Links to other pages within Patient UK which are related to this topic:
Experience | Leaflets | Diagrams | Support | Patient+ | Weblinks | News | Products | Other
Print options:   Other options:   Bookmark and Share

This is a PatientPlus article. PatientPlus articles are written for doctors and so the language can be technical. However, some people find that they add depth to the articles found in the other sections of this website which are written for non-medical people.

Sciatic Nerve and Sciatica

Post your experience
See others (11 there)
Definition1
  • Sciatica refers to symptoms arising from entrapment of lumbar spinal nerve roots. The symptoms are pain, tingling and numbness in the distribution of lumbar nerve roots - the buttocks, thigh, outer calf, foot and toes. Symptoms in sciatica typically extend to below the knee.
  • The terms 'nerve root pain' or 'radicular pain' are also used for sciatica.
  • Sciatica may occur together with non-specific low back pain. In this situation, the sciatica symptoms are usually the main problem.
Epidemiology2

Sciatica is a common problem. The lifetime prevalence of low back pain is 50-70%, and 5-10% of patients with low back pain have sciatica.

Anatomy and pathology

For illustration of spinal anatomy and pain mechanisms, see reference.3

Spinal nerve roots are identified by the number of the lower of the two vertebra between which they pass. For example, the L5 nerve root passes between the 4th and 5th lumbar vertebrae.1

Aetiology1,4

Sciatica occurs when there is compression of lumbosacral nerve root(s), which may have various causes:

  • Herniation of a lumbar intervertebral disc.
    • Most commonly occurs at the L5 or S1 levels
  • Annular fissure of intervertebral disc with chemical irritation of nerve root.
  • Osteophytic nerve root compression.
  • Spinal stenosis - narrowing of the spinal canal.
    • Causes of spinal stenosis include:
      • Facet joint osteoarthrosis
      • Congenital stenosis
      • Spondylolisthesis - a vertebra slips forward relative to the lower vertebrae
    • Note: lateral recess stenosis and foraminal stenosis tend to cause sciatica. In contrast, central spinal stenosis tends to cause spinal claudication i.e. symptoms of bilateral calf pain, paraesthesia, or numbness on walking (see differential diagnosis)
  • Injury.
    • Fracture or displacement impinging on the spinal nerves
    • Remember that in osteoporotic patients fractures can occur with minor trauma
  • Bone or joint disease, e.g. Paget's disease, ankylosing spondylitis.
  • Infection:
  • Spinal tumours, e.g. bony secondaries from breast or prostate cancer and myeloma.
  • Failed back surgery syndrome, e.g. recurrent herniation, epidural adhesions or arachnoiditis.
  • Epidural varicose veins (rare) due to inferior vena cava obstruction from pregnancy or abdominal mass.5
Presentation1

Typical features are:

  • Unilateral leg pain radiating to below the knee.
  • Back pain (if present) is less severe than leg pain.
  • Symptoms/signs of nerve root compression: numbness, tingling (paraesthesia), weakness, or loss of tendon reflexes.
  • Straight leg raising test increases the leg pain and/or the nerve compression symptoms.
Assessment1

1. Assess for 'red flags'

  • Do a history and examination for 'red flag' features, which may indicate cauda equina syndrome, fracture, spinal infection or cancer (see box below).
  • Those with cauda equina syndrome need immediate referral to prevent permanent neurological damage. Other red flag features may need same day or urgent (within a few days) referral, depending on the clinical situation.

Red flags in history and examination of sciatica and low back pain

History:

  • Cauda equina red flags:
    • Saddle anaesthesia - sensory loss in buttocks, genitalia or perineum
    • Sphincter dysfunction (difficulty with micturition or defaecation, loss of bladder or bowel control due to loss of sensation)
    • Impotence
    • Progressive weakness
    • Bilateral symptoms
  • Fracture red flags are:
    • Major trauma, e.g. road accident
    • Minor trauma (even strenuous lifting) in people with osteoporosis
    • Sudden onset of severe central pain in the spine which is relieved by lying down
  • Infection or cancer red flags are:
    • Age <20 or >50 years
    • History of cancer, immune suppression, intravenous drug abuse or recent bacterial infection
    • Pain that persists when supine, night pain disturbing sleep or thoracic pain (thoracic pain may also suggest aortic aneurysm)
    • Systemic symptoms, e.g. fever, chills, or unexplained weight loss

Examination:

  • Cauda equina signs are:
    • Urinary retention
    • Perianal or perineal sensory loss
    • Lax anal sphincter
    • Severe or progressive neurological deficit in the lower extremities
    • Major motor weakness with knee extension, ankle eversion, or foot dorsiflexion
  • Spinal deformity indicates possible fracture, infection or cancer

2. Confirm diagnosis of sciatica

Typical history is:

  • Unilateral leg pain radiating below the knee to the foot or toes.
  • Any low back pain is less severe than the leg pain.
  • Symptoms of nerve root compression: numbness, tingling (paraesthesia), weakness, or loss of tendon reflexes.

