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Psychosocial Symptoms, Chronic Low Back Pain and Inflammation

Written by Kieran Macphail on . Posted in Back Pain and Diet, For Diet and Lifestyle Professionals, For Everyone!, For Health Professionals, Low back pain, Mindfulness, Nutritional therapy, Orthopaedic Medicine

Highlights

 

  • Psychosocial symptoms are important predictors of those that do worse with chronic low back pain.
  • Currently the prevailing view is that psychosocial symptoms drive systemic inflammation.
  • Psychosocial problems increase inflammation, and inflammation increases psychosocial symptoms.
  • Psychosocial treatments decrease inflammation and reducing inflammation improves psychosocial symptoms.
  • The relationship is bidirectional and we should remember this when dealing with patients with psychosocial symptoms.
  • Explaining this relationship to patients may reduce the stigma associated with psychosocial symptoms.

 

Background

 

Since the turn of the century there has been an increased awareness of psychosocial symptoms in chronic low back pain (CLBP) patients. It’s well established that CLBP patients with psychosocial, psychological and social, risk factors have poorer outcomes and increased management costs (Grimmer-Somers 2006, Nicholas et al. 2011). The term “yellow flags” was originally used to describe psychosocial risk factors that predict disability in LBP patients. Yellow flags are now included in most LBP guidelines although there is wide variation in suggestions in how to assess and manage these patients (Koes et al. 2010). This is discussed elsewhere on this site, see article on Yellow flags and CLBP. These risk factors are predictors of return to work and disability in CLBP patients (Glattacker et al. 2013). They can be identified using a questionnaire or a clinical diagnosis (Watson and Kendall 2000). Questions cover beliefs that are associated with delayed return to work and disability. These include fears about pain, injury, recovery and being despondent or anxious. It is suggested that having a few strongly held negative beliefs or several weaker ones could be used to identify at risk patients (Nicholas et al. 2011). These beliefs can be viewed as “thought viruses” (Butler and Moseley 2013) and increase a patient’s perception of threat and modern neuroscience suggests that pain is the conscious interpretation that tissue is in danger (Moseley 2007).

 

Inflammation and Psychosocial Symptoms

Inflammation and psychosocial symptoms are intimately related. Those with higher levels of systemic inflammation have more psychosocial symptoms (Hänsel et al. 2010) and Miller at al (2014) found that psychosocial treatment reduces levels of inflammation. Generally this relationship has been viewed top down, e.g. the brain affecting our systemic inflammation level. However, systemic inflammatory molecules signal the brain to induce sickness behaviours and negative affect (negative emotions and a negative view of self) (Walker et al. 2014). It’s also well established that anti-inflammatories improve psychosocial symptoms such as depression (Gallagher et al. 2014, Iyengar et al 2013). Thus perhaps we should consider this as a bidirectional relationship.

Peripherally cytokines, proteins of the immune system that communicate with other cells, interact with afferent nerves which send signals to their primary projection area. For example the nucleus of the tractus solitarius for vagal afferents. From here it propagates to secondary projections including the paraventricular nucleus of the hypothalamus and the central nucleus of the amygdala, where it can contribute towards negative affect. This partially occurs, as there is some active transport of cytokines across the blood brain barrier. With increased levels of systemic inflammation, active transport of cytokines across the blood brain barrier is increased further.

Tissue damage in the body is responded to by two main systems, pathogen associated molecular patterns (PAMPs) and damage associated molecular patterns (DAMPs). In a cold it is PAMPs that give rise to the illness behaviour associated with having cold symptoms. We all tend to withdraw from activity, feel a bit ugh, and have a kind of minor low level depression with a cold. With back pain it is DAMPs that give rise to the illness behaviours. Yet with CLBP we treat patients as if they are making conscious decisions to withdraw from activity. Potentially if we understand these underlying mechanisms and view the behaviours that arise secondary to this condition as like that of an infection we might have more empathy towards understanding the CLBP patient.

The association between peripheral inflammation and depression was initially established in patients undergoing cytokine therapy. Immune stimulating therapies such interferon therapy in those with hepatitis C or malignant melanoma produced initial sickness behaviour and then a transition to depression in many patients (Raison et al. 2007). Capuron et al. (2002) established that the anti-depressant paroxetine only reduces sickness behaviours and not the cognitive and affective aspects of depression. It appears that it is prolonged elevated levels of inflammation that are required for the transition of sickness behaviour in to depression. Obviously there are multiple mechanisms interacting here and to focus on one to the exclusion of others would be negligent clinically.

In healthy individuals typhoid vaccination induces negative mood post-vaccination (Wright et al., 2005), stops the normally occurring improvement in mood as the day progresses (Strike et al., 2004), increases brain activity in depression-related regions such as the subgenual cingulate cortex, and decreases its connectivity to the amygdala, medial prefrontal cortex, and nucleus accumbens (Harrison et al., 2009). Similarly, in healthy mice increasing levels of inflammation induce initial sickness behaviours, which subside, and transition to depressive symptoms following prolonged increased inflammatory levels (O’Connor et al. 2009).

Inflamamtion is closely linked to the pain experience. Peripheral inflammation can propogate signals to key brain areas involved in pain such as the central nucleus of the amygdala. Pro-inflammatory cytokines also lower nociceptor thresholds throughout the body decreasing the temperature, pressure or pH stimulus required for nociception. Further low levels of anti-inflammatory cytokines, such as Il-10 may also lower nociceptor thresholds (Uceyler et al. 2006).

Norman et al (2010) investigated the effects of social isolation on depressive symptoms in mice post nerve injury. Only the socially isolated mice developed depression and increased inflammation in the brain seven days later as measured by Interleukin-1β. Mice that underwent social isolation but received oxytocin did not develop increased inflammation or depression. Conversely, mice that were socialising but received an oxytocin antagonist developed depression and elevated brain Interleukin-1β. This, at least in mice, very clearly demonstrates the importance of social interaction, a positive psychosocial input, on inflammation; and points to the central role of oxytocin, at least as a marker, in this process.

Tryptophan is required for the production of the “happy” neurotransmitter serotonin. Decreases in tryptophan have been theorised to cause depressive symptoms and there is some support for this (Dell’Osso et al. 2016). Under increased levels of systemic inflammation there is increased activity of indoleamine 2,3-dioxygenase, an enzyme that converts tryptophan in to kynurenine, Thus there is less available for serotonin production. In animal studies the induction of inflammation has been shown to produce increase indoleamine 2,3-dioxygenase activity, decreased circulating tryptophan and a progression from sickness behaviour to depression (O’Connor et al. 2009).

Increased activity of indoleamine 2,3-dioxygenase ultimately leads to an increase in the NMDA receptor agonist quinolinic acid. Increased glutamate and its receptor subtypes including NMDA have been implicated in the development of both chronic pain and depression (Mitani et al 2006). Glutamate is primary neurotransmitter in nociceptor afferents.

This evidence clearly indicates the role of peripheral inflammation to directly impact our behaviour. This needs to be viewed within a broad context and the central process contributing to illness behaviours must also be considered. Nonetheless this information can be powerful for patients in taking the pressure off themselves to change these behaviours under the illusion that they are 100% under our control. This can be quite empowering in a perverse way and allows for a more open and honest discussion of these behaviours with patients as the pressure for responsibility and feelings of being judged are decreased.

 

What does this mean for treatment?

Psychosocial interventions such as CBT, pain neurophysiology education and mindfulness are still useful when viewing this relationship as bidirectional. In my clinical experience when they are offered these treatments patients often feel like they are being judged, it’s in their head, they should think positively and pull themselves together. Explaining this relationship to patients removes some of the stigma associated with psychosocial symptoms and pain. When patients view these changes in mood as similar to when you have a cold it is easier for us to discuss these symptoms and patients often feel like it becomes more manageable.

 

If this article has been useful at all please feel free to donate to help with the running of the site. Donations of £1 are really appreciated and help me keep the site add free, many thanks.




References

Butler, D.S., Moseley, G.L. (2013) Explain Pain. London: Noigroup Publications.

Capuron, L., Ravaud, A., Neveu, P.J., Miller, A.H., Maes, M. and Dantzer, R., 2002. Association between decreased serum tryptophan concentrations and depressive symptoms in cancer patients undergoing cytokine therapy. Molecular psychiatry, 7(5), 468.

Dell’Osso, L., Carmassi, C., Mucci, F. and Marazziti, D., 2016. Depression, Serotonin and Tryptophan. Current pharmaceutical design, 22(8), 949-954.

Gallagher, P.J., Castro, V., Fava, M., Weilburg, J.B., Murphy, S.N., Gainer, V.S., Churchill, S.E., Kohane, I.S., Iosifescu, D.V., Smoller, J.W. and Perlis, R.H., 2012. Antidepressant response in patients with major depression exposed to NSAIDs: a pharmacovigilance study. American Journal of Psychiatry, 169(10), 1065-1072.

