الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Sciatica has been described as the pain in hip and lower extremities affecting the sciatic nerve and its branches along the discogenic and non-discogenic causes and developed after secondary pathologies.The sciatic nerve is the broadest nerve in the body and is the continuation of the upper band of the sacral plexus. It leaves the pelvis via the greater sciatic foramen below the piriformis and descends between the greater trochanter and ischial tuberosity, along the back of the thigh, dividing into the tibial and common peroneal nerves, proximal to the knee.Pathological changes in the sciatic nerve are mainly due to localized interference of microvascular function and structural changes in the sciatic nerve or adjacent tissues.When tissues are subjected to load or pressure, they deform and pressure gradients are formed, redistributing the compressed tissue toward areas of lower pressure. Nerve compression usually occurs at sites where the nerve passes through a tight tunnel formed by stiff tissue boundaries. The resultant confined space limits movement of tissue and can lead to sustained tissue pressure gradients.The most common cause of sciatica in about 90% of patients is spinal disc herniation pressing on one of the lumbar or sacral nerve roots. Other problems that may result in sciatica include spondylolisthesis, spinal stenosis, piriformis syndrome, pelvic tumors, and compression by a baby’s head during pregnancy.