SCIATICA

sciatica

Overview of Sciatica

Sciatica is a neuropathic pain syndrome resulting from compression or irritation of the sciatic nerve. It manifests as radicular pain along the L4 to S3 dermatomes, often unilateral, with varying severity. Understanding the etiology and therapeutic approaches is critical for effective management.

Etiology and Pathophysiology of Sciatica

Several pathophysiological mechanisms contribute to sciatic nerve compression:

  • Lumbar Disc Herniation – Herniated nucleus pulposus impinges on the nerve roots, predominantly at L4-L5 or L5-S1 levels.
  • Lumbar Spinal Stenosis – Degenerative narrowing of the spinal canal leads to foraminal impingement.
  • Piriformis Syndrome – Hypertrophy or spasm of the piriformis muscle compresses the sciatic nerve.
  • Sacroiliac Joint Pain – Pain may start at the buttock and refer to the back of the thigh and leg.
  • Facet Joint Pain – Pain may start at the buttock and refer to the back of the thigh and leg, like sacroiliac joint pain.
  • Spondylolisthesis – Anterior displacement of a vertebral body may lead to nerve root compression.
  • Trauma and Neoplasms – Direct injury or space-occupying lesions can exert pressure on the sciatic nerve.
  • Pregnancy-Related Sciatica – Hormonal and biomechanical changes contribute to transient nerve irritation.

Clinical Presentation of Sciatica

The hallmark symptoms of sciatica include:

  • Neuropathic Pain – Sharp, shooting pain radiating from the lumbar spine to the lower extremity.
  • Paresthesia and Dysesthesia – Numbness, tingling, or burning sensations along the sciatic nerve distribution.
  • Motor Weakness – Muscle weakness in knee extension, dorsiflexion, or plantar flexion, depending on the affected nerve root.
  • Reflex Changes – Diminished patellar (L4) or Achilles (S1) reflexes in advanced cases.
  • Provocative Maneuvers – Positive straight leg raise (Lasegue’s test) and crossed straight leg raise tests confirm radiculopathy.

Diagnostic Approach

A thorough clinical evaluation, supplemented by imaging and electrodiagnostic tests, is crucial:

  • MRI Lumbar Spine – Gold standard for detecting disc pathology and nerve root impingement.
  • CT Myelography – Alternative imaging for patients with contraindications to MRI.
  • Electromyography (EMG) and Nerve Conduction Studies – Assess nerve dysfunction and rule out peripheral neuropathies.
  • Laboratory Tests – ESR, CRP, and rheumatologic markers may be necessary to exclude inflammatory or infectious causes.

Evidence-Based Treatment Strategies

Conservative Management

  • Pharmacologic Therapy – NSAIDs, corticosteroids, and neuropathic agents (gabapentin, pregabalin) for symptomatic relief.
  • Physical Therapy – Strengthening, stretching, and McKenzie exercises aid in symptom resolution.
  • Manual Therapy – Chiropractic and osteopathic manipulations can provide short-term relief.
  • Lifestyle Modifications – Weight reduction, ergonomic adjustments, and activity modifications are crucial.
  • Interventional Pain Management – Epidural steroid injections can offer significant pain relief in refractory cases.

Interventional Pain Management

  • Transforaminal Epidural by sub-pedicular approach – This was the standard treatment in the absence of any neuro deficits and other red flags.
  • TFESI by Kambin’s triangle approach– This is now the preferred technique in absence of neuro deficits.
  • Caudal epidural– Preferred when multiple levels are involved in the lower lumbar area.
  • Interlaminar epidural– When multiple roots are involved in the upper lumbar area.
  • Sacroiliac joint interventions– When sciatica is because of SI joint pain
  • Piriformis intervention– When sciatica occurs because of Piriformis syndrome
  • Facet joint intervention– When sciatica occurs because of facet joint pain, intra-articular steroid injection or RFA of medial branches is done.

Surgical Interventions

Indications for surgical management include refractory pain, progressive neurologic deficits, or cauda equina syndrome. Common procedures include:

  • Microdiscectomy – Earlier, this was the preferred for lumbar disc herniation with radiculopathy.
  • Endoscopic discectomy – Gradually becoming the standard treatment for lumbar disc herniation with radiculopathy.
  • Laminectomy – Indicated for spinal stenosis with neurogenic claudication.
  • Spinal Fusion – Reserved for spondylolisthesis or recurrent disc herniations.

Preventive Measures and Prognosis

Preventing recurrence involves addressing modifiable risk factors:

  • Core Strengthening and Postural Training – Reduces biomechanical stress on the lumbar spine.
  • Ergonomic Optimization – Proper workstation setup minimizes occupational strain.
  • Regular Physical Activity – Low-impact exercises, such as swimming and yoga, promote spinal health.

With appropriate management, most patients experience significant improvement within 6–8 weeks. However, chronic cases may require multimodal treatment approaches.

For advanced pain management techniques and patient referrals, visit Daradia Pain Clinic, a center of excellence in interventional pain medicine.

References:

  1. Ropper AH, Samuels MA. Adams and Victor’s Principles of Neurology. 10th ed. McGraw-Hill Education.
  2. Filler AG. Sciatica and Chronic Pain: Mechanisms and Management. J Neurol Sci. 2017.
  3. National Institute of Neurological Disorders and Stroke (NINDS). Sciatica Overview. NINDS.nih.gov