Glattacker, M., Heyduck, K., Meffert, C. (2013) Illness beliefs and treatment beliefs as predictors of short-term and medium-term outcome in chronic back pain. Rehabilitation Medicine45(3): 268-76.

Grimmer-Somers, K., Prior, M., Robertson, J. (2008) Yellow flag scores in a compensable New Zealand cohort suffering acute low back pain. Journal of pain Research, 1:15-25.

Hänsel, A., Hong, S., Cámara, R.J. and Von Kaenel, R., 2010. Inflammation as a psychophysiological biomarker in chronic psychosocial stress. Neuroscience & Biobehavioral Reviews, 35(1), 115-121.

Harrison, N.A., Brydon, L., Walker, C., Gray, M.A., Steptoe, A. and Critchley, H.D., 2009. Inflammation causes mood changes through alterations in subgenual cingulate activity and mesolimbic connectivity. Biological psychiatry, 66(5), 407-414.

Iyengar, R.L., Gandhi, S., Aneja, A., Thorpe, K., Razzouk, L., Greenberg, J., Mosovich, S. and Farkouh, M.E., 2013. NSAIDs are associated with lower depression scores in patients with osteoarthritis. The American journal of medicine, 126(11), 1017-e11.

Koes, B.W., van Tulder, M., Lin, C.W.C., Macedo, L.G., McAuley, J., Maher, C. (2010) An updated overview of clinical guidelines for the management of non-specific low back pain in primary care. European Spine Journal, 19(12): 2075-2094.

Miller, G.E., Brody, G.H., Yu, T. and Chen, E., 2014. A family-oriented psychosocial intervention reduces inflammation in low-SES African American youth. Proceedings of the National Academy of Sciences, 111(31), 11287-11292.

Mitani, H., Shirayama, Y., Yamada, T., Maeda, K., Ashby, C. R., & Kawahara, R. (2006). Correlation between plasma levels of glutamate, alanine and serine with severity of depression. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 30(6), 1155-1158.

 

Moseley, G.L. (2007) Reconceptualising pain according to modern pain science. Physical Therapy Reviews, 12(3): 169-178.

Norman, G. J., Karelina, K., Morris, J. S., Zhang, N., Cochran, M., & DeVries, A. C. (2010). Social interaction prevents the development of depressive-like behavior post nerve injury in mice: a potential role for oxytocin. Psychosomatic medicine, 72(6), 519-526.

Nicholas, M. K., Linton, S. J., Watson, P. J., Main, C. J. (2011) Early identification and management of psychological risk factors (“yellow flags”) in patients with low back pain: a reappraisal. Physical Therapy, 91 (5): 737-753.

O’Connor JC, André C, Wang Y, Lawson MA, Szegedi SS, Lestage J, Castanon N, Kelley KW, and Dantzer R

(2009) Interferon-γ and tumor necrosis factor-α mediate the upregulation of indoleamine 2,3-dioxygenase and the induction of depressive-like behavior in mice in response to bacillus Calmette-Guerin. J Neurosci 29:4200–4209.

Raison, C.L., Woolwine, B.J., Demetrashvili, M.F., Borisov, A.S., Weinreib, R., Staab, J.P., Zajecka, J.M., Bruno, C.J., Henderson, M.A., Reinus, J.F. and Evans, D.L., 2007. Paroxetine for prevention of depressive symptoms induced by interferon‐alpha and ribavirin for hepatitis C. Alimentary pharmacology & therapeutics, 25(10), 1163-1174.

Strike, P.C., Wardle, J. and Steptoe, A., 2004. Mild acute inflammatory stimulation induces transient negative mood. Journal of psychosomatic research, 57(2), 189-194.

Üçeyler, N., Valenza, R., Stock, M., Schedel, R., Sprotte, G., & Sommer, C. (2006). Reduced levels of antiinflammatory cytokines in patients with chronic widespread pain. Arthritis & Rheumatology, 54(8), 2656-2664.

Walker, A.K., Kavelaars, A., Heijnen, C.J. and Dantzer, R., 2014. Neuroinflammation and comorbidity of pain and depression. Pharmacological reviews, 66(1), 80-101.

 

Watson, P., Kendall, N. (2000) Assessing psychosocial yellow flags. Topical issues in pain, 2: 111-129.

Wright, C.E., Strike, P.C., Brydon, L. and Steptoe, A., 2005. Acute inflammation and negative mood: mediation by cytokine activation. Brain, behavior, and immunity, 19(4), 345-350.

Mindfulness and Chronic Low Back Pain; Why and How To.

Written by Kieran Macphail on . Posted in Acute Low Back Pain, Corrective Holistic Exercise Kinesiology, For Diet and Lifestyle Professionals, For Everyone!, For Health Professionals, For Movement Therapists, Low back pain, Mindfulness, Nutritional therapy, Orthopaedic Medicine, Sacro-iliac joint

Mindfulness is basically the western term for meditation. The practice has moved from weird hippies only, to being used by CEOs and professional sport, and is now being studied fairly extensively. This blog will focus on the relevance of mindfulness to chronic low back pain. Outlining the benefits and how to start a mindfulness practice.

Psychological stress can directly influence the musculoskeletal, endocrine, immune and nervous systems through the limbic system modifying chronic pain (Macphail 2014). Psychosocial risk factors for low back pain (LBP) chronicity are well known to lead to worse outcomes (Grimmer-Sommer 2008). Indeed the assessment of psychosocial factors is included in most guidelines for the management of LBP worldwide (Koes et al. 2010). Childhood abuse is associated with an increase in peripheralising of low back pain later in life (Leisner et al. 2014) suggesting psychological processes can modify the pain experience even later in life.

Cherkin et al. (2017) conducted an interviewer blinded, randomized controlled trial comparing mindfulness based stress reduction (MBSR), cognitive behavioural therapy (CBT) and usual care in 342 chronic low back pain (CLBP) patients aged 20-70. MBSR and CBT were both delivered as eight weekly two hour group sessions. Treatment effects were seen at 26 months and 2 year follow up. At 1 year and 2 years, Roland Morris Disability Questionnaire (RMDQ) scores were similar between groups. At 2 year follow 55.4% of the mindfulness group had clinically significant improvements in RMDQ and 41.2% in pain bothersomeness. In contrast usual care produced 42% and 31.1% of patients with clinicially significant improvements respectively, and CBT 62% and 39.6%. Follow-up rates were 78% for MBSR, 75% for CBT, and 89% for usual care. This may reflect lack of adherence to MBSR and CBT compared with usual care, but among those who did respond it appears the MBSR produced the greatest percentage of people with improvements in pain bothersomeness and it outperformed usual care on RMDQ. These results are startling given the limitations of the intervention, only eight two-hour sessions over eight weeks. The 8-week MBSR programme has also been shown to outperform the 10-steps to health aging programme in 282 community dwelling adults with CLBP (Morone et al. 2016). Thus there clearly seems to be benefit for mindfulness in patients with CLBP. So how do you or your patients get started with mindfulness?

Whilst the evidence discussed above strongly suggests some benefit from mindfulness interventions they can be very difficult to deliver. Therapists need to be confident in their value to be able to “sell” it to patients. Personal experience of the benefit is particularly valuable. In addition there will likely be personal benefit to the therapist.

The sequence of progression below is based on the mindfulness based stress reduction courses, with this authors own tweaks to make it easier to fit in to everyday life. In my experience its much easier to start with what personal development speaker Tony Robbins calls NET time, no extra time, activities. For example the first stage is doing one task each day mindfully.

 

1. One task daily done mindfully

e.g. brushing your teeth

2. Add one meal a day eaten mindfully

3. 5-10 minutes walking meditation

e.g. as part of your walk in to or out of work

4. 10-30 minutes mindful stretching

5. 10-30 minutes body scan done each day mindfully

6. 10-30 minutes seated meditation

 

From the very limited research we have in this area it appears seated meditation for about 30 minutes five times a week should be our goal with patients. This is very generic and non-specific. In reality we should look to help our patients develop a mindfulness practice that works for them, their personality and their schedule.

Establish if the patient has any experience of meditating. If not explain to them that mindfulness is being in the moment, the present. Often this is considered being in a “flow” state or in the zone. Flow occurs when our perceived ability meets the perceived demands of an activity. Much more on this can be gleaned by reading Flow by Mihaly Csikszentmihalyi who popularised this concept. Very simply anxiety occurs when we focus on the future and depression when focus on the past. Positive emotions like gratitude occur when looking in the past, and excitement when looking to the future. So the purpose is not to forgo looking forward or back but to develop an ability to be in the moment and to take ourselves back to the present when we find ourselves in a negative state.

With all these tasks its important to try. Some days will be tougher, the mind will be all over the place and concentration will be poorer. Other days a lot of negative thoughts may arise. There are real benefits though to being able to become aware of the fact that you cannot find the time to meditate, or you were so busy you got distracted and forgot or just could not fit it in. Becoming aware of this is the first step and then you can work improving the factors that lead you to miss sessions.

