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DE ANDRADE and MACNAB – Anterior approach for cervical occipital fusion.
DECOMPRESSION – In relation to the spine this procedure is carried out to relieve pressure on the spinal cord or nerve roots.
DECOMPRESSIVE LAMINECTOMY – A decompression done by removing the lamina and spinous process.
DEEP BRAIN STIMULATION -A tremor control therapy for patients with Parkinson’s Disease or essential tremors, who do not respond effectively to medications. It is a surgical reversible procedure that involves implanting a device to deliver mild electrical stimulation to block the brain signals that tremor.
DEGENERATIVE – The lesion results from intersegmental instability of long duration.
DEGENERATIVE DISC DISEASE – Gradual or rapid deterioration of the chemical composition and physical properties of the disc space.
DEGENERATIVE TENOSIS – Gradual hypertrophy of the vertebral body margin, facet joints, and ligamentum flavum leading to stenosis.
DE-MINERALIZED BONE – Bone tissue which has been depleted of its minerals; e.g., calcium and phosphorous.
DEMINERALIZED BONE MATRIX (DMB) – is a source of BMP and is derived from pulverized bone specimens that are demineralized with an acid solution. It is used as a bone grafting material, but DMB has produced disappointing results in clinical studies, probably due to low concentrations of BMP that can also vary from batch to batch.
DENDRITE – A nerve cell process that transmits impulses toward the cell body.
DEPRESSED SKULL FRACTURE – A break in the bones of the head in which some bone is pushed inward, possibly pushing on or cutting into the brain.
DERMATOME – Refers to the distribution of sensory nerves near the skin that are responsible for pain, tingling, and other sensations (or lack of).
DIABETES INSIPIDUS – Excretion of large amounts of urine of low specific gravity. The inability to concentrate urine.
DIAPHRAGM – The muscle between the abdomen and thorax; main muscle of normal breathing.
DIASTEMATOMYELIA – Congenital defect associated with spina bifida in which the spinal cord is split in half by bony spicules or fibrous bands, each half being surrounded by a dural sac.
DIFFUSE AXONAL INJURY – Damage to the axons of many nerve cells that lie in different parts of the brain.
DIFFUSE BRAIN INJURY – Damage to the brain that can affect many parts of the brain, often in a subtle fashion; examples include diffuse axonal injury and inadequate blood flow.
DIPHENYLHYDANTOIN – Dilantin; a medication used to control seizures.
DIPLOPIA – Double vision, due usually to weakness or paralysis of one or more of the extra-ocular muscles.
DISC – The intervertebral disc – cartilaginous cushion found between the vertebrae of the spinal column. It may bulge beyond the vertebral body and compress the nearby nerve root, causing pain. The terms “slipped disc”, “ruptured disc” and “herniated disc” are often used interchangeably even though there are subtle differences.
DISC DEGENERATION – The loss of the structural and functional integrity of the disc.
DISCECTOMY – Surgical removal of part or all of an intervertebral disc material placing pressure on neural elements.
DISCITIS – Nonbacterial inflammation of an intervertebral disc or disc space.
DISC SPACE INFECTION – Infection in the space normally occupied by an intervertebral disc.
DISKOGRAM – The graphic record, usually radiographic, of diskography.
DISKOGRAPHY – Radiographic demonstration of intervertebral disc by injection of contrast media into the nucleus of the pulposus.
DISLOCATION – Displacement of an organ or any part; specifically disturbance or disarrangement of the normal relation of the bones entering the formation of a joint.
DISTAL – Situated away from the center of the body.
DOME – The round balloon like portion of the aneurysm which usually arises from the artery from a smaller portion called the neck of the aneurysm.
DOPPLER – A non-invasive study which uses sound waves to show the flow in a blood vessel and can be used to determine the degree of narrowing (percent stenosis) of the vessel. A wand is placed on the skin over the vessel to be imaged. This study has no risks and is not painful.
DORSAL COLUMN – The main, normal sensory tract to the brain.
DORSAL LATERAL COLUMN – The main tract of position and tone to the brain.
DORSOLATERAL – An approach to the dorsal spine by costotransversectomy, usually done for fractures and other affections of the spinal cord.
DOUBLE CURVE – Two lateral curves in a single spine; double major curve is two lateral curves of equal magnitude, and double thoracic curve is two thoracic curves.
DUNN – For myelomeningocele spinal deformity; use of contouring L-rod for posterior stabilization.
DURA – Dura mater.
DURAL – Pertaining to the dura.
DURA MATER – A tough fibrous membrane which covers the brain and spinal cord, but is separated from them by a small space.
DWYER – Anteriorly placed screws and band device for correction of spinal deformities.
DWYER-HARTSILL – For failed lumbar degenerative disc disease; pedicle screws wired to a rectangular frame along with posterolateral fusion.
DYSESTHESIA – A condition in which a disagreeable sensation is produced by ordinary touch, temperature or movement.
DYSPHASIA – Difficulty in the use of language due to a brain lesion without mental impairment.
DYSPLASTIC – Congenital abnormalities of the arch of the sacrum or the arch of L-5 that permit the slipping to occur.
DYSRAPHISM – Any failure of closure of the primary neural tube. This general category would include the disorder myelomeningocele.
DYSTONIA MUSCULORM DEFORMANS – An affliction occurring especially in children, marked by muscular contractions producing distortions of the spin and hips.