Sciatica (Adult)

1. Clinical Overview

Summary

Sciatica is a syndrome characterized by radiating pain along the distribution of the sciatic nerve (L4-S3 dermatomes), typically extending from the lower back into the posterior thigh and leg, usually below the knee. It results from compression, inflammation, or irritation of one or more lumbar or sacral nerve roots, most commonly due to lumbar intervertebral disc herniation (90% of cases). [1,2] The condition affects 13-40% of individuals during their lifetime, with peak incidence in the 4th-5th decades. [3] Most cases (approximately 75-90%) resolve with conservative management within 6-12 weeks, though a subset of patients experience persistent symptoms requiring more aggressive intervention. [4,5]

Key Facts

Clinical Pearls

Clinical Pearl: Disc-Root Relationship

• L4/5 disc herniation typically compresses the L5 nerve root (traversing root)
• L5/S1 disc herniation typically compresses the S1 nerve root
• The disc level is named for the vertebrae above and below (e.g., L4/5 is between L4 and L5 vertebrae)
• The exiting root leaves above the pedicle of the same-numbered vertebra (e.g., L4 root exits at L4/5 foramen)

Clinical Pearl: Examination Specificity

• Crossed SLR (raising contralateral leg produces pain in affected leg) is highly specific (90%) but less sensitive (25%) for disc herniation [6]
• Positive SLR is sensitive (80-90%) but less specific (40-60%) [6]
• Radicular pain below the knee is more specific for nerve root compression than back or buttock pain alone
• Leg pain severity typically exceeds back pain in true radiculopathy

Clinical Pearl: Red Flag Recognition

• Urinary retention (not just hesitancy) with painless bladder distension suggests CES
• Saddle anaesthesia (perineal/perianal numbness) is a cardinal CES feature
• Progressive motor deficit (worsening over hours/days) requires urgent imaging
• Bilateral symptoms raise suspicion for central disc prolapse/CES

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2. Epidemiology

Prevalence and Incidence

Risk Factors

Socioeconomic Impact

• Work absence: Mean 2-6 weeks off work for moderate-severe cases
• Healthcare costs: Significant contributor to musculoskeletal healthcare expenditure
• Disability: 5-10% develop chronic symptoms with functional impairment
• Quality of life: Substantial impact during acute phase (SF-36 scores reduced by 30-50%)

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3. Aetiology and Pathophysiology

Causes of Sciatica

Disc Herniation Classification

Exam Detail: Anatomical Classification:

• Protrusion: Nucleus pulposus bulges through annular tear but base > apex diameter
• Extrusion: Disc material extends beyond annular boundaries; base < apex diameter
• Sequestration: Free fragment completely separated from parent disc

Location:

• Central: Midline; may compress cauda equina (CES risk)
• Paracentral/Posterolateral: Most common (90%); compresses traversing root
• Foraminal: Compresses exiting root at neural foramen
• Extraforaminal/Far lateral: less than 10%; may miss on routine imaging

Pathophysiological Mechanisms

DISC DEGENERATION
       ↓
Annular Fissures/Tears
       ↓
Nucleus Pulposus Herniation
       ↓
┌──────────────────┴──────────────────┐
│                                     │
MECHANICAL COMPRESSION          CHEMICAL INFLAMMATION
       ↓                              ↓
Nerve root ischaemia          Pro-inflammatory mediators
Axonal damage                 (phospholipase A2, TNF-α, IL-6)
       ↓                              ↓
       └──────────────┬───────────────┘
                      ↓
            RADICULAR PAIN (Sciatica)
             + Neurological Deficit

Exam Detail: Molecular Pathophysiology:

1. Mechanical Compression

   • Direct pressure on nerve root reduces blood flow (ischaemia)
   • Threshold: > 10 mmHg pressure impairs venous return

