What is the best course of treatment for a patient with impingement of the exiting L5 (lumbar 5) nerve roots, with left side symptoms worse than the right?

Management of L5 Nerve Root Impingement

For patients with L5 nerve root impingement, a stepwise treatment approach starting with conservative management for 6 weeks followed by imaging and potential interventional treatments is recommended, with surgery reserved for those with persistent symptoms despite conservative care.

Initial Assessment and Management

Clinical Presentation of L5 Nerve Root Impingement

• Symptoms typically include:
  • Pain radiating down the posterior/lateral thigh to the lateral calf and dorsum of foot
  • Numbness/tingling in the L5 dermatome (lateral leg, dorsum of foot, first web space)
  • Weakness in foot/great toe dorsiflexion (extensor hallucis longus)
  • Positive straight-leg raise test (sensitivity 91%, specificity 26%) 1

First-Line Treatment (0-6 weeks)

1. Conservative management is the initial approach for all patients without red flags:

   • Activity modification (remain active, avoid bed rest)
   • Physical therapy focusing on core strengthening and proper body mechanics
   • Pharmacologic therapy:
     • NSAIDs for pain and inflammation
     • Short-term muscle relaxants if muscle spasm present
     • Limited opioids only if severe pain unresponsive to other measures
   • Patient education on favorable natural history and self-care options 1

2. Avoid routine imaging during this initial period:

   • Imaging in the first 6 weeks does not improve outcomes and increases healthcare utilization
   • Plain radiography exposes patients to unnecessary radiation 1

Management After 6 Weeks of Persistent Symptoms

If symptoms persist after 6 weeks of conservative management:

1. Obtain MRI (preferred) or CT if the patient is:

   • A potential candidate for surgery or epidural steroid injection
   • Showing signs of progressive neurological deficit 1

2. Interventional options to consider:

   • Epidural steroid injections for radicular symptoms
   • Selective L5 nerve root blocks (ultrasound-guided approaches may be beneficial) 2
   • These interventions can provide temporary relief while continuing conservative care

Surgical Considerations

Surgery should be considered for patients with:

• Persistent radicular symptoms despite 6+ weeks of conservative management and interventional treatments
• Progressive neurological deficits
• Cauda equina syndrome (medical emergency requiring immediate surgical decompression) 1

Surgical Approaches

The surgical approach depends on the specific pathology:

• Anterior approach: Appropriate for disc space or vertebral body infection 1
• Posterior approach: Most common for L5 nerve root decompression due to disc herniation or stenosis 1
• Direct decompression of the nerve root without hardware revision may be sufficient in some cases 3

Special Considerations

• Asymmetric symptoms (left worse than right): Treatment approach remains the same, but focused on the more symptomatic side for interventional procedures
• Weakness: While concerning, weakness alone is not necessarily an indication for immediate surgery. Pain relief should be the primary surgical indication 4
• Monitoring: Regular reassessment of neurological status is essential to detect progression

Pitfalls and Caveats

• Beware of uncommon causes of L5 radiculopathy that may mimic typical disc herniation:
  • Tarlov cysts
  • Nerve root anomalies
  • Anterolateral malpositioning of S1 pedicle screws 5, 6
• MRI findings (such as bulging discs) are often nonspecific and may be present in asymptomatic individuals 1
• Avoid prolonged use of splinting or bracing as this may lead to muscle deconditioning 1

By following this evidence-based approach, most patients with L5 nerve root impingement will experience significant improvement in symptoms and function.