 

One task done mindfully daily

To start with pick a simple task that is done every day. The task I recommend is brushing teeth as we do this twice a day, it last about two minutes, and is very low concentration. It’s handy to pick a task you do multiple times a day so that if you miss it once you still have another opportunity. Other tasks, like ironing, washing up or even showering can be used. The key is that the patient will try to do this task mindfully. Instruct them just to focus on sensory cues in the moment. Breathing, tastes, smells, the feeling of the tooth brush on the teeth, their feet on the floor, any cues that bring them in to present and take them away from “monkey mind” thoughts in the past or present.

 

Eat one meal mindfully daily

The next progression is to eat a meal mindfully each day. The great thing with this task is you likely have three opportunities so if you miss one, then you’ve still got two opportunities. You can do this while eating with other people but it’s much tougher as it’s very easy to get in to conversation and being mindful in conversation is tricky. So to start focus on doing this activity during meals you are eating alone, even a snack if necessary.

Just focus on your breathing, the food, the tastes the smells. You will get distracted, just bring your mind back to a cue in the present each time, e.g. the smell, the tastes of the food, the feeling of your feet on the floor.

 

Walking meditation

This is another task that takes no extra time and is usually quite easy to get buy in from clients. As with the others the application is challenging but clients usually report acute benefit. Discuss the patient’s typical schedule with them and find a walk of around ten minutes they do most days. Often this is best to do on the way to work so they turn up to work in a good mindful state. If they don’t have an obvious way to fit this in to their schedule currently they can be encouraged to park 10 minutes further away from work or to go out for a short walk.

During the walk the client should focus on the steps and the sensory experience. Go through it once with them if possible and see which cues they prefer. Focusing on breathing in for four steps, pause for one, out for four. This can be adjusted to 3-1-3 if this suits the patient better. Just feeling the sensations in the feet and keep the walk as even as possible, maintaining a steady flow to the walk.

 

Mindful stretching

Mindful stretches is the first time we ask a patient to set aside extra time for their mindfulness practice. Many patients may never reach this point. The key here is that for a task to be done mindfully it needs to be very easy, unlike a true flow state, when mindful we are doing something very easy for us and being completely present. Thus it’s important the client is very comfortable with all stretches chosen and that none carry an injury risk.

Thus positions like sitting cross-legged, hands and knees, quad stretching in side lying, hamstring stretching in sitting and gentle trunk rotation may be useful. The stretches need to be tailored to the individual so that they are comfortable with them and for optimum efficiency they should also help mechanically.

 

Body scan

A body scan is a good transition from stretching to relaxation before fully transitioning towards a traditional meditative practice.

To start a body scan the patient should find a comfortable position. Common positions are lying down with a pillow for the head, or seated in a chair, on the floor or bed cross-legged with pillows under the hips and knees as needed.

The patient should start by focusing on their breath and settling in to relaxed diaphragmatic breathing. After a minute of settling in to this, the patient should begin getting an overall feel for the tension throughout the body. Then sequentially work down from the head, down the arms, the shoulders trunk and down the legs. In each area 3-5 breaths can be used to get an awareness of the tension in that area specifically and become aware of any sensations or emotions attached. Then 3-5 breaths can be used to relax to let go of the tension in the area.

The patient should be made aware that some areas will be easier than others. Thoughts will come in to the mind, just return to the breath and focus on becoming aware of the tension and feelings in an area and then letting it go.

 

Seated meditation

Seated meditation is our goal for most patients. With the aim of 30 minutes five times a week appearing to have significant anti-inflammatory effects.

By this stage patients should be comfortable at this point with the basics of mindfulness practice. Patients can be encouraged to;

  • Listen to guided meditations
  • Use various apps. My experience is that patients adhere to headspace for a few weeks and a few have stuck with it long term.
  • Progress through a sequence of focusing on the body, then the breath, then sounds and then thoughts.
  • Listening to meditative music, such as Anugama.
  • Using mantras, such as breathing in with a “yang” phrase such as strength or discipline and then a “yin” word on the exhalation such as humility or grace.
  • Progress from focusing on the breath, to areas of discomfort and then trying to focus on these areas on the inhalation and let go of the discomfort on the exhalation.

By the time the patient reaches this stage they will likely have their own thoughts on how they want to develop their practice. Walking meditation, mindfulness during a meal and a couple of daily tasks may be a really useful practice for one. Whilst another may do well with a daily mindful stretching programme. The practice should not be a means to an end in and of itself but should give the patient tangible benefits and if they are not seeing this it should be modified.

 

 

If this article has been useful at all please feel free to donate to help with the running of the site. Donations of £1 are really appreciated and help me keep the site add free, many thanks.





Physiotherapy Management of Chronic Low Back Pain Patients With Yellow Flags: A Systematic Review (Abstract, Discussion & Conclusion)

Written by Kieran Macphail on . Posted in For Health Professionals, For Movement Therapists, Low back pain

Abstract

 

CLBP is the leading cause of disability worldwide and patients with yellow flags have the worst outcomes and contribute significantly to the societal cost. Clinicians are aware of the importance of yellow flags but feel undertrained to deal with them. Furthermore there is a lack of clarity for clinicians looking at how to specifically manage these patients from guidelines and an incredibly varied set of approaches available to clinicians. The objective of this review was to establish the effectiveness of physiotherapy interventions for chronic low back pain patients with yellow flags. Three approaches were used for retrieving literature. Searches were conducted initially using the terms “physiotherapy”, “chronic low back pain”, psychosocial and “management or treatment”, using the databases PubMed, Embase, PEDro and CINHAL from January 1987 up to February 2017. In addition content experts were consulted to ensure no additional papers were missed and citation tracking was implemented. 39 studies were identified with 20 meeting the selection criteria. Interestingly the term yellow flags is not used in the treatment literature and specific psychosocial terms are used. This review suggests specific exercise and passive interventions are more beneficial for reducing measures of pain, whilst psychological input and general exercise are more targeted towards psychosocial measures.

Discussion

 

Given the significant nature of the problem of chronic low back pain it is surprising only 20 studies met the inclusion criteria. These studies show a consistent pattern that a variety of interventions are able to decrease psychosocial symptoms, improve function and decrease perceived pain. Disappointingly none of the research on the popular Maitland and McKenzie approaches met the inclusion criteria. Of the studies included the reporting of how interventions were carried out is often not sufficient to allow reproducibility or use in practice, with limited details on sets, repetitions, tempo and progressive overload of exercises across all studies.

Of all the studies those using the CFT approach had the most positive effects as measured by disability and pain. The other particularly effective approach was the walking programme of Hurley and colleagues (2015) which had the same effect as their exercise group and usual physiotherapy interventions for pain, disability and psychosocial measures but the walking programme had greater adherence and lower costs. This fits with some of the emerging research in whiplash pain which suggests a low cost telephone based intervention was equal to a more expensive and time intensive motor control intervention (Michaelef et al. 2014).

A general theme emerging across the studies was the benefits to pain of more specific exercise programmes and the benefits to psychosocial factors through general exercise and psychological input. The admittedly very limited selection of two studies (Weiner et al. 2003, 2008) suggests that whilst passive interventions could positively affect pain, the addition of general conditioning was required to reduce fear avoidance. Similarly, Vincent et al. (2014) found that the lumbar extensor strengthening was sufficient to increase physical function but the total body programme was required to improve perceived disability and psychosocial measures. Supporting this Geisser et al. (2015) found specific exercise and manual therapy reduce pain whilst their general exercise group had reduced disability.

Improvements in fear avoidance beliefs are often associated with improved function (Crombez et al. 1999) nonetheless in these studies it appears that active treatment such as walking or whole body exercise is required to improve psychosocial measures. There were only two education-based studies but the positive results suggest pain acceptance and neurophysiology education in combination should be useful. The results from intensive functional restoration and CBT programmes suggests these kind of multidisciplinary programmes are effective across all measures, with Pfingsten and Hilderbrandt (2001) noting the importance of work hardening in promoting return to work.

The classification based approaches such as Macedo et al. (2014) suggest that there could be future developments allowing clinicians to classify which patients respond best to general exercise and to more general exercise based approaches. In particular patients classified as dysfunctional on the multidimensional pain inventory have been shown to respond best to combined psychosocial and physical input (Riipen et al. 2015).

 

Conclusion

Considering that CLBP is the leading cause of disability worldwide and those with yellow flags are known to suffer the worst and contribute most to societal cost it is surprising how few studies met the selection criteria. This review has shown that whilst the term yellow flags are used in the assessment literature and guidelines, the term psychosocial and the factors that make it up are used in the treatment literature. The studies selected highlight that passive, active; more comprehensive and simple education interventions can all positively impact the pain experience of this patient group. While passive interventions can improve pain, more whole body active approaches such as whole body weight training or walking may be necessary to positively impact the psychosocial aspects. Comprehensive CBT and functional restorations are effective but the inclusion of work hardening may significantly aid in return to work. Pain education approaches involving pain neurophysiology education and pain acceptance were both effective compared with more traditional back school and pain avoidance approaches respectively. A combination of these may be useful clinically. The CFT approach was the most effective in terms of disability and self reported pain. This review suggests specific exercise and passive interventions are more beneficial for reducing measures of pain, whilst psychological input and general exercise are more targeted towards psychosocial measures.

