• Bradley WG Jr, Seidenwurm DJ, Brunberg JA, Davis PC, DE La Paz RL, Dormont D, Hackney DB, Jordan JE, Karis JP, Mukherji SK, Turski PA, Wippold FJ, Zimmerman RD, McDermott MW, Sloan MA, Expert Panel on Neurologic Imaging. Low back pain. [online publication]. Reston (VA): American College of Radiology (ACR); 2005. 7 p. [23 references]

This is the current release of the guideline.

This guideline updates a previous version: Anderson RE, Drayer BP, Braffman B, Davis PC, Deck MD, Hasso AN, Johnson BA, Masaryk T, Pomeranz SJ, Seidenwurm D, Tanenbaum L, Masdeu JC. Acute low back pain--radiculopathy. American College of Radiology. ACR Appropriateness Criteria. Radiology 2000 Jun;215(Suppl):479-85.

The appropriateness criteria are reviewed annually and updated by the panels as needed, depending on introduction of new and highly significant scientific evidence.

ACR Appropriateness Criteria®

Clinical Condition: Acute Low Back Pain

Variant 1: Uncomplicated. No red flags. (Red flags defined in the text below.)

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 2: Low velocity trauma, osteoporosis, and/or age > 70.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 3: Suspicion of cancer, infection, or immunosuppression.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 4: Radiculopathy.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 5: Prior lumbar surgery.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Variant 6: Cauda equina syndrome.

Note: Abbreviations used in the tables are listed at the end of the "Major Recommendations" field.

Acute low back pain (LBP) with or without radiculopathy (pain radiating down the leg[s]) is one of the most common health problems in the United States and is the leading cause of disability for persons younger than age 45. The cost of evaluating and treating acute LBP runs into billions of dollars annually, not including time lost from work.

Because of the high prevalence and high cost of dealing with this problem, government agencies have sponsored extensive studies that are now part of the growing body of literature on this subject. One of the earlier comprehensive studies was carried out in Quebec and was reported in the journal Spine in 1987. The U.S. Department of Health and Human Services convened a 23-member multidisciplinary panel of experts to review all of the literature on this subject, grade it, and develop a "Clinical Practice Guideline," which was published in December 1994. States have also convened similar panels in recent years, largely because of the rapidly rising workers' compensation claim burden being imposed on state budgets by LBP management.

It is now clear from the above studies that uncomplicated acute LBP is a benign, self-limited condition that does not warrant any imaging studies. The vast majority of these patients are back to their usual activities within 30 days. The challenge for the clinician, therefore, is to distinguish that small segment within this large patient population that should be evaluated further because of suspicion of a more serious problem.

Indications of a more complicated status, often termed "red flags," include the following:

1. Recent significant trauma, or milder trauma, age >50
2. Unexplained weight loss
3. Unexplained fever
4. Immunosuppression
5. History of cancer
6. Intravenous (IV) drug use
7. Prolonged use of corticosteroids, osteoporosis
8. Age >70
9. Focal neurologic deficit progressive or disabling symptoms
10. Duration greater than 6 weeks

Radiographs:

Radiographs are recommended when any of the above red flags are present. Lumbar radiography may be sufficient for the initial evaluation of these red flags:

1. Recent significant trauma (at any age)
2. Osteoporosis
3. Age >70

The initial evaluation of the LBP patient may require further imaging if red flags such as suspicion of cancer or infection are present.

Isotope Bone Scan

The role of the isotope bone scan in patients with acute LBP has changed in recent years with the wide availability of MRI and especially contrast-enhanced MRI. The bone scan is a moderately sensitive test for detecting the presence of tumor, infection, or occult fractures of the vertebrae but not for specifying the diagnosis. The yield is very low in the presence of normal radiographs and laboratory studies and highest for patients with known malignancy. The test is contraindicated in pregnancy.

High-resolution isotope imaging including single photon emission computed tomography (SPECT), may localize the source of pain in patients with articular facet osteoarthritis prior to therapeutic facet injection. Similar scans may be helpful in detecting and localizing the site of painful pseudoarthrosis in patients following lumbar spinal fusion.

Plain and contrast-enhanced MRI has the ability to demonstrate inflammatory, neoplastic, and most traumatic lesions as well as show anatomic detail not available on isotope studies. Gadolinium-enhanced MRI reliably shows the presence and extent of spinal infection, and is useful in assessing therapy. MRI has therefore taken over the role of the isotope scan in many cases where the location of the lesion is known. The isotope scan remains invaluable when a survey of the entire skeleton is indicated (e.g., for metastatic disease).

Magnetic Resonance Imaging, Computed Tomography (CT), Myelography, Myelography/CT

Uncomplicated acute LBP (no red flags) does not warrant the use of any of this imaging studies. The early indiscriminate use of expensive imaging procedures in this common clinical setting has caused large increases in worker's compensation costs and in some cases has led to the perception that CT and MRI of the lumbar spine are not worth the cost. Adding to this controversy is the fact that nonspecific lumbar disc abnormalities are common, and can be demonstrated readily on myelography, CT, and MRI, even in asymptomatic patients.