Examination:

  • Sensory loss, weakness, or loss of tendon reflexes in a nerve root distribution.
  • Straight leg raising test increases leg pain and/or nerve compression symptoms.
  • Look for other causes of pain:
    • Check hips, knees and trochanteric bursae.
    • Further examination (e.g. abdomen, pelvis, aorta) if appropriate.

Straight leg raising test6

This is widely used to help diagnose nerve root pain. It has high sensitivity (about 91%) but low specificity (about 26%) for diagnosing nerve root pain due to herniated discs.2

  • The patient lies flat on their back with both legs straight.
  • Raise one leg until limited by pain and/or tight hamstrings. Slightly lower the leg to provide relief.
  • In this position, increase tension on the sciatic nerve by dorsiflexion of the foot (or flexion of the neck or compression of the nerve in the popliteal fossa). This will aggravate or elicit pain radiating down the raised leg if there is nerve root irritation. The pain should be relieved by flexion of the knee.
  • Nerve root pain generally occurs at 30-70° of straight leg raising6 (below 30° the sciatic nerve is not stretched).

Differential diagnosis1,6
  • Sacroiliitis (ankylosing spondylitis and other spondyloarthropathies). With arthropathies the pain may alternate between buttocks.
  • Spinal claudication i.e. bilateral calf pain, paraesthesia, or numbness on walking, relieved by sitting, worse on spine extension, usually negative straight leg raising test and few neurological signs.
  • Other neurological problems or thoracic spine lesions (usually have more widespread neurological features).
  • Shingles (before the rash appears).
  • Causes outside the spine:
    • Lower limb: pain from hip, knee or trochanteric bursa, peroneal nerve palsy (nerve entrapment at the fibular head).
    • Thoracic or abdominal pathology, e.g. aortic aneurysm, abdominal tumours.
    • Pelvic lesions, e.g. psoas muscle abscess, pelvic tumours or inflammation; pelvic fractures (may irritate pelvic nerves).
    • Piriformis syndrome (entrapment of the sciatic nerve in the piriformis muscle) and other pelvic nerve entrapments.7,8
    • Trauma around the sciatic nerve, e.g. misplaced gluteal muscle injection or gluteal muscle compartment syndrome.9
Investigations

Investigations are needed if there are 'red flag' features, or if surgery is considered.1 Possible investigations include:

  • Blood tests: full blood count, ESR/CRP, renal and liver function, bone profile, PSA, serum protein electrophoresis
  • Urine tests if suspected infection or cancer: urine dipstick, microscopy and culture; urine Bence Jones protein
  • Radiology: possible tests are:
    • Plain X-ray of lumbosacral spine (and thoracic spine, if thoracic pain also present)
    • CT or MRI scan
    • Bone scan
Initial management1

Patient information

Provide information and advice to promote understanding, a positive attitude and realistic expectations. Suggested points to discuss are:

  • Explain diagnosis and any concerns. Sciatica often settles by 6–12 weeks.
  • Temporary pain relief can be used.
  • Recovery is helped by getting moving again and getting back to work as soon as possible.
  • Advise when to seek help (progressive symptoms or red flag symptoms).
  • Care when lifting and twisting.
  • Cold or heat packs can relieve back pain.
  • When lying down, it may help to use a small pillow between the knees (if sleeping on the side), or several pillows propping up the knees (when lying on the back).

