Neuroglossary
Terms used in brain injury, spinal cord injury and other neurotrauma treatment and rehabilitation
S (sacral spine - system)
sacral spine - Part of the spinal column that contains the sacrum.
sacrococcygeal ligament - The joining of the narrow anterior longitudinal ligament, which broadens as it goes down to the end of the spine, securely uniting with the sacral periosteum and extending on to the pelvic surface of the coccyx.
sacroiliac ligaments - Bands of fibrous tissue that include the anterior, dorsal, interosseous, long posterior and short posterior, and ventral ligaments. The dorsal sacroiliac ligaments are numerous small bands that pass from the tuberosity of the ilium and the posterior inferior and posterior superior iliac spines to the intermediate sacral crest and adjacent areas of the sacrum. The interosseous sacroiliac ligaments are numerous short, strong bundles that connect the tuberosities and adjacent surfaces of the sacrum and the ilium. The ventral sacroiliac ligaments are also numerous thin fibrous bands passing from the ventral margin of the auricular surface of the sacrum to the adjacent portions of the ilium.
sacrospinalis - A large muscular and tendinous mass, found in grooves to the sides of the vertebral column, that changes size at different levels.
sacrum - Wedge-shape bone, positioned like an arrowhead at the end of the arrowﾒs shaft (the spine).
sagittal - Longitudinal plane that divides the body into symmetrical left and right sections. It goes from the center of the nose over the top of the head, following the sagittal suture down over the center of the back. Parasagittal cuts are parallel to that plane. It is perpendicular to the coronal.
sagittalis - Sagittal; general term for a structure situated in the direction of the sagittal suture.
sarcolemma - Delicate plasma membrane that surrounds every striated muscle fiber.
scab - Crust discharged from and covering a healing wound.
scalene muscles - Any of three muscles originating in the cervical spine. On each side of the neck, they bend and rotate the neck and assist breathing by raising of fixing the first two ribs. Also called scalenus.
scapula - Flat, triangular bone in the back of the shoulder; the shoulder blade.
scar - Tough superficial covering made up of dried tissue and/or fibrin; also known as eschar.
scar formation - The appearance of new tissue following coagulation, inflammation, and granulation of a wound.
schizophrenia - A psychotic disorder which, in its active phase, is characterized by characteristic symptoms involving a number of psychological processes. Can be very disabling, even incapacitating.
Schmorl's nodes - Named for Dr. Schmorl, who described a bony defect seem by x-ray of the spine in the upper or lower margin of a vertebral body caused by prolapse of a nucleus pulposus into an adjoining vertebra. Also called intervertebral herniation of the disc.
Schwann membranes (neurolemma)- Thin membranes that spirally enwrap the myelin layers of some myelinated nerve fibers, especially peripheral ones.
sciatic nerve - Largest nerve in the body, a general sensory and motor nerve. It originates in the sacral plexus at L4-S3 and leaves the pelvis through the greater sciatic foramen, and branches by dividing into the tibial and common peroneal nerves, usually in the lower third of the thigh. It distributes through its individual branches
sciatica - Painful condition where pain goes down along the sciatic nerve. It is ordinarily due to a herniated disc in the lumbar region of the spine, radiating to the buttocks and to the back of the thigh, to the leg or foot. Sciatica has been described in medical literature for 3,000 years, but only for sixty years has the herniated disc been attributed as the cause.
sclero- - Combining form meaning hard; denote relationship to the sclera of the eyeball. Also refers to the bone and joints.
sclerotic- Hard or hardening; refers to sclerosis (hardening or overgrowth of fibrous tissue).
sclerotome - Area of the bone or joint or periosteum innervated by a single spinal segment.
scoliosis - Perceptible abnormal lateral deviation in the normally straight vertical line of the spine in the thoracic, lumbar, or thoracolumbar region. Compare with kyphosis and lordosis.
