Roger Chou, MD John Loeser, MD Rick Rosenquist, MD Steve Stanos, DO (moderator)

Transcription

1 Evidence-based Medicine for Evaluation and Management of Low Back Pain: Update on Guidelines from the American Pain Society Richard W. Rosenquist, MD For the American Pain Society Low Back Pain Guidelines Project May 8, 2008 Acknowledgments OHSU EPC Pain Project Team: Laurie Huffman, Michelle Pappas, Jayne Schablaske APS/ACP LBP Panel: Co-chairs - John Loeser, Doug Owens, Richard W. Rosenquist APS: Christine Miaskowski, Cathy Underwood ACP: Amir Qaseem CEAS, Vincenza Snow VA/DoD: Carla Cassidy, Oded Susskind, VA/DoD Evidence-based Practice Workgroup 2 May 8, 2008 Conflict of interest disclosure Chou: Bayer Pharmaceuticals (honorarium) Loeser: Medtronic, Elan, Endo, Pfizer, Xenoport (consultant for all) Rosenquist: Arrow International, Altea Therapeutics, Medtronic (consultant); Celgene (research support) Stanos: Abbott Labs, Alpharma, Endo, Pfizer (consultant); Alpharma, Cephalon, Ortho-McNeil Pharm, Pfizer (speaker); Abbott Labs (research support) 3 May 8,

2 Purpose Describe methods for assessing and synthesizing evidence for clinical practice guidelines Explain evidence-based recommendations for: initial evaluation of low back pain non-interventional management of low back pain use of interventional therapies and surgery for low back pain 4 May 8, 2008 Low back pain burden Low back pain is the 5 th most common reason for U.S. office visits, and the 2 nd most common symptomatic reason About ¼ of U.S. adults report low back pain lasting a whole day in the last 3 months About 7.6% report severe low back pain in last year (about one third sought medical care) $90.7 billion dollars in total health care expenditures in 1998 Low back pain is the most common cause for activity limitations in persons under the age of 45 5 May 8, 2008 Challenges in low back pain Unexplained practice variations Numerous treatment options Use of unproven treatments Natural history of acute low back pain Precise anatomic diagnosis often not possible Effects of interventions in trials are only moderate on average 6 May 8,

3 Experts on effectiveness of treatments for low back pain Mobilization and manipulation studies claim an 80% success rate. 80% of low back pain patients get immediate relief with epidural blocks. In the YMCA s exercise program, 80% improve. With microcurrent therapy 82% were pain free with 10 treatments % of those carefully screened for radicular symptoms benefit from surgery. Deyo RA, Spine 1993;18: May 8, Back Pain Breakthroughs Are you hurting? Here's help. By Michael J. Weiss From Reader's Digest July 2007 End Back Pain Agony 8 May 8, 2008 Reader s Digest Cures for LBP All cures based on anecdotal evidence, not yet approved, and/or only animal studies Spinal cord stimulator Infrared belt - $2,335 Magic Spinal Wand Percutaneous automatic discectomy Flexible fusion Stem cells Site-directed bone growth New bed Based on an observational study funded by a sleep products trade group 9 May 8,

4 Experts on causes of low back pain 80% of back pain is caused by weak or tense muscles. The majority of LBP actually originates in the sacral ligaments. In 50% or more the facet joint is the site of dysfunction % of back pain is due to disks. An extremely high percentage have fascial problems % of chronic symptoms are psychological in origin. Deyo RA, Spine 1993;18: May 8, 2008 Parade Magazine You can help your backache Dr. Isadore Rosenfeld, October 24, 2004 If the low back pain continues beyond three days, see a doctor. Get a targeted physical exam and an X-ray of your back to determine whether the vertebrae are aligned properly, fractured, or significantly worn or damaged May 8, 2008 What are clinical practice guidelines? Systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances. Institute of Medicine, May 8,

