Non-drug management of chronic low back pain
Estimates suggest that, at any one time, 12–33% of the population have back pain.1 About 5% of a GP's workload involves consultations for the condition,2,3 and around 32% of patients who first present with back pain consult again within 3 months.3 Also, most will still have some pain or disability 1 year after consultation.3 Indeed, patients who have been off work with chronic back pain for 1–2 years are unlikely to return to any form of work in the foreseeable future, whatever treatment they receive.4 Here we discuss the place of non-drug management for patients with the condition.
About chronic low back pain
Non-specific low back pain is defined as pain, muscle tension or stiffness affecting the area generally described as “below the costal margin and above the inferior gluteal folds”, for which the pathological or anatomical cause is not clear, and the pain is uncomplicated by nerve root involvement or serious spinal pathology.1 Typically, chronic or persistent pain is defined as lasting beyond the normal healing time, usually 3 months.5 Chronic low back pain involves physiological, psychological and sociological factors; three-quarters of patients with chronic pain (such as low back pain) have it in multiple areas.6
Which non-drug treatments?
Various non-drug treatments are used for chronic low back pain. These include advice and education; joint manipulation, mobilisation and massage; exercise (including the Alexander technique, Pilates and yoga); acupuncture; behavioural therapy; lumbar supports; self-management programmes; multidisciplinary approaches; and mechanical and electrical interventions, such as therapeutic ultrasound, transcutaneous electrical nerve stimulation (TENS), interferential therapy (i.e. low frequency electrical stimulation of nerves), laser therapy, diathermy and traction. For some patients with persistent pain, a surgical option is sought even when no pathology is evident. Surgery will not be covered further here.
Potential difficulties in assessing the efficacy of non-drug interventions for chronic low back pain include the following: treatments can involve practitioners from different professional backgrounds using different clinical perspectives; adequate placebos and sham therapies can be difficult to devise; and blinding is often not possible. Here we review specific interventions regardless of the type of practitioner administering them.
Chiropractors, osteopaths, physiotherapists and some specifically trained doctors use manual therapy for chronic low back pain. This approach can include spinal manipulation, which involves high-velocity thrusts to a joint beyond its restricted range of movement;7 spinal mobilisation, which involves low-velocity passive movements within or at the limit of joint range;7 and massage therapy, which involves manipulation of muscles and connective tissue aimed at enhancing function and promoting relaxation and well-being. Within these broad classifications, different techniques and approaches are used.
Spinal manipulation and mobilisation
A systematic review pooled data from 39 randomised controlled trials involving a total of 5,486 patients that evaluated spinal manipulative therapy (manipulation and mobilisation) for patients with acute, subacute or chronic low back pain compared to various interventions.8 For chronic low back pain, spinal manipulative therapy was more effective than sham therapy in reducing both short-term pain (10mm difference on a 100mm visual analogue scale, 95% CI 3mm to 17mm) and long-term pain (19mm difference, 95% CI 3mm to 35mm), and in improving short-term function (3.3 points difference on the Roland-Morris Disability Questionnaire [RMDQ, see Box 1], 95% CI 0.6 to 6.0). It was also said to be more effective than therapies widely considered to be ineffective or perhaps harmful (i.e. traction, corset, bed rest, home care, topical gel, no treatment, diathermy and minimal massage), again, in terms of short-term pain (4mm, 95% CI 0mm to 8mm) and short-term function (2.6 points, 95% CI 0.5 to 4.8). However, the reviewers concluded that spinal manipulative therapy was neither superior nor inferior to other advocated therapies, including analgesics, exercises, physical therapy, and back schools. They therefore concluded that spinal manipulative therapy was one of several options of “modest effectiveness” for low back pain.
Roland-Morris Disability Questionnaire
The RMDQ comprises a list of 24 sentences that a group of people with back pain used to describe themselves when they had the pain.9 People completing the questionnaire are asked to tick all the sentences that describe how they are feeling that day, and their RMDQ score is the total number of sentences ticked (i.e. it can range from 0 to 24).
