What is sciatica?
Sciatica is pain that radiates from the lower back down into the legs, that results from pressure on the sciatic nerve. The pressure usually comes from a herniated disk, a bone spur on the spine, or narrowing of the spine.
Sciatica usually affects one side of the body, causing a sharp shooting pain down one leg. The frequency and duration of the pain varies from person to person, with some individuals experiencing intermittent bursts, while others feel pain more or less constantly. Most cases of sciatica can be resolved within a few weeks, but for some individuals, it is a debilitating long-term condition.
The pain associated with sciatica varies from person to person. People with sciatica may experience one or more of the following:
- The pain starts in the lower back, travels down the buttock and goes into the back of the thigh and calf. Some parts of this neural pathway might be affected more severely than others.
- Sciatica generally affects only one side of the body, but in rare severe cases, both legs can be affected.
- Sciatica usually lasts for a few weeks, and the episodes of pain during this time can vary. Sometimes the pain will be limited to a mild ache; other times it will feel like an electric shock or a searing sensation.
- Some people with sciatica experience numbness or tingling in the affected leg.
- Sometimes the pain starts or worsens with no obvious trigger; other times, it can flare up after physical activity or long periods of inactivity.
- More severe cases of sciatica are accompanied by muscular weakness in the affected leg.
- In extreme cases, people with sciatica can have trouble controlling their bladder or bowels.
What causes sciatica?
Sciatica is caused by pressure on the sciatic nerve, which runs from the lower back down into the legs. The compression can be caused by a number of things, including the following:
- A herniated disk or a bone spur on the spine, both of which are more common in older people
- A tumour
- Excess body weight that increases the pressure on the spine
- Long periods of inactivity
- Occupations that require heavy lifting, twisting of the spine or driving for long stretches
- Diabetes, which can increase the risk of nerve damage