Sciatica refers to leg pain secondary to lumbosacral nerve root entrapment and is an equivalent term to radicular pain or radiculopathy.

Establish history of back pain

Onset, duration, severity and screen for: cauda equina syndrome, tumour, infection, major neurological deficit, osteoporotic collapse and inflammatory disease (ankylosing spondylitis). 

Exclude Red Flag features

Cauda equina syndrome

Severity (affecting motor function at knee and ankle)

Cauda equina syndrome

Rapidly progressive or bilateral sciatica

Cauda equina syndrome

Urinary or bowel incontinence, perianal anaesthesia, lax anal sphincter

Cauda equina syndrome

Hyper-reflexia, clonus, extensor plantar response

Sudden onset severe central spinal pain with antecedent trauma or known osteoporosis

Osteoporotic or traumatic vertebral fracture

Spinal cancer or metastatic spinal cord compression

Severe, unremitting (not alleviated by lying down or sleep or precipitated by defecation straining) with antecedent cancer diagnosis or unexplained weight loss

Localised (point) vertebral body tenderness and/or thoracic pain

Spinal traumatic fracture or malignancy

Epidural abscess or vertebral osteomyelitis

Fever, immunosuppressed (HIV, diabetes), raised inflammatory markers

Pain disturbing sleep,thoracolumbar or sacroiliac pain, marked morning stiffness, peripheral joint involvement, systemic involvement (iritis, psoriasis, colitis), preceding infective diarrhoea or sexually transmitted infection, family history of spondylitis 

Ankylosing spondylitis

Assessment

• Straight leg raising
• Mapping dermatomes
• Consider using Keele University STarT Back screening tool to stratify non-specific LBP according to prognostic risk

Imaging

• No requirement to routinely offer imaging in non-specialist setting.
• Consider imaging in specialist setting if the result is likely to change management (such as osteoporotic vertebral fracture)

Management

• Exercises (group exercise programme)
• Manual therapy by physiotherapy: spinal manipulation, mobilisation or soft tissue techniques such as massage
• Psychological therapy
• NSAIDs (ensure gastoprotection), weak opioids
• If chronic neuropathic pain, consider pregabalin or gabapentin
• Consider diazepam (2mg TDS, 5 days) if evidence of paraspinal muscle spasm (absence of strong evidence to support practice)

Referral (check local commissioned services)

• 'Red Flags' and/or acute radiculopathy: rapid access to MRI (or CT if MRI contraindicated)
• Epidural injection of local anaesthetic and steroid for cases of acute and severe sciatica
• Medial branch nerve block and/or radiofrequency denervation for pain involving structures supplied by medial branch nerve
• Surgery: spinal decompression for sciatica and/or spinal fusion
• Cauda equina syndrome: lumbar spinal decompression and discectomy. This is performed posteriorly and involves decompression of the nerves and removal of fragments of disc compressing the nerves

Safety net advice

• Advise patient to seek follow up in 1-2 weeks if symptoms persist or worsen
• Advise patient to report any Red Flag symptoms and signs

References

Low back pain and sciatica in over 16s: assessment and management. NICE guidelinePublished: 30 November 2016.

National Low Back Pain and Radicular Pain Pathway. 2017

Patient information leaflet