Instruments which are powered by compressed air or electricity and are used in surgical procedures to cut, drill, or otherwise remove bone and cartilage, as well as to evacuate fluids.

Tests occurring prior to clinical studies, usually in vitro or in vivo involving animals. The purpose of these studies is to determine the safety and efficacy of the test material.

A regulatory method for gaining a marketing clearance from the FDA for a Class III medical device. A company submits information to the FDA that documents the safety and effectiveness of the device.

A regulatory method for gaining clearance from the FDA to market a device. The FDA is petitioned by a company to determine if a particular medical device is "substantially equivalent" to a device which was commercially available prior to May 28, 1976. This method usually applies to Class I or II medical devices.

An artificial body part such as an artificial leg or arm. The term prosthesis is also used to describe some of the implants used in the body such as a hip or knee replacement device.

Nearest the center of the body.

A form of non-union in which there is the formation of a false joint with some cartilage covering the ends of the bones and a cavity containing fluid that resembles a normal joint.

Paralysis of all four limbs.

A physician who specializes in the use of radiant substances, such as x-rays and radioactive isotopes to diagnose and treat diseases.

The surgical removal of part of a structure, such as bone.

The removal of bone tissue by normal physiological process or as part of a pathological process such as an infection.

In spinal applications, a slender, metal implant which is used to immobilize and alien the spine.

See Herniated Disc.

A part of the spine that is also part of the pelvis. It articulates with the ilia at the sacroiliac joints and articulates with the lumbar spine at the lumbosacral joint. The sacrum consists of five fused vertebrae that have no intervertebral discs.

Longitudinal.

A lay term indicating pain alone the course of a sciatic nerve, especially noted in the back of the thigh and below the knee.

Lateral (sideways) curvature of the spine.

A state of infection of tissue due to disease-producing bacteria or toxins.

The rigid framework of bones that gives form to the body, protects and supports the soft organs and tissues, and provides attachments for muscles.

The bony channel that is formed by the intravertebral foramen of the vertebrae and in which contains the spinal cord and nerve roots.

See Spine.

The longitudinal cord of nerve tissue that is enclosed in the spinal canal. It serves not only as a pathway for nervous impulses to and from the brain, but as a center for carrying out and coordinating many reflex actions independently of the brain.

See Disc (Intervertebral).

A surgical procedure to permanently join bone by interconnecting two or more vertebrae in order to prevent motion (see Arthrodesis).

Reduction in the diameter of the spinal canal due to new bone formation which may result in pressure on the spinal cord or nerve roots.

The flexible bone column extending from the base of the skull to the tailbone. It is made up of 33 bones, known as vertebrae. The first 24 vertebrae are separated by discs known as intervertebral discs, and bound together by ligaments and muscles. Five vertebrae are fused together to form the sacrum and 4 vertebrae are fused together to form the coccyx. The spine is also referred to as the vertebral column, spinal column, or backbone.

The portion of the vertebrae that protrudes posteriorly from the spinal column. The spinous processes create the "bumps" felt on the midline of the back.

Inflammation of vertebrae.

A defect in the construct of bone between the superior and inferior facets with varying degrees of displacement so the vertebra with the defect and the spine above that vertebra are displaced forward in relationship to the vertebrae below, It Is usually due to a developmental defect or the result of a fracture.

Displacement of one vertebrae over another with fracture of a posterior portion of the vertebra. A defect in the neural arch between the superior and inferior facets of vertebrae without separation at the defect and therefore no displacement of the vertebrae. It may be unilateral or bilateral and is usually due to a developmental defect but may be secondary to a fracture.