Another systematic review, involving 31 randomised controlled trials and a total of 5,202 patients, assessed spinal manipulation and mobilisation for acute or chronic low back or neck pain.10 The reviewers concluded that there was moderate evidence that spinal manipulation plus strengthening exercises had an effect similar to NSAIDs in terms of pain relief in both the short and long term. They also concluded that there was moderate evidence that manipulation plus mobilisation was superior to physical therapy or home exercise for reducing disability in the long term, and more effective in terms of “patient improvement” in the short term than placebo treatment or GP care, and in the long term compared to physical therapy.
A third systematic review including data from eight randomised controlled trials involving patients with chronic low back pain found no evidence that spinal manipulative therapy produced a clinically significant reduction in pain when compared with sham treatment, nor that it improved disability compared with NSAIDs.11 The reviewers also concluded that it was not clear whether spinal manipulative therapy was more effective than NSAIDs in reducing pain.
Later clinical trials
Since these systematic reviews, a randomised controlled trial involving 1,334 patients (aged 18–65 years) with simple low back pain (i.e. pain of musculoskeletal origin) for at least 28 days compared a spinal manipulation package, an exercise programme, or a combination of both, with “best care” in general practice12 (discussed again below*). Patients had to agree to avoid physical treatment other than trial treatments for 3 months. All patients received advice to continue normal activities and avoid rest, and had access to The back book (see Box 2).13 The practitioners carrying out manipulation agreed to perform high-velocity thrusts on most patients at least once, although the manipulation package was broad.14 Patients in the exercise programme could attend up to eight 60-minute sessions over 4–8 weeks, plus a class after 12 weeks. Those in the manipulation group could have up to eight 20-minute sessions, if necessary, over 12 weeks. Relative to best care, spinal manipulation improved back function as measured by the RMDQ (the primary outcome measure) by a small to moderate margin at 3 months (1.6 points difference, 95% CI 0.8 to 2.3), and by a smaller margin at 1 year (1.0 points difference, 95% CI 0.2 to 1.8).
About The back book
The back book offers advice on coping with back pain and leading a normal life. Key features include back facts, the causes of back pain and exercises to relieve back pain. It can be ordered online at www.tso.co.uk/bookshop, or via the telephone on 0870 600 5522.
Another randomised controlled trial (discussed again below**), involving 240 patients (aged 18–80 years) with non-specific low back pain for at least 3 months, compared spinal manipulative therapy (up to 12 sessions), general exercise (including strengthening, stretching and aerobic exercises) and motor control exercise (retraining of specific trunk muscles using ultrasound feedback).15 Patients were encouraged to exercise daily and attend 12 training sessions. The primary outcome measures were patient-specific function (PSF; total score range 3–30) and global perceived effect (GPE; measured on an 11-point scale) at 8 weeks. Those receiving manipulative therapy improved more than those in the general exercise group (between group differences: PSF 2.3, 95% CI 0.4 to 4.2; p=0.016 and GPE 1.2, 95% CI 0.4 to 2.0; p=0.004). There was little difference between the manipulative therapy and motor control exercise groups.
A systematic review pooled data from 13 randomised controlled trials involving a total of 1,596 patients to assess massage therapy for non-specific low back pain (acute, subacute or chronic).16 The types, duration and frequency of massage varied among the studies. In two studies, massage was applied with a mechanical device, while in the rest, it was applied directly by hand and, in two studies, a specific oil was used. The reviewers found that massage was more effective than sham treatment (two studies) in terms of pain relief in the short term (standardised mean difference [SMD] −0.92, 95% CI −1.35 to −0.48), and improvement in disability in the short term (SMD −1.76, 95% CI −3.19 to −0.32) and long term (SMD −0.96, 95% CI −1.58 to −0.35). The studies reviewed suggested that massage has long-lasting effects (i.e. at least 1 year after the end of treatment). The reviewers concluded that massage might be beneficial for patients with chronic non-specific low back pain, especially if it is combined with exercise and education.
Later clinical trial
Since the systematic review, a randomised controlled trial, involving 579 patients (aged 18–65 years) with chronic or recurrent low back pain, has compared massage (six sessions) or a course of Alexander technique lessons (6 or 24 lessons) with GP “normal care”, all administered alone or in combination with an exercise prescription plus behavioural counselling17 (discussed again below***). Compared to normal care, at 3 months, there was an improvement with massage in RMDQ score (–1.96, 95% CI −3.18 to −0.74; p=0.002) and a fall in number of days spent in pain during the past 4 weeks (–13, 95% CI −18 to −8; p<0.001), the primary outcome measures; the fall in days in pain was still evident at 1 year (–7, 95% CI −12 to −2; p=0.004), unlike the improvement in function.