5 APS/ACP Low Back Pain Guidelines Project Began 2004, primary care guidelines published October 2007 Guidelines address both acute and chronic LBP, and nonspecific LBP and LBP with radiculopathy or spinal stenosis Guidelines for interventional therapies/surgery planned for 2008 Formal partnership between the the Funded by the American Pain Society Multidisciplinary panel with 25 members, over 15 specialties/organizations represented Series of 3 face-to-face meetings to develop guidelines Consensus achieved for all recommendations 13 May 8, 2008 Methods for developing APS/ACP guidelines Scope and series of key questions developed by expert panel to guide systematic evidence review Pre-specified methods for ranking evidence, evaluating balance of benefits and harms, and grading strength of recommendations Consensus/voting process Peer review by over 40 external experts Approval by APS Executive Committee and ACP Board of Regents 14 May 8, 2008 Definitions for estimating magnitude of effects Size of effect Small/ slight Moderate Large Definition 5-10 point improvement on a 100 point scale SMD 0.2 to point improvement on a 100 point scale SMD 0.5 to 0.8 >20 point improvement on a 100 point scale SMD > May 8,

6 Recommendation grid Adapted from USPSTF methods Net benefit Quality of evidence Substantial Moderate Small Zero/ negative Good A B C D Fair Poor B B C D I I I I 16 May 8, 2008 Recommendation grid ACP Methods Quality of evidence Benefits do or do not clearly outweigh risks Strength of recommendation Benefits and risks and burdens finely balanced High Strong Weak Moderate Strong Weak Low Strong Weak Insufficient I 17 May 8, 2008 Search results Over 8000 citations reviewed Over 200 relevant systematic reviews, over 130 included Over 170 additional studies not included in systematic reviews 18 May 8,

7 Basic principles of low back pain management History and physical exam to exclude red flag symptoms suggestive of serious underlying pathology Physical exam for neurologic screening Consideration of psychosocial factors Diagnostic triage into broad categories Judicious use of diagnostic imaging Use interventions with proven efficacy Non-invasive approaches to most LBP 19 May 8, 2008 Recommendation 1 Clinicians should conduct a focused history and physical examination to help place patients with low back pain into one of three broad categories: non-specific low back pain, back pain potentially associated with radiculopathy (nerve disorders) or spinal stenosis (narrowing), or back pain associated with another specific cause. The history should include assessment of psychosocial risk factors, which predict risk for chronic disabling back pain. (strong recommendation, moderate-quality evidence) 20 May 8, 2008 Epidemiology of low back pain >85% of patients who present to primary care have LBP that cannot be attributed to a specific disease or spinal pathology No evidence that labeling most patients with specific diagnosis improves outcomes Cancer 0.7%, compression fracture 4%, ankylosing spondylitis 0.3% to 5%, spinal infection 0.01% Spinal stenosis 3%, symptomatic herniated disc 4% Cauda equina syndrome 0.04% (usually due to massive midline disc herniation) 21 May 8,

8 History and physical for diagnosing cancer Cancer: History of cancer, elevated ESR Weaker predictors unexplained weight loss, failure to improve after 1 month, age >50 Herniated disc: Typical history and straight leg raise Spinal stenosis: Wide-based gait, lack of pain when seated Weaker predictors neurogenic claudication, age >65 Cauda equina syndrome: Urinary retention 22 May 8, 2008 Assessing yellow flags Yellow flags = features of history or physical associated with development of chronic disabling LBP Psychosocial distress, unresolved compensation issues, somatization all associated with poor LBP outcomes Two recent trials found primary care interventions to identify and treat yellow flags ineffective 23 May 8, 2008 Recommendation 2 Clinicians should not routinely obtain imaging or other diagnostic tests in patients with nonspecific low-back pain. (strong recommendation, moderate-quality evidence) 24 May 8,

9 Do not routinely obtain imaging or other diagnostic tests No evidence that routine plain radiography improves patient outcomes (3 RCTs) Lumbar x-rays result in as much gonadal radiation in women as a daily CXR for more than a year More advanced imaging also does not improve outcomes and may lead to additional, possibly unnecessary, interventions 25 May 8, 2008 Recommendation 3 Clinicians should perform diagnostic imaging and testing for patients with low back pain when severe or progressive neurologic deficits are present or when serious underlying conditions are suspected. (strong recommendation, moderatequality evidence) 26 May 8, 2008 When to obtain imaging and other diagnostic tests High risk for vertebral compression fracture Suspected infection, cauda equina syndrome, progressive/severe neurologic deficits Advanced imaging usually necessary Risk factors for cancer If age only risk factor, consider time-limited (e.g. 1 month) trial of therapy If previous cancer or cancer more strongly suspected, consider x-ray plus ESR initially 27 May 8,