References

On request! kieran@kieranmacphail.com

Review: Chronic Low Back Pain And Yellow Flags, What Treatments Are Effective?

Written by Kieran Macphail on . Posted in Corrective Holistic Exercise Kinesiology, For Health Professionals, For Movement Therapists, Low back pain, Orthopaedic Medicine

1. Introduction

 

Low back pain (LBP) is usually defined as pain localised below the costal margin (ribs) and above the inferior gluteal folds (buttock crease). It is the leading cause of disability worldwide and is becoming increasingly prevalent (Harkness et al. 2005, Hoy et al. 2012, Vos et al. 2012). Chronic low back pain (CLBP) is variously defined as lasting longer than 7-12 weeks, to 3 months (Anderrson 1999, Frymoyer 1988). LBP is typically classified as “specific” or “non-specific”. Specific LBP refers to symptoms caused by specific pathophysiologic causes, such as hernia nucleus, infection, inflammatory disease, osteoporosis, rheumatoid arthritis, fracture or tumour (Van Tulder and Koes 2010). There is no effective cure for non-specific low back pain (NSCLBP) (Van Middelkoop et al. 2011) and this represents the 90% of the LBP population that cannot be classified as specific LBP (Deyo et al. 1992). Most guidelines are based on the assumption that symptoms resolve spontaneously and that return to work equals recovery (Anderrson 1999, Van Tulder et al. 2006). However, when pain is assessed it appears patients may be returning to work despite their pain (Bowey-Morris 2011), and whilst spontaneous recovery occurs in approximately a third of patients after 3 months, 71% still have pain after 1 year (Itz et al. 2013).

CLBP patients with psychosocial, psychological and social, risk factors are known to have poorer outcomes and increased management costs (Grimmer-Somers 2006, Nicholas et al. 2011). The term “yellow flags” was originally used to describe psychosocial risk factors that predict disability in LBP patients (Kendall et al. 1999). These risk factors are predictors of return to work and disability in CLBP patients (Glattacker et al. 2013). The risk factors can be identified using a questionnaire or a clinical diagnosis (Watson and Kendall 2000). Questions cover beliefs that are associated with delayed return to work and disability. These include fears about pain, injury, recovery and being despondent or anxious. It is suggested that having a few strongly held negative beliefs or several weaker ones could be used to identify at risk patients (Nicholas et al. 2011). These beliefs increase a patient’s perception of threat and modern neuroscience suggests that pain is the conscious interpretation that tissue is in danger (Moseley 2007). These beliefs can be viewed as “thought viruses” (Butler and Moseley 2013). The term yellow flag has now been refined to encompass psychological factors that a physiotherapist could manage, whereas orange flags are now used for psychopathology, which requires specialist psychological management. Alternatively, when the yellow flag belief is positive, for example, an expectation that they will recover; it can be viewed as a positive “pink flag” (Gifford 2005). The more subjective components of the workplace such as perception are termed “blue flags”, and the more objective risk factors such as the nature of the work are termed “black flags” (Main et al. 2004).

2. Background

Yellow flags are now included in most LBP guidelines although there is wide variation in suggestions in how to assess and manage these patients (Koes et al. 2010). The New Zealand guidelines (National Health Committee 2004) suggest assessment with the acute low back screening tool and the Canadian guidelines are similarly specific (Rossignol et al. 2007), suggesting assessment at 4 weeks or straight away if chronic. However, the other guidelines are less specific in their assessment. The Australian, American, Dutch, French, German and United Kingdom guidelines suggest early assessment but are not specific about how to assess (Australian Acute Musculoskeletal Pain Guidelines Group 2003, Chou et al. 2007, The Dutch Institute for Healthcare Improvement (CBO) 2003, Agence Nationale d’Accreditation et d’Evaluation en Sante 2000, Drug Committee of the German Medical Society 2007, NHS 2008). Similarly, the Finnish and Norwegian guidelines list signs of “yellow flags” and are even more ambiguous on assessment (Malmivaara et al. 2008, Laerum et al. 2007). The European guidelines propose an initial assessment of “yellow flags” and then a review in detail if there is no progress in acute and sub acute low back pain (van Tulder et al. 2006) or assess initially in chronic patients (Airaksinen et al. 2006). In contrast the Italian guidelines recommend assessing psychosocial factors after 2 weeks (Negrini et a 2006) and after 2-6 weeks is suggested in the Spanish guidelines (Spain, the Spanish Back Pain Research Network 2005). The Austrian guidelines are less specific and they suggest patients who do not progress over time should be assessed (Friedrich and Likar 2007). In treatment patients with yellow flags are not specifically addressed but all guidelines at least briefly state the need for re-assurance and return to normal activities, which may aid yellow flag management. The European guidelines suggest the inclusion of a cognitive behavioural approach and the German guidelines suggest psychotherapy may be an education option for referral for multi-disciplinary treatment. Thus within the guidelines the importance of yellow flags is appreciated in assessment and for triage but there is ambiguity in the specifics of management.

The differences seen across the full range of physiotherapy approaches is far greater than within the guidelines. Within physiotherapy there are many different approaches to managing these patients as shown in table 2.1.

Table 2.1 Matrix of different Physiotherapy Approaches

Hands on   Hands off
More focused on the local tissue Maitland (2013), Society of Musculoskeletal Medicine (Atkins et al. 2010) McKenzie (McKenzie and May 2003) McGill (2007),Sahrmann (2002)
  Lee/ Vleeming (2001), O’Sullivan (Fersum et al. 2009)
More focused on central processes Dorko (2003) Neuro-developmental (Kolar et al. 2014) NOI/ Mind body group (Butler and Moseley 2013)

 

 

The Maitland and McKenzie approaches are the most utilised in the UK (Foster et al. 1999). These approaches and the traditional orthopaedic medicine approach (Atkins et al. 2010) are perhaps the most bio-medical focused, placing emphasis on finding and treating the tissues that is the cause. Other approaches such as that derived by O’Sullivan (Fersum et al. 2009) and, Lee and Vleeming (Lee 2001) attempt to classify patients that need more psychosocial input. With the new clinical model 4, the Society of Musculoskeletal Medicine is moving in the same direction (Atkins et al. In Press). The Neuro Orthopaedic Institute and Mind In Body groups place the most emphasis on a hands-off approach to psychosocial aspects (Butler and Moseley 2013). This approach is based on an understanding of the importance a patient’s perception has on their symptoms and thus the benefits of education and a graded return to normal activities. In contrast Dorko (2003) is a proponent of a hands-on approach to addressing the psychosocial aspects. Clinicians are aware of the importance of psychosocial factors in these patients (Scheermesser at al. 2012) but feel underprepared and may sometimes stigmatise these patients (Synnott et al. 2015). Thus whilst yellow flags are clearly important there remains a lack of clarity for clinicians looking at how to specifically manage these patients from guidelines and clinicians are using an incredibly varied set of approaches. This study aims to investigate how and why different physiotherapists choose to use the different approaches.


3. Literature Review

The literature review was undertaken with grounded theory in mind. The aim was to get an overview of the various different methods currently used in practice to provide context for the interviews. Issues around clinical reasoning and motivation to practice to were not reviewed so that the exploration of these areas would be more inductive.

 

3.1 Search strategy

Three approaches were used for retrieving literature. Searches were conducted initially using the terms yellow flags and low back pain, and treatment, or assessment, or management, using the databases PubMed, Embase, PEDro and CINHAL up to September 2015. This however did not identify any papers and it became clear that whilst the term yellow flags is used in the assessment literature it is not used in treatment papers. As such the searches were repeated using the term psychosocial and low back pain, and treatment, or assessment, or management. In addition content experts were consulted to ensure no additional papers were missed and citation tracking was implemented. No time limit was set for papers and foreign language papers that were identified using the English terms were included. Refworks was used to store and remove duplicates from the searches.

 

3.2 Selection of studies

The student researcher, KM, initially screened the title and abstract of the identified studies. The full text was then analysed. Studies were selected on the basis of the following selection criteria;

  1. Primary experimental design study of human participants with chronic (>12weeks) or recurrent (repeated episodes over 12 months) low back pain
  2. Participants must have yellow flags or measured psychosocial status commensurate with yellow flags
  3. Studies must cover the management of patients

Studies were excluded if;

1. The intervention group did not have yellow flags or measurable psychosocial factors

2. Looked at post surgical patients

3. Mixed groups of sub-acute and chronic patients

4. Mixed groups of neck and CLBP patients

5. The intervention was purely psychological (CBT) and outside the scope of traditional physiotherapy practice

 

3.3 Data management

Risk of bias was assessed as suggested by the Cochrane Back Review Group (Bendix et al. 1996) as shown in table 4.1. Studies with a score above 6 were considered low risk of bias. Studies with a score below 6 were considered high risk. Where any doubt remained an author of the study was contacted via email.