Transient unwanted effects, such as headache, extra pain and stiffness, appear to be frequent after spinal manipulation (i.e. following at least 50% of treatments).18,19 However, prospective cohort studies have found no serious adverse events following spinal manipulation (at all levels of the spine).19,–,22 The incidence of serious adverse events (e.g. cerebrovascular accidents, disc herniation, cauda equina syndrome) is estimated to be about 1 event per 1–2 million treatments, although there are questions about the accuracy of these data, mainly due to methodological difficulties in collecting them.23 Serious adverse events due to massage are extremely rare.16,24
Staying active rather than resting is now the recommended course of action for people with non-specific low back pain.13 We know of no published randomised controlled trials comparing advice to maintain or increase self-directed physical activity with no advice or advice to rest. However, several published randomised controlled trials have assessed exercise therapy or exercise programmes for low back pain.
A systematic review pooled data from 61 randomised controlled trials involving a total of 6,390 patients to assess exercise therapy for adults with non-specific low back pain (43 trials for chronic pain; a total of 3,907 patients).25 Such therapy was found to be “slightly effective” for chronic low back pain compared to either no treatment or placebo, or to conservative treatments, at all follow-up periods. Pooled weighted mean improvement compared to all other interventions was 7.29 points (95% CI 3.7 to 10.9) out of 100 for pain and 2.5 points (95% CI 1.0 to 3.9) out of 100 for function at earliest follow-up, both for recruits from the general population and patients consulting a healthcare provider. When data from patients only were pooled, mean improvement was greater: 13.3 points (95% CI 5.5 to 21.1) for pain and 6.9 (2.2 to 11.7) for function.
Later clinical trials
In one randomised controlled trial (described above*), which compared the effectiveness of an exercise programme, spinal manipulation package, or a combination of both, with “best care” in general practice in patients with simple low back pain for at least 28 days, the exercise programme produced improvement in mean RMDQ at 3 months (by 1.4, 95% CI 0.6 to 2.1), but not 12 months.12 Manipulation followed by exercise produced improvement at 3 months in RMDQ scores (1.9, 95% CI 1.2 to 2.6) and 1 year (1.3, 95% CI 0.5 to 2.1).
In a second trial (described above**), which compared general exercise, motor control exercise and spinal manipulative therapy in patients with chronic non-specific low back pain, those in the motor control exercise group improved more than those in the general exercise group (between group differences: PSF 2.9, 95% CI 0.9 to 4.8 and GPE 1.7, 95% CI 0.9 to 2.4).15
In a third trial (described above***), which compared the Alexander technique or massage with “normal care”, there was improvement in the RMDQ scores at 3 months with Alexander technique lessons compared to “normal care” (six lessons: −1.71, 95% CI −2.95 to −0.47; p=0.007 and 24 lessons: −2.91, 95% CI −4.16 to −1.66; p=0.001) and a reduction in days in pain (–11, 95% CI −16 to −6; p<0.001 and −16, 95% CI −21 to −11; p<0.001, respectively), and the effects were still apparent at 1 year.17
Acupuncture involves the insertion of fine needles into the body at specific sites (acupuncture points), most commonly in the UK according to the Traditional Chinese Medicine (TCM) approach or the medical acupuncture approach.26 For a painful condition such as low back pain, needles are typically placed near the painful area, and possibly elsewhere, and may be manipulated manually to produce a ‘needle sensation’, warmed, or stimulated electrically (electroacupuncture).
One systematic review including 23 randomised controlled trials and a total of 6,359 patients with non-specific subacute or chronic low back pain compared acupuncture with sham acupuncture, conventional therapy (i.e. any other therapy except acupuncture) or no therapy.27 The reviewers found moderate evidence that acupuncture was more effective than no treatment for pain relief and functional improvement in the short term, and conflicting evidence for intermediate-term pain relief. They found strong evidence for no difference between acupuncture and sham acupuncture for short-term and intermediate-term pain relief and for functional improvement. The evidence for acupuncture versus conventional therapy was conflicting. However, the reviewers found strong evidence that acupuncture combined with conventional therapy was more effective than conventional therapy alone for pain relief, and moderate evidence that it improved function more.