   • 30 mmHg impairs arterial flow → axonal dysfunction

   • Demyelination occurs with sustained compression

2. Chemical Inflammation

   • Nucleus pulposus material is immunogenic (sequestered antigen)
   • Release of matrix metalloproteinases (MMPs)
   • Phospholipase A2 levels correlate with pain severity [8]
   • TNF-α, IL-1β, IL-6 sensitize nociceptors
   • Neurogenic inflammation with substance P release

3. Neurophysiological Changes

   • Ectopic discharge from compressed dorsal root ganglion
   • Peripheral and central sensitization
   • Altered ion channel expression (sodium channels)
   • Wallerian degeneration in severe/prolonged compression

Nerve Root Levels and Clinical Syndromes

Exam Detail: Clinical Correlation:

• L5 radiculopathy is the most common (50-60% of cases)
• S1 radiculopathy accounts for 30-40%
• L4 radiculopathy is less common (5-10%)
• Multiple root involvement suggests central disc prolapse or spinal stenosis

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4. Clinical Presentation

History

Red Flag Symptoms

Other Warning Features

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5. Clinical Examination

Neurological Examination by Root Level

Exam Detail: Systematic Motor Testing:

Sensory Testing:

• L4: Medial malleolus, medial shin
• L5: First web space (between great and 2nd toe), dorsum of foot
• S1: Lateral foot, sole, posterior calf

Reflex Testing:

• Knee jerk (L3/4): Patellar tendon - tests femoral nerve/L4 root
• Ankle jerk (S1): Achilles tendon - most sensitive reflex for S1 radiculopathy
• Note: No reliable reflex for L5

Special Provocative Tests

Clinical Pearl: SLR Test Refinements:

• Pain in back/buttock only during SLR is non-specific (likely facet/SI joint)
• True radicular pain must extend below the knee in dermatomal distribution
• Pain at > 70° is usually non-organic or musculoskeletal
• Crossed SLR positive strongly suggests disc herniation (high specificity)

Cauda Equina Examination

Exam Detail: Essential Components:

1. Perianal Sensation

   • Test with light touch/pinprick in saddle distribution (S2-S5)
   • Compare bilaterally
   • Document precisely (not just "reduced")

2. Anal Tone

   • Digital rectal examination
   • Assess resting tone and voluntary squeeze
   • Reduced tone highly suspicious for CES

3. Bladder Function

   • Post-void residual volume (catheterization or bladder scan)

   • 200 mL suggests retention

   • Painless retention is characteristic of CES (versus obstructive retention which is painful)

4. Lower Limb Bilateral Assessment

   • Motor power in all root distributions bilaterally
   • Reflexes bilaterally
   • Sensory testing to level

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6. Investigations

Imaging Indications

Exam Detail: When to Image (Evidence-Based Guidelines):

Immediate Imaging Required:

• Red flag symptoms/signs (CES, infection, fracture, malignancy)
• Progressive or severe motor deficit (foot drop, quadriceps weakness)
• Sphincter disturbance

Imaging Can Be Deferred (Conservative Trial First):

• Uncomplicated radiculopathy without red flags
• less than 6 weeks duration
• No significant motor deficit
• Patient willing to trial conservative management

Imaging Recommended If:

• Persistent symptoms > 6 weeks despite conservative care
• Worsening despite treatment
• Considering epidural injection or surgery
• Diagnostic uncertainty

Imaging Modalities

MRI Findings in Disc Herniation

Exam Detail: Classification of Disc Pathology on MRI:

1. Normal: Nucleus pulposus contained within annulus fibrosis
2. Disc Bulge: Diffuse circumferential extension of disc margin beyond endplates (> 25% circumference); usually age-related degenerative change
3. Disc Protrusion: Focal/asymmetric extension; base > apex (neck narrower than body)
4. Disc Extrusion: Base < apex; disc material extends through annular defect
5. Sequestration: Free fragment separated from parent disc (high spontaneous resorption rate)

Nerve Root Compression Signs:

• Obliteration of epidural fat
• Nerve root displacement/flattening
• Nerve root enhancement (inflammation)

Caution: 20-30% of asymptomatic adults have disc protrusions on MRI [11]. Correlation with clinical syndrome is essential.

