or sprain in the Queensland jurisdiction. Now accepted low back injuries make up the highest proportion of statutory claim payments for physical injuries and there's a significant common law exposure. Interestingly 60% of claims are in male workers and two thirds of claim lodgements are in the 30 to 59 year age group.
Back strain/sprain – well the most common reported cause for these conditions is body stressing followed by slips, trips and falls.
I'm going to shift direction slightly now and talk a little bit about evidence-based causation. So I guess what does the published evidence-based literature report on the relationship between physical work factors and non-specific low back pain or strain or sprain? I hope that the next few slides will summarise the available evidence but in brief there is a lack of evidence to support a clear causal relationship between physical work demands and low back pain or injury. There's a lack of evidence that the modern physical workload causes permanent spinal damage.
Low back pain symptoms may on the other hand be work-relevant and they fluctuate in response to work. We know that people with low back pain do have more difficulty in managing physically demanding work and workers in heavy manual jobs tend to report more low back pain. So I would accept that physical job demands can cause individual episodes of low back pain but it doesn't mean that work was necessarily the primary cause of low back pain and in fact the physical work demands probably account for only a modest proportion of low back pain in all workers.
The size of effect is modest and I think it's probably less than that of non-occupational factors. Most people in lighter jobs and even those not working will have a similar rate and prevalence of symptoms. So to reiterate workers in heavy manual jobs tend to report more low back pain however the relationship between physical demands is not clear and even people with lighter work report similar symptoms.
So I just thought I'd now convey some results of specific studies and the references are included at the back of this presentation. These studies investigate for an association between physical work demands or exposures and low back pain. So these are generally studies done on large work populations. The experts who review these studies and summarise them report that generally the studies are of limited quality. So it makes it a little difficult to draw firm conclusions. Overall though there appears to be some conflicting evidence as to whether frequent or prolonged periods of bending and trunk rotation are associated with low back pain. So some studies report that there is a significant association whereas others report that there isn't.
There is insufficient evidence that heavy physical work is a risk factor for low back pain and there's insufficient evidence for awkward postures at work as a risk factor for low back pain. Whilst I haven't mentioned it here there was another systematic review of studies investigating the association between spinal mechanical load and back pain and they found that there was conflicting evidence for an association with whole body vibration as well.
So the studies have also generally indicated that there's insufficient evidence for standing and walking at work as a risk factor for low back pain and there is strong evidence that sitting is not a risk factor for low back pain.
So what conclusions have I drawn? Well it seems to me that the physical injury model alone will not explain the incidence of low back pain at work. There's probably a number of other factors of relevance here including what we've already mentioned as background of a high prevalence of low back pain in the population and there are likely to be personal or constitutional factors and psychosocial factors at play as well.
This next slide summarises the available literature on the association between occupational psychosocial factors and low back pain but also disability associated with low back pain. There is reported to be strong evidence that if there is a lack of supervisory and social support in the workplace that is a risk factor for an increased risk of absence from work for someone who has work-related low back pain.
There's reported to be a weak association between personal job satisfaction, the risk of low back pain and there is insufficient evidence for organisational aspects of work or work stress being a specific risk factor for low back pain. Organisational aspects of work really refer to a number of things such as job security, time pressure, conflicting demands, work control, quantitative and qualitative demands of work, skill discretion and so forth. The term 'work stress' here really refers to when demands are perceived as exceeding the available resources and these can include higher job demands in association with low job control and low social support at work.
So the next few slides will briefly summarise or mention the evidence available on measures at the workplace addressing physical work demands and how effective these measures might be in reducing the risk of low back pain. So these studies are typically conducted on work populations and again they're of variable quality. The idea is that they compare the effects of different interventions between different work groups, typically a study and a control group and at the end of the study what you really want to know is is there a significant difference in the outcome between these groups and in this case it would reporting of low back pain or low back pain injury or disability from low back pain.
