pain along the course of the sciatic nerve, which runs from the lower back down the legs. The pain often develops following an unusual movement or exertion that places a strain on the lumbar portion of the spine, where the nerve has its roots, either immediately or after an interval of several hours to a few days. The pain may become more severe with coughing, sneezing, and flexion of the neck. It is relieved by positions that minimize traction on the sciatic nerve; for this reason, a person with sciatica tends to walk with the affected leg bent at the knee and externally rotated at the hip. (see also Index: vertebra)

Sciatica is commonly associated with the rupture of a portion of an intervertebral disk into the spinal canal. Most cases, including those in which the nerve is displaced by protruding disk substance, can be treated effectively by bed rest on a firm mattress for several days to a few weeks. In some instances, however, surgical decompression of the nerve is necessary in order to prevent repeated attacks of disabling pain or to relieve serious, progressive disturbances in function of the sciatic nerve, which take the form of weakness and sensory loss in the leg.

Sciatica usually is a benign, if temporarily disabling, reflection of human structural imperfection. It may also, however, develop as a symptom of some local compressive lesion other than a protruded intervertebral disk; or it may indicate a more generalized disorder involving the peripheral nerves.

 

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