Sciatica is not in itself a medical condition but rather a symptom of various kinds of back ailment. It is the travelling of pain down the sciatic nerve which starts at the buttocks and runs down the side of each leg.
It can manifest itself at different levels of intensity ranging from numbness to constant pain travelling down a leg. It usually goes down one leg, not both.
It often feels like a numbness or tingling.
It is often worse when sitting and sometimes there is a sharp pain that it makes it difficult to stand up and walk.
Herniated discs, Spinal Stenosis and degenerative disease are some of the ailments that can lead to sciatica. Whatever the triggering cause, the effect is that at some point the nerve is being compressed. The point at which they are compressed affects where in the leg, the pain or numbness will be felt.
There are two situations when Sciatica can require urgent medical attention. The first is when there are bowel or bladder incontinences or a progressive numbness of the legs. These can happen when there is extreme compression of the nerve sac in the lower spine.
The other is when the nerve is actually damaged. Weakness and numbness in the leg can be a possible indication of this.