The summary findings are very interesting. What they're saying is that there really is a lack of strong evidence that workplace interventions that simply address physical factors have any significant effect on the rate or prevalence of low back pain. There is no evidence that the use of lumbar supports and education of themselves are effective tools in minimising the risk of low back pain or preventing low back pain at the workplace. There have been studies done on the effectiveness of combining manual handling assisted devices with training and they looked at outcomes of back pain and back-related disability and absence from work. What they found was that there was no significant difference between those outcomes in groups who received training on lifting techniques and has assistive devices compared to a control group that either had no training or assistive device or a back belt for example. A systematic review of low back pain for which the references are available again at the back end of the presentation have found that there was no evidence that decreasing or eliminating lifting at work altered or had any significant impact on the incidence of low back pain in the working populations.
So focusing solely on physical job determinants does not appear to be of itself an effective primary preventative measure and I think that really relates to the complexity, the biopsychosocial nature of low back pain. There are likely to be a number of other factors as previously touched on. So personal or constitutional and psychosocial factors. There is limited published evidence and professional consensus that a consultative joint worker/employer initiative can reduce the number of reported back injuries and sickness absences but I won't be addressing those types of interventions during this session.
Look in terms of primary preventative measures at the workplace there's lots of very good and sensible reasons to be continuing to proactively address physical and work design hazards and engineer out the physical hazards. For one thing you're going to enhance the wellbeing and productivity of your workforce. You're going to potentially reduce the risk of other injuries like shoulder injuries but also importantly you need to be adapting the work to the capabilities of a diverse and increasingly ageing workforce.
So this somewhat busy slide outlines I think the expectations and steps of the first one or two occupational medicine assessments of an individual who presents with acute low back pain. As I understand it the key requirements are initially to screen for red flag pathology, to assess for the presence of lumbar nerve root compression and that's actually quite important because that will drive the treatment down a different pathway. To screen for yellow flags and to explore for personal and occupational psychosocial factors that may have an impact on returning to work or staying at work, yellow flag assessment is important and it should be done as early as possible. The reason for that is that we do increasingly realise now that the yellow flags are probably one of the most significant factors on whether someone will return to work or stay at work and in fact on the length of disability. But from a positive perspective if we can identify and address them we can certainly facilitate that return to work.
Now there's strong evidence that the first conversations between the treating doctor and the patient can have a more profound effect on the long-term outcome than any treatment that can be offered. There's strong published evidence that the advice to continue normal activities including early return to work or staying at work, performing as near to normal activities is associated with much better longer term outcomes and I'll return to that issue a little bit later on. There's also moderate published evidence that that sort of advice, if it's supplemented with educational interventions to overcome fear avoidance beliefs and encourage self-responsibility for care will also enhance the long-term outcomes.
I wanted to briefly mention radiology tests and in general, and there's always going to be some exceptions, but in general diagnostic imaging isn't recommended outside of the above circumstances for someone who presents with acute low back pain. It would rarely have any impact on treatment or on prognosis and for the person who is then having an X-Ray or a CT scan it is exposing them to ionising radiation which is not without risk. For someone who has sub-acute or chronic low back pain imaging may be valuable. So for example an MRI scan could potentially reveal some discrete focal dispathology that could be generating pain and amenable to treatment, but for the large part even in the chronic situation the findings may not be terribly helpful. Why is that?
Well age-related changes are commonly reported on X-Rays and CT scans and these can include disc bulge or prolapse, annular disc tear, facet degeneration, osteophytes etc. Now these changes become more pronounced with increasing age and they're present from the second and third decade of life onwards. They have almost nothing to do with activities, the age of onset and degree and rate of development of these changes are largely genetically determined and they certainly haven't arisen as a result of trauma or wear and tear.
A substantial proportion of people without back pain will have these changes and conversely someone with severe low back pain may have a pristine spine on imaging. I wanted to just make a few important observations and this is in relevance to I suppose the work context. Firstly there's generally a poor correlation between age-related or degenerative changes and symptoms of low back pain or work incapacity. Secondly diagnostic labelling from a radiological investigation can have a detrimental effect on outcome. It could potentially reinforce illness behaviour. It may reinforce fear avoidance behaviours and it may have an impact on recovery and return to work. So it may delay the return to work. So we never make an assessment based on an X-Ray generally.
