Lumbar (Intervertebral) Disc Disorder Management in the ED

The intervertebral discs act as shock absorbers and are found between the bodies of the vertebrae. They have a central area composed of a colloidal gel, called the nucleus pulposus, which is surrounded by a fibrous capsule, the annulus fibrosis. This structure is held together by the anterior longitudinal ligament, which is anterior to the vertebral bodies, and the posterior longitudinal ligament, which is posterior to the vertebral bodies and anterior to the spinal cord. The muscles of the trunk provide additional support.

The most common site of disc herniation is at the L5-S1 interspace in the lumbosacral region. This is believed to be due to the thinning of the posterior longitudinal ligament as it extends caudally.

Nomenclature specific to lumbar disc disease is as follows:

• Disc bulge - Annular fibers intact
• Disc protrusion - Localized bulging with damage of some annular fibers
• Disc extrusion - Extended bulge with loss of annular fibers, but disk remains intact
• Disc sequestration - Fragment of disk broken off from the nucleus pulposus

The history may be sufficient to make presumptive diagnosis of a disc disorder, or it may guide the physician's usage of ancillary testing and consultations to further differentiate both the specific type of disc disease and potential other etiologies of the patient's back pain.

Patients with disc disease usually are not able to give a precise time that the problem began because it usually is preceded by multiple episodes of less severe low back pain.

Asking the patient the location of the pain is important. Pain that is localized to the lower back and gluteal area is often associated with disc disease. Pain associated with nerve root involvement commonly radiates down the leg, particularly below the level of the knee.

Ask the patient about any unusual recent activity, especially if it involved the patient remaining in a flexed or rotated position. Find out if the patient experienced any recent trauma. Pain with flexion, rotation, or prolonged sitting or standing, as well as sharp (rather than dull) pain, is suggestive of disc disease.

The onset of pain may begin suddenly[5] or gradually after injury. Typically, the pain is located bilaterally at the posterior belt line. The pain pattern usually is referred rather than radicular. Back motion, which includes sitting, standing, lifting, bending, and twisting, usually aggravates the pain; it often is relieved with rest and a recumbent position.

Nerve roots exit the spine below the intervertebral disks; thus, herniation of a disk involves the nerve root below it.

Observe the patient for abnormal gait, which is suggestive of a loss of the normal rhythm. Have ambulatory patients walk on their toes to test the function of S1.

Observe the patient for abnormal posture, which is suggestive of splinting or guarding from pain.

Test the patient's ability to dorsiflex the foot while sitting to test the L5 nerve root. Test for sensory loss that corresponds to a dermatomal area.

Palpation of the lumbar spine and lower back is not helpful in the diagnosis of disc disease, but it should be done to rule out other causes of low back pain.

A positive straight leg raising test is indicative of nerve root involvement. This test is performed while the patient is lying supine with one leg either straight or flexed at the knee, with the sole of the foot flat on the stretcher. The other leg is kept straight and lifted by the examiner. If pain occurs when the leg is lifted between 30-70 degrees from horizontal and travels down the leg until below the knee, the test is positive.

Nerve root stretch test results are often negative.

Patients may exhibit decreased lumbar range of motion (ROM).

The usual motor, sensory, and reflex examinations (including perianal sensation and anal sphincter tone when appropriate) should be performed.

A careful abdominal and vascular examination is mandatory.

Laboratory tests generally are not helpful in the diagnosis of lumbar disc disease.

Indications for screening laboratory examinations include pain of a nonmechanical nature, atypical pain pattern, persistent symptoms, and age greater than than 50 years.

Laboratory may include the following to rule out other disease:

• Complete blood count (CBC) with differential
• Erythrocyte sedimentation rate (ESR)
• Alkaline and acid phosphatase level
• Serum calcium level
• Serum protein electrophoresis

Radiographic studies are very helpful in the diagnosis of lumbar disc disease,[8] but several important caveats should be taken into account with the use of these tests.[9]  The American College of Radiology Appropriateness Criteria does not recommend imaging studies for uncomplicated acute low back pain.[10]  

Most patients with pain from lumbar disc disease have resolution of their symptoms with conservative treatment.