Another systematic review pooled data from 35 randomised controlled trials including a total of 2,861 patients and comparing acupuncture with other interventions for nonspecific subacute or chronic low back pain, and dry-needling (i.e. inserting an acupuncture needle through the skin at a site of pain not necessarily recognised as an acupuncture point) for myofascial pain syndrome in the low-back region.28 The reviewers found that, compared to no treatment, there was evidence of pain relief (SMD −0.73, 95% CI −1.19 to −0.28) and functional improvement (effect size 0.63, 95% CI 0.19 to 1.08) with acupuncture for chronic low back pain. They also found that, compared with sham therapy, there was evidence of pain relief (weighted mean difference [WMD] −17.79, 95% CI −25.50 to −10.07), effects observed only in the short term (less than 3 months). The reviewers concluded that, “compared to other conventional or ‘alternative’ treatments, acupuncture is no better for measures of pain and function”, but that there was evidence that acupuncture plus conventional therapies “relieves pain and improves function better than conventional therapies alone”.
A third systematic review, including 33 randomised controlled trials comparing acupuncture with other sham, other active or no additional treatment, pooled data from 22 trials of acupuncture for chronic low back pain.29 With respect to short-term pain, acupuncture was found to be more effective than sham acupuncture (effect size 0.58, 95% CI 0.36 to 0.80), sham TENS (0.42, 95% CI 0.05 to 0.79) or no additional treatment (0.69, 95% CI 0.40 to 0.98), but no more effective than massage, medication or TENS, and less effective than spinal manipulation (–1.32, 95% CI −1.87 to −0.77). With respect to long-term pain, acupuncture was found to be more effective than sham TENS (effect size 0.62, 95% CI 0.03 to 1.22) and no additional treatment (0.74, 95% CI 0.02 to 1.47), but no more effective than sham acupuncture or TENS, and less effective than massage (–0.40, 95% CI −0.71 to −0.09). With respect to function status, acupuncture was superior only to no additional treatment and then only in the short term.
Later clinical trial
Since the systematic reviews, one randomised controlled trial including 638 adults with uncomplicated chronic low back pain has compared individualised acupuncture, standardised acupuncture (eight points commonly used for chronic low back pain), simulated acupuncture (a toothpick in a needle guide tube with point stimulation) and “usual care”.30 Acupuncture was given twice weekly for 3 weeks and then weekly for 4 weeks. At 8, 26 and 52 weeks, all the acupuncture groups had improved significantly more than the usual care group in terms of the primary outcome measures (function measured using the RMDQ, and symptom “bothersomeness” score on a scale of 0 to 10), but there was no significant difference between acupuncture groups.
When acupuncture is given by a trained practitioner, the risk of serious injury (e.g. a punctured lung) or infection is very low (estimated risk 0.05 serious adverse events per 10,000 treatments and 0.55 per 10,000 individual patients).26 Potential mild transient reactions at the site of needling include bleeding (occurring at 0.4% of needling sites), superficial bruising (1.7%) or pain (1.2%).26
Behavioural therapy comprises a psychological approach to help patients change negative beliefs and behaviours.
A systematic review including 21 randomised controlled trials assessing behavioural treatment for non-specific chronic low back pain found that “combined cognitive-respondent therapy and progressive relaxation therapy alone are effective treatment modalities for short-term pain reduction”.31 However, whether these results would last in the long term was unclear, and the reviewers could find no significant differences among the various types of behavioural treatment, nor evidence to suggest which patients would benefit most from such treatment.
Multidisciplinary treatment usually consists of intensive bio-psychosocial training by a team of healthcare practitioners. However, multidisciplinary clinics (including back schools) vary in structure and content, and reviewing data from such heterogeneous approaches is difficult.