So what's the outcome doc? What's the prognosis? Look in most cases it's going to settle fairly quickly and in fact 90% of episodes of low back pain will settle within six weeks. Unfortunately a small proportion of people do go on to suffer sub-acute or chronic low back pain.
So this slide summarises some of the aspects of treatment and rehabilitation that are relevant to return to work for someone who's presented with acute non-specific low back pain. I just want to I suppose reinforce the previous point I made that prescribed medical treatment as such has little impact on long-term work capacity and I believe that the first few conversations that are had with the worker can have perhaps a greater impact. It's clear that the educational interventions and advice provided by the treating doctor and reinforced by other important stakeholders can address beliefs and attitudes and may facilitate an early return to work and may reduce further work loss due to low back pain.
Until the late 1990s advice to take it easy and rest was a common treatment approach and the exact nature of the rest varied. But often it meant staying in bed full time, only taking trips to the bathroom or perhaps the kitchen. But it's actually become evident now that extended periods of bed rest are potentially harmful because they may lead to deterioration of muscles and body functions and will more likely than not delay recovery.
Advice to continue activities of daily living as normal as possible despite pain generally leads to shorter periods of work loss, fewer work recurrences and less work loss over the next 12 months as opposed to the traditional biomedical model which advised rest and letting pain guide the return to normal activity. Part of the advice may need to include a reassurance that light activity will not result in further injury and actually probably enhances recovery. This is backed up by published research. The Cochrane Systematic Review reported that moderate evidence that individuals with acute low back pain may experience small benefits in pain relief and functional improvement if they follow the advice to stay active compared to following advice to rest in bed.
So in regard to medication often the use of medication or prescription medication will be driven by patient preference or the clinical expertise of the treating doctor. There's no clear evidence as to which particular type of medication is more efficacious but there's moderate evidence that non-steroidal anti-inflammatory medications can provide some relative benefit for people suffering with acute low back pain. I wanted to briefly mention opioids. So these are things like Panadeine Forte, Tramadol and Oxycontin. Now there's evidence that if these opioids are prescribed in the acute phase they're associated with an increased risk of a delayed return to work outcome and disability. There's certainly lack of evidence that these are effective for persisting or chronic pain and in fact the persistent use of opioids is associated with an increased risk of adverse physical and mental health outcomes.
In the work context I think this is really important. If your worker has been prescribed opioids for acute low back pain particularly if the dose is varied or increased in the short term there is a significant risk of impairment and that increases the risk of incident and injury potentially and particularly if there's a safety critical work environment. But it also potentially increases the risk of impairment resulting in reduced efficiency.
I also wanted to highlight the use of benzodiazepines which are sometimes prescribed to relieve back spasm. Now there's no actual evidence that spasm contributes to pain or can be reliably diagnosed and from my perspective the concern in the workplace is that the use of benzodiazepines in this nature is most definitely associated with a significantly increased risk of impairment which again potentially increases the risk of workplace incident and injury and potential risk to others at the work and the general public. So my advice to participants is that if you have concerns about the safety of an individual who has returned to work and they're taking prescribed opioids like potent opioids and/or benzodiazepines please seek the expert advice of a specialist Occupational Physician to ensure that this return to work can be conducted in a safe manner.
So moving onto exercise therapy, look for acute low back pain there's probably no significant difference in groups of patients who've exercise therapy as opposed to either no treatment or other conservative treatments. I think for sub-acute low back pain there is some evidence that a graded exercise and work activity program does improve the return to work outcomes and in fact probably reduces the risk of recurrent low back pain down the track. Certainly for people with chronic low back pain who are often quite deconditioned exercise therapy does appear to be slightly effective in both reducing pain and improving function.
Now in regards to manual therapy or hands-on treatments it may provide benefit to help accelerate recovery in the short term. Research has indicated that manipulative therapy has not however been shown to be relatively more effective than placebo or other treatments beyond about three weeks of treatment. So it doesn't really result in any greater long-term gain. Now a client recently asked me about the effectiveness of lumbar supports or back braces. Now I've previously highlighted that there doesn't appear to be any benefit in back braces reducing the risk of low back pain or injury and it's unclear from the literature as to whether back braces or lumbar supports are more effective than no intervention or other intervention in actual treating low back pain.
