Back Pain: If, when, and Why to imaging

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1 Back Pain: If, when, and Why to imaging L I N D A H A, D O, F A C P A S S O C I A T E P R O F E S S O R I N T E R N A L M E D I C I N E, N E O M E D A S S O C I A T E D I R E C T O R I N T E R N A L M E D I C I N E C E N T E R, S U M M A H E A L T H S Y S T E M. C L I N I C A L A S S O C I A T E P R O F E S S O R I N T E R N A L M E D I C I N E, O H I O U N I V E R S I T Y H E R I T A G E C O L L E G E O F O S T E O P A T H I C M E D I C I N E. ( H A S U M M A H E A L T H. O R G ) Course Objectives Review the American College of Physician (ACP) High-value care Choose Wisely recommendations on back pain imaging. Discuss when imaging is appropriate in the evaluation of back pain. Review which imaging modalities are best for back pain. Highlight what MKSAP 16 and 17 emphasized for Internal Medicine Board. Pretest: Low Back pain Question 1: Massage therapy may be helpful for subacute or chronic low back pain. A. (a) True B. (b) False 50% 50% :10 (a) True (b) False 1

2 Lumbar spine radiography is helpful to assess for possible malignancy or compression fracture. 50% 50% A. (a) True B. (b) False (a) True (b) False :10 Question 3: MRI of sacroiliac joints is better than CT in diagnosis ankylosing spondylitis in early disease. A. (a) True B. (b) False 50% 50% :10 (a) True (b) False Back Pain: History and Epidemiolgy 5 th most common reason for all physician visits in the U.S. 25% U.S. adults had low back pain in the last 3 months. 1998, direct health care cost $26 million. More than 85% of low back pain in primary care setting cannot be reliably attributed to specific disease or spinal abnormalities ( non specific ) 2

3 April 30, Since the Vietnam war, non-battle related injuries (NBI) are the leading cause of soldier attrition. Low back pain is one of the principal reasons soldiers seek medical attention. Attributed to psychopathologic and psychosocial stressors, low job satisfaction, and other work related factors (lack of autonomy, inadequate support structure). Only 5% of back injuries in soldiers attributed to combat operations. Women soldiers were more likely to return to duty after back injury compared to men (22% versus 12% in men). HVC Low Back Pain Imaging Recommendations: ACP NASS High Value Care (HCV) ACEP AANS and CNS AAPM&R HVC Recommendations for Low Back Imaging American College of Physician (ACP) Don t obtain imaging studies in patients with non-specific low back pain. American College Emergency Physician (ACEP) Avoid lumbar spine imaging in the ER for adults with non-traumatic back pain unless the patient has severe or progressive neurological deficits OR is suspected of having serious underlying condition (such as vertebral infection, cauda equina syndrome, or cancer with bony metastasis). 3

4 HCV Recommendations for Low Back Imaging (cont.) American Academy of Physical Medicine and Rehabilitation (AAPM&R): Don t order an EMG for low back pain unless there is leg pain or sciatica. Don t order an imaging study for back pain without performing a thorough physical exam. American Association of Neurological Surgeons (AANS) and Congress of Neurological Surgeons (CNS): Don t obtain imaging (plain xrays, MRI, CT or other advanced imaging) of the spine in patients with non-specific acute low back pain and without red flags. HVC Recommendations for Low Back Imaging (cont.) North American Spine Society (NAS): Don t recommend advanced imaging (eg. MRI) of the spine within the first 6 weeks in patients with non-specific acute low back pain in the absence of red flags. National Institute for Health and Care Excellence (NICE) Guideline: Key Points Published May 27, 2009 (nice.org.uk/guidance/cg88) Do not offer X-ray of the lumbar spine for management of nonspecific low back pain. Consider MRI for diagnosis of spinal malignancy, infection, fracture, cauda equina syndrome or ankylosing spondylitis or another inflammatory disorder is suspected. Only offer MRI for non-specific low back pain within context of a referral for an opinion on spinal fusion. 4

5 HIGH VALUE CARE for Back pain...take home points. NASS ACP High Value Care (HCV) ACEP Don t do imaging for nonspecific back pain. Look for red flag and neurological signs. No imaging if less than 6 weeks of symptoms. Consider imaging if severe or progressive symptoms. AANS and CNS AAPM&R Back Pain WHEN SHOULD WE BE WORRIED AND WHEN TO ORDER IMAGING? Approach to Back pain Duration of symptoms Distribution of the pain Age of the patient CLEV CLIN J MED 1995;62:

6 Duration of symptoms Distribution of the Pain Acute back pain: less than 4 weeks. Subacute: 4-12 weeks. Chronic: more than 12 weeks. Leg pain: below knee suggestive of true sciatica Absence of leg pain points to non-sciatica possibilities. Age of patient Age over 50: greater risk for serious nonmechanical sources Disk herniation and sciatica: peak age years. CLEV CLIN J MED 1995;62: Back Pain Imaging: Relying on the history Back Pain Imaging: Relying on the history Location, Character and when pain occurs. History of cancer, trauma or HIV. Smoking and IV drug use. 6

