Evaluation and Management of Low Back Pain: Part 1

Although several guidelines have been published on the diagnosis and treatment of acute LBP (most notably that issued by the US Department of Health and Human Services in 1994¹), there has been a dearth of similar guidelines based on the scientific literature for chronic LBP. Recently, the American College of Physicians and the American Pain Society (ACP/ APS) released the first comprehensive guideline on chronic LBP based on the published evidence, and it is probably the most up-to-date review of acute LBP.²

The ACP/APS guideline is divided into 3 sections: (1) an overview of diagnosis and evaluation, (2) nonpharmacological therapies, and (3) use of medications. In this column, I discuss the information covered in the first section; the other sections will be discussed in my next column.

Evaluating the patient with LBP To help identify possible causes of LBP, the guideline recommends that a focused history and physical examination should be performed in order to place the patient in 1 of 3 broad categories: nonspecific LBP, pain associated with radiculopathy or spinal stenosis, or pain potentially associated with another specific cause. The guideline notes that more than 85% of patients who present to health care providers suffer from nonspecific LBP for which there is no clear underlying cause, while LBP associated with serious illnesses, such as cancer or infection, is relatively uncommon. It provides an algorithm to aid in determining whether an underlying illness should be suspected. For example, further workup would be warranted when a history of cancer or unexplained weight loss suggests that this disease may be present or when there are progressive neurological deficits, such as weakness or fecal or urinary incontinence, indicating the presence of spinal cord compression.

Because of the relative infrequency of these more serious problems as causes of LBP and the ability of physicians to determine whether they are likely to be present from the patientÕs history and physical examination, the guideline advises against the routine use of diagnostic testing, including imaging studies, in patients in whom there is little reason to suspect the presence of these conditions. Unfortunately, most patients with chronic LBP and many with acute LBP who are evaluated by physicians end up undergoing diagnostic testing, most commonly MRI. Although it is widely perceived by patients and many clinicians that this is necessary to formulate a treatment plan, experts on LBP feel that rather than providing information that benefits patients, the results of these tests may be used to support interventions that at best provide little benefit and may actually make things worse.

The problem with these tests is that while structural abnormalities such as bulging intervertebral disks are commonly detected, it is questionable whether there is any correlation between their presence and LBP. This is supported by studies that have demonstrated that many people who have the same abnormalities do not have LBP. The guideline notes that even with a true herniation of a lumbar disk with accompanying radiculopathy, the majority of patients will improve within 4 weeks with noninvasive management. Thus, in these patients, imaging studies offer little benefit in treatment or predicting outcome.