Lumbar Herniated Discs: Diagnostic and Treatment Decision-Making
Richard Deyo, MD and Sohail Mirza, MD discuss recent research on lumbar herniated discs and ask, “What testing and treatment would you recommend?”
The authors present a vignette of an adult male presenting with sudden onset of low back and left leg pain. Although the patient reportedly has no significant medical history, the patient is certain he “slipped a disc” and requests an MRI. The question posed is, “What testing and treatment would you recommend?”
Richard Deyo, MD and Sohail Mirza, MD discuss the current research on lumbar herniated discs, including diagnostic pearls along with the most efficacious treatment options and guidelines in a recent issue of The New England Journal of Medicine.
Patients presenting with acute lower back and leg pain without severe neurological deficit usually respond to NSAIDs and physical therapy without necessity of an MRI. However, if symptoms persist beyond a 4-6 week period, or neurological deficits worsen, an MRI is appropriate. An epidural steroid injection may be recommended for diagnostic as well as therapeutic benefit. Depending on the results of the patient’s examination, nonoperative treatment outcomes, and MRI confirmation of herniated disc, surgical intervention may be considered.
Lumbar radiculopathy is considered to be both a biochemical (inflammatory) and mechanical process with both genetic and environmental causes. Herniated discs, although the leading cause of lumbar radiculopathy, are frequently found in asymptomatic patients. According to the authors, “The natural history of herniated lumbar discs is generally favorable, but patients with this condition have a slower recovery than those with nonspecific back pain.” In fact, they added, “MRI shows shrinkage of most herniated discs over time, and up to 76% partially or completely resolve by 1 year.” However, recurrences are common. One study showed a 25% recurrence rate.
Physical Examination and Imaging
A clinical history of leg pain that is worse than back pain, typical dermatomal pattern of symptom distribution, and a positive ipsilateral straight leg raise test are the most sensitive factors for diagnosing a herniated disc. A positive crossed straight leg raise, paresis, and impaired reflexes show the most specificity.
The authors stated, “Early MRI is indicated in patients with progressive or severe deficits (eg, multiple nerve roots) or clinical findings that suggest an underlying tumor or infection (eg, findings that indicate injection-drug use or fever).” Furthermore they indicated, “Otherwise, CT or MRI is necessary only in a patient whose condition has not improved over 4 to 6 weeks with conservative treatment and who may be a candidate for epidural glucocorticoid injections or surgery.” Routine use of CT or MRI is not recommended by the authors and EMG/NCV only with “ambiguous symptoms or findings on examination and CT or MRI.”
Conservative, Nonoperative Treatment
Studies suggest that herniated discs typically improve after 6 weeks, therefore according to the authors, “Conservative therapy is generally recommended for 6 weeks in the absence of a major neurologic deficit.”
There is a lack of clear benefit of drug therapy in sciatica, including NSAIDs, acetaminophen, antiepileptic drugs, antidepressants, oral glucocorticoids, opioids and muscle relaxants. However, NSAIDs and opioids do provide some short-term relief of back pain. However, regarding opioids the authors concluded, “The use of opioids should be limited to patients with severe pain and should be time-limited from the outset.”
Epidural steroid injections have shown improvements in pain levels and function in a systematic review, and procedural complications were reportedly rare. However the FDA, “recently required a warning on product labels for glucocorticoids,” the authors commented.
Physical therapy can provide some short-term relief, but lumbar traction showed no benefit over sham treatment in a meta-analysis of 32 randomized clinical trials (RCTs). The authors discussed two RCTs involving chiropractic manipulation. One compared chiropractic to home exercise, which showed chiropractic edging out exercise at 12 weeks, but not at 1-year. In the other study the authors concluded, “Patients who had acute sciatica with MRI-confirmed disc protrusion showed that at 6 months, significantly more patients who underwent chiropractic manipulation had an absence of pain than did those who underwent sham manipulation (55% vs. 20%).”
Surgery is appropriate for patients with major neurological deficits and “have nerve-root compression that is confirmed on CT or MRI, a corresponding sciatica syndrome, and no response to 6 weeks of conservative therapy” the authors reiterated. Also, the main benefit to surgery is faster relief, as “most, although not all, trials showed no significant advantage of surgery over conservative treatment with respect to relief of sciatica at 1 to 4 years of follow-up.”
With the advent of microdiscectomy and minimally invasive techniques, cases have shifted to ambulatory surgical facilities with quicker recovery times allowing for a faster return to work. The authors also stated, “Procedural complications of lumbar discectomy are less common than procedural complications of other types of spine surgery.”
Disclosure: Richard Deyo, MD reports receiving a financial award from NuVasive as part of a lifetime achievement award from the International Society for the Study of the Lumbar Spine. No other potential conflict of interest relevant to this article was reported.