7 Back Pain and Intravenous Drug Abuse: Challenging Diagnosis IVDU is an independent risk factor for pyogenic spine infection due to lymphocyte opiate receptor mediated natural killer T-lymphocyte inactivation. Fever, chills and increased WBC are not always present on presentation: Only 1/3 had fever (greater than 37.5C) 1/3 will not have increased WBC. Blood cultures only positive in 30%. Approximately 30% had mild neurological symptoms. 2 weeks delay on plain x-ray on presentation of symptoms. Average delay from initial presentation to diagnosis is 2.7 months. Back Pain: Relying on Physical Exam Back Pain: Physical exam Muscle weakness, absent sphincter control, saddle anesthesia. 7

8 Back Pain: The Physical Exam Positive tension sign: sciatic pain with passive elevation between 30 and 60 o. 80% sensitive for disk herniation with L5 or S1 radiculopathy. Back Pain: Motor and Sensory testing Toe-walk: S1 nerve root. Heel-walk: L4-L5 nerve root involvement. Inability to squat: L4 nerve root involvement. Back Pain: Motor and Sensory testing L3-L4 disc herniation: pain, parethesia, numbness, hypalgesia in anteromedial thigh and knee. L4-L5 disc: numbness or paresthesia in anterolateral calf, great toe, first web space and medial foot. L5-S1: numbess and hypalgesia of fifth toe, lateral aspect of foot, sole, posterolateral calf and thigh. 8

9 Back Pain Imaging: The physical exam Waddell s signs: 3 or more signs may suggestive malingering/non-organic causes. Caudal equina syndrome: associated with massive midline shift disc herniation. Rare; prevalence 0.04% among patients with low back pain. Urinary retention most frequent finding (90% sensitivity). Straight leg raise testing, knee strength and reflexes, great toe and foot dorsiflexion strength, foot plantarflexion and ankle reflexes are all supportive maneuvers. Waddell s Nonorganic Physical Signs Presence of 3 or more response suggests non-organic and psychosocial issues to back pain. Back Pain Imaging WHICH MODALITY IS BEST? 9

10 Back Pain: Plain Xrays osteoporosis/osteopenia compression fracture DISH (Bridging osteophytes) Back pain: low velocity trauma, osteoporosis, elderly or chronic steroid use. MRI without contrast Back pain ACR Appropriateness Criteria 2015 X-Ray lumbar spine CT without contrast Back pain: suspicion for cancer, infection, or immunosuppression Suspect widespread tumor or multifocal metastasis Tc-99m Bone Scan whole body with SPECT Back pain Suspect neoplasia with epidural or intraspinal disease Low risk of epidural and/or intraspinal disease MRI with/without contrast MRI without contrast FDG-PET/CT whole body helps distinguish benign versus malignant compression fractures If MRI contraindicated or not available CT with or without contrast X-ray lumbar spine ( ) ACR Appropriateness Criteria

11 Back pain: surgical candidate of after 6 weeks of conservative therapy MRI without contrast Contrast MRI is indicated if prior back surgery Back pain If MRI contraindicated or not available CT without or without contrast X-ray Myelography and post myelography CT lumbar spine ACR Appropriateness Criteria 2015 High Value Care (HCV): What you need to know in MKSAP 17 Evaluate acute, nonspecific back pain. Key Point: Imaging or other diagnostic tests should not be routinely obtained in patients with nonspecific back pain. nonspecific back pain is defined as: low back pain that cannot be attributed to a specific disease or spinal abnormality. Treat subacute, nonspecific low back pain. Key Point: Massage therapy is likely helpful with subacute or chronic symptoms and no abnormal neurological findings. Acute, Subacute and Chronic classifications: Acute: less than 4 weeks Subacute: 4-12 weeks Chronic: more than 12 weeks Low Back pain in 67-yr old male Diffuse idiopathic skeletal hyperostosis is confirmed on radiograph by the presence of flowing osteophytes along the anterolateral aspect of at least four contiguous vertebral bodies. 11

12 References National Institute for Health and Care Excellence (NICE) Guidelines. Nice.org.uk/guidance/cg88 Cohen SP, Nguyen C, Kapoor SG et al. Back Pain During War. An analysis of factors affecting outcome. Arch Intern Med. 2009;169(20): Wang Z, Lenhan B, Itshayek E et al. Primary pyogenic infection of the spine in intravenous drug users. Spine 2012;37: Greer S, Chambliss L. What physical exam techniques are useful to detect malingering? Journal of Family Practice. Vol 54(7). August Chou R, Qaseem A, Snow V, et al. Diagnosis and treatment of low back pain: A Joint Clinical Practice guideline from the American College of Physicians and the American Pain Society. Ann Intern Med. 2007; 147: Chuo CC, Fu Y, Lue Y, et al. Spinal Infection in Intravenous Drug Users. J Spinal Disord Tech 2007;20: References (cont) Klineberg E, Mazanec D, Orr D et al. Masquerade: Medical causes of back pain. Cleve Clin J Med 2007 (Dec);74(12): Mazanec D. Back pain: medical evaluation and therapy. Cleve Clin J Med 1995;62: Bhangle S, Sapru S, Panush R. Back pain made simple: An approach based on principles and evidence. Cleve Clin J Med 2009 (Jul); 76(7):