Just briefly touching on the multidisciplinary strategies, there's two studies that I found on the effects of multidisciplinary pain management and rehabilitation. These were focused on people who have sub-acute low back pain. Now those studies were of low quality. What they did find though was that there was moderate evidence that this sort of multidisciplinary biopsychosocial strategy including a workplace visit or perhaps a more comprehensive occupational intervention does help people return to work faster. It reduces the number of sick days in 12 months following the intervention and it alleviates the subjected disability of the worker.
Thank you Dr Brandt. Okay participants we're going to throw it over to you guys now. So this is really an opportunity for you who are probably doing emails on the side or planning Christmas parties to jump back in and use this as a facility I guess to compare yourself against your peers. So what we want to know is in your experience how long on average has it taken to get your injured workers back to work with non-specific low back pain, lower back pain or strain and sprain injuries? So jump on and let us know. There is no real right or wrong answer. Like I said this is just an opportunity for you to see how you fit in comparison to your peers and with other guys in other industries managing these types of industries. So we've got about a few seconds left and we should see the results.
Okay so it's quite varied. I guess the most predominant one is two to four weeks which is good but probably more varied than I was expecting. So that's quite interesting. Like I said there is no one size fits all for these types of injuries. So it is kind of I guess an indication of the varying degrees in terms of recovery. So what we're going to do now is I'm going to hand you back to Dr Brandt. He's gone through quite a thorough intro to the topic which is fantastic. We're going to move into the second half of the session which is focusing on rehab return to work and really provide you with an introduction to some guidelines as to how you guys as employers to help get your workers back into the workplace following these injuries.
Dr Matt Brandt:
Right. That's really interesting. Gosh more than 50% of participants reported that on average it takes more than two weeks for workers to get back to work with low back pain. Look I've touched on treatment issues but obviously it doesn't occur in isolation. It should occur in parallel with the return to work and most people with non-specific low back pain are able to continue working or return to work within a few days or at most weeks despite persistent symptoms. Avoidance of work until you're 100% recovered is unrealistic and it's unhelpful in most cases. Because work almost always has clear benefits for physical and psychological health workers should be allowed and helped to return to work as soon as possible.
People don't need to wait until they're completely pain free before returning to work. If no one returned to work until they were 100% symptom free there'd be a whole lot of people still at home and only a minority of people with low back pain would actually ever, ever return to work in their lifetime.
There's very good evidence from published research now that staying at work or an early return to work even with some persistent symptoms results in a better outcome with a relatively reduced likelihood of reinjury, a reduced rate of recurrence and sickness absence over the next 12 months. In contrast specifically to people who rest and avoid work in that early period. Referring to the AFOEM Consensus Statement on the Health Benefits of Work there's now strong evidence that the longer a person is off work with low back pain the lower their chances of ever returning to work irrespective of any further treatment. There's little evidence with these people who are chronically disabled that they have any significant physical differences in their backs. There shouldn't really be any insurmountable physical barrier to rehabilitation.
So I was just going to touch briefly on some of the things and strategies that can be put in place to help rehabilitation and return to work. I recognise that some of the other webinars have also addressed this and you'll probably have further webinars on these sorts of matters.
In terms of what can be done at the organisational level there is moderate published evidence and buy-in from senior management that communication, cooperation and agreed return to work goals involving the key stakeholders are associated with better return to work outcomes. There's general consensus and some limited published evidence that organisational or management strategies and interventions may reduce the duration of work loss. However there is possibly the strongest evidence that the provision of temporary alternative or modified work duties or ergonomic workplace adaptations will facilitate an early return to work and can reduce the time loss from work. Simple task modification may be all that is required to facilitate a return to work. There may in some cases be benefit involving a rehabilitation provider and there's moderate evidence that a combination of optimal clinical management, a rehabilitation program and organisational interventions themselves are more effective overall than single elements alone.
