Roger Chou, MD, and Laurie Hoyt Huffman, MS
Clinical Efficacy Assessment Subcommittee
of the American College of Physicians
and the American College of Physicians/
American Pain Society Low Back Pain Guidelines Panel
The Abstract:
Background: Many nonpharmacologic therapies are available for treatment of low back pain.
Purpose: To assess benefits and harms of acupuncture, back schools, psychological therapies, exercise therapy, functional restoration, interdisciplinary therapy, massage, physical therapies (interferential therapy, low-level laser therapy, lumbar supports, shortwave diathermy, superficial heat, traction, transcutaneous electrical nerve stimulation, and ultrasonography), spinal manipulation, and yoga for acute or chronic low back pain (with or without leg pain).
Data Sources: English-language studies were identified through searches of MEDLINE (through November 2006) and the Cochrane Database of Systematic Reviews (2006, Issue 4). These electronic searches were supplemented by hand searching of reference lists and additional citations suggested by experts.
Study Selection: Systematic reviews and randomized trials of 1 or more of the preceding therapies for acute or chronic low back pain (with or without leg pain) that reported pain outcomes, back-specific function, general health status, work disability, or patient satisfaction.
Data Extraction: We abstracted information about study design, population characteristics, interventions, outcomes, and adverse events. To grade methodological quality, we used the Oxman criteria for systematic reviews and the Cochrane Back Review Group criteria for individual trials.
Data Synthesis: We found good evidence that cognitive-behavioral therapy, exercise, spinal manipulation, and interdisciplinary rehabilitation are all moderately effective for chronic or subacute (>4 weeks’ duration) low back pain. Benefits over placebo, sham therapy, or no treatment averaged 10 to 20 points on a 100-point visual analogue pain scale, 2 to 4 points on the Roland–Morris Disability Questionnaire, or a standardized mean difference of 0.5 to 0.8. We found fair evidence that acupuncture, massage, yoga (Viniyoga), and functional restoration are also effective for chronic low back pain. For acute low back pain (<4 weeks’ duration), the only nonpharmacologic therapies with evidence of efficacy are superficial heat (good evidence for moderate benefits) and spinal manipulation (fair evidence for small to moderate benefits). Although serious harms seemed to be rare, data on harms were poorly reported. No trials addressed optimal sequencing of therapies, and methods for tailoring therapy to individual patients are still in early stages of development. Evidence is insufficient to evaluate the efficacy of therapies for sciatica.
Limitations: Our primary source of data was systematic reviews. We included non–English-language trials only if they were included in English-language systematic reviews.
Conclusions: Therapies with good evidence of moderate efficacy for chronic or subacute low back pain are cognitive-behavioral therapy, exercise, spinal manipulation, and interdisciplinary rehabilitation. For acute low back pain, the only therapy with good evidence of efficacy is superficial heat.
From the Full-Text Article:
Spinal Manipulation, Massage, and Acupuncture
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Spinal Manipulation
Sixty-nine unique trials on efficacy of spinal manipulation were included in 12 systematic reviews [15, 55–63, 68–71]. Four other systematic reviews focused on harms associated with spinal manipulation [21, 64–67].
For acute low back pain, a higher-quality Cochrane review found spinal manipulation to be slightly to moderately superior to sham manipulation for short-term pain relief in a meta-regression analysis (weighted mean difference, -10 points on a 100-point visual analogue scale [95% CI, -17 to -2 points]) [15, 55]. However, this estimate is mainly based on a lower-quality trial of patients with acute or subacute sacroiliac pain [154]. Short-term effects on the RDQ (2 trials, 1 higher-quality) were moderate but did not reach statistical significance (weighted mean difference, -2.8 points [CI, -5.6 to 0.1 points]). Differences between spinal manipulation and therapies judged ineffective or harmful (traction, bed rest, home care, topical gel, no treatment, diathermy, and minimal massage) did not reach clinical significance for pain (weighted mean difference, -4 points [CI, -8 to -1 points]) and reached clinical but not statistical significance on the RDQ (weighted mean difference, -2.1 points [CI, -4.4 to 0.2 points]). There were no clear differences between spinal manipulation and usual care or analgesics (3 trials), physical therapy or exercises (5 trials), and back schools (2 trials).