scotoma - A defect in the visual field which is surrounded by a normally functioning field; can be detected by perimetry.
seat-belt injury - See chance-type fracture.
secondary brain damage - Lesions in the brain which arise subsequent to and as a result of primary brain damage and from pathologic processes in other body systems (e.g., cardiac, pulmonary, etc.).
secondary gain - The production or maintaining of bodily or psychological symptoms to satisfy a (largely) unconscious need.
segmental instability - Spinal instability, a condition in which the anatomic elements of the functional spinal unit or its supportive structures are disrupted, so that loads that are normally tolerated result in excessive or abnormal spinal motions, displacements, or strains, causing progressive deformities to develop.
sella - Saddle-shaped depression.
senescence - The process or condition of growing old, especially the state resulting from the changes and accumulations of the harmful effects of the aging process.
sensation - The sensory functions of the nerves sent from the extremities to the brain.
sense fibers - Fibers that carry sensations through the spinal cord to the brain. The cells of the spinal cord receive the sensation, interconnect at that point with the cells that relate with motion, and reaction takes place.
sensory - Impression conveyed by an afferent nerve to the sensorium.
sequestered disc - See free fragment.
sequestration - Type of disc displacement where the extruded segment is fragmented, occasionally with displacement of the free fragment into the spinal canal, often to a site far removed from the point of rupture.
serotonin - Vasoconstrictor that, in humans, is released by the blood platelets and found in high concentrations in many body tissues. It inhibits gastric secretion, stimulates smooth muscle serves as a central neurotransmitter, and is a precursor of melatonin.
sexual development - Refers to the rather abrupt process wherein the reproductive organs mature and the individual attains the sexual characteristics and reproductive capacity typical of the species.
shearing - The tearing or rending of different tissue planes (of the brain) resulting from rotational acceleration and consequent tearing of nerve cell tracts.
sheath - Case or cover such as an enveloping tubular structure like the tissue that encloses a muscle or nerve fiber.
shock - A rapid and substantial drop in blood pressure caused by lowering of effective blood volume.
single proton emission computerized tomography (SPECT) - Specialized form of radionuclide scanning, producing images much like those of a CT scanner, with cross-sectional images (slices).
sinuvertebral nerve - Meningeal branch of spinal nerves: the small branch of each spinal nerve that reenters the intervertebral foramen to supply the dura mater, vertebral column, and associated ligaments. (Ramus meningeus nervorum spinalium.)
-sis - Word termination of Greek origin signifying a state or condition. With a combining vowel it appears as ﾖasis, -esis, -iasis, or -osis.
skeletal traction - Traction applied directly upon the long bones by means of pins Kirschner's wire, etc.
slices - Planes of the body 2 to 5 mm apart that are photographed during CT scans, which use special computer software to concentrate the x-ray on otherwise inaccessible areas of the body.
social/emotional development - Refers to the process wherein the individual members of a species acquire the "rules" which govern social interaction and emotional functioning. From the perspective of ethnology or evolutionary or sociobiology, this social/emotional development proceeds upon a course which more or less parallels sexual and physical development, aimed at creating a state of "conscious" readiness for the evolutionary goal of reproduction and protection of the young for species survival. Because such parallel social/emotional development is REQUIRED in order to render an individual "available" for reproduction, evolutionary and sociobiological theory argues that the normal course of such social emotional development follows a "program" common to the species and is encoded in the individual's DNA.
soft disc - The annulus fibrosus and the nucleus pulposus portion of an intervertebral disc.
soft-tissue injury - In the neck, a syndrome due to damage to the muscles, ligaments, discs, and blood vessels. They are often referred to as whiplash, hyperextension/hyperflexion, acceleration/deceleration injury, cervical strain, or cervical sprain.
soft-tissue window- Used in CT scanning to view discs, the thecal sac, and ligaments.
soma - The body as contrasted to the mind; the body tissue as distinct from the germ cells; the cell body.
