Lumbar Disc Disease

By admin On Oct 5, 2023

Ovid: 5-Minute Sports Medicine Consult, The

Lumbar Disc Disease

Matthew D. Shores

Basics

Description

In regard to terminology, lumbar disc disease may represent a broad spectrum of pathology, including disc herniations, disc space narrowing, disc desiccation, and sclerosis of the end plates, as well as many lumbar spine abnormalities with various etiologies:
- Most commonly, the term refers to lumbar disc herniation, and this topic most specifically addresses lumbar disc herniation.
Lumbar disc herniations are the most common cause of sciatica, although not the only cause.

Epidemiology

Incidence

Approximate lifetime incidence is 5% in males and 2.5% in females.
Peak incidence is between the 4th and 6th decades of life (30s to 50s).

Risk Factors

Lifestyle risks include sedentary occupations, physical inactivity, and smoking.
Increased tendency in families with acquired spinal disorders, such as ankylosing spondylitis and degenerative arthritis.
In addition, more common in patients with increased height and weight.

Etiology

Compromise in the integrity of the annulus fibrosus may allow herniation of the nucleus pulposus.
Herniation of the nucleus pulposus of the disc may compress and irritate the adjacent nerve root.
Most common site of herniation is L5–S1, affecting the S1 nerve root. 2nd most common site of herniation is L4–L5, affecting the L5 nerve root.

Diagnosis

History

Often presents with history of multiple episodes of back pain that vary in severity and duration:
- This accumulated recurrent back pain can lead to disc herniation.
- May present following an acute lifting or twisting injury
- Often worsened by coughing, sneezing, and Valsalva
Presents with sciatic pain, that is, pain originating in the low back and radiating from the buttock down the posterior or lateral thigh to the ankle or foot:
- Patients may have a difficult time finding a position of comfort.
Sciatica has a high sensitivity for lumbar disc herniation but low specificity:
- More specific for disc herniation if pain is greater in the leg than in the back or pain that is worse with the Valsalva maneuver.
Can present with back pain that does not radiate, but patient may note motor or sensory deficits.
Red flag symptoms that may indicate an alternative diagnosis, including cauda equina syndrome, infection, or neoplasm:
- Fecal incontinence
- Loss of motor function
- Perianal numbness
- Radicular symptoms lasting >6 wks
- Saddle anesthesia
- Urinary retention
- Unexplained fever
- Weight loss

Physical Exam

A full physical exam of the back, pelvis, and lower extremities should be done, including a detailed neurological exam.
Provocative tests should include a straight leg raise test, the most sensitive test for lumbar disc herniation (1):
- Straight leg raise can be done seated or supine, although for lumbar disc herniation, supine test has higher sensitivity (1).
- Crossed straight leg raise is highly specific for lumbar nerve root entrapment, including that caused by lumbar disk herniation.
Other findings may include:
- Sensory loss:
  - Medial foot, including plantar aspect of 1st toe sensory loss (L4 involvement)
  - Dorsum of the foot sensory loss (L5 involvement)
  - Lateral heel sensory loss (S1 involvement)
- Tendon reflex changes:
  - Diminished or lost patellar tendon reflex (L4 involvement)
  - Please note: There is no L5 tendon reflex
  - Diminished or lost Achilles reflex (S1 involvement)
- Motor finding (often late findings):
  - Weak tibialis anterior and quadriceps (L4 involvement)
  - Weak foot inversion, eversion, dorsiflexion, and 1st toe extension (L5 involvement)
  - Weak hamstrings or gastrocnemius (S1 involvement)
Please note Waddell's signs to assess malingering:
- Tenderness:
  - Superficial tenderness with light palpation or tenderness on deep palpation but nonanatomic over a large area
- Simulated tests:
  - Axial loading causes low back pain, or rotation of the hips and shoulders together causes low back pain
- Distraction:
  - Formal straight leg raise is positive, but when distracted, straight leg raise does not produce pain.
- Regional sensory or motor changes:
  - Glove and stocking sensation loss or nonanatomic muscular weakness (various muscles innervated by different nerve roots)
- Overreaction:
  - Exaggerated response or emotions

Diagnostic Tests & Interpretation

Imaging

MRI is the preferred imaging modality; however, in the absence of red flag symptoms, MRI should be delayed for a 6-wk trial of conservative treatment. If symptoms persist beyond 6 wks, MRI may then be considered (1)[A]:
- Please note, it has been demonstrated that in asymptomatic patients under the age of 60 with no history of back complaints, ∼50% of patients had bulging discs and nearly 25% had herniated discs on MRI (2,3).
Emergent imaging may be considered for red flag symptoms such as urinary retention, fecal incontinence, saddle anesthesia, progressive neurologic changes, and intractable pain.
Plain radiographs may be beneficial to rule out bony abnormalities (such as metastic disease or fractures); in addition, they may demonstrate age-related degenerative changes.