Electrodiagnostic Studies

Indications:

• Diagnostic uncertainty (peripheral neuropathy vs. radiculopathy)
• Multiple level involvement
• Medico-legal documentation
• Planned surgery (confirm level/severity)

Findings in Radiculopathy:

• Needle EMG: Denervation potentials (fibrillations, positive sharp waves) in myotomal distribution; abnormalities appear 2-3 weeks after onset
• Nerve conduction studies: Usually normal (radiculopathy is proximal to dorsal root ganglion); helps exclude peripheral neuropathy
• H-reflex: May be absent/prolonged in S1 radiculopathy

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7. Differential Diagnosis

Exam Detail: Viva Question: How do you differentiate neurogenic claudication (spinal stenosis) from vascular claudication?

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8. Management

Management Algorithm

ACUTE SCIATICA (onset less than 6 weeks)
          ↓
    RED FLAGS?
    ↙         ↘
  YES          NO
   ↓            ↓
URGENT MRI   CONSERVATIVE MANAGEMENT
   ↓         (First-line: 6-12 weeks)
Appropriate      ↓
intervention  ┌────┴────┐
(CES=surgery)│         │
           IMPROVE   PERSISTENT/WORSENING
              ↓           ↓
           CONTINUE    RE-EVALUATE
              ↓           ↓
           GRADUAL     IMAGING (MRI)
           RETURN         ↓
              ↓      Consider:
           PHYSIO   - Specialist referral
           +        - Epidural injection
           PREVENTION - Surgery (if > 6 weeks,
                        failed conservative,
                        significant deficit)

Conservative Management (First-Line)

Exam Detail: Evidence-Based Conservative Approach:

Studies demonstrate that 75-90% of patients with acute sciatica improve within 6-12 weeks with conservative management alone. [4,5] Early surgery provides faster pain relief but no difference in long-term outcomes (1-2 years) compared to conservative care for most patients. [12]

Exam Detail: NICE Guidelines Summary (NG59 - Low Back Pain and Sciatica, 2016):

Do:

• Encourage self-management and continuation of normal activities
• Offer NSAIDs (short course, lowest effective dose)
• Consider neuropathic agents (gabapentin, pregabalin, amitriptyline)
• Offer structured exercise program (group or individual)
• Provide information on natural history (favorable prognosis)

Do NOT:

• Routinely offer opioids
• Offer paracetamol alone for sciatica
• Offer acupuncture
• Offer belts/corsets/traction
• Offer routine spinal injections for acute sciatica (first 6 weeks)

Second-Line: Epidural Steroid Injections

Exam Detail: Evidence Summary:

Epidural corticosteroid injections provide modest short-term pain relief (6 weeks) but no long-term benefit compared to placebo. [18,19] A 2023 systematic review found small effect sizes for leg pain reduction at 2-4 weeks but questionable clinical significance. [18] Meta-analyses show transforaminal approach may be marginally superior to interlaminar for radicular pain. [19]

Indications (Consider if):

• Persistent radicular pain > 6 weeks despite optimal conservative care
• Patient wishes to avoid or defer surgery
• No indication for urgent surgery (no CES, no progressive motor deficit)

Technique:

• Transforaminal: Targeted to specific nerve root; higher corticosteroid concentration at site
• Interlaminar: Easier access; less targeted

Outcomes:

• Moderate short-term pain reduction (mean VAS reduction 10-20mm at 2-6 weeks)
• May reduce need for surgery in subset of patients
• No proven benefit beyond 3 months

Risks:

• Infection (less than 0.1%)
• Dural puncture/headache (1-3%)
• Transient pain exacerbation
• Rare: epidural hematoma, nerve injury