I just wanted to briefly return to the subject of multidisciplinary programs and for someone who's got sub-acute low back pain who is having difficulty returning to normal activity whether it be ADLs or work at 4‑12 weeks, a more formalised program may promote return to work and reduce the risk of chronic incapacity. In that case I would certainly endorse involvement of an Occupational Physician who can medically assess the individual and review potential barriers both in the individual and at the workplace to a return to work and there may be benefit from involving a rehab provider.
Now the elements of multidisciplinary rehabilitation involve a combination of things. They involve progressive exercise and that can be a combination of reconditioning aerobic exercise of core stability, recognising that a couple of things happened. The core stabiliser muscles can shrink away a little bit when people have low back pain but also certain individuals might reduce their activity and become deconditioned. So a progressive exercise program in conjunction with a graded return to or resumption of ADLs and work activities but also provision of education and some psychological inputs such a CBT to really identify and address any barriers such as fear avoidance belief. So all these things put together can have a significant beneficial impact on long-term outcomes.
I think it's also briefly touching on work hardening or conditioning programs. We hear of them and we often see them being implemented. There are some published studies that report on the effectiveness of these interventions and the sorts of interventions mainly involve a combination of graded exercises so work-related graded exercises that aim to increase back strength and flexibility and general fitness together with a set date for return to work. In fact it's of relevance to today's group. It may actually be that the inclusion of workplace visits or the implementation and support of the intervention at the workplace may be the component that renders the conditioning program most effective.
Now for workers who have acute low back pain a work hardening program may not have any significant effect on the duration of absence from work. For workers with sub-acute low back pain there is some conflicting evidence as to whether the duration of work absence is reduced with a physical conditioning program versus usual care and for workers with chronic low back pain there appears to be a small effect in reducing work absence compared with usual care when followed up at 12 months.
So now I want to move onto some risk management issues and this is what in my practice I'm frequently asked to provide advice on. So, we're talking about non-specific low back pain here as opposed to a situation where there is objective, significant pathology. So for example a disc prolapse where there's a nerve recompression. So someone with non-specific low back pain there is no evidence of a predictable risk of harm in returning to normal work activity. There is no published evidence that any level of activity is harmful to those with ongoing non-specific low back pain and I think the key issue is perhaps one of tolerance and to a lesser degree capacity bearing in mind that capacity can reduce over time because some people become deconditioned as a result of reduced activity.
This slide quotes from the Medical Disability Advisor Guidelines and there's a reference to that at the end of the presentation. This is specifically in regards to non-specific low back pain or lumbar spine strain or sprain and what it says is this. "Individuals with severe back pain whether this is called 'back pain or 'sprains or strains' whose normal work duties require extensive lifting or bending may appreciate temporary reassignment to lighter or sedentary duties with a scheduled decrease in these activity guidelines over time." In other words the restrictions are being reduced over a period of time. "Usually a return to full activity is possible at six weeks for those with moderate duty jobs and to very heavy work by three months", and this is the interesting thing. "If a minor trauma event has created a strain or sprain studies on wound healing indicate that by six weeks muscle and ligament injuries have done most of their healing and that by 12 weeks muscle and ligaments have regained 90% of their pre-injury strength." So I think these guidelines are fairly clear.
I want to contrast that with the very different situation where someone has objective evidence of spinal pathology causing symptoms, signs and impairment and the examples I've given are someone's got an intervertebral disc prolapse in the lumbar spine that's evolving and it's causing nerve recompression. So it's causing severe sciatica. There might be loss of feeling in one or both of the legs and there's certainly going to be some motor weakness. So for that individual they have a vulnerable spine and certain physical work exposures may now become significantly hazardous. So I think in that circumstance there is a reasonable medical risk management basis to recommend restrictions. So for example certain postures and sustained physical demands may in this case predictably increase the risk of aggravation of symptoms and the underlying pathology.
So for someone who's got an evolving lumbar disc prolapse with nerve recompression activities that involve a combination of bending and lifting or sustained repetitive bending, very heavy lifting or even whole body vibration, so for example off-road mobile machinery, so these are hazardous activities in that situation potentially because of the high level of pressure exerted at the low part of the spine and is now vulnerable because of pathology.
