The schemas are a set of 'types', each associated with a set of properties. The types are arranged in a hierarchy.he schemas are a set of 'types', each associated with a set of properties. The types are arranged in a hierarchy.
Inadequate stretching and warming up prior to exercise, or advancing your exercise program too quickly, or beginning a new exercise program, have all been known to cause symptoms. In some people, just vigorous walking or exercising on uneven ground is enough to exacerbate a flare-up of sciatica nerve pain.
Sciatica is caused by inflammation or compression of the sciatic nerve or nerve roots in the lower spine. It may also be caused by damage to nerve roots. Sciatica is not a disease in itself and its causes are various. A pinched nerve in the lower spine causes sciatica. The most common cause of sciatica is a herniated disc in the lumbar spine (lower back) that puts pressure on the sciatic nerve or a nerve root. A herniated disc can occur suddenly and cause acute pain or it may develop gradually.