Drug treatment

  1. First-line: simple analgesics - paracetamol or ibuprofen.
  2. For additional analgesia:
    • Combine paracetamol and an NSAID, or
    • Add a weak opioid (e.g. codeine or tramadol).
  3. For persistent sciatica not responding to first-line analgesics:

When to refer

  • Red flags: cauda equina syndrome needs immediate referral, other red flags need urgent referral (see Assessment above).
  • If neurological deficit is progressive, persistent, or severe, refer for neurosurgical or orthopaedic assessment (preferably to be seen within 1 week).
  • If pain or disability remain problematic for >1-2 weeks, consider early referral for physiotherapy or other physical therapy.
  • If sciatica is disabling and distressing for >6 weeks, refer for neurosurgical or orthopaedic assessment - preferably to be seen within 3 weeks.
  • If pain or disability are problematic despite appropriate pharmacotherapy and physical therapy, consider referral to a multidisciplinary back pain service or a chronic pain clinic.
Further management

Follow-up

  • This depends on the clinical situation.
  • Consider 'yellow flags' for chronicity, which are:
    • Belief that pain and activity are harmful; sickness behaviours, such as extended rest.
    • Social withdrawal, lack of support or overprotective family
    • Emotional problems, e.g. negative mood, depression, anxiety.
    • Problems at work; long time off work (>6 weeks).
    • Problems with compensation claims or benefits.
    • Inappropriate expectations of treatment, e.g. not expecting active participation in treatment.

Surgery and other treatments

Decisions about invasive management should be balanced against the natural history and relatively good prognosis of sciatica (see prognosis). Multidisciplinary care, such as back clinics or pain clinics, may be useful.

Possible procedures include:

  • Epidural steroid injection:4
    • This can provide short-term pain relief; the longer-term benefits are uncertain.
    • It should be performed under fluoroscopy with contrast for best results.
  • Surgery:
    • May be required for major pathology, e.g. fractures, neurological deficit, tumours or infections.
    • May be beneficial for spinal stenosis and spondylolisthesis, compared to non-surgical treatment.
    • For disc herniation, without severe neurological deficit, surgery may promote more rapid return to function compared to the natural course of sciatica.
    • The benefits of surgery vs. conservative treatment are still debated.10 Some studies suggest good results from surgery.10 However, 'failed back surgery syndrome' is a recognised complication, where there may be recurrent herniation, epidural adhesions or arachnoiditis.4
    • The standard surgical procedures are discectomy or microdiscectomy - the latter uses magnification to view the disc and nerves during surgery. A recent Cochrane review11 of these procedures found that results are comparable between discectomy and microdiscectomy; the choice mainly depends on local expertise.

New treatments and research

  • Various minimally invasive surgical techniques have been developed as alternatives to open discectomy. Currently these are regarded as research techniques, until more data is available on their safety and effectiveness:11
    • Percutaneous intradiscal electrothermal therapy.12
    • Automated percutaneous mechanical lumbar discectomy.13
    • Endoscopic laser foraminoplasty.14
    • Laser lumbar discectomy.15
  • Injection of oxygen-ozone mixture gas into the disc and foramen is a new technique which shows promise. The mixture is thought to dry out the disc, reduce inflammation and improve local microcirculation.16,17
  • Antibodies against tumour necrosis factor-alpha have been researched, because of the possible causative role of this factor in sciatic pain. Some small trials have used infliximab18 or etanercept,16 but with no clear benefit so far.
Complications1

Possible complications include:

  • Permanent nerve damage with sensory deficits and, more importantly, motor weakness.
  • Chronic pain and psychosocial problems.
  • Loss of employment.
Prognosis1

The prognosis for acute sciatica is generally favourable:

  • In placebo groups of people with acute sciatica (included in randomised trials of non-surgical interventions), about 50% reported improvement within 10 days, and about 75% reported improvement after 4 weeks.1
  • The herniated portion of an intervertebral disc causing sciatica tends to regress over time, with about two thirds having at least partial resolution after 6 months.
  • Up to 30% of people continued to have pain for 1 year or longer. Improvement in symptoms may continue beyond one year.
Prevention
  • Improved general fitness and posture.
  • 'Back school' – advice on lifting techniques, advice on coping with pain.
  • Occupational therapy and job retraining if these activities precipitate attacks.