For chronic low back pain, the Cochrane review found spinal manipulation moderately superior to sham manipulation (3 trials) and therapies thought to be ineffective or harmful (5 trials). Against sham manipulation, differences in short- and long-term pain averaged 10 and 19 points on a 100-point visual analogue scale, and differences for short-term function averaged 3.3 points on the RDQ. There were no differences between manipulation and general practitioner care or analgesics (6 trials), physical therapy or exercises (4 trials), and back school (3 trials). Evidence was insufficient to conclude that effectiveness of spinal manipulation varies depending on the presence or absence of radiating pain or the profession or training of the manipulator.
Five higher-quality systematic reviews reached conclusions generally consistent with those of the Cochrane review [58, 60, 61, 69, 70]. Two recent, large trials [133, 134] not included in the systematic reviews also reported consistent results (Appendix Table 8 [130, 132–134, 155]). For low back pain of unspecified duration, 1 higher-quality trial (681 patients) found no differences in pain, functional status, or other outcomes between patients randomly assigned to chiropractic versus medical management [133]. The other trial (1334 patients) found spinal manipulation to be slightly superior to usual care for pain and disability (about 5 points on 100-point scales) after 3 months in patients with subacute or chronic low back pain, although effects were not as pronounced after 12 months, and differences on the RDQ did not reach clinical significance (about 1 point) [134]. Manipulation and exercise did not significantly differ, and the addition of manipulation to exercise therapy was no better than exercise alone.
Two lower-quality systematic reviews found spinal manipulation superior to some other effective interventions [57, 68]. However, these conclusions were based on sparse data (1 to 3 trials, often lower-quality and often with small sample sizes).
Five systematic reviews consistently found that serious adverse events after spinal manipulation (such as worsening lumbar disc herniation or the cauda equina syndrome) were very rare [64–67, 69]. One systematic review found no serious complications reported in more than 70 controlled clinical trials [65]. Including data from observational studies, the risk for a serious adverse event was estimated as less than 1 per 1 million patient visits [66, 67].
One higher-quality randomized trial evaluated a decision tool for identifying patients more likely to benefit from spinal manipulation [156]. It found that patients who met at least 4 of 5 predefined criteria had a higher likelihood of greater than 50% improvement in ODI scores when randomly assigned to spinal manipulation (odds ratio [OR], 60.8 [CI, 5.2 to 704.7]) compared with those who had negative findings according to the rule who were randomly assigned to manipulation (OR, 2.4 [CI, 0.83 to 6.9]) and those with positive findings according to the rule who were randomly assigned to exercise (OR, 1.0 [CI, 0.28 to 3.6]). However, no studies have examined how applying the decision tool versus not using the tool affects clinical outcomes, and the decision tool may not be practical for many primary care settings because it requires the clinician to perform and interpret potentially unfamiliar physical examination maneuvers and administer a specific questionnaire. A more pragmatic version of the decision tool has not been prospectively validated [157].
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Massage
Eight unique trials of massage were included in 2 systematic reviews [26, 27, 69]. For acute low back pain, evidence is insufficient to determine efficacy of massage (1 lower-quality trial evaluating a minimal massage intervention [158]). One higher-quality trial found combined treatment with massage, exercise, and education to be superior to exercise and education alone for subacute or chronic low back pain 1 month after treatment [159].
For chronic low back pain, a higher-quality Cochrane review found no clear differences between massage and manipulation at the end of a course of treatment (3 lower-quality trials) [26, 27]. Superficial massage was inferior to transcutaneous electrical nerve stimulation (TENS) for relieving pain in 1 higher-quality trial [160]. Single trials found massage similar in effectiveness to corsets and exercise and moderately superior to relaxation therapy, acupuncture, sham laser, and self-care education [26, 27]. Nearly all trials assessed outcomes only during or shortly after (within 1 month) a course of treatment. However, 1 higher-quality trial found that beneficial effects of massage compared with acupuncture and self-care education persisted for 1 year [161]. Results of a second systematic review are consistent with the Cochrane review [69].
Only 1 trial (rated higher-quality) directly compared different massage techniques. It found acupuncture massage superior to classical (Swedish) massage [162]. Massage seemed more effective in trials that used a trained massage therapist with many years of experience or a licensed massage therapist [26, 27]. Evidence was insufficient to determine effects of the number or duration of massage sessions on efficacy. Several trials with negative results evaluated superficial massage techniques, brief treatment sessions (10 to 15 minutes), or few sessions (<5).
