Glossary

Aging disc - Disc demonstrating the features of normal aging. Spondylosis deformans possibly represents the normal aging process.

Allograft Bone - Sterile bone derived from another human which is used for grafting procedures.

Annulus (abbreviated form of annulus fibrosus) - A multilaminated ligament surrounding the periphery of each disc space, attaching, craniad and caudad, to end-plate cartilage and ring apophyseal bone and blending centrally with nucleus pulposus

Annulus Fibrosus - The outer, fibrous, ring-like portion of an intervertebral disc.

Anterior - The front portion of the body. It is often used to indicate the position of one structure relative to another.

Anterior displacement - Displacement of disc tissues beyond the disc space into the anterior zone.

Anterior zone - Peridiscal zone that is anterior to the mid-coronal plane of the vertebral body.

Anterolateral - Situated or occurring in front of and to the side.

Apical Vertebra - The most rotated vertebra in a curve; the most deviated vertebra from the patient's vertical axis.

Arthritis - Inflammation of a joint usually characterized by swelling, pain, and restriction of motion.

Arthrodesis - The fusion of bones across a joint space, thereby limiting or eliminating movement. It may occur spontaneously or as a result of a surgical procedure, such as fusion of the spine.

Arthropathy - Any disease or disorder involving a joint.

Arthroplasty - The surgical remodeling of a diseased or damaged joint.

Arthroscope - An instrument inserted into a joint cavity to view the interior of a joint and correct certain abnormalities. An arthroscope is an endoscope for use in a joint.

Arthroscopy - The procedure of visualizing the inside of a joint by means of an arthroscope.

Articular - Pertaining to a joint.

Asymmetric bulge - Presence of outer anulus beyond the plane of the disc space, more evident in one section of the periphery of the disc than another, but not sufficiently focal to be characterized as a protrusion. Note: Asymmetric bulge is a morphologic observation of various potential causes and is not a diagnosis. See: bulge.

Autogenous Bone - Bone originating from the same individual; i.e. an individual's own bone.

Autograft Bone - Bone transplanted from one part to another part of the body in the same individual.