10 Recommendation 4 Clinicians should evaluate patients with persistent low-back pain and signs or symptoms of radiculopathy or spinal stenosis with magnetic resonance imaging (preferred) or computed tomography only if they are potential candidates for surgery or epidural steroid injection (for suspected radiculopathy). (strong recommendation, moderate-quality evidence) 28 May 8, 2008 Diagnostic testing for suspected spinal stenosis/lumbar disc herniation Patients without severe/progressive neurologic deficits do not need routine imaging (most improve with non-specific therapies) If no improvement after >1 month of standard interventions, consider MRI or CT in patients who are candidates for surgery or epidural steroid injections 29 May 8, 2008 Low Back Pain Evaluation Algorithm, part 1 Complete algorithm can be seen in: Diagnosis and Treatment of Low Back Pain: A Joint Clinical Practice Guideline from the and the American Pain Society. Ann Intern Med. 2007;147:

11 Low Back Pain Evaluation Algorithm, part 2 31 May 8, 2008 Low Back Pain Evaluation Algorithm, continued Suggested diagnostic work-up 32 Recommendation 5 Clinicians should provide patients with lowback pain evidence-based information about their expected course, advise patients to remain active, and provide information about effective self-care options. (strong recommendation, moderatequality evidence) 33 May 8,

12 Advice and self-care for low back pain Provide all patients information about generally favorable prognosis of acute LBP with or without sciatica If no improvement, discuss need for re-evaluation Advise to remain active Consider self-care education books Superficial heat moderately effective for acute LBP No evidence to support use of lumbar supports Firm mattresses inferior to medium-firm mattresses (1 RCT) 34 May 8, 2008 General principles for choosing low back pain interventions Consider interventions with proven efficacy Consider whether acute or chronic LBP All medications associated with adverse events, little evidence on long-term benefits/harms Little evidence on efficacy of non-invasive interventions specifically in pts with spinal stenosis or radiculopathy Consider patient preferences, costs, burdens when choosing interventions 35 May 8, 2008 Recommendation 6 Clinicians should consider the use of medications with proven benefits in conjunction with back care information and self care. Clinicians should assess the severity of baseline pain and functional deficits, potential benefits, risks, and relative lack of long-term efficacy and safety data before initiating therapy. For most patients, first-line medication options are acetaminophen or NSAIDs. (strong recommendation, moderate-quality evidence) 36 May 8,

13 Pharmacologic interventions Drug Net benefit Level of evidence Acetaminophen Small to moderate Fair NSAIDs Moderate Good Skeletal muscle relaxants Tricyclic antidepressants Moderate (for acute LBP only) Small to moderate (for chronic LBP only) Good Good 37 May 8, 2008 Pharmacologic interventions (continued) Drug Net benefit Level of evidence Opioids and Moderate Fair tramadol Benzodiazepines Moderate Fair Antiepileptic medications Small (for radiculopathy only) Fair Systemic steroids No benefit Good 38 May 8, 2008 Recommendation 7 For patients who do not improve with self-care options, clinicians should consider the addition of non-pharmacologic therapy with proven benefits for low back pain. They are spinal manipulation for acute low back pain; and for chronic or sub-acute low-back pain options include: intensive interdisciplinary rehabilitation, exercise therapy, acupuncture, massage therapy, spinal manipulation, yoga, cognitivebehavioral therapy, or progressive relaxation. (weak recommendation, moderate-quality evidence) 39 May 8,

14 Non-invasive interventions for acute low back pain Intervention Spinal manipulation Net benefit Small/Moderate Fair Level of evidence Exercise therapy No benefit Good Back schools Unclear Poor 40 May 8, 2008 Non-invasive interventions for acute low back pain (continued) Intervention Net benefit Level of evidence Acupuncture Unclear Poor Massage Unclear Poor Interferential therapy, short-wave diathermy, ultrasound, lumbar supports, TENS Unclear Poor 41 May 8, 2008 Non-invasive interventions for chronic or subacute low back pain Intervention Net benefit Level of evidence Behavioral therapy Moderate Good Exercise therapy Moderate Good Interdisciplinary Moderate Good rehabilitation Spinal manipulation Moderate Good Acupuncture Moderate Fair 42 May 8,

