Situated outside the thin, tough dural membrane that surrounds the brain and spinal cord.

Removal by cutting away material.

A posterior structure of a vertebra which articulates with a facet of an adjacent vertebra to form a facet joint that allows motion in the spinal column. Each vertebra has two superior and two inferior facets.

Excision of a facet.

A fracture that occurs in bone or in other materials. Including metal, as a result of repeated stress as opposed to a single injury.

The replacement of normal tissue with scar tissue.

"Soft spots" of the infant's head, normal unossified areas in the infant skull.

The Federal government agency that has regulatory authority over the manufacture, distribution, and labeling of drugs, medical devices, and foods.

A natural opening or passage in bone.

Surgical opening or enlargement of the bony opening transversed by a nerve root as it leaves the spinal cord.

A disruption of the normal continuity of bone.

Surgery intended to improve the function of the central nervous system. Astereotactic head frame is used along with imaging techniques to map the brain and localize the surgical target.

Union or healing of bone (see Arthrodesis).

Discharge of milk from the breasts.

Equipment that delivers a precise concentrated dose of radiation to a predetermined target using gamma rays.

Seizures involving widespread a reason both sides of the brain at the time of onset. The generalized nature of these seizures accounts for their dramatic manifestations, which include loss of consciousness or awareness and convulsions. About 39% epileptics suffer primarily from generalized seizures.

Most widely used system of classifying the severity of head injuries or other neurologic diseases.

The major support cells of the brain, involved in the nutrition and maintenance of nerve cells.

Extrusion of part of the nucleus pulposus material through a defect in the annulus fibrosus.

The occurrence of bone growth in an abnormal location.

For spinal applications, a metallic medical device used to connect spinal structures to a rod.

The lattice-like structure of bone composed of calcium and phosphorous crystals which deposits on collagen to provide the rigid structure of bone.

A part of the pelvic bone that is above the hip joint and from which autogenous bone grafts are frequently obtained.

The large, prominent portion of the pelvic bone at the belt line of the body.

Limitation of motion or fixation of a body part usually to promote healing.

Describing biological phenomena that are made to occur outside the living body traditionally in a test tube). In vitro is Latin for in glass.

Within a living body. In vivo is Latin for in life.

Situated below or directed downward.

Consent of the patient who has received sufficient information to have surgery, receive medication, or participate in a clinical study.

A committee designated by an institution, Such as a hospital, to review and approve research projects; e.g., clinical studies in that institution.