Sciatica is not actually a diagnosis but rather a general term that is used when there is an irritation or problem with the sciatic nerve. The Sciatic Nerve is the longest and widest nerve in the human body that’s formed by the exiting nerve roots of L4-S3. It runs from the lower back down deep into the buttocks, down the back of the thigh before dividing into smaller branches at the level of the knee and continuing down into the back of the lower leg, ankle and foot.
If you are experiencing ‘sciatica’ that literally means you have pain anywhere along the length of the sciatic nerve. Remembering also that the sciatic nerve has a large sensory input so someone with ‘sciatica’ could also experience tingling, numbness or burning in their leg. Symptoms can vary in severity, change throughout the day and be aggravated by different positions.
You can start to see how ‘Sciatica’ itself can represent a vast set of symptoms and it then becomes my job as a physio to try and find the underlying cause.
What are the potential causes?
To try and put it simply anything that compresses or irritates the Sciatic Nerve either at the level of the spine or along its course. A few common examples could include
Herniated Disc: A weakening or bulge of an intervertebral disc (these are the shock absorbers that sit between each vertebrae). If this bulge extends out far enough it can touch or compress the exiting nerve root. This is the most common cause of Sciatica
Degenerative Disc Disease: As we age our discs can begin to get thin and wear away. As this happens the space between each vertebra narrows which in turn can put pressure on the exiting nerve root
Spinal Stenosis: This is a narrowing of the space that the spinal cord and spinal nerves sit in which again creates compression on the nerve roots. This can happen with age.
Osteoarthritis and the development of osteophytes which are extra bony growths that can develop on the vertebrae. These growths can irritate the exiting nerve root.
What can be done?
Management of sciatica will be based on what is causing your particular symptoms. You physio or health practitioner should take a thorough history and perform a series of tests to look at how you move into certain positions and if certain tasks aggravate your symptoms. We are looking for restrictions, deficits in strength, altered sensation among other things that may point us to exactly where that nerve is being compressed. In some cases further investigation via MRI may be warranted.
Then what? The good news is that most people with sciatic will respond to conservative treatment. This will generally involve soft tissue therapy and exercise prescription which may include a variety of strengthening and stretching exercises. There are medications and alternative treatment options that can be discussed with your medical practitioner where warranted.
For the majority of sciatica sufferers symptoms will settle in 4-6 weeks with the correct management.