The appropriate use of these imaging procedures is an important challenge that has been extensively addressed in the major reviews referenced herein (see the original guideline). For example, LBP complicated by "red flags" suggesting infection or tumor may justify early use of CT or MRI even if radiographs are negative. The most common indication for the use of these imaging procedures, however, is the clinical setting of LBP complicated by radiating pain (radiculopathy, sciatica) or cauda equina syndrome (bilateral leg weakness, urinary retention, saddle anesthesia), usually due to herniated disc and/or canal stenosis.

Magnetic Resonance Imaging

MRI of the lumbar spine has become the initial imaging modality of choice in complicated LBP, displacing myelography and CT in recent years. MRI is particularly efficacious for detecting "red flag" diagnoses, particularly using the STIR and fat-saturated T2 fast-spin-echo sequences. MR with contrast is useful for suspected infection and neoplasia. In postop patients, enhanced MRI allows distinction between disc and scar when there is extension of tissue beyond the interspace.

Computed Tomography

CT scans provide superior bone detail but are not quite as useful in depicting disc protrusions when compared with multiplanar MRI. With the added value associated with high quality reformatted sagittal and coronal plane images, CT is useful for depiction of spondylolysis, pseudoarthrosis, scoliosis, and for post-surgical evaluation of bone graft integrity, surgical fusion, and instrumentation.

Myelography/CT

"Plain" myelography was the mainstay of lumbar herniated disc diagnosis for decades. It is now usually combined with post-myelography CT. The combined study is complementary to plain CT or MRI and occasionally more accurate in diagnosing disc herniation, but suffers the disadvantage of requiring lumbar puncture and contrast injection. It may also be useful in surgical planning.

Thermography, Discography, CT Discography

Expert panels agreed that these imaging modalities were either too nonspecific (thermography) or carried additional risk (discography) not warranted in view of the efficacy of other less invasive imaging procedures. When other studies fail to localize the cause of pain, discography may occasionally be helpful. Although the images often depict nonspecific aging or degenerative changes, the injection itself may reproduce the patient's pain, which may have diagnostic value.

Abbreviations

• CT, computed tomography
• MRI, magnetic resonance imaging
• NUC, nuclear imaging

Algorithms were not developed from criteria guidelines.

The recommendations are based on analysis of the current literature and expert panel consensus.

• Bradley WG Jr, Seidenwurm DJ, Brunberg JA, Davis PC, DE La Paz RL, Dormont D, Hackney DB, Jordan JE, Karis JP, Mukherji SK, Turski PA, Wippold FJ, Zimmerman RD, McDermott MW, Sloan MA, Expert Panel on Neurologic Imaging. Low back pain. [online publication]. Reston (VA): American College of Radiology (ACR); 2005. 7 p. [23 references]

Not applicable: The guideline was not adapted from another source.

1996 (revised 2005)

American College of Radiology - Medical Specialty Society

The American College of Radiology (ACR) provided the funding and the resources for these ACR Appropriateness Criteria®.

Committee on Appropriateness Criteria, Expert Panel on Neurologic Imaging

Panel Members: William G. Bradley, Jr, MD, PhD; David J. Seidenwurm, MD; James A. Brunberg, MD; Patricia C. Davis, MD; Robert Louis De La Paz, MD; Pr. Didier Dormont; David B. Hackney, MD; John E. Jordan, MD; John P. Karis, MD; Suresh Kumar Mukherji, MD; Patrick A. Turski, MD; Franz J. Wippold II, MD; Robert D. Zimmerman, MD; Michael W. McDermott, MD; Michael A. Sloan, MD, MS

Not stated

This is the current release of the guideline.

This guideline updates a previous version: Anderson RE, Drayer BP, Braffman B, Davis PC, Deck MD, Hasso AN, Johnson BA, Masaryk T, Pomeranz SJ, Seidenwurm D, Tanenbaum L, Masdeu JC. Acute low back pain--radiculopathy. American College of Radiology. ACR Appropriateness Criteria. Radiology 2000 Jun;215(Suppl):479-85.

The appropriateness criteria are reviewed annually and updated by the panels as needed, depending on introduction of new and highly significant scientific evidence.

None available

This summary was completed by ECRI on July 31, 2001. The information was verified by the guideline developer as of August 24, 2001. This summary was updated by ECRI on March 28, 2006. This summary was updated by ECRI Institute on May 17, 2007 following the U.S. Food and Drug Administration (FDA) advisory on Gadolinium-based contrast agents. This summary was updated by ECRI Institute on June 20, 2007 following the U.S. Food and Drug Administration (FDA) advisory on gadolinium-based contrast agents.