somatic - Pertaining to or characteristic of the soma or body; pertaining to the body wall in contrast to the viscera.
somatic nervous system - Those parts of the nervous system concerned with the transmission of impulses to and from those components of the body not included in the three great cavities. That would include the skeletal muscles, bones, joints, ligaments, skin, eye, and ear, etc.
somatic senses - The general senses, such as the senses of touch pressure, heat, cold, pain, and body position.
somato-- Combining form denoting relationship to the body.
somatoform disorders - A group of disorders in which physical symptoms suggesting physical disorder predominate and in which there is strong evidence for a psychologic causation. These disorders include somatization disorder, conversion disorder, psychogenic pain disorder, and hypochondriasis.
somatosensory evoked potential responses - The adequacy of reception of various sensations on the skin surface, can be measured by determining the speed of transmissions of these sensations through the brain stem.
somatosensory evoked potentials (SSEP) - The stimulation of nerves at different points where surface electrode are placed and recordings made, to find out the proximal sensory conduction in (mainly) proprioceptive fibers, including spinal nerve root, tracts in the spinal cord, and brain stem.
somite - One of the paired blocklike masses of mesoderm, arranged segmentally alongside the neural tube of the embryo, forming the vertebral column and segmental musculature; called also mesoblastic or mesodermal segment.
sonography - Test where images are formed from echoes of the sound waves.
sperma-, spermato- - Combining form denoting relationship to seed, specifically to the male generative element.
spermatogenesis - The process of formation of spermatozoa, including spermatocytogensis and spermiogenesis.
spermatozoid cells - Generated by the testes; a single sperm cell fuses with an ova to create pregnancy.
spheno- - Combining form showing relationship to the sphenoid bone or to a wedge or meaning wedge-shaped.
sphenoid - Wedge-shaped; designating, especially, a very irregular wedge-shaped bone at the base of the skull.
sphenoid bone - Single, irregular, wedge-shaped bone at the base of the skull that forms a part of the floor of the anterior, middle, and posterior cranial fossae.
spina bifida - Describes a wide range of developmental defects of the vertebral column; commonly called cleft spine.
spina bifida cystica - More serious congential malformation, in which the meninges and/or spinal cord herniated through the defect in the vertebral arch.
spina bifida with meningocele - Condition where the meninges alone are herniated.
spina bifida with meningomyelocele - Condition where the meninges and spinal cord and/or nerve roots herniated. Frequently, patients have spinal cord and/or spinal nerve root malfunction such as paralysis of the limbs and incontinence of urine and feces.
spina bifida occulta - Simplest form of spina bifida; in it, the two sides of the neural arch (laminae of the vertebral arch) of one or more vertebrae fail to develop fully and fuse during embryonic development. Diagnosed by x-ray.
spinal accessory nerve - Cranial Nerve XI. Largely motor, this nerve supplies sternomastod and trapezius muscles.
spinal block - Lumbar puncture where a local anesthetic agent is injected directly into the cerebral spinal fluid. Usually, within one minute, the nerve roots are affected, as compared to ten to twenty minutes for an epidural block. A spinal block uses only about 10% as much anesthetic agent as needed for the epidural block, since the anesthetic does not have to diffuse through the meninges to reach the CSF. The nerve roots in the dural sac are blocked by spinal anesthesia, and control of the amount of anesthetic injected and the positioning of the patient relates to the number of spinal cord segmental levels being blocked. So that the anesthetic agent will flow in the right direction and not toward the head, affecting the nerves controlling vital functions (respiration, etc.) the patientﾒs head should be higher than the feet. (See epidural block)
spinal canal - Vertebral canal. A relatively narrow tubular passage or channel in the spine, encasing the spinal cord and the nerves. It changes in size at different levels, and its diameter can be measured very well with axial views of the CT scan.
spinal compression- Condition where pressure is exerted on the spinal cord, as by a tumor, spinal fracture, etc.
