Sciatica is pain going down the leg from the lower back. This pain may go down the back, outside, or front of the leg. Onset is often sudden following activities like heavy lifting, though gradual onset may also occur. The pain is often described as shooting. Typically, symptoms are only on one side of the body. Certain causes, however, may result in pain on both sides. Lower back pain is sometimes present. Weakness or numbness may occur in various parts of the affected leg and foot.About 90% of sciatica is due to a spinal disc herniation pressing on one of the lumbar or sacral nerve roots. Spondylolisthesis, spinal stenosis, piriformis syndrome, pelvic tumors, and pregnancy are other possible causes of sciatica. The straight-leg-raising test is often helpful in diagnosis. The test is positive if, when the leg is raised while a person is lying on their back, pain shoots below the knee. In most cases medical imaging is not needed. However, imaging may be obtained if bowel or bladder function is affected, there is significant loss of feeling or weakness, symptoms are long standing, or there is a concern for tumor or infection. Conditions that may present similarly are diseases of the hip and infections such as early shingles (prior to rash formation).Initial treatment typically involves pain medications. However, evidence for pain medication and muscle relaxants is lacking. It is generally recommended that people continue with normal activity to the best of their abilities.
When there is a tear in the anulus fibrosus, the nucleus pulposus may extrude through the tear and press against spinal nerves within the spinal cord, cauda equina, or exiting nerve roots, causing inflammation, numbness, or excruciating pain. Inflammation of spinal tissue can then spread to adjacent facet joints and cause facet syndrome, which is characterized by lower back pain and referred pain in the posterior thigh.Other causes of sciatica secondary to spinal nerve entrapment include the roughening, enlarging, or misalignment (spondylolisthesis) of vertebrae, or disc degeneration that reduces the diameter of the lateral foramen through which nerve roots exit the spine. When sciatica is caused by compression of a dorsal nerve root, it is considered a lumbar radiculopathy or radiculitis when accompanied by an inflammatory response. Sciatica-like pain prominently focused in the buttocks can also be caused by compression of peripheral sections of the sciatic nerve usually from soft tissue tension in the piriformis or related muscles. Diagnosis
Sciatica is typically diagnosed by physical examination, and the history of the symptoms. Physical tests
Generally, if a person reports the typical radiating pain in one leg, as well as one or more neurological indications of nerve root tension or neurological deficit, sciatica can be diagnosed.The most frequently used diagnostic test is the straight leg raise to produce Lasègues sign, which is considered positive if pain in the distribution of the sciatic nerve is reproduced with passive flexion of the straight leg between 30 and 70 degrees.