For an otherwise healthy individual, unless the patient is immobilized completely by the pain and requires admission or the pain has been present for more than 6 weeks, diagnostic studies are not recommended. Elderly patients or those with a history of cancer or chronic infection (including tuberculosis), trauma, or osteoporosis should have imaging studies performed as part of their routine workup during initial presentation.

MRI is the imaging modality of choice in evaluating patients with lumbar disk disease.[6, 10] Studies have shown that as many as 60% of people without back symptoms have disk bulges and protrusions on MRI.[11] Therefore, these findings may not correlate with the patient's symptoms.[12]

In a study of 283 patients with sciatica with confirmed disc herniation, MRI assessment of nerve root compression and extrusion of a herniated disc was associated with less leg pain at 1-year follow-up. However, according to the study, MRI findings seemed not to be helpful in determining which patients would do better with early surgery versus prolonged conservative care.[12]

CT scanning is useful for diagnosing disc disease but is less sensitive than MRI. CT scanning of the abdomen can help evaluate and rule out other etiologies of pain, such as aortic aneurysm, ureteral calculi, and intra-abdominal causes. Combining CT scan with myelography can increase the sensitivity of the modality for spinal cord pathology.

Myelography may provide a definitive diagnosis on its own, but this is an invasive test requiring a lumbar puncture and the use of contrast material.

Plain films of the lumbar spine are generally not helpful in the diagnosis of lumbar disc disease, except to rule out other diseases and to evaluate for possible skeletal etiology as the cause of the patient's symptoms. They should be performed in patients who are elderly or in those with a history of cancer or chronic infection (including tuberculosis), trauma, or osteoporosis.

Technetium-99m-labeled phosphorus indicates active mineralization of bone. A bone scan is indicated to rule out tumors, trauma, or infection.

Patients should lie in a position in which they are most comfortable. Muscle relaxants are of limited use, and clinical studies have not proven their efficacy. This class includes benzodiazepines, methocarbamol, and cyclobenzaprine. Patients should be warned that all of these drugs are sedating. Opioids provide very effective acute pain relief, but they should not be used in patients with chronic pain. Salicylates, acetaminophen, and nonsteroidal anti-inflammatory drugs (NSAIDs) all have been used in the treatment of pain from lumbar disc disease, but none of these has been shown to be superior to the others. Acetaminophen lacks anti-inflammatory activity.[13, 14]

Of 76 patients who presented to an emergency department with low back pain, 42 (55%) had resolution or return of pain to baseline with conservative management; 18 (24%) had improvement with intervention (epidural steroid injection or kyphoplasty); 8 (11%) improved with surgery; and 8 (11%) had persistent pain.[15]

Bed rest is not recommended most of the time. The exception is for patients whose pain is so severe that they cannot ambulate. Prolonged immobilization may worsen pain and extend recovery time. Strict bed rest should never exceed 2 days. Patients should be encouraged to begin limited activity as soon as possible.

Whether spinal manipulation (ie, chiropractic care) improves the rate of recovery in patients with disc disease is controversial.

Multiple surgical techniques have been used in patients with disc herniation who have not responded to 6 weeks of conservative therapy. These surgical techniques include discectomy, spinal fusion, and injection of chymopapain.[16, 17, 18, 19]

The Spine Patient Outcomes Research Trial (SPORT) failed to find any statistical superiority of surgical treatment versus conservative treatment for lumbar disc herniation.[20, 21]  This occurred because the study design allowed crossover of treatment based on the patients' preference. These findings suggest that, in most cases, there is no clear reason to advocate for surgery apart. Patient choice appears to be the most important predictive factor.

American College of Radiology

The ACR Appropriateness Criteria includes the following recommendations[10, 22] :

• Uncomplicated acute low back pain and/or radiculopathy are benign, self-limited conditions that do not warrant any imaging studies.
• MRI of the lumbar spine should be considered for patients presenting with red flags that raise suspicion of a serious underlying condition, such as cauda equina syndrome, malignancy, or infection.
• In patients with a history of low-velocity trauma, osteoporosis, or chronic steroid use, initial evaluation by radiography is recommended.
• In the absence of red flags, first-line treatment for chronic low back pain remains conservative therapy with both pharmacologic and nonpharmacologic (eg, exercise, remaining active) therapy.
• If there are persistent or progressive symptoms during or after 6 weeks of conservative management and the patient is a candidate for surgery or intervention or if diagnostic uncertainty remains, MRI of the lumbar spine is the initial imaging modality of choice.
• MRI is the imaging procedure of choice in patients suspected of cord compression or spinal cord injury.
• Patients with recurrent low back pain and a history of surgical intervention should be evaluated with contrast-enhanced MRI.