Document references
  1. Back pain (low) and sciatica, Clinical Knowledge Summaries (September 2008)
  2. Koes BW, van Tulder MW, Peul WC; Diagnosis and treatment of sciatica. BMJ. 2007 Jun 23;334(7607):1313-7.
  3. Gangi A, Dietemann JL, Mortazavi R, et al; CT-guided interventional procedures for pain management in the lumbosacral spine. Radiographics. 1998 May-Jun;18(3):621-33. [abstract]
  4. Cohen SP, Argoff CE, Carragee EJ; Management of low back pain. BMJ. 2008 Dec 22;337:a2718. doi: 10.1136/bmj.a2718.
  5. Paksoy Y, Gormus N; Epidural venous plexus enlargements presenting with radiculopathy and back pain in patients with inferior vena cava obstruction or occlusion. Spine. 2004 Nov 1;29(21):2419-24. [abstract]
  6. Speed C; Low back pain. BMJ. 2004 May 8;328(7448):1119-21.
  7. Filler AG, Haynes J, Jordan SE, et al; Sciatica of nondisc origin and piriformis syndrome: diagnosis by magnetic resonance neurography and interventional magnetic resonance imaging with outcome study of resulting treatment. J Neurosurg Spine. 2005 Feb;2(2):99-115. [abstract]
  8. Kuncewicz E, Gajewska E, Sobieska M, et al; Piriformis muscle syndrome. Ann Acad Med Stetin. 2006;52(3):99-101; discussion 101. [abstract]
  9. Roth JS, Newman EC; Gluteal compartment syndrome and sciatica after bone marrow biopsy: a case report and review of the literature. Am Surg. 2002 Sep;68(9):791-4. [abstract]
  10. Peul WC, van den Hout WB, Brand R, et al; Prolonged conservative care versus early surgery in patients with sciatica caused by lumbar disc herniation: two year results of a randomised controlled trial. BMJ. 2008 Jun 14;336(7657):1355-8. Epub 2008 May 23. [abstract]
  11. Gibson JN, Waddell G; Surgical interventions for lumbar disc prolapse: updated Cochrane Review. Spine. 2007 Jul 15;32(16):1735-47. [abstract]
  12. Percutaneous intradiscal electrothermal therapy, NICE (2004)
  13. Automated percutaneous mechanical lumbar discectomy, NICE (2005)
  14. Endoscopic laser foraminoplasty, NICE (2003)
  15. Laser lumbar discectomy, NICE (2003)
  16. Muto M, Andreula C, Leonardi M; Treatment of herniated lumbar disc by intradiscal and intraforaminal oxygen-ozone (O2-O3) injection. J Neuroradiol. 2004 Jun;31(3):183-9. [abstract]
  17. Gallucci M, Limbucci N, Zugaro L, et al; Sciatica: treatment with intradiscal and intraforaminal injections of steroid and oxygen-ozone versus steroid only. Radiology. 2007 Mar;242(3):907-13. Epub 2007 Jan 5. [abstract]
  18. Korhonen T, Karppinen J, Paimela L, et al; The treatment of disc-herniation-induced sciatica with infliximab: one-year follow-up results of FIRST II, a randomized controlled trial. Spine. 2006 Nov 15;31(24):2759-66. [abstract]

Internet and further reading Acknowledgements EMIS is grateful to Dr N Hartree for writing this article. The final copy has passed scrutiny by the independent Mentor GP reviewing team. ©EMIS 2009.
Document ID: 2754
Document Version: 21
Document Reference: bgp1163
Last Updated: 25 Mar 2009
Planned Review: 25 Mar 2011

The authors and editors of this article are employed to create accurate and up to date content reflecting reliable research evidence, guidance and best clinical practice. They are free from any commercial conflicts of interest. Find out more about updating.

Patient UK Hearing Impairment Survey

Patient UK are grateful to the 550 people who took part in this survey.
To see the results click here.
If you'd like to leave your feedback, please go to our interactive forum.

Links to other pages within Patient UK which are related to this topic:
Experience | Leaflets | Diagrams | Support | Patient+ | Weblinks | News | Products | Other
Print options:   Other options:   Bookmark and Share
Want to search some more? Use the Google Search box below to search our site.

Related pages in Patient UK

Your Experience (^ top of page)

 Please add your experience about this condition / medicine
 View Patient Experience for 'Sciatica' (11 there)
 Back Pain (Non-specific)

 Dermatomes - leg (diagram)

Support Group BackCare
Support Group Total Back Care Centre

 Assessment and Management of Low Back Pain
 Back Manipulation
 Back Pain - Non Sinister Causes
 Backache and its Assessment
 Neurological Examination of the Lower Limbs
 Neuropathic Pain and its Management
 Sinister causes of Back Pain
 Spinal Disc Problems (including Red Flags Signs)

 Back Pain and Sciatica

Recent related news items

 Pain relief patch advert banned
 Patients forced to live in agony after NHS refuses to pay for painkilling injections
 A slipped disc left TV's Kate Silverton in agony - and with a very embarrassing problem
 Exercise therapy
 Ask the doctor: What can I do about my chronic sciatica?

