TERMINOLOGY USED IN FASCIA RESEARCH

actin is a common protein found in many eukaryotic cell types. It polymerizes forming microfilaments that have an array of functions including regulating contractility, motility, cytokinesis, phagocytosis, adhesion, cell morphology, and providing structural support.

adherens junctions are a type of intercellular junction that links cell membranes and cytoskeletal elements within and between cells, connecting adjacent cells mechanically.

adhesions are bands of scar-like tissue that form between two surfaces inside the body.

adhesive capsulitis is an inflammatory condition that restricts motion in the shoulder, commonly referred to as “frozen shoulder”.

alpha-1-antitrypsin is a glycoprotein, generally known as serum trypsin inhibitor that inhibits a wide variety of proteases. It protects tissues from enzymes of inflammatory cells, especially elastase, and the concentration can rise upon acute inflammation. In its absence, elastase is free to break down elastin.

alpha smooth muscle actin is an isoform typical of smooth muscle cells and one of six known types of actin. In addition to its presence in organ tissue, alpha smooth muscle actin has been identified in myofibroblasts, where it plays an important role in focal adhesion maturation and in inhibition of cell motility.

angiogenesis refers to a physiological process involving the growth of new blood vessels from pre-existing vessels as in the process of wound healing.

aponeurosis is a thin, flat tendon-like expansion of fascia important in the attachment of muscles to bones, other muscles, and in forming sheaths around muscles.

aponeurotomy is a surgical cutting of an aponeurosis.

apoptosis is a morphologic pattern of cell death affecting single cells, marked by shrinkage of the cell, condensation of chromatin, formation of cytoplasmic blebs, and fragmentation of the cell into membrane-bound apoptotic bodies that are eliminated by phagocytosis. It is a mechanism for cell deletion in the regulation of cell populations.

astrocytes are a neuroglial cell of ectodermal origin, characterized by fibrous, protoplasmic, or plasmatofibrous processes. Collectively, such cells are called astroglia.

basement membrane is  a sheet of amorphous extracellular material upon which the basal surfaces of epithelial cells rest; other cells associated with basement membranes are muscle cells, Schwann cells, fat cells, and capillaries. The membrane is interposed between the cellular elements and the underlying connective tissue. It comprises two layers, the basal lamina and the reticular lamina, and is composed of Type IV collagen (which is unique to basement membranes), laminin, fibronectin, and heparan sulfate proteoglycans.

basil lamina is the layer of the basement membrane lying next to the basal surface of the adjoining cell layer, composed of an electron-dense lamina densa and an electron-lucent lamina lucida.

benign joint hypermobility syndrome is an alternate name for Ehlers-Danlos syndrome, type III, inherited as an autosomal dominant trait and characterized by hypermobility of the joints with minimal abnormalities of the skin.

blepharospasm is a chronic, unremitting, bilateral, variably progressive dysfunction of the nerve that controls the muscles around the eye. It manifests itself as an uncontrollable, forcible closure of the eyelids. It often affects both eyes at once, but it can also affect only one eye. Severe blepharospasm can cause the eyelids to be forcibly closed for a duration longer than the typical blink reflex, causing a variable interruption in the ability to see. This term is also used by some to describe an idiopathic eye twitch.

bradykinin is a nonapeptide produced by activation of the kinin system in a variety of nflammatory conditions. It is a potent vasodilator and also increases vascular permeability, stimulates pain receptors, and causes contraction of a variety of extravascular smooth muscles.

bruxism is an involuntary, nonfunctional, rhythmic or spasmodic gnashing, grinding, and clenching of teeth (not including chewing movements of the mandible), usually during sleep, sometimes leading to occlusal trauma.

calcitonin gene-related peptide is a 37–amino acid polypeptide encoded by the calcitonin gene that acts as a potent vasodilator and neurotransmitter. It is widely distributed in the central and peripheral nervous systems and is also present in the adrenal medulla and gastrointestinal tract.

caldesmon is a protein that exists in two isoforms: a high molecular weight form found in smooth muscles that can bind to actin and tropomyosin, prevent actin-myosin linkage, and inhibit muscle contraction; and a low molecular weight form found in non-muscle tissue and cells that plays a role in regulating the microfilament network.

capsaicin is an alkaloid irritating to the skin and mucous membranes. It is the pungent active principle in capsicum (cayenne), used as a topical counterirritant and analgesic.

cartilage is a specialized, fibrous connective tissue, forming most of the temporary skeleton of the embryo, providing a model in which most of the bones develop, and constituting an important part of the growth mechanism of the organism. It exists in several types, the most important of which are hyaline cartilage, elastic cartilage, and fibrocartilage.

cell migration is a central process in the development and maintenance of multi-cellular organisms. Tissue formation during embryonic development, wound healing and immune responses all require the orchestrated movement of cells in a particular direction to a specific location.