spinal cord - Part of the central nervous system that extends caudally from the foramen magnum down the spine; it has thirty-one pairs of nerves and connects the brain with the rest of the body.
spinal instability - When the anatomic elements of the functional spinal units, composed of the motion segment (two adjacent vertebral bodies, the intervening disc, the facet joints, and connecting ligamentous structures) and its supportive structures are disrupted, the result is spinal instability. This makes loads that are normally tolerated result in excessive or abnormal spinal motions, displacements, or strains, bringing about the development of progressive deformities.
spinal nerves - Sensory and motor nerves which connect the spinal cord to the periphery of the body.
spinal segmental unit - Complex of two vertebrae, between which is a disc. The disc lies in front of the segmental unit. The facets are on the arches in back and toward the sides. These three places are the only areas of movement in the spine.
spinal tap - Lumbar puncture.
spinous processes - Posterior parts of the vertebrae that result from the fusion of the laminae. They are felt like knuckles in the midline of the back.
splenius capitis - Deep back muscles that control the veretebral column, acting in concert with many other muscles. The splenius capitis and splenius cervicis, working together, retract the head. Singly, they turn it to the side, working with the sternocleidomastoid muscle.
splenius cervicis - Deep back muscles that control the vertebral column, acting in concert with many other muscles. The splenius capitis and splenius cervicis, working together, retract the head. Singly, they turn it to the side, working with the sternocleidomastoid muscle.
spondyl-, spondylo- - Combining form meaning vertebra. A general term that designates a specific type of bony structure.
spondylarthritis - Arthritis of the spine.
spondylitis - Inflammation of the veretebrae.
spondylodesis - Vertebral or spinal column fusion.
spondylogenic - Originating in the spine.
spondyloisthesis - Forward displacement or slip of one vertebral body over an adjacent vertebral body, ordinarily of the fifth lumbar over the body of the sacrum, or of the fourth lumbar over the fifth, usually due to a developmental defect in the pars interarticularis. Spondylolytic spondylolisthesis is one of six different categories of this entity; the other ones include dysplastic, degenerative, traumatic, pathologic, and iatrogenic spondylolistheses.
spondylolysis - Dissolution of a vertebra; a condition marked by a defect in the vertebral arch, and refers to a cleft or separation of the pars interarticularis that divides the neural arch into two segments. The diagnosis is made by x-ray.
spondylosis - Degenerative condition that involves two facet joints and an intervertebral disc in the lumbar spine, caused by osteoarthritis. It can be started by the failure of the disc. As the disc volume decreases, the facets become involved, and abnormal motion comes into play. When an osteophyte forms, the condition is then called spondylosis.
spondylosis deformans - Changes in the spine, in which bone production such as osteophytes have resulted from anterior displacement of the intervertebral disc.
sprain - Joint injury in which some of the fibers of a supporting ligament are ruptured, but the continuity of the ligament remains intact.
Spurlingﾒs test - The doctor presses the top of the patientﾒs head down, gradually, to determine the location of the pain and numbness.
stability - The quality of maintaining a constant character in the presence of forces that threaten to disturb it.
static - At rest; in equilibrium; not in motion. Not dynamic.
statis - Stoppage or diminution of the flow of blood or other body fluid in any part; a state of equilibrium among opposing forces.
stenosis - Narrowing; pathological compression within the spinal canal. This abnormal narrowing impedes the flow of contrast medium during imaging and has been defined as narrowing of the spinal canal, including the lateral recesses, and the intervertebral foramina due to encroachment on the neural and vascular structures by the surrounding bone and soft tissues. It can stem from a congenital defect or be acquired from tumors, osteophytes, discs, hypertrophy of the facets and ligaments, hematomas, fractures, or other causes.
stereognosis - Ability to perceive and understand the form and nature of objects by touching them.
