Evaluation of Acute Low Back Pain An Evidence-Based Approach Harlan R. Ribnik, M.D., F.I.P.P. Diplomate, American Board of Anesthesiology Subspecialty Certified in Pain Medicine Diplomate, American Board of Interventional Pain Physicians
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What is Pain? The International Association for the Study of Pain says it is "an unpleasant sensory and emotional experience in association with actual or potential tissue damage, or described in terms of such damage."
Is it Back Pain? Lumbar Spinal Pain Is perceived as arising anywhere within a region bounded superiorly by an imaginary transverse line through the tip of the last thoracic spinous process, inferiorly by an imaginary transverse line through the tip of the first sacral spinous process, and laterally by vertical lines tangential the lateral borders of the lumbar erectores spinae. Pain Consultants of the Rockies, PC 4
Is it Back Pain? Sacral Spinal Pain Is perceived as arising anywhere within a region bounded superiorly by an imaginary transverse line through the tip of the first sacral spinous process, inferiorly by an imaginary transverse line through the posterior sacrococcygeal joints and laterally by imaginary lines passing through the posterior superior and posterior inferior iliac spines. Pain Consultants of the Rockies, PC 5
Is it Back Pain? Lumbosacral Pain Is perceived as arising from a region encompassing or centered over the lower third of the lumbar region, as described above, and the upper third of the sacral region as described above. Pain Consultants of the Rockies, PC 6
Is It Back Pain? Pain Consultants of the Rockies, PC 7
Pain Acuity Acute Present < 3 months Subacute 5-7 weeks up to 12 weeks Chronic Present at least 3 months Pain Consultants of the Rockies, PC 8
Referred Pain Pain perceived in a region innervated by nerves other than the ones that innervate the actual source of the pain. Visceral Referred Pain. e.g. uterus, abdominal aorta, pancreatitis. Somatic Referred Pain. e.g. Z-joints, Discs, S-I joint Pain Consultants of the Rockies, PC 9
Referred Pain Pain Consultants of the Rockies, PC 10
Referred vs. Radicular Pain Somatic Pain Can be referred distal to knee Deep, dull ache Distributed in wide areas Tends to stay in same location, may wax and wane Radicular Pain Shooting, lancinating, electrical Distributed in a narrow band Travels into lower limb Pain Consultants of the Rockies, PC 11
Natural History UK, Netherlands, USA Patients are likely to recover Median time to recover = 7 weeks Relapses are common Status of patient at 2 months indicative of that at 12 months Up to 80% disabled to some degree (10-15% severely) Lost to follow-up, probably not recovered Pain Consultants of the Rockies, PC 12
Natural History Australia Up to 70% can expect to recover and remain so at 12 months. Lower risk of recurrence. (Study excluded Workers Compensation) Pain Consultants of the Rockies, PC 13
Prognostic Risk Factors Predict Chronicity. Biologic and Psychosocial Factors Biologic Factors immutable and remediable. Age, gender, race Fractures, infections, e.g. Muscle weakness, immobility, lack of fitness Psychosocial Factors immutable and remediable Personality type, Hx Psych distress. Socioeconomic status, intelligence, job dissatisfaction, education Beliefs, cognitions, fears Pain Consultants of the Rockies, PC 14
Prognostic Risk Factors for Chronic Back Pain Pain Consultants of the Rockies, PC 15
Predictors of Chronicity Cardinal Risk Factors Hx low back pain Dissatisfaction with current job Widespread Pain Radiating leg pain Restriction in 2 or more spinal movements gender Pain Consultants of the Rockies, PC 16
Predictors of Chronicity Percentages of Patients who Become Chronic Based on Number of Cardinal Risk Factors: 0-2 6% 3-4 27-35% 5-6 - 70% Pain Consultants of the Rockies, PC 17
