What are the diagnostic criteria and initial treatment options for sciatica in a primary care General Practice (GP) setting?

Diagnosis and Treatment of Sciatica in Primary Care

How to Diagnose Sciatica

Sciatica is diagnosed clinically through a focused history and physical examination—imaging is not required initially unless red flags are present. 1

Clinical Definition

• Sciatica is pain radiating down the leg below the knee in the sciatic nerve distribution, suggesting nerve root compromise from mechanical pressure or inflammation 2, 3
• This is a symptom, not a specific diagnosis—most cases (>90%) result from lumbar disc herniation at L4/L5 or L5/S1 levels 3

Key History Elements to Obtain

• Location and radiation of pain: Must extend below the knee into the foot/toes to qualify as true sciatica 4
• Pain character: Often neuropathic with burning, electric sensation, or dysesthesia 3
• Aggravating factors: Worsening with spinal flexion/extension, walking, or running 3
• Duration and previous episodes: Important for determining acute (<4 weeks) vs. chronic management 5
• Red flag symptoms requiring urgent evaluation: 1, 3
  • Urinary retention (90% sensitivity for cauda equina syndrome)
  • Fecal incontinence or bladder dysfunction
  • Progressive motor deficits at multiple levels
  • History of cancer, unexplained weight loss, fever, or age >50 with new-onset pain

Physical Examination Components

Perform a focused neurological examination targeting specific nerve root levels: 2

• L4 nerve root: Test knee extension strength and patellar reflex 2
• L5 nerve root: Assess great toe and foot dorsiflexion strength 2
• S1 nerve root: Evaluate foot plantarflexion strength and ankle reflex 2
• Sensory testing: Check for dermatomal deficits in L4, L5, or S1 distributions 3

Straight Leg Raise (SLR) Test: 2

• Standard SLR has 91% sensitivity but only 26% specificity for disc herniation
• A negative SLR does NOT rule out sciatica—the diagnosis relies on the clinical pattern of radicular pain, dermatomal sensory changes, and motor weakness in nerve root distribution 2
• Crossed SLR (pain when raising unaffected leg) is more specific (88%) but less sensitive (29%) 2, 3

When to Order Imaging

• Do NOT order routine imaging for acute sciatica without red flags—it doesn't improve outcomes and may lead to unnecessary interventions 5
• Immediate MRI indicated for: 2
  • Severe or progressive neurological deficits
  • Suspected cauda equina syndrome
  • Red flag symptoms (infection, malignancy)
• Delayed imaging (after 4-6 weeks): For persistent sciatica without improvement despite conservative management, and only if patient is a surgical or epidural injection candidate 2, 5

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Initial Treatment in Primary Care

Advise patients to remain active rather than resting in bed, and initiate first-line pharmacologic therapy with acetaminophen or NSAIDs. 5

First-Line Management (Start Immediately)

Non-Pharmacologic:

• Remain active: Bed rest is contraindicated—staying active is more effective than bed rest 5
• If severe symptoms require brief bed rest, encourage return to normal activities as soon as possible 5
• Apply superficial heat for short-term relief of acute pain 5
• Provide evidence-based education materials (such as The Back Book) as supplement to care 5

Pharmacologic Options:

• Acetaminophen: Weaker analgesic than NSAIDs but more favorable safety profile and low cost 5
  • Monitor for asymptomatic aminotransferase elevations at 4 g/day dosing 5
• NSAIDs: More effective for pain relief than acetaminophen 5
  • Assess cardiovascular and gastrointestinal risk factors before prescribing 5
  • Use lowest effective dose for shortest duration 5
• Skeletal muscle relaxants (cyclobenzaprine, tizanidine, metaxalone): For short-term relief when muscle spasm contributes to pain 5
• Gabapentin: Provides small, short-term benefits for radiculopathy 5
• Tricyclic antidepressants: For pain relief in patients with neuropathic pain components without contraindications 5

Avoid:

• Systemic corticosteroids are NOT recommended—they have not been shown more effective than placebo 5

Second-Line Management (If Symptoms Persist Beyond 2-4 Weeks)

For Acute Sciatica (<4 weeks):

• Spinal manipulation by appropriately trained providers shows small to moderate short-term benefits 5

For Chronic/Subacute Sciatica (>4 weeks):

• Exercise therapy with individual tailoring, supervision, stretching, and strengthening 5
• Acupuncture as adjunct to conventional therapy 5
• Massage therapy shows similar efficacy to other effective interventions 5
• Cognitive-behavioral therapy provides moderate effects 5
• Intensive interdisciplinary rehabilitation for chronic pain (combination of physical, vocational, and behavioral components) 5

Third-Line/Interventional Options (Specialist Referral)

• Epidural steroid injections: Consider for persistent radicular symptoms despite conservative therapy 5
• Surgical consultation: For progressive neurological deficits or failure of 6-8 weeks conservative treatment 5, 4
• Immediate surgical referral: For cauda equina syndrome (medical emergency) 5

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Critical Pitfalls to Avoid

• Do not prescribe prolonged bed rest—it leads to deconditioning and worsens outcomes 5
• Do not order routine imaging initially—most sciatica improves within 2-4 weeks without treatment 4
• Do not rely solely on SLR test—sensitivity decreases with age and negative test doesn't exclude sciatica 2
• Do not use systemic corticosteroids—they are ineffective 5
• Do not miss cauda equina syndrome—urinary retention is the key finding requiring emergency evaluation 3
• Reserve extended medication courses only for patients showing continued benefits without major adverse events 5

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Expected Clinical Course

• Most acute sciatica improves within 2-4 weeks with or without treatment 4, 6
• Psychosocial factors and emotional distress are stronger predictors of outcomes than physical examination findings or pain severity 3
• Conservative treatment for 6-8 weeks is the consensus approach before considering interventional options 6