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Causes
The sciatic nerve is the main nerve in the leg and the largest nerve in the body. It runs from the base of the spine, along the back of the thigh to the knee, where it divides into branches.
Sciatic pain is usually caused by compression of this nerve at the point where it leaves the spine. Damage to the nerve can also cause pain.
In young and early middle-aged adults, the most common cause of sciatica is a prolapsed disc. In older people, changes in the spine due to conditions such as osteoarthritis may be responsible.
Sometimes, sitting awkwardly can cause sciatica. Avoiding sitting in awkward positions for long periods of time. Taking regular exercise can help to reduce the risk.
Symptoms
Sciatica usually only affects one leg. The pain may be felt in the buttock, down the back of the leg, below the knee and in the foot. Such pain can be mild or severe; it may be persistent or come in spasms.
Sufferers may also experience numbness, tingling and muscle weakness in the affected leg. Sciatica can be worse when you cough or move, and is sometimes accompanied by low back pain.
Treatment
Sciatica sometimes resolves without treatment. However, if it doesn't you may be prescribed the following treatments:
painkillers
anti-inflammatory medication
physiotherapy, osteopathy or chiropractic
epidural injections.