Table 3.1 Criteria for risk of bias analysis

1 Was the method of randomisation adequate?
2 Was the treatment allocation concealed?Was knowledge of the allocated interventions adequately prevented during the study?
3 Was the patient blinded to the intervention?
4 Was the care provider blinded to the intervention?
5 Was the outcome assessor blinded to the intervention?Were incomplete outcome data adequately addressed?
6 Was the drop-out rate described and acceptable?
7 Were all randomised participants analysed in the group to which they were allocated?
8 Are reports of the study free of suggestion of selective outcome reporting?Other sources of potential bias:
9 Were the groups similar at baseline regarding the most important prognostic indicators?
10 Were co-interventions avoided or similar?
11 Was the compliance acceptable in all groups?
12 Were the timing of the outcome assessment similar in all groups?

 

3.4 Search Results

In total 367 studies were identified, after screening titles and abstracts 11 remained. All 11 papers met the inclusion criteria. One foreign language paper met the inclusion criteria was included (Pfingsten and Hilderbrandt 2001), this paper was translated using google translate so that it could be included in the analysis. One paper (Bergstrom et al. 2012) was excluded as it included both neck and back patients in one homogenous group with no separate analysis of back pain patients. A clear limitation is that these studies look at groups of CLBP patients that show yellow flags on average, but within each cohort there will have likely been patients with very few yellow flags and possibly some with very significant yellow flags. Using table 4.1 of the Cochrane Back Review Group (Bendix et al. 1996) the studies were classified as high or low risk. One paper was high risk (Pfingsten and Hilderbrandt 2001) and nine were classified as low risk. The oldest trial that met the selection criteria was Alantra et al. (1994) as despite it’s age it met all quality criteria for selection. The 10 studies all looked at patients of 18 years or older with CLBP, using at least 6 months follow up. All but three were randomised controlled trials, with two being cohort studies (Pfingsten and Hilderbrandt 2001, O’Sullivan et al. 2015) and another with no randomisation (Vowles et al. 2007).

 


Figure 4.1 Flow diagram of literature review

3.5 Findings

The studies identified cover a broad spectrum of biopsychosocial interventions, with some focusing on more biomedical interventions, psychosocial interventions or a combination. Six studies looked at a predominantly biomedical approach.

3.5.1 Biomedical approaches: Passive approaches

Two studies with a low risk of bias from the same group have examined a passive biomedical intervention. Weiner et al. (2003, 2008) conducted randomised controlled trials of percutaneous electrical nerve stimulation (PENS). This involves delivering a low voltage electrical current through a specially designed needle to the adipose layer close to the nerves near the site of pain. In both studies patients were aged 65 or older, lived in the community and experienced moderate CLBP almost every day for more than 3-months. In their earlier study (Weiner et al. 2003) the authors measured psychosocial factors with the Geriatric Depression Scale and the mean score was 6.81, which equates to mild depression, indicative of yellow flags. In their later study (Weiner et al. 2008) psychosocial function measures showed mild to moderate levels of psychosocial stress across the Geriatric Depression Scale, the Chronic Pain Self-Efficacy Scale, the Catastrophizing Scale of the Cognitive Strategies Questionnaire and the Fear-Avoidance Beliefs Questionnaire. The combination of the scores across these measures shows these patients had yellow flags.

In their earlier study subjects were randomised to receive 6-weeks of twice weekly PENS and physical therapy or sham PENS stimulation and physical therapy (Weiner et al. 2003). The PENS and physical therapy group had significant reductions in pain intensity and pain related disability, the sham PENS and physical therapy group did not. These improvements remained at 3-month follow up. Furthermore, significant improvements in sit to stand, psychosocial function and lifting endurance were also seen in the PENS and physical therapy group. In their later study (Weiner et al. 2008) they had 200 participants, randomised to receive either PENS, brief PENS to control for treatment expectancy, PENS with general conditioning or brief PENS and general conditioning. All interventions were done twice a week for 6 weeks. The general conditioning consisted of up to 30-minutes walking and a further nine motor control exercises for 2-minutes each with 1-minute rest. This was accompanied by a home exercise programme of 12 stretches to be done for 3 repetitions, 3 times a day, and 30 minutes of additional walking above normal activity levels. After the 6-week intervention all four groups produced statistically significant improvements in present, average and greatest pain intensity measured on the short form McGill Pain Questionnaire. Interestingly the brief PENS of 5-minutes produced an equal improvement to that of the 30-minute PENS. Furthermore, the general conditioning protocol had no additional benefit on pain measures above that of the PENS interventions, however it did significantly improve fear avoidance in comparison to PENS. These studies suggest that whilst sham PENS is ineffective, 5-minutes is sufficient to have treatment effect, casting significant doubt over the authors proposed mechanism of effect and suggesting the effects may be more centrally driven. Furthermore they indicate the potential benefits of active interventions, in particular general conditioning, on fear avoidance beliefs.

 

3.5.2 Biomedical approaches: Exercise-based interventions

Four of the studies examined exercise-based interventions. Murtezani et al. (2011) found high intensity aerobic exercise outperformed a passive electrotherapy group not dissimilar to the approach of Weiner and colleagues. They randomised 101 patients to either a high intensity aerobic exercise group or a passive modalities group. They used the Hospital Anxiety and Depression Scale to measure psychosocial factors. The scores suggest the patient’s as a group were indicative of patients with yellow flags. The active group produced a 3.9 mean decrease in the visual analogue scale. Interestingly the control group produced no improvements in pain intensity, toe touch, anxiety and depression scores and disability. Suggesting the passive intervention was far less effective than that the results seen in Weiner and colleague’s studies (2003, 2008). Nonetheless the high intensity aerobic exercise intervention produced improvements across all these measures.

In contrast the other two low risk of bias studies looking low intensity aerobic interventions found no significant difference between their intervention and control groups. Hurley et al (2015) conducted a 3-arm assessor blind RCT of an individualised walking programme, an exercise group intervention and usual care physiotherapy, in 246 patients aged 18-62 with CLBP. Participants were recruited from those seeking help at the local hospital and this was used as a baseline as opposed to trials from the general population, which require a baseline pain score for inclusion. The psychosocial baseline assessment of these patients suggests as a group they were representative of patients with yellow flags. The walking programme was individualised and education on functional restoration and addressing fears around movement and the patient’s understanding of their problem were addressed. Patients were given a pedometer to measure their initial activity. From then on they had weekly contact with a physiotherapist, with the aim to progress them to 30-minutes total daily walking 5 times a week. This is in line with the recommendations of the American College of Sports Medicine and previous studies (Garber et al 2011, Tully et al. 2005, 2007). The exercise group attended a class based on the back to fitness programme (Moffett and Frost 2000) endorsed by the UK National Institute of Clinical Excellence guidelines, once per week for eight consecutive weeks. The physiotherapists providing the usual physiotherapy were free to prescribe education, advice, manipulation and exercise as usual but could not refer patients to an exercise group or a walking programme. Similarly, Mannion et al. (1999) compared modern active physiotherapy, muscle reconditioning on training devices, and low-impact aerobics, each done twice a week over 3-months. Modern active physiotherapy was considered to be 30 minutes of individual therapy focused on improving functional capacity and instructions on ergonomic principles. This involved isometric exercises, Theraband exercises and use of general-strength training devices. In addition patients were given home exercises and encouraged to perform them. As is quite typical in many studies the specifics of what was actually done in terms of exercises and all acute variables remains a mystery. Muscle reconditioning involved 12-weeks on the David Back Clinic programme in groups of two to three, which uses progressive isoinertial strengthening in all three planes of motion in a patient’s pain free range of motion. Sessions are proceed by a 5-10 minute cycling or stepping warm up, and relaxation and further undefined strengthening exercises were done between isoinertial exercises. The aerobics and stretching class consisted of a class with 12 people maximum, lasting 1-hour done to music. The initial 20 minutes was used for static stretching and low intensity whole body aerobic exercise. This was followed by 30 minutes of exercises targeted primarily at the legs and trunk. The last 15 minutes was used for cool down and relaxation. 148 participants met the inclusion criteria and 16, 10.8%, dropped out during the study. The three groups did not differ significantly in terms of compliance with 84.1% completing all 24 sessions. Interestingly in both studies all interventions were equally efficacious, despite all three interventions targeting different aspects of physical conditioning. Mannion et al. (1999) suggest this shows that the mechanism of benefit may be more central and possibly due to challenging beliefs around physical activity and chronic low back pain. This is further supported by the correlation between improvement in fear avoidance beliefs and self rated disability. Furthermore these correlations were also present in the devices and aerobics group where these effects were still seen at 6-months, but not in the active physiotherapy group where they were not seen. There were also improvements in spinal flexion and these improvements were correlated with improvements in pain and intensity and self-rated disability. Hurley et al. (2015) highlight that whilst there was no difference in outcomes, the walking programme had the greatest adherence and the lowest costs.

