Sciatica - Nerve

Terms you should know
Long bones : Bones in the limbs.
Sciatic Nerve : The nerve that serves the legs.
 

Sciatica : Involvement of the sciatic nerve usually marked by pain along the course of the nerve through the buttocks, thigh, and leg.
Sacrum : Sacral spine (lowest part of the back) has seven sacral vertebrae. They are fused together in one piece, which is known as sacrum.
CT scan : A special x-ray procedure using a computer to produce a detailed cross-sectional three-dimensional picture of the bone and discs.
Herniated disc : A disc that is displaced from its position between two vertebrae.
Ligaments : Strong, dense structures made of connective tissue that connects bone to bone across the joint. It stabilizes the joint.
Lumbar : The lower back region.
Magnetic Resonance Imaging (MRI) : Magnetic radio frequency energy used to see internal structures of the body, including bone, discs, and nerves without the use of x-rays.
Nucleus pulposus : Soft center of an intervertebral disc. It is made up of gel-like substance.
Osteophyte : A small, abnormal bony outgrowth.
Prolapsed disc : A disc that bulges out from its position between two vertebrae.
Ruptured disc : A disc with a torn annulus (the tough outer covering of a disc).
Lumbar canal stenosis : Narrowing of the lumbar portion of the spinal canal.
Spondylolisthesis : a condition in which one vertebra slips forward on the one beneath it.

Sciatic is a condion which is caused by damage to the sciatic nerve.
Sciatic nerve is as thick as a finger. It is the largest nerve in the human body. Sciatic nerve fibres begin at the level of fourth and fifth lumbar vertebrae (L4, L5) and the first few segments of the sacrum. It passes through the back of the thigh, into the calf muscles and further downward to the foot. It controls the muscles of the back of the knee and lower leg and provides sensation to the back of the thigh, part of the lower leg and the sole of the foot. In sciatica there is impaired movement and / or sensation in the leg.