Dr Scott Boden, professor of Orthopedic Surgery at Emory University School of Medicine and director of the Emory Orthopedics & Spine Center, answers four questions from Orthopaedia about back pain, among other things. [Related information can be found in the Orthopaedia chapters on lumbar spondylosis and lumbar disc disease.]

 

Orthopaedia: You were the lead author on the paper, “Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation.” This study showed that abnormal findings on lumbar MRIs are common even in people without symptoms. This paper has been one of the most cited papers in orthopaedic surgery (more than 3,000 times, according to PubMed), so clearly it has been read and respected. Nonetheless, its message–namely, “be slow to obtain an MRI and be certain to clinically correlate it because incidental findings can mislead”– may not have been so universally accepted. What is your recommended strategy for getting a lumbar MRI in a patient with back pain, understanding that patients want the test, insurance ultimately covers it (maybe after some hassle) and that MRIs themselves –though not their downstream treatments, perhaps- are thought to be risk-free?

SCOTT BODEN: That paper you referred to was one of my first papers and one that I did while in residency. Unfortunately, the impact of my next 200 papers never reached that level, so it’s been downhill from there.

It is important to distinguish ordering an MRI in a patient with predominantly low back pain from a patient with radiating leg pain.  In the case of back pain from a patient with radiating leg pain, the most likely cause of radiating leg pain is either a herniated disc or spinal stenosis. In that case, an MRI is not needed until 6 to 12 weeks of non-surgical treatment has been unsuccessful. In fact, the MRI should really be obtained as a confirmatory test for surgical planning, regarding the type and location of a compressive lesion. In addition to all other reasons, a delayed MRI is best because most disc herniations shrink after a few months, and an old MRI could show a disc herniation that is no longer present.

As for the patient with predominantly low back pain without leg pain, an MRI is ideally delayed until six months of non-operative treatment have been unsuccessful. In regards to this case, our study showed that most individuals over the age of 30–even those with no back symptoms– will have age-related findings such as disc degeneration, disc herniation or spinal stenosis found on their MRI. Moreover, since the majority of back and leg pain episodes are self-limited, seeing an MRI with a graphic disc herniation or multiple levels of disc degeneration might prompt more aggressive treatment prematurely and unnecessarily.

The bottom line is that unless there is a history or suspicion of trauma, malignancy, or infection, MRI should be delayed until adequate non-surgical treatment has been attempted, and that the MRI results might potentially change the course of treatment.

Orthopaedia: You were also an author of the paper “Surgical versus nonsurgical therapy for lumbar spinal stenosis” in the New England Journal of Medicine, another instant classic cited more than 1,000 times. This paper reported that patients who underwent surgery showed significantly more improvement vs patients who were treated non-surgically. On the other hand, a critic might say there is a large placebo effect from a major operative intervention, and that short of a placebo-controlled randomized controlled trial, we really can’t be sure of the results. After all, in the placebo-controlled randomized controlled trial of arthroscopy for knee arthritis, the astounding result was not so much that both groups did equally well (though that was interesting!), but that both groups reported subjective improvement. How would you respond to that critique?

SCOTT BODEN: This paper was from the SPORT (Spine Patient Outcomes Research Trial) project that was at the time one of the largest prospective randomized surgery clinical trials in orthopaedics. It was a collaboration of nearly 10 centers, thousands of patients, and many years of work. There were both a randomized arm and an observational arm in the study. As you can imagine, it is very difficult to design and conduct a randomized surgery trial when patients and surgeons have pre-determined biases about what treatments work and which treatment is needed for the case at hand, but this was a carefully planned design that accounted for that as well as can be done.

Unlike the case of lumbar disc herniation, where the majority of patients improve without surgery, patients with severely symptomatic lumbar spinal stenosis rarely improve spontaneously. That is because, unlike disc herniations that can shrink due to enzymatic digestion, the enlargement of the facet joints, thickening of the ligamentum flavum and bulging of the disc–that is, sources of neurologic compression in spinal stenosis–are unlikely to diminish over time. In fact, they are likely to increase.

Hence, the SPORT study confirmed that surgery was effective for spinal stenosis patients that had symptoms that persisted for more than 6 to 12 weeks. In any clinical trial, some of the patients randomized to non-surgical treatment will improve, and others will not. The study clearly showed that outcomes were better in the surgically treated group. Would the results be even more robust with a placebo arm? Perhaps. But unlike the case of a minor procedure like knee arthroscopy, sham surgery for lumbar stenosis is simply not feasible. Evidence based medicine requires use of the best available evidence, and I think the SPORT trial offered that.

Orthopaedia: The paper “US Spending on Personal Health Care and Public Health, 1996-2013” in JAMA examined spending on personal health care and public health in the United States and estimated that the cost of caring for back pain exceeds the spending on care for asthma, breast cancer, cirrhosis, heart failure and leukemia – combined. Do you have any suggestions for controlling that? Or does it simply reflect the burden of disease?

SCOTT BODEN: The cost of caring for back pain varies dramatically from country to country. This cost variation depends on the country’s healthcare insurance, workers compensation system and social norms and expectations. Thus, it is difficult to compare the burden of disease between countries when there is that much variability. Given the United States’ healthcare insurance, workers compensation system and social norms and expectations, back pain is associated with a very high burden of disease.

That being said, an argument can be made that we spend too much. One reason may be patients’ expectations. As is the case for any arthritic condition, a “cure” for back pain may be unrealistic or unattainable, but that won’t stop some people from trying. In addition, for some patients, the natural aging process of the spine may be painful while in others it is not–and treating those with imaging evidence of disease but minimal symptoms is another way to run up the bill. The key is not to intervene overly aggressively in an aging process unless there is an identifiable and discrete source of pain, and that there is a reliable treatment option for that condition. In addition, given the episodic nature of low back pain, many currently used treatments lack the hard evidence of efficacy from rigorous randomized trials, which perpetuates expenditures in situations where people feel the need to try “something” that might possibly help alleviate pain.

Orthopaedia: Let’s end with an easy one: In context of the opioid epidemic, what is the proper role for narcotic pain medications for patients with back pain?

SCOTT BODEN: I was taught by my mentors that there is really no role for narcotics in acute low back pain. With that said, there are certainly situations where individuals have real pathology that is not amenable to surgery or the individual is not a surgical candidate, in which case low dose narcotics (without escalation) may be an option. This option should be offered only by a pain management physician, with a pain contract, and proper monitoring.