15 Non-invasive interventions for chronic or subacute low back pain (continued) Intervention Net benefit Level of evidence Massage Moderate Fair Yoga Moderate Fair (for Viniyoga) Back schools Small Fair Traction No benefit Fair Interferential therapy, lumbar supports, short-wave diathermy, TENS, ultrasound Unclear Poor 43 May 8, 2008 Non-invasive interventions for chronic or subacute low back pain (continued) Intervention Net benefit Level of evidence EMG biofeedback Unclear Poor Low-level laser therapy Unclear Poor Lumbar supports Unclear Poor Acupressure, neuroreflexotherapy, spa therapy Not studied in U.S. Not studied in U.S. 44 May 8, 2008 Targeting interventions Being able to target specific interventions based on patient characteristics could help us get beyond modest effects Spinal palpatory tests and tests for sacroiliac joint unreliable and accuracy not established A decision rule helped predict who would benefit from spinal manipulation (1 study) Decision rule not readily usable in primary care Results may not be generalizable Tailored physical therapy more effective than standardized physical therapy (2 trials) 45 May 8,

16 Low Back Pain Algorithm - Interventions Recommended interventions 46 Challenges in developing guidelines for interventional procedures and surgery Generally small numbers of trials (with the exception of epidural steroids) Unclear utility of invasive diagnostic tests used to select patients for some of the therapies Inconsistent results between trials Increasing utilization 47 May 8, 2008 Increasing Rates of Lumbar Fusion Surgery Weinstein JN. Spine 2006; 31: May 8,

17 Increasing Rates of Back Injections Friedly J. Spine 2007; May 8, 2008 Recommendation: Invasive tests (draft) In patients with chronic non-specific LBP, provocative discography is not recommended as a procedure for diagnosing discogenic low back pain (strong recommendation, moderatequality evidence). There is insufficient evidence to evaluate validity or utility of diagnostic selective nerve root block, intra-articular facet joint block, medial branch block, or sacroiliac joint block as diagnostic procedures for low back pain with or without radiculopathy. 50 May 8, 2008 Invasive tests for low back pain Used to select patients with chronic LBP for invasive procedures targeting specific anatomic sources in the back No gold standard for distinguishing symptomatic from asymptomatic anatomic abnormalities Have not been shown to improve clinical outcomes compared to clinical assessment and non-invasive testing Provocative discography For diagnosing discogenic LBP High rate of positive tests in pts without LBP but with somatization, pain at other sites, previous disc surgery, etc. Selective nerve root blocks Facet joint/medial branch and SI joint blocks 51 May 8,

18 Recommendation: interventional therapies for non-radicular LBP (draft) In patients with persistent low back pain, facet joint corticosteroid injection, prolotherapy, and intradiscal corticosteroid injection are not recommended (strong recommendation, moderate-quality evidence). There is insufficient evidence to adequately evaluate benefits of epidural steroid injection, intradiscal electrothermal therapy, therapeutic medial branch block, radiofrequency denervation, sacroiliac joint steroid injection, or intrathecal therapy with opioids or other medications for non-specific low back pain or for non-radicular low back pain with common degenerative changes. 52 May 8, 2008 Interventional therapies for non-radicular low back pain Most interventional therapies not proven to be effective in placebo-controlled, randomized trials No trials, trials showing no benefit, or inconsistent results Promising results from non-randomized studies not replicated in randomized trials IDET Facet joint steroid injection Not clear if interventions are ineffective, or if patients are not being accurately selected for procedures targeting specific spinal structures 53 May 8, 2008 Non-spinal injections for non-specific low back pain Intervention Population Net benefit Level of evidence Local/trigger Non-specific LBP Unclear Poor point injections Botulinum toxin Non-specific LBP Unclear Poor Prolotherapy Non-specific LBP Not effective Good 54 May 8,