Vincent et al. (2014) compared total body resistance training with lumbar extensor training and a control group in obese individuals. Resistance training sessions were carried out three times a week for 4-months. The total body training group did one set of 12 exercises, for 15 repetitions at 60% of repetition maximum, with 60 seconds rest between sets. Load was increased approximately 2% every week to maintain a BORG perceived exertion from 16-18. The lumbar extension group did just the lumbar extension exercise from the total body resistance-training group. For the first week they did two sets once a week and after that they did one set once a week with same acute variables as the total body group. As is typical in these studies no information on the tempo of the exercises was provided. The control group received advice on healthy nutrition via leaflet from the American Heart Association, information about back pain and information on bodyweight back strengthening exercises. The total body training group had greater reductions in self-reported disability as measured on the Oswestry Disability Index and Roland Morris Disability Questionnaire. Pain Catastrophizing Scale scores decreased in the total body training group more than in the control group at age 4-months. Lumbar extensor training and total body training both decreased walking and chair rise pain severity significantly more than the control. From this it is tempting to imply that the lumbar extensor training was sufficient to improve physical function whilst the total body training provided additional benefits to perceived disability and psychosocial factors.

 

3.5.3 Psychosocial approaches: Pain education

Five studies looked at more directly addressing the psychosocial component of patient’s pain experiences, two of which looked specifically at the effects of pain education and were considered low risk of bias. Moseley and colleagues (2004) conducted a randomised controlled trial comparing pain neurophysiology education with traditional back school education. Each subject took part in a 3-hour 1:1 education session, which included a 20-minute break for a drink. Diagrams and hypothetical examples were used to convey ideas. The experimental neurophysiology education focused on the functional significance of the nervous system, nociception, synapses and how chemicals talk to each other, and the plasticity of the nervous system including peripheral and central sensitisation and movement control. The control group received more typical back education. This covered the anatomy of the spine including the vertebrae, intervertebral discs, trunk and back muscles, normal spinal curves, posture and movement. This included analysis of lifting technique in terms of joint forces and intradiscal pressures, lifting techniques loads and ergonomic advice, as well as advice on stretching, strengthening, endurance and fitness. No information on the nervous system was included. At the end of the session participants were given a 10 section workbook and asked to complete one section a day, each week day for 2-weeks, and then asked to answer the three questions at the end of each section. Subjects returned for assessment 15-week days after the initial assessment. This resulted in significant improvements in pain attitudes, pain catastrophizing scale, straight leg raise and forward bend. Roland Morris Disability Questionnaire was statistically significantly improved although the authors suggest this probably was not a clinically significant improvement. Thus suggesting significant benefits in nervous system based education

Vowles et al. (2007) looked at the effect of pain acceptance, pain control and continued practice instruction strategies on physical impairment, in 74 unemployed individuals on workers compensation with LBP for greater than 3 months. Participants were sent a Beck Depression Inventory, Fear of Pain Questionnaire Short-Form, Pain Anxiety Symptoms Scale-20, McGill Pain Short Form Questionnaire, Chronic Pain Acceptance Questionnaire and the Physical Impairment Index to complete before attending their appointment. The Physical Impairment Index involves seven standardised physical tests; spinal tenderness, a 10 seconds hold of both feet 6 inches off the floor in supine, a 10 seconds hold of both shoulders 6 inches off the floor in supine, total flexion, total extension, total side flexion and passive straight leg raise. After each task patients were asked to rate their pain on a scale of 0-10. These scores were added to create a composite pain score. The instructions for the first test were the same for all participants. For the second test participants were randomised in to three different groups, pain control, pain acceptance and continued practice. The pain control group instructions emphasised that it was possible to control pain through mental strategies or efforts and asked patients to prevent pain during tasks. The pain acceptance group instructions emphasised that pain did not need to influence activity and asked participants not to let pain influence their performance. The continued practice group were asked to continue as they had before, and were informed that improvements can occur with practice. At Baseline the acceptance group had significantly higher levels of physical impairment than the continued practice group. There was no significant difference with the pain control group. After the intervention the pain acceptance group reduced their scores by 16.3%, whilst there was a worsening of 8.3% in the pain control group and 2.5% reduction in the continued practice group. Interestingly there was no significant difference across groups in terms of pain during the tasks. This suggests that the pain acceptance strategy allowed the patients to improve their physical performance without any increase in pain. Conversely it suggests the pain control group had increased physical impairment with no improvement in pain. The authors note that 124 people in total were asked to start the trial and only 91 started. They state that authors experience suggested that the patients that refused to take part were afraid of exacerbating their symptoms. This skews the population of the study towards those who were more likely to do well with this intervention. Nonetheless it provides what appears to be an immediately useful approach for clinicians to use in explaining how to approach pain during exercise and activities of daily living. The combination of pain acceptance with pain neurophysiology education may prove even more advantageous but this remains to be seen.

 

3.5.4 Psychosocial approaches: Intensive cognitive behavioural therapy and functional restoration programmes

Three studies looked at what could be considered intensive rehabilitation programmes, with functional restoration and CBT components. Pfingsten and Hilderbrandt (2001) reported on the results of the functional restoration programme which they trialled over 10 years with 762 CLBP patients, from 1990 to 2000. This was lowest quality study of those identified, with no randomisation, blinding and no explanation of drop outs. Nonetheless, studies such as this provide inform us of methods utilised with this patient group. As expected patients who were off work had increased psychosocial and pain symptoms compared with working patients. Their programme consisted of a 3 week pre-programme of education, stretching and bodyweight exercises followed by an intensive 7 hours a day outpatient programme for 5 weeks. This involved aerobic, functional strength and endurance exercises, back school education, cognitive behavioural group therapy, relaxation training and vocational counselling. The programme reduced Numerical Rating Scale, Pain Disability Index, Allgemiene Depressionsskala (amount of depression), psychological distress (Fear Avoidance Beliefs Questionnaire) and healthcare utilisation. Furthermore work capability significantly improved. However, when they modified it to remove the work hardening component there were no such improvements. These results remained stable at 12-month follow up.

Two studies with a low risk of bias using intensive psychosocial based physiotherapy interventions were identified (Alaranta et al. 1994 and Lee et al. 2013). Alaranta et al. (1994) looked at a combined psychosocial activation and physical intervention in CLBP compared with an inpatient rehabilitation programme in 152 patients, with a control group of 141. All patients had been referred to receive inpatient rehabilitation in Finland. Subjects were stratified according to sex and age and randomised to either group. Both interventions started 3-weeks after assessment and lasted 3-weeks. The intervention group received 37-hours of guided self-controlled physical exercises, without passive physical therapy and 5 hours of discussion groups a week, and individual consultations for work problems. The programme included a range of cardiovascular activities and games, strength and endurance training based off the patients 1 repetition maximum, stretching, relaxation and cognitive-behavioural disability management groups. This group did not receive any passive physiotherapy. The inpatient therapy involved a large amount of passive therapy as well as back education, pool exercises, indoor and outdoor activities. The authors considered this programme to be 40-50% of the intensity of the intervention group. The other study (Lee et al. 2013) directly assessed psychosocial treatment in CLBP patients aged 18-55, with Orebro Musculoskeletal Pain Questionnaire scores of 106-145 indicating moderate psychosocial risk factors. Patients were randomised to either an integrated work rehabilitation group or the conventional treatment group. Physiotherapists in this study had postgraduate qualifications and had received training in the cognitive behavioural approach. Patients received individual treatment for up to 3 months. Conventional treatment typically involved a combination of electrophysical agents, lumbar traction, manual therapy, and exercise therapy. Dictated by the patients’ symptoms at presentation and on their response to treatment. The cognitive behavioural approach group received an individualised graded activity programme, pacing techniques, work conditioning, return-to-work goal setting, self-management strategies, job analysis, and ergonomic advice. The aim was to improve their physical and functional capabilities with thorough attention to return to work. The researchers took the step of calling patients who missed an appointment to remind of them of their next appointment. Patients were discharged when they were able to return to work, had a subjective improvement of 70% or greater or they reached a plateau.

In both studies the authors suggest the results for the primary intervention group are clinically significant. Alaranta et al. (1994) found that at 3-months lateral trunk flexion, trunk rotation and hamstring flexibility was 11-12% increased in the combined group compared with 2-9% in the inpatient group. Abdominal, back and squatting strength improved significantly more in the intervention group in comparison to the inpatient group. These trends remained at 1-year follow up. The intervention group had greater decreases in pain at 3-month (17.1 vs 9.1) and 12-month (15.9 vs 8.9) follow up as measured using the Million index. Usage of physiotherapy and medical services was significantly decreased in both groups with the intervention group performing best. Mean days of sick leave per year decreased by 14 days in the intervention group, although this was not statistically superior to the inpatient group. At baseline to 3-months and at 12-month follow-up there were significant improvements in depression, subjective symptoms, aspects of personality, beliefs in disease and control and psychosocial adjustment in both groups. Similarly Lee et al. (2013) found that at discharge, the patients in the cognitive behavioural approach group made significant improvements in work recovery expectation, pain self-efficacy, and were more satisfied than the conventional treatment group.