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Acupuncture
Fifty-one unique trials on efficacy of acupuncture were included in 3 systematic reviews [16–18, 69]. All of the systematic reviews identified substantial methodological shortcomings in most trials. About one third of the trials were conducted in Asia. A fourth systematic review focused on adverse events associated with acupuncture and included observational studies [163].
For acute low back pain, 2 higher-quality systematic reviews found sparse, inconclusive evidence from 4 small trials on efficacy of acupuncture versus sham acupuncture or other interventions [16–18].
For chronic low back pain, both systematic reviews found acupuncture moderately more effective than no treatment or sham treatments for short-term (<6 weeks’ [16] or <3 months’ [17, 18] duration) pain relief. Acupuncture was also associated with moderate short-term improvements in functional status compared with no treatment (standardized mean differences, 0.62 [CI, 0.30 to 0.95] [16], and 0.63 [CI, 0.19 to 1.08] [17, 18]), but not compared with sham therapies. A recent, higher-quality trial not included in the systematic reviews found no differences between acupuncture and sham acupuncture for pain or function (Appendix Table 8) [130].
Evidence of longer-term benefits from acupuncture is mixed. Acupuncture was moderately superior for long-term (>6 weeks’ duration) pain relief compared with sham TENS in 2 trials and compared with no additional treatment in 5 trials, although there were no significant differences compared with sham acupuncture [16]. One higher-quality trial found no differences in pain 1 year after acupuncture therapy compared with provision of a self-care education book [161]. A higher-quality trial not included in the systematic reviews found clinically insignificant differences (<5 points on 100-point scales) between acupuncture and no acupuncture for pain and function after 6 months (Appendix Table 8) [132]. Another recent, higher-quality trial found acupuncture slightly superior to usual care on Short Form-36 pain scores after 24 months (weighted mean difference, 8 points [CI, 0.7 to 15.3 points]) and for recent use of medications for low back pain (60% vs. 41%), although ODI scores and other outcomes did not differ [131].
Efficacy does not clearly differ between acupuncture and massage, analgesic medication, or TENS (each evaluated in 1 to 4 trials) [16–18]. Although 2 trials found acupuncture inferior to spinal manipulation for short-term pain relief, both were rated lower-quality [16]. The addition of acupuncture to a variety of noninvasive interventions significantly improved pain and function through 3 to 12 months in 4 higher-quality trials [17, 18].
Few higher-quality trials directly compared different acupuncture techniques. One trial found deep-stimulation acupuncture to be superior to superficial stimulation for immediate outcomes [164]. Another found no difference between manual acupuncture and electroacupuncture [165].
Only 14 of 35 trials of acupuncture reported any complications or side effects [17, 18]. Minor complications occurred in 5% (13 of 245) of patients receiving acupuncture. A systematic review of acupuncture for various conditions (data from >250 000 treatments) found wide variation in rates of adverse events, ranging from 1% to 45% for needle pain and 0.03% to 38% for bleeding [163]. Feelings of faintness and syncope occurred after 0% to 0.3% of treatments. Serious adverse events were rare. Pneumothorax was reported in 2 patients, and there were no cases of infections.
Discussion
This review synthesizes evidence from systematic reviews and randomized, controlled trials of 17 nonpharmacologic therapies for low back pain. Nearly all therapies were evaluated in patients with nonspecific low back pain or in mixed populations of patients with and without sciatica. Main results are summarized in Appendix Tables 10 (acute low back pain), 11 (chronic or subacute low back pain), and 12 (back pain with sciatica).
We found good evidence that psychological interventions (cognitive-behavioral therapy and progressive relaxation), exercise, interdisciplinary rehabilitation, functional restoration, and spinal manipulation are effective for chronic or subacute (>4 weeks’ duration) low back pain. Compared with placebo or sham therapies, these interventions were associated with moderate effects, with differences for pain relief in the range of 10 to 20 points on a 100-point visual analogue pain scale, 2 to 4 points on the RDQ, or a standardized mean difference of 0.5 to 0.8. The exception was exercise therapy, which was associated with small to moderate (10 points on a 100-point visual analogue pain scale) effects on pain. We found fair evidence that acupuncture is more effective than sham acupuncture, and fair evidence that massage is similar in efficacy to other noninvasive interventions for chronic low back pain. We found little evidence of clinically meaningful, consistent differences between most interventions found effective. One exception was intensive interdisciplinary rehabilitation, which was moderately more effective than noninterdisciplinary rehabilitation for improving pain and function. We also found fair evidence that Viniyoga is slightly superior to traditional exercises for functional status and use of analgesic medications.