19 Non-spinal injections for non-specific low back pain Local injections Trials evaluated heterogeneous conditions, injection sites, and poor quality Botulinum toxin One small, short-term trial Prolotherapy Several trials consistently found no benefit Trials showing benefit included unequal cointerventions (spinal manipulation) or multiple cointerventions 55 May 8, 2008 Steroid injections for non-radicular low back pain Intervention Epidural steroids Facet joint steroid injection Intradiscal steroid injection Sacroiliac joint injection Population Spinal stenosis, non-specific LBP Presumed facet joint pain Presumed discogenic back pain Presumed sacroiliac joint pain Net benefit Unclear Not effective Not effective Unclear Level of evidence Poor Fair Good Poor 56 May 8, 2008 Steroid injections for non-radicular low back pain Epidural steroids Sparse data (one trial each) and no clear benefit for non-specific low back pain and spinal stenosis Intradiscal steroids No benefit in three trials Facet joint injection No clear benefit in two trials Uncontrolled facet joint blocks or only clinical criteria used to select patients No trials using controlled facet joint blocks Sacroiliac joint injection One small trial in patients without spondyloarthropathy Therapeutic medial branch block No trials 57 May 8,

20 Interventional therapies for non-radicular low back pain Net Level of Intervention Population benefit evidence Epidural steroids Spinal stenosis Unclear Poor Radiofrequency denervation Intradiscal electrothermal therapy Percutaneous intradiscal radiofrequency thermocoagulation Presumed facet joint pain Presumed discogenic back pain Presumed discogenic LBP 58 May 8, 2008 Unclear Unclear Not effective Poor Poor Fair IDET, PIRFT, coblation nucleoplasty Intradiscal Electrothermal Therapy (IDET) Conflicting results from three trials (highly selected populations) Percutaneous intradiscal radiofrequency thermocoagulation (PIRFT) No benefit from one trial Coblation nucleoplasty No trials 59 May 8, 2008 Radiofrequency denervation Presumed facet joint pain Conflicting results from two higher-quality trials Results uninterpretable from two other trials (one inadequate technique, one poor reporting of results) Presumed discogenic back pain One small trial 60 May 8,

21 Recommendation: Interventional therapies for radicular LBP (draft) In patients with persistent radiculopathy due to herniated intervertebral disc, clinicians should discuss risks and benefits of epidural steroid injections as an option (weak recommendation, moderate-quality evidence). Shared decision-making regarding epidural steroid injections should include a specific discussion about inconsistent evidence showing moderate short-term benefits, and lack of long-term benefits. 61 May 8, 2008 Interventional therapies for radiculopathy/prolapsed disc Level of Intervention Net benefit evidence Chemonucleolysis Moderate Good Epidural steroid injections Intradiscal steroid injection Radiofrequency denervation Moderate (short-term benefits only) Not effective Unclear Fair Fair Poor 62 May 8, 2008 Interventional therapies for radiculopathy/prolapsed disc Epidural steroid injection Short-term benefits in some higher-quality trials, but data are inconsistent (could be related to comparator used in trials) No long-term benefits No route clearly superior Chemonucleolysis More effective than placebo, but inferior to surgery Allergic reactions, not widely available in U.S. 63 May 8,

22 Surgery for chronic low back pain Few trials compare surgery to no surgery All trials enrolled patients who failed >1 year of non-surgical management and excluded patients at higher risk for poorer outcomes Surgical technique and efficacy depends on the underlying condition In general, more technically difficult/costly procedures have not been shown more effective than less difficult/cost procedures Fusion $35,000/case; instrumentation adds $6-10,000; COST/QALY >$3,000,000/QALY for instrumented vs. non-instrumented fusion 64 May 8, 2008 Recommendation: Surgery for low back pain with DDD (draft) In patients with non-radicular low back pain, common degenerative spinal changes, and persistent and disabling symptoms, clinicians should discuss risks and benefits of surgery as an option (weak recommendation, high-quality evidence). Shared decision-making regarding surgery for nonspecific low back pain should include a specific discussion about the small to moderate average benefit from surgery versus non-surgical therapies even in highly selected patients, and the fact that the majority of such patients who undergo surgery do not experience an optimal outcome (defined as minimum or no pain, discontinuation of pain medications, and return of high-level function). 65 May 8, 2008 Surgery vs. non-surgical treatment for non-radicular low back pain with DDD Intervention Population Net benefit Lumbar interbody fusion Vertebral disc replacement Non-radicular, presumed discogenic LBP Presumed discogenic LBP Not effective vs. intensive rehabilitation (3 trials), more effective than standard physical therapy (1 trial) No difference vs. fusion Level of evidence Good Fair (2 trials) 66 May 8,