In that situation if there are any concerns about fitness for duty from a medical risk management perspective I would certainly endorse involvement of an expert Occupational Physician to perform a medical and workplace risk assessment. So again just contrasting those guidelines with the previous guidelines for someone with non-specific low back pain, they're two slightly different situations.
I'm going to change topics now and move onto recurrent low back pain and I've no doubt that a number of participants have managed workers who have recurrent low back pain resulting in incapacity and certainly this is a common reason for workers to be referred to my practice and to colleagues in the industry. Now there's a number of published studies investigating recurrent low back pain and there's strong evidence that the single most consistent predictor of future low back pain is a previous history of low back pain. Unfortunately there's no clear threshold that's been established.
The other thing that's clear from the literature is that most people who experience activity limiting low back pain are vulnerable to experiencing recurrent episodes. Now there's a very wide reported recurrence rate at one year of about 24-80% but also I've just highlighted there on that slide that other studies have shown from pooled data that if you follow up workers who've had an episode of low back pain over a period of one to three years then there's about a 20-75% incidence of recurrent low back pain. In that group about 20-40% are likely to require treatment and there's a 10-20% likelihood of work incapacity.
It's very difficult to generalise that data because they're all population-based studies. They're not dealing with individual people and that's the difficulty is to generalise that data to an individual risk assessment. It is difficult to accurately define the future risk in an individual but what we do know is that the risk of recurrent disabling low back pain is increased in someone who has had a more recent episode, if there's been more than one recurrence or flare-up, if there's been previous work incapacity as a result of low back pain and interestingly if there's been associated leg pain.
Here's what's interesting. It doesn't appear that physical work exposures are the most or the strongest predictor factor in recurrent low back pain. So someone who has that sort of vulnerability is more likely to experience recurrent low back pain irrespective of the work performed. Again it's probably because there are other complex biopsychosocial factors, so personal, constitutional, psychosocial factors that may drive that increased risk of recurrence.
So what can be done to reduce the risk of recurrent low back pain? If we go back to the evidence and in fact exercise is probably the only personal measure that the individual can perform that will have a consistent limited effect on the prevention of new episodes of low back pain. It's probable that a maintenance program of core stabilising muscle strengthening exercises can reduce the risk of recurrent low back pain and a Cochrane Review which I've included as Reference 9 basically looked at the effectiveness of what's known as post-treatment programs. What they found was that such a program can reduce the risk of recurrent low back pain by 25%. There was a 22% reduction in the number of recurrences of low back pain and the time to recurrence prolonged. The number of days of sick leave was reduced over about two years.
The post-treatment program itself, when the Cochrane reviewers looked at it there were so many different types of exercises and different types of programs that it was very difficult to specify which particular exercise would be beneficial. It was felt that any sort of general exercise, whether it's stretching or strengthening or endurance training or posture education could actually be adequate. But as I've previously mentioned from a workplace perspective an early return to work is also reported to be associated with a significantly reduced likelihood of recurrence and disabling recurrence in the subsequent 12 months. As I've previously touched on for someone who has sub-acute low back pain some form of multidisciplinary rehab program may also facilitate recovery and reduce the risk of recurrence in the long term.
If your workforce includes workers who have more than one episode of disabling low back pain attributed to work I would certainly advise again an expert Occupational Physician medical and workplace risk assessment.
I just wanted to briefly touch on chronic low back pain and what the research says about it. None of the studies that have been reviewed have found any physical factor that can reliably predict which person with low back pain will go on to develop disabling chronic low back pain. In some cases there may be objective evidence of internal lumbar disc disruption or facet joint pathology that's generating persistent pain and that can be amenable to very focused interventional treatments. But for the large part it's probably not the case. In other cases there can be imbalances in muscle activity on each side of the spine and pelvic area and it's also hypothesised as I previously touched on that there can be changes in the central nervous system that can increase the sensitivity of normal signals so that normal mechanical activities are perceived as painful and high sympathetic nervous system activity for example with mental stress that can also magnify neural sensitivity and also highlight the emotional effect of component of pain and suffering.