A systematic review of 10 trials involving a total of 1,964 patients assessed multidisciplinary bio-psychosocial rehabilitation for chronic low back pain.32 Data were not pooled because of heterogeneity. The reviewers found that, compared with inpatient or outpatient non-multidisciplinary treatments, there was strong evidence that intensive rehabilitation (more than 100 hours) with functional restoration improved function and moderate evidence that it reduced pain. A review of systematic reviews concluded that there is evidence for “the effectiveness of intensive multidisciplinary pain programmes for chronic low back pain patients in terms of their effect on functional improvement and pain reduction”.33
A systematic review of 19 randomised controlled trials involving a total of 3,584 patients found moderate evidence that, for patients with chronic low back pain, back schools in an occupational setting are more effective for reducing pain, improving function and returning to work, in both the short and intermediate term, compared to exercise, manipulation, myofascial therapy, advice, placebo or waiting-list controls.34
Later clinical trials
Several randomised controlled trials published since the reviews provide conflicting evidence on whether intensive bio-psychosocial programmes are any more effective than individual approaches for reducing pain and improving function in patients with non-specific chronic low back pain.35,–,39
Self-management, or expert-patient, programmes aim to enable patients with chronic pain conditions to learn new skills to manage their condition.40,41 These are free 6-week courses40 originally developed in Stanford, USA for patients with arthritis.41,42 Randomised controlled trials indicate that such education programmes for chronic conditions (not necessarily chronic low back pain) may improve cognitive symptom management and frequency of aerobic exercise, increase self-efficacy to manage symptoms and have a small, short-term, clinically unimportant impact on health status.43
Lumbar supports are used with the aim of treating low back pain, or preventing its onset or recurrence.
One systematic review evaluated seven preventive studies (involving a total of 14,437 participants) and eight treatment studies (a total of 1,361 patients) that had reported on any type of lumbar support.44 The reviewers concluded that there was moderate evidence that lumbar supports were no more effective than no intervention or training in preventing low back pain, and conflicting evidence on whether they provide added benefit to other preventive interventions. They also concluded that the effectiveness of lumbar supports as treatment for low back pain in relation to no treatment or other interventions was unclear.
Other non-drug treatments
Other non-drug treatments for chronic low back pain include mechanical and electrical interventions such as therapeutic ultrasound, TENS, interferential therapy, laser therapy, diathermy and traction.
A systematic review pooled data from four randomised controlled trials comparing TENS and placebo for chronic low back pain and involving a total of 585 patients.45 The reviewers found conflicting evidence on whether TENS was beneficial in reducing back pain intensity and consistent evidence that it did not improve back-specific functional status.
A systematic review of low-level laser therapy for non-specific low back pain (including seven randomised controlled trials involving a total of 554 patients) found insufficient data to draw firm conclusions on the clinical effect of this approach.46
A systematic review of traction for low back pain (pooling data from 25 randomised controlled trials including a total of 2,206 patients) concluded that traction (either continuous or intermittent) was unlikely to be effective as a single treatment for chronic low back pain with or without sciatica.47
We know of no published randomised controlled trials comparing therapeutic ultrasound, interferential therapy or diathermy with control treatment for patients with non-specific low back pain.
Advice from guidelines
National Institute for Health and Clinical Excellence
A National Institute for Health and Clinical Excellence (NICE) guideline recommends that people with non-specific persistent or recurrent low back pain (i.e. for more than 6 weeks but less than 1 year) should be provided with advice and information to promote self-management, and offered one of the following, taking into account their preference: an exercise programme, a course of manual therapy, or a course of acupuncture (see Box 3).48 The guideline also states that patients should be offered another of these options, if the chosen treatment does not result in satisfactory improvement, and referred for a combined physical and psychological treatment programme, if they have received at least one of these options and have high disability and/or significant psychological distress.
Summary of NICE recommendations for persistent non-specific low back pain48
Physical activity and exercise
■ Consider offering a structured exercise programme (e.g. aerobic activity, movement instruction, muscle strengthening, postural control, stretching) tailored to the person (up to eight sessions over 12 weeks).
■ Offer a group supervised exercise programme, in a group of up to 10 people.
■ A one-to-one supervised exercise programme may be offered, if a group programme is considered unsuitable.
Manual therapy (i.e. spinal manipulation, spinal mobilisation and massage)
■ Consider offering a course of manual therapy, including spinal manipulation (up to nine sessions over 12 weeks).
■ Consider offering a course of acupuncture needling (up to 10 sessions over 12 weeks).
Combined physical and psychological treatment programme
■ Consider referral for a combined physical and psychological treatment programme (around 100 hours over up to 8 weeks).
