Sciatica is often used to describe pain travelling from the lower back into the buttock or leg. Sciatica isn’t a diagnosis in itself, but a term used to describe symptoms associated with irritation of the sciatic nerve or the nerve roots which form it.
There are several possible causes, and not all pain travelling into the leg is actually coming from the sciatic nerve.
Is sciatica always caused by a trapped nerve?
A ‘trapped nerve’ is a simplified description. Symptoms can occur because of irritation or compression of a nerve root in the lower back, narrowing around the nerve, or sometimes because problems elsewhere produce very similar symptoms.
Simon Barnes, Chartered Physiotherapist, explains:
“I like to think of the sciatic nerve a little like a hosepipe. If you put your foot on the hosepipe, you compress it. Something similar can happen to a nerve, for example as a result of a disc prolapse or bulge in the lower back.
“But you can also get a kink in the hosepipe rather than something pressing directly down on it. Problems around the nerve further along its course, particularly around the buttock, can sometimes irritate the nerve or produce symptoms which feel very similar to sciatica. Muscles such as the piriformis, gluteus minimus and gluteus maximus can all be involved in producing these sciatic-type symptoms. This is sometimes referred to as ‘pseudo-sciatica’.”
Disc problems in the lower back
Problems involving one of the discs in the lower back are a common cause of sciatica.
A disc bulge or prolapse can irritate or compress a nearby nerve root. This can cause pain travelling from the back or buttock into the leg and may also be accompanied by pins and needles, numbness or weakness.
Symptoms from a disc problem can settle as inflammation reduces and the disc changes over time. Disc changes are also very common, including in people without any pain, so finding a disc bulge on a scan doesn’t necessarily mean that it is responsible for someone’s symptoms.
Arthritis and changes in the lower back
Changes to the joints and other structures in the lower back can sometimes reduce the space available around a nerve or irritate nearby structures.
These changes become increasingly common as we get older, but their presence doesn’t automatically mean that they are the cause of your pain.
Spinal stenosis
Spinal stenosis describes narrowing within the spinal canal or around the nerve roots.
This can cause leg pain, heaviness, tingling or weakness, often particularly with standing or walking. Some people find their symptoms improve when sitting down or bending forwards.
Can piriformis syndrome cause sciatica?
The sciatic nerve passes through the buttock close to the piriformis muscle. Irritation in this region can sometimes produce symptoms resembling sciatica.
Problems involving other muscles around the buttock, including gluteus minimus and gluteus maximus, can also produce referred pain which may feel very similar to sciatic pain.
Can hip problems feel like sciatica?
Yes. Problems arising from the hip and surrounding structures can sometimes cause pain in the buttock, thigh or leg which may initially be mistaken for sciatica.
This is one reason why looking at where you feel the pain alone isn’t always enough to determine what is causing it.
How do you know what is causing your sciatica?
A thorough assessment of your symptoms and physical examination can help to establish the likely source of your pain. This may include looking at:
- Where you feel the symptoms
- What movements or positions aggravate or relieve them
- Strength, sensation and reflexes where appropriate
- Movement in your back and hip
- Whether your symptoms behave more like nerve pain or referred musculoskeletal pain
- How your symptoms respond when your lower back, hip and surrounding muscles are examined and moved
Because the treatment approach differs depending on the underlying cause, working out the likely source of your symptoms is often one of the most important parts of your recovery.
When should you seek medical advice urgently?
If you have low back pain or sciatica accompanied by any of the following symptoms, you should seek urgent medical assessment rather than waiting for a Physiotherapy appointment:
- New problems controlling your bladder or bowels
- Numbness or altered sensation around the saddle or genital area
- Significant or increasing weakness in your leg or legs
If you develop these symptoms, contact NHS 111 for advice or attend A&E where appropriate.
What should you do if you think you have sciatica?
If you are experiencing pain travelling from your back or buttock into your leg but none of the urgent symptoms described above, a physiotherapy assessment can help establish what may be causing your symptoms and the most appropriate way to manage them.
You can find out more on our Sciatica page, including symptoms, assessment and how physiotherapy may help.
At Corsham Physiotherapy, we assess and treat people with sciatica and lower back pain from Corsham, Chippenham, Bath and the surrounding Wiltshire area.