History Chief Complaint Length of Illness Site of Pain Location and Extent of Spread Quality Severity Frequency Is it really Back Pain? Establish Acuity Record Primary site Referred vs. Radicular Somatic vs. Radicular Baseline pain score Not of Dx value Pain Consultants of the Rockies, PC 18
History Duration Time of Onset Mode of Onset Precipitating Factors Aggravating Factors Relieving Factors Associated Features Not of Dx value Beware Night Pain! Beware Sudden Severe! Not of Dx value Absent Mech Aggravations Not of Dx value Source of most signif Dx features Pain Consultants of the Rockies, PC 19
History Red Flag Conditions Fractures, Infections, Tumors Rare Hx and P.E. Special Tests may miss these early on Pain Consultants of the Rockies, PC 20
History Red Flag Conditions Cancer Past Hx Cancer Age > 50 Prolonged illness Failure to improve with treatment Unexplained weight loss Pain Consultants of the Rockies, PC 21
History Red Flag Conditions Fractures Major trauma Minor trauma in Age > 50 Osteoporosis Corticosteroids Pain Consultants of the Rockies, PC 22
History Red Flag Conditions Spinal Infection Fever History of body penetration Diabetes mellitus Pain Consultants of the Rockies, PC 23
History Red Flag Conditions Consider MRI imaging if the patient has the Alerting Features for Cancer or an ESR > 50 Pain Consultants of the Rockies, PC 24
Physical Examination Although this process may be conventional and whereas it serves to provide a description of the patient, the existing evidence base shows that no particular clinical sign, or combination of signs, found by this process, allows a valid or reliable diagnosis of back pain to be made in anatomical or pathological terms. - Bogduk N, McGuirk B. Chapter 7, Physical Examination. Medical Management of Acute and Chronic Low Back Pain, An Evidence-Based Approach Pain Research and Clinical Management, Vol. 13 2002 Elsevier Science B.V. Pain Consultants of the Rockies, PC 25
Physical Examination Inspection Reliable for identifying structural anomalies No bearing on Dx of cause of low back pain Palpation Reproduction of pain lacks reliability and validity Range of Motion Limitations or guarding do not imply any specific Dx Pain Consultants of the Rockies, PC 26
Physical Examination Intervertebral Motion Poor agreements on estimates of intersegmental motion McKenzie Reliability varies Marginally effective as a diagnostic test Sacroiliac Joint Testing lacks validity, 25% false positives! Pain Consultants of the Rockies, PC 27
Physical Examination Normal Examination In the face of spinal pain, should alert examiner to possible Red Flag Conditions Pain Consultants of the Rockies, PC 28
Physical Examination Neurologic Examination Back Pain only No neuro Sx Somatic Referred Pain If in doubt, do the exam Radicular Pain Do Neuro exam Neurological Symptoms Exam mandatory Pain Consultants of the Rockies, PC 29
Radiographic Examination Plain Film Indications Age > 50 Significant trauma Neurological deficit Weight loss Suspect ankylosing spondylitis Drug or alcohol abuse History cancer Corticosteroid use Temp > 37.8C No improvement in 1 month Seeking compensation Pain Consultants of the Rockies, PC 30
Radiographic Examination CT Scan No place in investigation of low back pain of unknown origin MRI Scan Expensive, may reveal HNP Not for acute LBP Bone Scan Suspected infection Incipient Fx pars interarticularis Pain Consultants of the Rockies, PC 31
Algorithm For management of Acute Low Back Pain Pain Consultants of the Rockies, PC 32
Questions? Contact us at Harlan Ribnik, M.D. Pain Consultants of the Rockies, PC 307-633-8100 307-633-8108 (fax) 4136 Laramie St Cheyenne, WY 82001 Pain Consultants of the Rockies, PC 33
Questions? Contact us at Harlan Ribnik, M.D. Pain Consultants of the Rockies, PC 307-633-8100 307-633-8108 (fax) 4136 Laramie St Cheyenne, WY 82001 Pain Consultants of the Rockies, PC 34