The NICE guideline advises against laser therapy; interferential therapy; therapeutic ultrasound; TENS; lumbar supports; or traction.
Guidelines from the European Commission on the management of chronic non-specific low back pain recommend exercise therapy, cognitive behavioural therapy (CBT), brief educational interventions and multidisciplinary (bio-psychosocial) treatments, and advise considering short courses of manipulation.1 They advise against massage; acupuncture; ultrasound therapy; laser therapy; TENS; interferential therapy; lumbar supports; and traction.
The American Pain Society/American College of Physicians clinical practice guideline concluded that therapies with “good” evidence of moderate efficacy for chronic low back pain are CBT, exercise, spinal manipulation and interdisciplinary rehabilitation, and those with “fair” evidence are acupuncture, massage and yoga.49
Cost and practical implications
NHS care for chronic low back pain typically involves eventual referral from a generalist to a specialist; few multidisciplinary chronic pain clinics exist, and patients with chronic pain are often referred from one specialist to another.50 However, direct access to physiotherapy for common musculoskeletal conditions such as low back pain is increasing.51 One estimate for the cost of care in the NHS ranges from £296 for a course of physiotherapy rising to £1,911 for a patient seen in physiotherapy, orthopaedic and pain clinics.50
In one cost-effectiveness analysis of a randomised controlled trial comparing Alexander technique, exercise and massage, reported costs ranged from £30 for prescription exercise to £596 for 24 lessons in the Alexander technique.52 A combination of six lessons in the Alexander technique followed by exercise was the most effective and cost-effective option (an additional £64 per point on the RMDQ score, £43 per additional pain-free day during the past 4 weeks, £5,322 per quality-adjusted life year [QALY] gained). Another randomised controlled trial, which compared the effectiveness of manipulation, an exercise programme and “best care” in general practice, reported mean additional treatment costs relative to best care of £195 for manipulation, £140 for exercise and £125 for combined manipulation and exercise interventions.53 For all three active treatments, compared with best care alone, there was an estimate of £3,800 per QALY gained. In a randomised controlled trial comparing acupuncture with “usual care”, the healthcare cost of acupuncture over a 2-year trial period was £460 compared to £345 for GP usual care.54,55 The mean incremental health gain from acupuncture at 24 months was 0.027 QALYs (95% CI −0.056 to +0.110), leading to a base case estimate of £4,241 per QALY gained. These cost/QALYs are well below the £30,000 used by NICE to define cost-effectiveness.
The services and staff needed to enable people with chronic low back pain to access the NICE-recommended treatment programmes are not currently widely available. Nor is it obvious where the funding for such treatment will come from, although the guideline suggests that it may come from the disinvestment in treatments now not recommended, such as spinal injections.48 For the programmes to become accessible to all those eligible, current services will need to be reorganised and the pool of appropriately qualified practitioners will need to be expanded, for example, by employing them within the NHS and training some existing NHS staff.
Estimates suggest that up to one-third of people have back pain at any one time. Of those who consult a GP with the condition, most will still have some pain or disability 1 year later.
There are many non-drug treatments for chronic non-specific low back pain, but the published evidence for these is variable. Acupuncture, manual therapy (i.e. spinal manipulation and mobilisation, massage) and exercise therapy all seem to reduce pain and improve function. Also, serious complications from such interventions seem to be rare. Intensive bio-psychosocial programmes have also been shown to help, but whether behavioural approaches alone are beneficial is unclear. There is insufficient evidence to support the use of transcutaneous electrical nerve stimulation, laser therapy, interferential therapy, therapeutic ultrasound, lumbar supports or traction for chronic low back pain.
In the first instance, patients should be given reassurance and advice, and information about how to self-manage their condition and staying active. Also, a course of acupuncture or manual therapy, or an exercise programme, is probably worth trying. Giving patients choice as to which of these interventions they try, as suggested in the recent National Institute for Health and Clinical Excellence (NICE) guideline on early management of persistent non-specific low back pain, seems sensible. However, access to these modalities is currently limited within the NHS, so services will need to be reorganised and the pool of appropriately qualified practitioners will need to be expanded before the NICE recommendations can be widely implemented.
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[R=randomised controlled trial; M=meta-analysis]
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