Surgical Management

Exam Detail: Indications for Surgery:

Absolute (Emergency):

• Cauda equina syndrome (decompression within 24-48 hours) [9,10]

Relative:

• Intractable radicular pain > 6-12 weeks despite optimal conservative care
• Progressive or significant motor deficit (e.g., foot drop with muscle power less than 3/5)
• Patient preference after informed discussion (faster pain relief, but similar long-term outcome to conservative care)

Evidence:

• Surgery provides faster pain relief in first 6-12 months [12]
• By 1-2 years, no significant difference in outcomes between early surgery vs. prolonged conservative care [12]
• ~80-90% good-to-excellent outcomes after microdiscectomy at 1 year [20]
• Recurrence rate: ~5-10% requiring revision surgery

Clinical Pearl: Surgery vs. Conservative Care: Counseling Points

"Studies show that surgery provides faster pain relief in the first few months. However, by 1-2 years, patients who had surgery and those who continued with conservative care have similar outcomes. About 75-90% of patients improve without surgery within 6-12 weeks. Surgery is an option if your pain is intolerable, you have significant weakness, or you prefer faster relief after understanding the risks and benefits."

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9. Complications

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10. Prognosis and Outcomes

Natural History

Prognostic Factors

Exam Detail: Favorable Prognosis:

• Younger age (less than 40 years)
• Acute onset
• Single-level involvement
• Mild-moderate symptoms
• Good pre-morbid function
• Early mobilization and return to activity
• Positive coping strategies
• Job satisfaction

Unfavorable Prognosis (Chronicity Risk):

• Severe initial pain (VAS > 7/10)
• Prolonged symptom duration before presentation (> 3 months)
• Significant functional impairment at baseline
• Previous episodes
• Multilevel disc disease
• Obesity, smoking
• Psychological factors: depression, anxiety, catastrophizing, fear-avoidance behavior
• Secondary gain (litigation, disability benefits)
• Heavy manual occupation with poor job satisfaction

Post-Surgical Outcomes

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11. Prevention and Patient Education

Primary Prevention

Secondary Prevention (Preventing Recurrence)

• Education: Natural history, self-management, when to seek help
• Structured exercise program: Core stability, flexibility, gradual return to full activity
• Ergonomic modification: Workplace and home
• Weight loss if overweight
• Avoid prolonged sitting: Regular position changes
• Return to work planning: Graded, modified duties initially if heavy manual work

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12. Examination Focus (Viva Questions and Model Answers)

Exam Detail: Q1: A 45-year-old man presents with 3 days of severe right leg pain radiating to his foot. What are your key examination findings to confirm sciatica and determine the affected root level?

Model Answer: I would perform a structured neurological examination:

1. Inspection: Gait (foot drop? antalgic gait?), posture (list/scoliosis?)
2. Palpation: Tenderness over spine (midline suggests bone/disc; paraspinal suggests muscle)
3. Range of motion: Lumbar flexion/extension (limited ROM common)
4. Provocative tests:
   • Straight leg raise (positive less than 60° with leg pain = likely disc)
   • Crossed SLR (high specificity for disc herniation)
5. Neurological assessment by root:
   • Motor: L4 (knee extension), L5 (EHL/ankle dorsiflexion), S1 (plantarflexion)
   • Sensory: L4 (medial leg), L5 (first web space), S1 (lateral foot)
   • Reflexes: Knee jerk (L4), ankle jerk (S1)
6. Red flags: Check for saddle anesthesia, anal tone, bilateral symptoms (CES)

The pattern of weakness, sensory loss, and reflex changes localizes the root level.

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Q2: What are the indications for urgent MRI in a patient with sciatica?

