Glossary
- ARACHNOID
- Middle layer of membranes covering the brain and spinal cord.
- ARACHNOIDITIS
- Inflammation of the arachnoid membrane, most commonly seen within the spinal cord around the spinal cord and cauda equina.
- ARNOLD-CHIARI MALFORMATION
- A condition in which there is displacement of the medulla and cerebellum into the opening in the basilar part of the occipital bone. It is one of the causes of hydrocephalus and is usually accompanied by spina bifida and menigomyelocele.
- ARTERIOGRAPHY
- See angiography.
- ARTERIOSCLEROSIS
- Thickening and calcification of the arterial wall with loss of elasticity and contractility.
- ARTERIOVENOUS
- Relating to both arteries and veins.
- ARTERIOVENOUS MALFORMATION
- Collection of blood vessels with one or several abnormal communications between arteries and veins which may cause hemorrhage or seizures.
- ARTERY of ADAMKIEWICZ
- An important source of blood supply to the lower portion of the spine, usually occurring at T-9 to T-11 level; however, not the only blood supply to the cord at that level.
- ARTHRALGIA
- Joint pain.
- 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 it's 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.
- ASTROCYTE
- Cell which supports the nerve cells (neurons) of the brain and spinal cord.
- ASTROCYTOMA
- Tumor within the substance of the brain or spinal cord made up of astrocytes - often classified from Grade I (slow-growing) to Grade III (rapid-growing).
- ATAXIA
- A loss of muscular coordination, abnormal clumsiness.
- ATHETOSIS
- A condition in which there is a succession of slow, writhing, involuntary movements of the fingers and hands, and sometimes of the toes and feet.
- ATLANTO-AXIAL
- Pertaining to the atlas and the axis; denoting the joint between the first two cervical vertebrae.
- ATLANTO-EPISTRPHIC
- See atlanto-axial.
- ATLANTO-OCCIPITAL
- Relating to the atlas and the occipital bone.
- ATLANTO-ODONTOID
- Relating to the atlas and the dens of the axis.
- ATLAS
- First cervical vertebrae, articulating with the occipital bone and rotating around the dens of the axis.
- ATONIC SEIZURE
- Seizures that are characterized by a sudden loss of muscle tone, causing the individual to instantly drop to the floor, commonly known as drop attacks.
- ATROPHY
- A wasting of the tissues of a body part.
- AURA
- Warning sign that people with epilepsy often experience prior to the onset of a seizure, which may consist of a strange taste, bad feeling, or tingling sensation.
- 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.