 

3.5.5 Classification based approaches

Two trials with low risk of bias using a classification-based approach were identified (O’Sullivan et al. 2015 and Vibe Fersum et al. 2013). Both approaches used the Cognitive Functional Therapy (CFT) approach developed by O’Sullivan (Dankaerts and O’Sullivan 2011).

O’Sullivan et al. (2015) recruited 47 patients with at least a 1 year history of NSCLBP to a waiting list. 26 met all the selection criteria and underwent an initial 3-months on waiting list where they repeated the baseline assessments at 6-weekly intervals. The study did not have a control group, but went to extensive lengths to establish that participants had a stable condition and establish a clear baseline for the group. Based on the STarT Back screening tool scores, 14 patients were high risk, eight were moderate, and four were considered low risk. These scores indicate that these patients had yellow flags. They were then put through a cognitive functional therapy programme, which, focused on improving functional movements and postures, and tackling pain behaviours. In addition they took patients through cognitive reconceptualisation of their NSCLBP experience. Questioning of beliefs around pain, their relationship to pain, pain coping, and the relationship of stress with their pain were assessed. The primary outcomes were the Oswestry Disability Index and the Brief Pain Inventory, the average of four pain scores, maximum, minimum, average and current pain in the last 24 hours. An average of 7.7 treatments was conducted over 12 weeks. Oswestery Disability Index scores were 22 points lower after treatment, 23 points lower after 3 and 6 months and 24 points lower after 12 months. The initial reduction equates to a 54% reduction from baseline. Pain scores were 1.6 points lower after treatment, 1.5 and 1.6 points lower after 3 and 6 months and 1.7 points lower 12 months. All these results represented statistically significant reductions.

Vibe Fersum et al. (2013) unusually specified that participant’s pain was provoked and relieved by specific activities, movements or postures. The numerical rating scale needed to average at least 2/10 over the proceeding 14 days and the Oswestry Disability Index needed to be greater than 14%. The authors state the selection criteria designed this way to select patients whose movement behaviour had a clear association with their pain disorder. Patients with greater than 4 months sick leave were excluded on the grounds that they would require a specific return to work programme. 121 participants met the inclusion criteria and were randomised to receive either a cognitive behavioural functional therapy or manual therapy and exercise. The three physiotherapists delivering the approach were experienced exponents of using a multidimensional classification system. Based on the classification system each patient received a tailored intervention targeted at improving the cognitive, movement or lifestyle component the classification system suggested was maladaptive or provocative. The Oreboro Musculoskeletal Pain Questionnaire was also used to target psychosocial interventions. The intervention had four main components. For each patient their vicious cycle of pain was explained in a personalised diagram based on their assessment findings. Specific movement exercises designed to normalise their maladaptive movement behaviours were given based on their movement classification diagnosis. Functional restoration based on the movements they reported avoiding or provocative, and a physical activity programme tailored to the movement classification. The initial session was 1 hour and follow-ups were 30-45 minutes. Patients were initially seen once a week for 2-3 weeks and then progressed to follow-ups every 2-3 weeks over the course of the 12-week intervention. The comparison group received joint mobilisation or manipulation techniques to the spine or pelvis as delivered by specialists in orthopaedic manual therapy with an average of 25.7 years experience. These physiotherapists had no prior experience of the classification system or cognitive behavioural functional therapy. 82.5% of the patients received exercises based on the physiotherapists’ findings. Initial appointments in this group were 1 hour and follow-ups lasted 30 minutes. Both sets of therapists underwent a half-day of training with a clinical psychologist on the concepts of a best practice cognitive approach to managing back pain. Both groups received 8 sessions on average. Their primary outcome measures were pain was measured using the pain intensity rating scale and the Oswestry Disability Index. A validated 15-item scale to self-evaluate back specific function. There is some confusion over the pain scale used as the test suggests it was average pain over the proceeding two weeks, whilst the table reporting the data suggests it was one week. There was no difference in medication usage between groups before or after treatment. A lack of compliance withdrawal was set at 50%, leading to 27.1% of the manual therapy and exercise group, and 17.7% from the cognitive functional therapy group failing to complete treatment, which precluded an intention to treat analysis. After the intervention average pain over the last week decreased from 5.3 to 3.8 and stayed 3.8 at 12-month follow up, in the manual therapy group. In cognitive functional therapy group it went from 4.9 to 1.7, and crept back to 2.3 at 12-month follow up. The Oswestry Disability Index decreased from 24.0 to 18.5 after intervention and was 19.7 at 12-month follow up in the manual therapy and exercise group. In the cognitive functional therapy group it decreased from 21.3 to 7.6 and was 9.9 at 12-month follow up. These results were all statistically significant in favour of cognitive functional therapy over manual therapy and exercise. It is clear which intervention they were hoping to prove effective and it is possible that increased effort consciously or unconsciously may have gone in to the treatment group. Further the clinicians treating the control may well have been less invested in the outcome of the subjects they treated. This may account for the treatment group receiving 30-45 minutes for follow-ups compared to 30 minutes in the control group. Nonetheless the results are in keeping with those of O’Sullivan et al. (2015) highlighting the benefit of a classification-based approach.

3.6 Discussion

Given the significant nature of the problem of chronic low back pain it is surprising only 10 studies met the inclusion criteria. These studies show a consistent pattern that a variety of interventions are able to decrease psychosocial symptoms, improve function and decrease perceived pain. Disappointingly none of the research on the popular Maitland and McKenzie approaches met the inclusion criteria. Of the studies included the reporting of how interventions were carried out is often not sufficient to allow reproducibility or use in practice.

Of all the studies those using the CFT approach had the most positive effects as measured by disability and pain. The other particularly effective approach was the walking programme of Hurley and colleagues (2015) which had the same effect as their exercise group and usual physiotherapy interventions for pain, disability and psychosocial measures but the walking programme had greater adherence and lower costs. This fits with some of the emerging research in whiplash pain which suggests a low cost telephone based intervention was equal to a more expensive and time intensive motor control intervention (Michaelef et al. 2014).

The admittedly very limited selection of two studies (Weiner et al. 2003, 2008) suggests that whilst passive interventions could positively affect pain, the addition of general conditioning was required to reduce fear avoidance. Similarly, Vincent et al. (2014) found that the lumbar extensor strengthening was sufficient to increase physical function but the total body programme was required to improve perceived disability and psychosocial measures. Improvements in fear avoidance beliefs are often associated with improved function (Crombez et al. 1999) nonetheless in these studies it appears that active treatment such as walking or whole body exercise is required to improve psychosocial measures. There were only two education-based studies but the positive results suggest pain acceptance and neurophysiology education in combination should be useful. The results from intensive functional restoration and CBT programmes suggests these kind of multidisciplinary programmes are effective across all measures, with Pfingsten and Hilderbrandt (2001) noting the importance of work hardening in promoting return to work.

 

3.7 Conclusion

Considering that CLBP is the leading cause of disability worldwide and those with yellow flags are known to suffer the worst and contribute most to societal cost it is surprising how few studies met the selection criteria. This review has shown that whilst the term yellow flags are used in the assessment literature and guidelines, the term psychosocial and the factors that make it up are used in the treatment literature. The studies selected highlight that passive, active; more comprehensive and simple education interventions can all positively impact the pain experience of this patient group. While passive interventions can improve pain, more whole body active approaches such whole body weight training or walking may be necessary to positively impact the psychosocial aspects. Comprehensive CBT and functional restorations are effective but the inclusion of work hardening may significantly aid in return to work. Pain education approaches involving pain neurophysiology education and pain acceptance were both effective compared with more traditional back school and pain avoidance approaches respectively. A combination of these may be useful clinically. The CFT approach was the most effective in terms of disability and self reported pain. Thus despite the lack of investigation in to several of the most prominent approaches this review shows the breadth of approaches available to clinicians.

 

C-Reactive Protein, Chronic Low Back Pain and, Diet and Lifestyle

Written by Kieran Macphail on . Posted in Back Pain and Diet, For Diet and Lifestyle Professionals, For Health Professionals, For Movement Therapists, Nutritional therapy

Abstract

C-Reactive Protein (CRP) is best known as an acute phase protein and is typically assessed in most general blood work. High sensitivity CRP (hsCRP) may be a useful clinical marker of chronic inflammatory states in musculoskeletal conditions. It appears that it is raised in inflammatory chronic low back pain (CLBP) and associated with reduced pain thresholds, weakness and reduced function. It is also possible CRP could contribute towards the development and maintenance of CLBP by activating the complement system which increases peripheral nociception. Diet and lifestyle factors can promote raised CRP. A hsCRP level of < 1mg/l appears ideal and the higher the level the more emphasis should be placed on chronic inflammation as a contributor to symptoms. Diet and lifestyle can significantly reduce CRP levels and may be a useful adjunct in treating CLBP patients with elevated CRP. This might make CRP a useful clinical marker of inflammation in CLBP and a therapeutic target for diet and lifestyle interventions.