Model Answer: Urgent MRI is indicated for red flag features:

1. Cauda equina syndrome: Saddle anesthesia, sphincter dysfunction (urinary retention/incontinence, fecal incontinence), bilateral leg symptoms
2. Progressive or severe motor deficit: Acute foot drop, rapidly worsening weakness
3. Suspected infection: Fever, night sweats, IVDU, immunosuppression, elevated inflammatory markers
4. Suspected malignancy: Age > 50, previous cancer, unexplained weight loss, night pain
5. Suspected fracture: Major trauma, minor trauma + osteoporosis

In uncomplicated sciatica without red flags, imaging can be deferred for 6 weeks to allow trial of conservative management.

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Q3: Explain the evidence for surgery versus conservative management in sciatica.

Model Answer: The evidence shows:

1. Natural history: 75-90% of patients with sciatica improve within 6-12 weeks with conservative care alone. [4,5]

2. Short-term (6 months): Surgery (microdiscectomy) provides faster pain relief and functional recovery compared to conservative care. Multiple RCTs demonstrate significant improvement in leg pain and disability by 6-12 weeks post-surgery. [12]

3. Long-term (1-2 years): There is no significant difference in outcomes between early surgery and prolonged conservative care. By 1-2 years, patients in both groups have similar pain scores and functional status. [12]

4. Implications:

   • Conservative management is first-line for uncomplicated sciatica (no red flags, no severe motor deficit)
   • Surgery is an option for patients with intractable pain > 6 weeks who prefer faster relief
   • Surgery is indicated for cauda equina syndrome (emergency) and progressive significant motor deficit

5. Shared decision-making: Patients should be informed that surgery offers faster relief but not necessarily better long-term outcomes, allowing them to weigh benefits and surgical risks.

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Q4: A patient with sciatica develops foot drop. What is your management approach?

Model Answer:

Immediate assessment:

1. Confirm L5 radiculopathy: Weakness of ankle dorsiflexion (tibialis anterior) and great toe extension (EHL); sensory loss in L5 distribution (first web space); no reflex change (no L5 reflex)
2. Severity: Grade power (MRC 0-5). Foot drop implies grade ≤3.
3. Acute vs. chronic: Recent onset (days) vs. longstanding (weeks/months)

Investigations:

• MRI lumbar spine (if not already done): Confirm L4/5 disc herniation compressing L5 root

Management:

• Acute foot drop (less than 2-4 weeks): Consider surgical decompression as motor deficit may be reversible if nerve compression is relieved early. Discuss urgently with spine surgeon.
• Chronic foot drop (> 3 months): Likely irreversible. Conservative: AFO (ankle-foot orthosis) to prevent tripping; physiotherapy.
• Supportive: Physiotherapy for gait training; falls prevention

Prognosis:

• Variable recovery depending on severity and duration of compression
• Early decompression improves likelihood of recovery
• Chronic severe foot drop may not fully recover

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Q5: Describe the features of cauda equina syndrome and why it is a surgical emergency.

Model Answer:

Cauda Equina Syndrome (CES) is compression of the cauda equina nerve roots, typically by a large central lumbar disc herniation (L4/5 or L5/S1).

Clinical Features:

• Bilateral leg pain/weakness/numbness
• Saddle anaesthesia (perianal, perineal, genital numbness - S2-S5 dermatomes)
• Sphincter dysfunction:
  • Urinary retention (painless bladder distension) or incontinence
  • Fecal incontinence or severe constipation
• Reduced anal tone on digital rectal examination
• Sexual dysfunction

Classification:

• CESI (incomplete): Urinary difficulties (hesitancy, frequency) but still voiding
• CESR (retention): Painless urinary retention; worse prognosis

Why a Surgical Emergency?

• Irreversible neurological damage if untreated
• Time-critical: Decompression within 24-48 hours improves outcomes [9,10]
• Delayed surgery (> 48 hours) results in higher rates of permanent bladder/bowel/sexual dysfunction

Management:

1. Urgent MRI (within hours)
2. Emergency surgical decompression (laminectomy ± discectomy)
3. Post-operative: Catheterization, bowel regime, pelvic floor physiotherapy, long-term multidisciplinary follow-up

Prognosis:

• Early decompression: 50-70% regain normal bladder function
• Delayed decompression: Permanent dysfunction common

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13. Patient / Layperson Explanation

What is sciatica?