There's a whole bunch of other potential predictors of chronicity, a very long list and that can include age greater than 50 years, poor general health, psychiatric comorbidity, fear avoidance, catastrophisation, high levels of maladapted pain coping behaviours, a high level of functional impairment of baseline, chronic widespread pain, beliefs that low back pain is caused by work and expectations about an inability to return to work. So you can see how psychosocial factors form a great part of that potential nexus leading to chronic low back pain and disability.
What I find in my practise and from reading literature is that persistent chronic low back pain tends to develop into this sort of combination of physical, psychological and social disability. Patients with chronic low back pain encounter significant difficulties in returning to work or staying at work and coping at work. So for that reason that's why the sort of multidisciplinary rehabilitation can be effective in improving functioning.
For the benefit of the audience what I wanted to emphasise here is that in the absence of those red flags or significant objective pathology causing chronic low back pain I do believe that staying at work or returning to work should be a reasonable objective. It's not easy but I think that should still remain the goal.
So this is the summary slide, the take-home messages. Look non-specific low back pain is common. For the large part it's benign and it's rarely caused by any significant pathology and self-limiting in most cases. So 90% of people are recovered by about six weeks. There is certainly a lack of evidence in the literature and there have been a lot of studies done about this area regarding a significant causal relationship between physical job demands and low back pain or low back strain. In fact as you recall there's a lack of strong evidence that preventative interventions focusing solely on physical factors have any significant bearing on the future rate of low back pain.
I hope that I've been able to convey the benefits of a proactive approach to rehabilitation and returning to work and that the majority of individuals even with some persistent symptoms should be able to stay at work or return to work very soon. In fact they have a better and far better long-term outcome than those who rest and become functionally disabled.
So thank you very much indeed for your participation.
Thank you so much Dr Brandt. To the participants Dr Brandt covered a fair bit of literature and research and things like that. So this slide containing all the references used throughout the presentation will be included in what we send out to you. So if you did want to have a sticky-beak into anything a little bit further those references and resources will be provided to you. So hold tight for that.
Now just in case anyone's got last minute burning questions shoot them through using the question chat box on the right hand side of the screen. Just while I give you guys an opportunity to do that I wanted to touch base and let you know that the Office of Industrial Relations only has two more webinars for 2015. So we are getting towards the tail-end of this year's initiative.
Registrations for both of these webinars are now open. So feel free to jump on and secure your spot by going to the 'what's on' page on the WorkSafe website sorry. So we've got one more tomorrow. That's on the Getting Back to Work Series: Workplace Buy-in for sustainable return to work with Anita Johnston and this particular webinar is following on from her earlier webinar in the year which was Employer Buy-in for Sustainable Return to Work. So if you're interested that is tomorrow at 12:00 o'clock.
We've also got another one on the 9th which is the Health and Safety Series: Introduction to Ergonomics with Michelle James and Pam Knobel. So they're going to wrap us up for the year.
So I think we have actually run out of time and I am mindful that you guys have probably far better things to do and you've got competing priorities. So we will let you go. If you did have a question and we weren't able to get a response out to you we will try and work with Dr Brandt following this session and get a response to you as quickly as we can but this is the end of the webinar.
So Dr Brandt thank you again so much. Your expertise was so evident throughout all of that. So greatly, greatly appreciate having you and we'd love to have you back in the new year if you're available.
To the participants you guys have been fabulous and your feedback is so valuable to us. So let us know if our initiatives are actually hitting what you want. So please take the two seconds to complete the survey that we will shoot you through to. If you want to connect with Rehab and Return to Work Coordinators to share information and also share the initiatives that are available to you guys, jump onto our Facebook page because that's predominantly where most of this stuff is advertised just to make sure you don't miss out.
So if you're not attending any of our sessions later in the year over the next two weeks sorry, wish you a merry Christmas, a safe new year and we'll see you in 2016.
So on behalf of the Office of Industrial Relations thanks so much and bye for now.
[End of Transcript]
- Non-specific Low Back Pain:
- Last updated
- 13 October 2016