Health Knowledgebase

Sciatica

20th February, 2009 - Posted by ross -

Diagram of Sciatic nerve

Sciatica is the term for pain down the back of the leg, typically occurring along the course of the sciatic nerve.

This large nerve is composed of several nerve roots which originate from the spinal cord at various levels in the lower lumbar spine. The nerve roots unite at the lumbosacral plexus to form the sciatic nerve which courses posterior to the hip joint and passes down the back of the leg, giving off nerve branches as it descends.

Sciatica can occur as a result of compression or irritation of the sciatic nerve at any point along its course. The most common cause of sciatica is a prolapsed intervertebral disc. The disc prolapse most often occurs in the lumbar spine, often but not always in the lower lumbar region. The disc prolapse (disc herniation or “slipped disc”) may result in compression of one or more lumbar nerve roots (which contribute to the sciatic nerve) and this nerve root compression results in sciatica. Although the pain is felt radiating down the back of the leg, the source of the pain is usually, but not always, in the back. With sciatica, there may or may not be associated back pain. Compression of a lumbar nerve root giving rise to sciatica may be due to causes other than a disc prolapse. It may be due to osteophyte (new bone) impingement (the osteophyte formation arising due to degenerative disc disease) and may also occur as a complication of facet joint arthritis. The facet joints are small joints between the posterior elements of adjacent vertebrae.

Treatments

Sciatica can be of variable intensity ranging from mild to very severe. If symptoms are mild they may respond to simple pain killers/analgesics such as paracetemol. If symptoms are more severe and persistent, professional advice from your GP is required.

Treaments may include stronger analgesics, available from an online chemist if appropriate, bed rest, and physiotherapy. Your GP may suggest an X-Ray or other form of imaging/scan depending on the clinical history and examination. In the majority of instances symptoms will settle down over a period of time. The natural history of a disc prolapse is that in the majority of cases it will reduce in size and symptoms will disappear. However, if symptoms are very intense and unremitting, or if symptoms are perhaps milder but interfering with everyday life, your doctor may refer you to a specialist for a further opinion and advice concerning the need or otherwise for surgery.

Further references

www.backdoctor.org.uk
http://en.wikipedia.org/wiki/Sciatica
www.bbc.co.uk/health/conditions/sciatica1.shtml
www.sciaticaclinic.com