sternocleidomastoid muscle - Large, thick muscle that passes obliquely across the side of the neck, being enclosed between the two layers of the deep cervical fascia. It is thick and narrow at its central part but is broader and thinner at each extremity. It arises by two heads from the sternum and clavicle. These two portions are separated from one another, at their origin, by a triangular cellular interval, but become gradually blended, below the middle of the neck, into a thick, rounded muscle, which is inserted, by a strong tendon, into the outer surface of the mastoid process.
sternohyoid muscle - Thin, narrow, and ribbonlike muscle that arises from the inner extremity of the clavicle, the posterior sterno-claviular ligament, and the upper and posterior part of the first piece of the sternum. It passes upward and inward, and is inserted by short tendinous fibers into the lower border of the body of the os hyoids. This muscle is separated, below, from the same by a considerable interval, but the two muscles come into contact with one another in the middle of their course, and from this upward, they lie side by side.
sternum - Long, flat bone situated along the frontal midline of the chest, joining with the ribs on each side and with the collarbone above.
strabismus - Weakness of eye muscles allowing eyes to cross.
straight leg raising test - Test in which the patient lies flat on the bed. The doctor keeps the leg straight, puts one hand over the patella and the other one under the heel, and elevates the leg away fro the bed. The test is positive if the patient complains of leg pain and not backache when angled to some degree between 20 degrees and about 80 degrees. The test has more value when it is a small angle, such as 20 to 30 degrees, and has even more significance if the other variations, Lasegue and bow string signs, are positive.
strain - Overstretching or overexertion of some part of the musculature.
striated muscle - Muscle responsible for the skeletonﾒs movement (and the movement of organs such as the orb of the eye and the tongue). Also called voluntary muscle and skeletal muscle.
stroma - Supporting tissue or matrix of an organ, as distinguished from its functional element, or parenchyma.
stupor - A substantially lowered level of consciousness wherein arousal is difficult; mental and physical activity are minimal.
sub- - Prefix signifying under, near, almost, or moderately.
subannular - Anatomic position deep in the outer fibers of the annulus fibrosus.
subarachnoid space - Space between the arachnoid and pia mater that contains cerebrospinal fluid (CSF) and the vessels of the spinal cord. This space in the spinal region is narrow, except here it is below the conus medullaris. It is largest in the lower part of the vertebral canal, where the CSF surrounds the nerve roots comprising the cauda equina. Within the dural sac, fro L2 to S1, it is known as the lumbar cistern and besides the CSF, it contains the cauda equina and filum terminale.
subdural hemorrhage - Results from venous bleeding between the dura and arachnoid; its presence is generally indicative of a severe head injury.
subdural hygroma - An excessive collection of cerebrospinal fluid (CSF) in the subdural space.
subdural space - Potential space between the dura and the arachnoid that contains only a capillary layer of fluid.
subligamentous - Anatomic position beneath the posterior longitudinal ligament.
subluxation - Incomplete or partial dislocation, such as when one vertebra slides beneath another.
submental - Situated beneath the chin.
substance - Peptide composed of eleven amino acids, present in the intestine, where it serves to contract the intestine and dilate blood vessels. It is also present in a number of neuronal pathways in the brain and in primary sensory fibers of peripheral nerves and has been suggested to be a neurotransmitter associated with transmission of pain impulses.
super- - Prefix showing that something is exceptional or above the average.
superior - Relative directional term meaning toward the head, situated above, or facing above. It is the opposite of inferior.
superior gluteal nerve - Motor and general sensory nerve that originates in the sacral plexus, L4-S1. It distributes to the gluteus medium and minimus muscles, tensor fasciae latea, and hip joint.
supraspinous ligament - A single long, vertical, fibrous band, passing over and attached to the tips of the spinous processes of the vertebrae from the seventh cervical to the sacrum. It is continuous above with the ligamentum nuchae.