All news by related topic

 Sciatica news
 Lumbar Back Pain news

Online Pharmacy

 Algesal Local Analgesic Cream
 Alka-Seltzer Original Tablets 20 tablets
 Alka-Seltzer XS Tablets 20 tablets
 Anadin Extra Tablets 32 tablets
 Anadin Original Tablets
 Anadin Tablets
 Aspirin Dispersible Tablets 300mg
 Aspro Clear Tablets
 Codis 500 Tablets
 Deep Heat Heat Spray
 Deep Heat Patch
 Deep Heat Rub 35g
 Deep Heat Rub 67g
 Disprin Direct Chewable Asprin
 Nurofen Plus Ibuprofen and Codeine Tablets 32
 Solpadeine Max Tablets

Medical equipment

 Back Care

Visit the Patient UK Medical Equipment shop

Books

 Back Pain (Understanding)
 Back Pain : British Medical Association's Family Doctor Series
 Backache (The Daily Telegraph): A Complete Guide to Relief

Visit the Patient UK shop

Other - Useful resources (^ top of page)

Pictures, diagrams, photos, images, etc.
Evidence based medicine
Online textbooks and journals
UK Guidelines
Online Videos
Medline
Other good health sites

Want to search some more? Use the Google Search box below to search our site.

Advertisements











Disclaimer: Patient UK has no control over the content of any external links above. Inclusion does not imply endorsement by Patient UK.

Want to advertise on this site? Find out how >>

Clicking here will take you to the foot of this page where you'll find a list of Information Leaflets which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Support Groups which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Medicines & Drugs which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of diagrams which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of PatientPlus (detailed reference) articles which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of UK Guidelines which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of other selected websites which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Poems and Stories which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Operations and Procedures which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Online Videos which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find links through to our interactive forum.
Here you can follow a link to view existing patient experiences on this subject, or to add your own
Clicking here will take you to the foot of this page where you'll find links to news stories on this subject in our Online Newspaper
Clicking here will take you to the foot of this page where you'll find links to related products
Clicking here will take you to the foot of this page where you'll find links to other useful sources of information
Click here to open a printer-friendly version of this document, in a new window, together with the print dialogue box
Click here to open this document in PDF format
This will offer you the usual PDF options i.e. document navigation, search, zoom and formatted print
Note: this is the best way to print the document
Click here to listen to the MP3 audio recording of this document
Click here to download the audio recording of this document as a podcast, for listening to at your leisure
Click here to open our Dictionaries and Glossaries page
Click here to see related products in our Online Pharmacy
Note: this will open in a new window
Click here to add this page to a social bookmarking site of your choice
Click here if you want to find out more about social bookmarking. This link will take you to the Wikipedia explanation
Note: this will open in a new window
Clicking here will take you to the foot of this page where you'll find a list of Information Leaflets which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Support Groups which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Medicines & Drugs which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of diagrams which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of PatientPlus (detailed reference) articles which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of UK Guidelines which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of other selected websites which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Poems and Stories which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Operations and Procedures which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find a list of Online Videos which are related to the topic you are currently viewing
Clicking here will take you to the foot of this page where you'll find links through to our interactive forum.
Here you can follow a link to view existing patient experiences on this subject, or to add your own
Clicking here will take you to the foot of this page where you'll find links to news stories on this subject in our Online Newspaper
Clicking here will take you to the foot of this page where you'll find links to related products
Clicking here will take you to the foot of this page where you'll find links to other useful sources of information
Click here to open a printer-friendly version of this document, in a new window, together with the print dialogue box
Click here to open this document in PDF format
This will offer you the usual PDF options i.e. document navigation, search, zoom and formatted print
Note: this is the best way to print the document
Click here to listen to the MP3 audio recording of this document
Click here to download the audio recording of this document as a podcast, for listening to at your leisure
Click here to open our Dictionaries and Glossaries page
Click here to see related products in our Online Pharmacy
Note: this will open in a new window
Click here to add this page to a social bookmarking site of your choice
Click here if you want to find out more about social bookmarking. This link will take you to the Wikipedia explanation
Note: this will open in a new window
Click here to return to the home page
Click here to read our 'About Us' page
Go to the Emis Access website, where you can book an appointment with your GP, order a repeat prescription or view you medical record online.
Note: this will open in a new window
View and/or join in discussion about health, lifestyle and disease in our interactive forum.
Note: this will open in a new window
Visit our pharmacy product price comparison website
Go to our online newspaper for current medical news and commentary.
Note: this will open in a new window
Adverts on this site do not influence the medical content. Click to read more.
Adverts on this site do not influence the medical content. Click to read more.