Differential Diagnosis

Cauda equina syndrome
Hip arthritis
Knee arthritis
Meralgia paresthetica
Piriformis syndrome
Sacroiliitis
Spinal neoplasms
Spinal stenosis
Trochanteric bursitis
Vascular insufficiency
Vertebral fracture or infection

P.367

Treatment

Medication

First Line

NSAIDs, acetaminophen, and muscle relaxants may be effective for nonspecific low back pain, but studies for lumbar disc herniation are limited (1)[B].
In the treatment of pain associated with lumbar disc herniation, systemic steroids are no better than placebo (1)[A].
Opioid medications and opioid agonists, such as tramadol, are often included as a standard component in the conservative treatment of patients with severe pain, although their use has not been extensively studied.

Second Line

In lumbar disc herniation, epidural steroid injections can improve pain in the short term, but do not provide long-term relief (1,4)[A].

Complementary and Alternative Medicine

Physical therapy is often incorporated as a component of conservative therapy:

However, evidence shows little to support physical therapy in improving pain or functional status.
Modalities such as US and transcutaneous electrical nerve stimulation (TENs) do not have enough quality evidence to clearly assess their effectiveness, although they may provide some short-term benefit.
Traction produces conflicting evidence, but systemic reviews indicate that traction is not effective.
Aerobic conditioning and trunk muscle strengthening are important for good outcomes.

Surgery/Other Procedures

Immediate indications for surgery include:
- Cauda equina syndrome
- Acute myelopathy
- Severe motor deficits
- Intractable pain
In addition, surgery may be considered with the failure of conservative therapy to provide relief within 6–12 wks (1)[A].
Surgical techniques include:
- Open discectomy
- Microdiscectomy
In comparison to conservative management, surgical discectomy has been shown to provide quicker and better relief of pain associated with lumbar disc herniation in the 1st 2 yrs:
- This benefit has been documented up to 2 yrs, after which there is no difference between surgery and conservative management (no long-term benefits with surgery) (1,5,6)[A].

References

1. Gregory DS, Seto CK, Wortley GC, et al. Acute lumbar disk pain: navigating evaluation and treatment choices. Am Fam Physician. 2008;78:835–842.

2. Boden SD, Davis DO, Dina TS, et al. Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation. J Bone Joint Surg Am. 1990;72:403–408.

3. Jensen MC, Brant-Zawadzki MN, Obuchowski N, et al. Magnetic resonance imaging of the lumbar spine in people without back pain. N Engl J Med. 1994;331:69–73.

4. Armon C, Argoff CE, Samuels J, et al. Assessment: use of epidural steroid injections to treat radicular lumbosacral pain: report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology. 2007;68:723–729.

5. Weinstein JN, Lurie JD, Tosteson TD, et al. Surgical vs nonoperative treatment for lumbar disk herniation: the Spine Patient Outcomes Research Trial (SPORT) observational cohort. JAMA. 2006;296:2451–2459.

6. Peul WC, van Houwelingen HC, van den Hout WB, et al. Surgery versus prolonged conservative treatment for sciatica. N Engl J Med. 2007;356:2245–2256.

Additional Reading

Greer S, Chambliss L, Mackler L, et al. Clinical inquiries. What physical exam techniques are useful to detect malingering? J Fam Pract. 2005;54:719–722.

Jarvik JG, Deyo RA. Diagnostic evaluation of low back pain with emphasis on imaging. Ann Intern Med. 2002;137:586–597.

Kerr RS, Cadoux-Hudson TA, Adams CB. The value of accurate clinical assessment in the surgical management of the lumbar disc protrusion. J Neurol Neurosurg Psychiatry. 1988;51:169–173.

Codes

ICD9

722.10 Displacement of lumbar intervertebral disc without myelopathy
722.52 Degeneration of lumbar or lumbosacral intervertebral disc
722.73 Intervertebral disc disorder with myelopathy, lumbar region

Clinical Pearls

Although the specificity is low, straight leg raise in the supine position is the most sensitive physical exam test for lumbar disc herniation.
In the absence of red flag symptoms, conservative management may be attempted for 6 wks prior to obtaining diagnostic imaging such as MRI.
Conservative management may include NSAIDs, muscle relaxants, and opoid analgesics for severe pain:
- Oral steroids have not been shown to be beneficial compared to placebo.
- Epidural steroids may provide short-term relief, but have not been shown to provide long-term relief.
Although in the 1st 2 yrs, surgery offers better improvement in pain in comparison to conservative management, there is no difference in outcome beyond 2 yrs.