Introduction

C-Reactive Protein (CRP) is best known as an acute phase protein and is typically assessed in most general blood work. More recently high sensitivity C-reactive protein (hsCRP) has been used in cardiovascular research as a marker of chronic inflammation. As chronic low back pain (CLBP) can have an inflammatory component it would be useful to have a clinical marker to assess in practice. Furthermore it may help us understand a component of how diet and lifestyle can influence CLBP.

C-Reactive Protein and Chronic Low Back Pain

In the 1940s CRP was considered as a possible marker of chronic low level inflammation but the standard assay lacks the sensitivity to determine normal ranges. Since the advent of the hsCRP test large-scale epidemiological studies have identified that CRP is a strong independent risk factor of future myocardial infarction, stroke, peripheral arterial disease, and vascular death among individuals without known cardiovascular disease [1]. In cardiovascular disease hsCRP is a sensitive and specific measure across many populations.  As these conditions are associated with inflammatory processes it is possible hsCRP may be a useful marker of chronic inflammation in musculoskeletal conditions such as chronic low back pain.

More recently CRP has received attention as a marker of chronic inflammation in musculoskeletal conditions. Chronic inflammation has been associated with arthritis [2], and chronic musculoskeletal injuries  [3-5]. Repetitive tissue injury has been theorised to contribute to lower level rises in chronic inflammation [3]. Inflammation and pain are intimately interrelated and pain perception may be higher in those with raised CRP. In a study of 99 pairs of twins, higher levels of CRP were associated with lower pain thresholds and increased pain sensation [6]. Similarly, in cancer patients CRP is significantly correlated with perceived pain [7]. Thus a hsCRP test could provide insight in to the inflammatory contribution chronic pain states.

CRP is also associated with poorer function in symptomatic individuals. Carp et al [4] found asymptomatic subjects averaged 0.8 mg/l, whereas those scoring 50-74 on the upper body musculoskeletal analysis (UMBA) averaged 1.8 mg/l, and those scoring over 75 on the UMBA averaged 5.4 mg/l. Interestingly, CRP was more strongly correlated with symptom levels than IL-1β, TNF-α and IL-6. Suggesting CRP may be the more clinically useful marker. These results are similar to that of Ravaglia et al [8] who found CRP levels were related to functional impairment. Cesari at al [9] found older adults with a CRP >6 mg/l had significant weakness and poorer physical function compared with those with a CRP <6 mg/l, conditions that may lead to chronic pain states. Carp et al explain their results by suggesting that worse disability is caused by worse injury and thus a greater acute phase response. However, injury and disability are not necessarily strongly associated. For example data from the LAIDBACK study has shown that at 3 years there is not a strong correlation between lumbar spine magnetic resonance imaging findings and symptoms [10]. It may be that in some patients it is the systemic inflammatory level that may be influencing the disability.

The association between raised CRP and CLBP is controversial. Studies looking at inflammatory pathologies such as herniated discs [11,12], nerve root inflammation [11], sciatica [13], and Modic changes [14] have shown positive correlations. Whereas those with smaller sample sizes and inclusion of acute and chronic patients in one heterogenous group have failed to show associations [15,16]. Briggs et al [17] conducted a population based study using 15 322 participants examining CRP levels, obesity and low back pain (LBP). They found that those with CRP levels of >30.0 mg/l had nearly twice the odds of reporting LBP. It should be noted they used standard CRP assessment and thus the figures are higher than for the hsCRP. Additionally, those with a body mass index >30 and elevated levels of CRP were 2 to 3 times as likely to report LBP. They found a significant association between LBP and elevated CRP, suggesting CRP could be a valuable marker of chronic inflammation in CLBP patients.

CRP is more than a useful marker and can contribute towards the development of chronic pain. Animal studies have suggested raised CRP plays a role in the chronic inflammation that leads to reduced tissue tolerance, and paves the way for chronic pain states [19]. Further, CRP may contribute to the initiation and continuation of joint pain [20]. In cancer patients elevated CRP can modulate pain [21] and contribute to the amplification and persistence of pain [22]. CRP can be viewed as both a marker for the underlying processes involved in increased pain sensation and a direct contributor to increased pain sensation. CRP activates the compliment system, which in turn sensitises peripheral nociceptors [23]. Effectors of the compliment cascade impact peripheral nociceptive sensitisation through the release of soluble factors and interacting directly with nociceptors. For example C5a and C3a injection can cause behavioural hyperalgesia in rats. In addition effectors of the complement cascade activate mast cells, which can sensitise nociceptors in multiple ways [23]. Thus CRP could feasibly contribute to the progression towards and maintenance of CLBP.

Diet and Lifestyle May Increase C-Reactive Protein Levels

As CRP may contribute to the underlying pathogenesis of CLBP it is prudent to consider some of the contributing factors in this process. Diet and lifestyle are powerful modulators of CRP levels and thus may contribute to the pathogenesis of CLBP through this mechanism. Smoking has been found to be associated with raised CRP [24]. Sleep disorders and poor sleep quality are associated with elevated CRP [25,26]. Psychological stress has been linked with raised CRP when perceived stress is increased [27], and during depression and loneliness [28]. Increased dietary saturated fat increases CRP whereas an equal increase in unsaturated fatty acids did not [29]. Higher carbohydrate intake was associated raised CRP levels in overweight and obese individuals [30]. Of the minerals magnesium has perhaps been most closely associated with CRP. Current recommendations for magnesium intake range from 310-420mg per day. King et al [31] found those who consumed less than the RDI of magnesium were greater than 1.45 times more likely to have a CRP level over 3.0 mg/l. 68% of US adults consumed less than the recommended daily intake (RDI), with 19% consuming less half the RDI. Of the vitamins deficiencies in vitamins B6 and D have received some interest. B6 appears to be utilised as part of the inflammatory process and thus those with elevated CRP level have significantly lower levels [32]. The interest in vitamin D and CRP has come from cardiovascular research. Low plasma vitamin D status is inversely associated with CRP levels [33]. Exercise can have both a positive and negative effect on CRP levels. However, overtraining such as that caused by playing professional soccer has been found to cause elevation in CRP during the season [34]. These results fit with the theme that deviations from a “healthy” lifestyle are associated with elevations in CRP levels.

Clinical Use

Given that there is an association between CLBP and CRP levels it is suggested a hsCRP test may be a useful clinical marker for managing these patients. This needs to be considered within a broader framework of the multitude of bio-psycho-social factors that influence CLBP. The question of what level is significant is unclear. In the literature there is no consensus for its use in musculoskeletal conditions. Levels as low as >1 mg/l have used, whilst the highest used is >6.0 mg/l. Thus in practice the measure can be used non-diagnostically with an appreciation of the cardiovascular research. It needs to be remembered that levels may be spiked during acute infection, trauma and post intense exercise. A level >1 mg/l is likely indicative of increased systemic inflammation, the higher this figure is the more significant a contributor it should be considered.

Pharmacological approaches have been considered for modifying CRP levels, with statins being potentially the most promising but diet and lifestyle changes can significantly improve CRP levels. An 8-week mindfulness programme reduced CRP levels from 2.98 to 2.09 [35]. Similarly, an 8-week programme of exercise decreased CRP levels by 38% and improved function in automotive workers with low back pain [36]. As visceral adipocytes produce CRP reducing body fat levels is another potential therapeutic target, and a carbohydrate restricted has been shown to reduce CRP levels [37]. More broadly going from 2 to 5 or 8 portions of fruit and vegetables per day significantly reduced CRP levels [38]. Furthermore, in a study of 1200 Puerto Rican adults aged 45-75 the variety of fruit and vegetable intake but not the quantity was inversely related with CRP levels [39]. Specifically, vitamin C intake from fruit and plasma vitamin C levels was inversely related to CRP levels in a cross-sectional study of 3258 British men aged 60-79 [40]. Other substances high in antioxidants have been found to favourably alter CRP levels including coffee [41], fruit juice [42,43] and dark chocolate [44]. Thus, diet and lifestyle modification of CRP levels may prove an effective component of CLBP treatment and may help reduce symptoms through other mechanisms as well.

Conclusion

CRP may be a useful clinical marker of chronic inflammation in chronic low back pain. It appears that it is elevated in inflammatory CLBP and associated with reduced tissue tolerance, reduced pain thresholds, weakness and reduced function. It may also contribute to peripheral sensitisation as part of the progression towards and maintenance of chronic pain. Diet and lifestyle factors can promote raised CRP. A hsCRP level of < 1mg/l appears ideal and the higher the level the more emphasis should be placed on chronic inflammation as a contributor to symptoms. Diet and lifestyle can significantly reduce CRP levels and may be a useful adjunct in treating CLBP patients with elevated CRP.

 

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