23 Surgery for non-radicular low back pain with DDD Fusion appears superior to continued standard non-surgical therapy, but no better than intensive interdisciplinary rehabilitation Benefits vs. standard non-surgical therapy average less than 15 points on a 100 point scale for pain or function Even in highly selected patients, fewer than half experience optimal outcomes (relief of pain, return to work, decreased analgesic use) No evidence that instrumentation improves clinical outcomes 67 May 8, 2008 Recommendation: Artificial disk replacement (draft) In patients with non-radicular low back pain, common degenerative spinal changes, and persistent and disabling symptoms, there is insufficient evidence to adequately evaluate long-term benefits and harms of vertebral disc replacement (insufficient evidence). 68 May 8, 2008 Artificial disk replacement Artificial disk replacement similar to fusion in two trials Long-term outcomes/complications after disk replacement unknown Trials only enrolled patients with one or two level degenerative disc disease 69 May 8,

24 Recommendation: Surgery for herniated disc and spinal stenosis (draft) In patients with persistent and disabling radiculopathy due to herniated lumbar disc or persistent and disabling leg pain due to spinal stenosis, clinicians should discuss risks and benefits of surgery as an option (strong recommendation, high-quality evidence). Shared decision-making regarding surgery should include a specific discussion about moderate average benefits in patients who undergo surgery, which appear to decrease over time. 70 May 8, 2008 Surgery versus non-surgical treatment for prolapsed lumbar disc and spinal stenosis Intervention Population Net benefit Decompressive laminectomy Interspinous spacer Discectomy Level of evidence Spinal stenosis Moderate Good (4 trials) Spinal stenosis Moderate Fair (2 trials) Prolapsed lumbar disc Moderate (mostly short-term) Good (4 trials) 71 May 8, 2008 Surgery for herniated disc with radiculopathy Discectomy associated with more rapid improvement in symptoms than non-surgical therapy Patients improved either with or without surgery No progressive neurologic deficits without surgery Long-term (after 2 years) outcomes similar Most trials on open discectomy or microdiscectomy; little evidence on percutaneous, laser-assisted, and other minimally invasive approaches 72 May 8,

25 Surgery for spinal stenosis Surgery for spinal stenosis (with or without degenerative spondylolisthesis) Decompressive laminectomy associated with superior outcomes versus non-surgical therapy Only mild improvement with non-surgical therapy Benefits may decrease with long-term (>5 years) followup Interspinous spacer device associated with superior outcomes versus non-surgical therapy for one- or two-level spinal stenosis with symptoms relieved with flexion Two trials, no comparison to laminectomy 73 May 8, 2008 Recommendation: Spinal cord stimulation for failed back surgery syndrome (draft) In patients with persistent and disabling radicular pain following discectomy and who do not have evidence of a persistently compressed nerve root, clinicians should discuss risks and benefits of spinal cord stimulation as an option (weak recommendation, moderate-quality evidence). Shared decision-making regarding spinal cord stimulation should include a specific discussion about the high rate of complications following spinal cord stimulator placement. 74 May 8, 2008 Spinal cord stimulation No trials except for failed back syndrome with persistent radiculopathy Spinal cord stimulation superior to repeat surgery 1 trial Spinal cord stimulation superior to conventional medical management in 1 trial 26-32% device-related complications 75 May 8,

26 Research gaps We need more and higher-quality studies to better apply evidence based medicine to low back pain treatment More research needed on methods for tailoring treatment to individual patients More research needed on sequencing of interventions and combining interventions No data demonstrating utility of invasive diagnostic tests 76 May 8, 2008 Research gaps (continued) Little data showing effectiveness of interventions for presumed facet joint pain, sacroiliac joint pain, discogenic LBP Sparse data on harms for most interventions Sparse data on long-term effects for most interventions Sparse data on efficacy of non-invasive interventions for spinal stenosis or prolapsed lumbar disc 77 May 8,