For acute low back pain (<4 weeks’ duration), the only nonpharmacologic therapies with evidence of efficacy are superficial heat (good evidence for moderate benefits) and spinal manipulation (fair evidence for small to moderate benefits). Other noninvasive therapies (back schools, interferential therapy, low-level laser therapy, lumbar supports, TENS, traction, and ultrasonography) have not been shown to be effective for either chronic or subacute or acute low back pain.
We found only rare reports of serious adverse events for all of the noninvasive therapies evaluated in this review. However, assessment and reporting of harms were generally suboptimal. For example, less than half of the trials of acupuncture reported adverse events [17]. Better reporting of harms is needed for more balanced assessments of interventions [182].
Our evidence synthesis has several potential limitations. First, because of the large number of published trials, our primary source of data was systematic reviews. The reliability of systematic reviews depends on how well they are conducted. We therefore focused on findings from higher-quality systematic reviews, which are less likely than lower-quality systematic reviews to report positive findings [20, 21]. In addition, when multiple recent systematic reviews were available for an intervention, we found overall conclusions to be generally consistent. Second, we only included randomized, controlled trials for assessments of efficacy. Although well-conducted randomized, controlled trials are less susceptible to bias than other study designs, nearly all trials were conducted in ideal settings and selected populations, usually with short-term follow-up. “Effectiveness” trials in less highly selected populations could provide additional information on benefits in real-world practice. Third, language bias could affect our results because we included non–English-language trials only if already included in English-language systematic reviews. However, systematic reviews of acupuncture included Asian-language trials [16, 17], and systematic reviews of other interventions with no language restrictions identified few non–English-language studies [55, 183]. Fourth, reliable assessments for potential publication bias were not possible for most of the interventions included in this review because of small numbers of trials [184]. For the interventions evaluated in the most trials, assessments of potential publication bias varied. Funnel plot asymmetry was present in trials of exercise therapy [36], was not present in trials of spinal manipulation [15] or behavioral therapy [32], and could not be reliably interpreted for trials of acupuncture [16]. Finally, we did not include cost-effectiveness analyses. Although many noninvasive interventions for chronic low back pain appear to have similar effects on clinical outcomes, other factors, such as cost or convenience, may vary widely. However, systematic reviews of economic analyses of low back pain interventions have found few full cost-effectiveness analyses and important methodological deficiencies in the available cost studies [185–188].
We also identified several research gaps that limited our ability to reach more definitive conclusions about optimal use of the interventions included in this review. We found no trials on optimal sequencing of interventions, and only limited evidence on methods to guide selection of therapy for individual patients. Although initial studies are promising, decision tools and other methods for individualizing and selecting optimal therapy are still in fairly early stages of development [156]. More research on methods for selecting optimal therapy that are practical for use by primary care clinicians is urgently needed. We also found few trials assessing efficacy of adding one noninvasive intervention to another. Although several trials found acupuncture plus another therapy to be more effective than the other therapy alone, other trials found little or no additional benefit from adding exercise therapy [36], behavioral interventions [33], or spinal manipulation [134] to other therapies. Finally, few trials specifically evaluated patients with sciatica (Appendix Table 12) or spinal stenosis. One systematic review of interventions for sciatica identified only 8 trials of therapies included in this review [70]. Most trials included in our review enrolled mixed populations of patients with or without sciatica, or did not enroll patients with sciatica. It remains unclear whether optimal nonpharmacologic treatments for sciatica or spinal stenosis differ from those for nonspecific low back pain, although in the case of spinal manipulation, presence or absence of radiating pain did not appear to affect conclusions [55].
In summary, evidence of effective nonpharmacologic therapies for acute low back pain is quite limited. This is not surprising, as the natural history of acute low back pain is for substantial early improvement in most patients [125]. On the other hand, several noninvasive therapies seem to be similarly effective for chronic low back pain. Although evidence on effectiveness of therapies specifically for subacute low back pain is sparse [125], many trials enrolled mixed populations of patients with subacute and chronic low back pain. Factors to consider when choosing among noninvasive therapies are patient preferences, cost, convenience, and availability of skilled providers for specific therapies. Clinicians should avoid interventions not proven effective, as many therapies have at least fair evidence of moderate benefits.