American College of Physicians

The American College of Physicians (ACP) guidelines on noninvasive treatments for acute, subacute, and chronic low back pain include the following key recommendations[23] :

• For acute or subacute low back pain, nonpharmacologic treatment with superficial heat, massage, acupuncture, or spinal manipulation should be the initial therapy.
• Use NSAIDs or skeletal muscle relaxants if pharmacologic treatment is necessary.
• For chronic low back pain, initial nonpharmacologic treatment includes exercise, multidisciplinary rehabilitation, acupuncture, mindfulness-based stress reduction, tai chi, yoga, motor control exercise, progressive relaxation, electromyography biofeedback, low-level laser therapy, operant therapy, cognitive-behavioral therapy, and spinal manipulation.
• For chronic low back pain with inadequate response to nonpharmacologic therapy, pharmacologic treatment with NSAIDs as first-line therapy or tramadol or duloxetine as second-line therapy may be considered.
• Opioids are an option in patients in whom nonpharmacologic and nonopioid pharmacologic treatments have failed, but only if the potential benefits outweigh the risks for individual patients and after a discussion of known risks and realistic benefits with patients.

National Institute for Health and Care Excellence

The United Kingdom's National Institute for Health and Care Excellence (NICE) guidelines on low back pain recommend nonpharmacologic therapies over pharmacologic pain relief for the initial treatment of back pain. A stratified approach to management based on scores from prognostic screening questionnaires is also recommended in the NICE guidelines.[24]

NSAIDs are recommended by NICE for the treatment of both acute and chronic low back pain. The NICE guidelines recommend offering weak opioids to patients with acute low back pain if NSAIDs are contraindicated or ineffective for acute pain, but prescribing opioids for chronic low back pain is discouraged.[24]

The NICE guidelines recommend radiofrequency denervation for selected patients with persistent low back pain.[24]

American Pain Society

Recommendations from the American Pain Society (APS) include the following[25] :

• Interdisciplinary rehabilitation emphasizing cognitive-behavioral approaches should be considered for patients who do not respond to usual interventions.
• Provocative discography (injecting material into a disc nucleus in an attempt to reproduce the patient's typical pain) is not recommended.
• Facet joint corticosteroid injection, prolotherapy (repeated injections of irritant material to stimulate an inflammatory response), and intradiscal corticosteroid injection are not recommended.
• Persistent disabling symptoms and degenerative spinal changes should prompt discussion and shared decision-making regarding surgery or interdisciplinary rehabilitation (evidence is insufficient to weigh the risks and benefits of vertebral disc replacement in these patients).

The goals of therapy are to reduce pain and inflammation.[26]

Class Summary

These agents are used most commonly for the relief of mild to moderately severe pain. Although effects of NSAIDs in the treatment of pain tend to be patient specific, ibuprofen usually is the DOC for initial therapy. Other options include flurbiprofen, ketoprofen, and naproxen.

Ibuprofen (Ibuprin, Advil, Motrin)

Usually DOC for treatment of mild to moderately severe pain if no contraindications.

Ketoprofen (Oruvail, Orudis, Actron)

Used for relief of mild to moderately severe pain and inflammation. Administer small dosages initially to patients with small body size, to elderly persons, and to those with renal or liver disease. Doses higher than 75 mg do not increase therapeutic effects. Administer high doses with caution, and closely observe patient for response.

Flurbiprofen (Ansaid)

May inhibit enzyme cyclooxygenase, which, in turn, inhibits prostaglandin biosynthesis. These effects may be mechanism of its analgesic, antipyretic, and anti-inflammatory activities.

Naproxen (Anaprox, Naprelan, Naprosyn)

Used for relief of mild to moderately severe pain. Inhibits inflammatory reactions and pain by decreasing activity of enzyme cyclooxygenase, causing decrease in prostaglandin synthesis.