Sciatica is pain that radiates along the path of the sciatic nerve, which runs from your lower back down through your buttock and into your leg. The pain typically affects one leg and often extends below the knee. It's caused by irritation or compression of nerve roots in your lower spine, most commonly due to a "slipped disc" (herniated disc).

What causes sciatica?

In 9 out of 10 cases, sciatica is caused by a herniated disc in your lower back. The discs are cushions between the bones of your spine. When a disc herniates, the soft inner material pushes out and presses on the nerve root, causing pain that radiates down your leg.

Other less common causes include spinal stenosis (narrowing of the spinal canal), spondylolisthesis (vertebra slipping forward), or muscle spasm (piriformis syndrome).

Will it get better?

Yes, in most cases. About 8-9 out of 10 people with sciatica get better within 6-12 weeks without needing surgery. The body often reabsorbs the herniated disc material over time, and inflammation settles.

What can I do to help myself?

1. Stay active: Although it may hurt, staying mobile helps recovery. Prolonged bed rest actually makes things worse. Try to continue with normal activities as much as tolerable.

2. Pain relief:

   • Over-the-counter painkillers like paracetamol or ibuprofen
   • Your doctor may prescribe medications for nerve pain (e.g., amitriptyline, gabapentin, pregabalin)

3. Heat/ice: Some people find heat packs or ice packs helpful for short-term relief.

4. Physiotherapy: A physiotherapist can teach you exercises to help with pain and prevent recurrence. Core strengthening and flexibility exercises are beneficial.

5. Avoid aggravating activities: Prolonged sitting, heavy lifting, and forward bending often worsen symptoms. Take regular breaks if you sit for long periods.

When should I see a doctor urgently?

Seek immediate medical attention if you develop:

• Loss of bladder or bowel control (incontinence or inability to urinate)
• Numbness in the genital/buttock area (saddle numbness)
• Weakness in both legs
• Severe or rapidly worsening leg weakness (e.g., foot drop - unable to lift your foot)

These symptoms may indicate cauda equina syndrome, a rare but serious complication that requires emergency surgery.

What about surgery?

Surgery is not usually needed. It is reserved for:

• Emergency situations (cauda equina syndrome)
• Severe, persistent pain that hasn't improved after 6-12 weeks of non-surgical treatment
• Significant muscle weakness

If you choose surgery, it can provide faster pain relief, but studies show that by 1-2 years, people who had surgery and those who didn't have similar outcomes. Your doctor will discuss whether surgery is right for you.

How can I prevent sciatica from coming back?

• Regular exercise: Keep your back and core muscles strong
• Maintain a healthy weight: Reduces stress on your spine
• Good posture: Especially when sitting and lifting
• Proper lifting technique: Bend your knees, keep the load close to your body, avoid twisting
• Quit smoking: Smoking impairs disc health and healing

Remember: Most people with sciatica recover well with time and self-care. Be patient, stay active, and seek help if symptoms worsen or red flag features develop.

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14. References

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2. Jensen RK, Kongsted A, Kjaer P, Koes B. Diagnosis and treatment of sciatica. BMJ. 2019;367:l6273. doi:10.1136/bmj.l6273

3. Konstantinou K, Dunn KM. Sciatica: review of epidemiological studies and prevalence estimates. Spine (Phila Pa 1976). 2008;33(22):2464-2472. doi:10.1097/BRS.0b013e318183a4a3

4. Vroomen PC, de Krom MC, Knottnerus JA. Predicting the outcome of sciatica at short-term follow-up. Br J Gen Pract. 2002;52(475):119-123.