surgical fixation - The act or operation of holding, suturing, or fastening in a fixed position. The fastening internally of the ends of a fractured bone by means of wires, plates, screws, or nails applied directly to the fractured bone. The open reduction and stabilization of fractured bony parts by direct fixation to one another with surgical wires, screws, pins, and/or plates.
suture - Fibrous joint in which the opposed surfaces are closely united, as found in the skull. They allow flexibility in fetuses for growth and passage through the birth canal and for young children, for growth of the brain. In adults, bone has replaced the fibrous tissue, with a fusion allowing complete protection for the brain from external factors.
swelling (edema) - Enlargement of the working space in the bodyﾒs place of injury that takes place within the interspaces of the tissue during the process of inflammation.
sympathetic ganglion - Aggregation of cell bodies of primarily adrenergic neurons of the sympathetic nervous system. These ganglis are arranged in chainlike fashion on either side of the spinal cord.
sympathetic nervous system - Thorocolumbar portion of the autonomic nervous system. The system plays a role in the excitation and relaxation of muscle and provides an important additional surface for the exchange of metabolites between muscle and the extracellular space.
sympathetic phenomena - Sweating, discoloration of the skin, shiny skin, or changes in temperature; also called autonomic phenomena.
symphysis - When originally separate bones grow together. For example, the two pubic bones of the two halves of the lower jawbone. It also refers to the line or the place where they are joined. It can be called a symphysis whee bones are joined together by cartilage without a joint cavity lining or a cartilaginous joint two bony surfaces covered with thin layers of hyaline cartilage, cushioned by flattened plates or discs of fibrocartilage. They usually have slight movement called amphiarthroses. A good example is the intervertebral joints between the bodies of vertebrae. Also called secondary synchondrosis.
syn- - Prefix signifying union or association.
synapse - The connection between the end of a nerve and the adjacent structure, such as a muscle cell or another nerve ending. Various transmitter chemicals liberated into the synapse make nerve transmissions possible.
synarthrosis - Joint, classified as to degree of movement, as an immovable joint See amphiarthrosis and diarthrosis.
synchondrosis - Usually temporary, this type of cartilaginous joint ordinarily converts into bone before adult life. It allows growth, not movement.
syncytiotrophoblast - Outermost cyncytium layers of the trophoblast. This mass of protoplasm results from the merging of cells.
syndesmophytes - Bony excrescence or outgrowth from a ligament.
syndesmosis - Fibrous joint in which bones are held closely together, but not touching, by collagenous fibers or interosseous ligaments. They are generally synarthroses (immovable joints), although, if thee is a small amount of movement, it is related to the distance between the bones as well as the flexibility of the fibrous connecting tissue. This limited movement adds strength to the joint.
syndrome - Complex of symptoms occurring together. In morbid states, a syndrome is the sum of signs of any diseased state.
synostosis - When adjacent bones join together, having normally been separate bones. This includes parts of a single bone formed by osseous material (ossified connective cartilage or fibrous tissue). Compare with ankylosis.
synovial - Pertaining to or secreting a transparent alkaline viscid fluid, resembling the white of an egg.
synovial cavity - Space between two articulating bones; also called joint cavity.
synovial fluid - The fluid surrounding synovial joints that makes them slippery and smooth.
synovial joint - Classified as to structure, it has a joint cavity, with the ends of the bones covered by a smooth hyaline articular cartilage; the joint is lubricated and nourished by thick synovial fluid. It is enclosed by a flexible articular capsule. Most permanent joints I the body are synovial, and of all the types of joints, these allow the greatest range of movement (diarthroses), due to their special form of articulation.
synovial membrane - Membrane lining the cavity of joints and similar areas where friction needs to be reduced; composed of loose connective and adipose tissues covered by fibrous and connective tissue.
synovium - The specialized connective tissue layer that lines the inside of the synovial capsule and varies in thickness and density.
synthesis - The artificial building up of a chemical compound, by the union of its elements or from other suitable starting materials.
system - Group of organs that work together to perform a major body function.