5. Peul WC, van Houwelingen HC, van den Hout WB, et al. Surgery versus prolonged conservative treatment for sciatica. N Engl J Med. 2007;356(22):2245-2256. doi:10.1056/NEJMoa064039

6. van der Windt DA, Simons E, Riphagen II, et al. Physical examination for lumbar radiculopathy due to disc herniation in patients with low-back pain. Cochrane Database Syst Rev. 2010;(2):CD007431. doi:10.1002/14651858.CD007431.pub2

7. Huang W, Qian Y, Zheng K, Yu L, Yu X. Is smoking a risk factor for lumbar disc herniation? Eur Spine J. 2016;25(1):168-176. doi:10.1007/s00586-015-4103-y

8. Saal JS, Franson RC, Dobrow R, Saal JA, White AH, Goldthwaite N. High levels of inflammatory phospholipase A2 activity in lumbar disc herniations. Spine (Phila Pa 1976). 1990;15(7):674-678.

9. Lavy C, Marks P, Dangas K, Todd N. Cauda equina syndrome-a practical guide to definition and classification. Int Orthop. 2022;46(2):165-169. doi:10.1007/s00264-021-05273-1

10. Hoeritzauer I, Paterson M, Jamjoom AAB, et al.; Understanding Cauda Equina Syndrome (UCES) Study Collaborators. Cauda equina syndrome. Bone Joint J. 2023;105-B(9):1007-1012. doi:10.1302/0301-620X.105B9.BJJ-2022-1343.R1

11. Brinjikji W, Luetmer PH, Comstock B, et al. Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. AJNR Am J Neuroradiol. 2015;36(4):811-816. doi:10.3174/ajnr.A4173

12. Liu C, Ferreira GE, Abdel Shaheed C, et al. Surgical versus non-surgical treatment for sciatica: systematic review and meta-analysis of randomised controlled trials. BMJ. 2023;381:e070730. doi:10.1136/bmj-2022-070730

13. Hagen KB, Hilde G, Jamtvedt G, Winnem M. Bed rest for acute low-back pain and sciatica. Cochrane Database Syst Rev. 2004;(4):CD001254. doi:10.1002/14651858.CD001254.pub2

14. National Institute for Health and Care Excellence (NICE). Low back pain and sciatica in over 16 s: assessment and management. NICE Guideline [NG59]. November 2016. Updated December 2020.

15. Mathieson S, Maher CG, McLachlan AJ, et al. Trial of pregabalin for acute and chronic sciatica. N Engl J Med. 2017;376(12):1111-1120. doi:10.1056/NEJMoa1614292

16. Dove L, Jones G, Kelsey LA, Cairns MC, Schmid AB. How effective are physiotherapy interventions in treating people with sciatica? A systematic review and meta-analysis. Eur Spine J. 2023;32(2):517-533. doi:10.1007/s00586-022-07356-y

17. Lin LH, Lin TY, Chang KV, Wu WT, Özçakar L. Neural mobilization for reducing pain and disability in patients with lumbar radiculopathy: a systematic review and meta-analysis. Life (Basel). 2023;13(12):2255. doi:10.3390/life13122255

18. Verheijen EJA, Bonke CA, Amorij EMJ, Vleggeert-Lankamp CLA. Epidural steroid compared to placebo injection in sciatica: a systematic review and meta-analysis. Eur Spine J. 2021;30(11):3255-3264. doi:10.1007/s00586-021-06854-9

19. Manchikanti L, Knezevic E, Latchaw RE, et al. Comparative systematic review and meta-analysis of Cochrane review of epidural injections for lumbar radiculopathy or sciatica. Pain Physician. 2022;25(7):E889-E916.

20. Gadjradj PS, Harhangi BS, Amelink J, et al. Percutaneous transforaminal endoscopic discectomy versus open microdiscectomy for lumbar disc herniation: a systematic review and meta-analysis. Spine (Phila Pa 1976). 2021;46(8):538-549. doi:10.1097/BRS.0000000000003843