cell signaling is the process by which a cell receives and acts on some external chemical or physical signal, such as a hormone, including receiving the information at specific receptors in the plasma membrane, conveying the signal across the plasma membrane into the cell, and subsequently inducing an intracellular chain of other signaling molecules, thereby stimulating a specific cellular response.

chondroblasts are immature cartilage cells which produce the cartilaginous matrix.

chromatin is the more readily stainable portion of the cell nucleus, forming a network of nuclear fibrils. It is a deoxyribonucleic acid attached to a protein (primarily histone) structure base and is the carrier of the genes in inheritance. It occurs in two states, euchromatin and heterochromatin, with different staining properties, and during cell division it coils and folds to form the metaphase chromosomes.

collagen is an abundant protein that constitutes a major component of fascia, giving it strength and flexibility. At least 14 types exist, each composed of tropocollagen units that share a common triple-helical shape but that vary somewhat in composition between types, with the types being localized to different tissues, stages, or functions. In some types, including the most common, Type I, the tropocollagen rods associate to form fibrils or fibers; in other types the rods are not fibrillar but are associated with fibrillar collagens, while in others they form nonfibrillar, nonperiodic but structured networks.

collagenoblasts are cells that arise from fibroblasts and as they mature, are associated with the production of collagen. They form cartilage and bone by metaplasia and proliferate at sites of chronic inflammation.

compartment syndrome involves the compression of nerves and blood vessels within a fascial compartment. This leads to impaired blood flow and muscle and nerve damage.

confocal microscopy is an optical imaging technique used to increase micrograph contrast and/or to reconstruct three-dimensional images by using a spatial pinhole to eliminate out-of-focus light or flare in specimens that are thicker than the focal plane.

connexin is the primary protein component of connexon, the functional unit of a gap junction.

creep refers to the time-dependent tendency of a tissue to deform permanently as a result of application and maintenance of a stress at a set level.

cytokines are a generic term for non-antibody proteins released by one cell population (e.g., primed T lymphocytes) on contact with specific antigens, which act as intercellular mediators, as in the generation of an immune response.

cytoskeleton is the conspicuous internal reinforcement in the cytoplasm of a cell, consisting of tonofibrils, terminal web, or other microfilaments.

deep fascia is the dense fibrous fascia that interpenetrates and surrounds the muscles, bones, nerves and blood vessels of the body.

deformation is the process of adapting in shape or form, as when erythrocytes change in shape as they pass through capillaries. In dysmorphology, deformation refers to a type of structural defect characterized by the abnormal form or position of a body part, caused by a nondisruptive mechanical force

differentiated myofibroblast describes a myofibroblast that is capable of expressing alpha smooth muscle actin.

Dupuytren’s contracture isa painless thickening and contracture of the palmar fascia. dynamometer is an instrument for measuring the force of muscular contraction.

Ehlers-Danlos syndrome is a group of inherited disorders of the connective tissue, occurring in at least ten types, based on clinical, genetic, and biochemical evidence, varying in severity from mild to lethal, and transmitted genetically as autosomal recessive, autosomal dominant, or X-linked recessive traits. The major manifestations include hyperextensible skin and joints, easy bruisability, friability of tissues with bleeding and poor wound healing, calcified subcutaneous spheroids, and pseudotumors. Variably present in some types are cardiovascular, gastrointestinal, orthopedic, and ocular defects.

elastin is a yellow scleroprotein, the essential constituent of yellow elastic connective tissue. It is brittle when dry, but when moist is flexible and elastic.

electrogenic spasm refers to involuntary, pathologic contractions arising from the electrical activity occurring in alpha motor neurons and motor endplates.

electron microscopy is an imaging technique that uses electrons to illuminate and create an image of a specimen. It has much higher magnification and resolving power than a light microscope, with magnifications up to about two million times compared to about two thousand, allowing it to see smaller objects and greater detail in these objects. Unlike a light microscope, which uses glass lenses to focus light, the electron microscope uses electrostatic and electromagnetic lenses to control the illumination and imaging of the specimen.

endomysium is the fascial layer that ensheaths single muscle fibers.

endoneurium  is  the innermost fascial layer of a peripheral nerve, forming an interstitial layer around each individual fiber outside the neurilemma.

endotenon is a thin fascial membrane within a tendon that invests each collagen fibril, each collagen fiber, and envelopes the primary, secondary and tertiary fiber bundles together.

endothelium is the layer of epithelial cells that lines the cavities of the heart, the lumina of blood and lymph vessels, and the serous cavities of the body.

enkephalins are either of two simple pentapeptides that function as neurotransmitters or neuromodulators at many locations in the brain and spinal cord and play a part in pain perception, movement, mood, behavior, and neuroendocrine regulation. They are also found in nerve plexuses and exocrine glands of the gastrointestinal tract.

eosinophilic fasciitis is an inflammation of the fasciae of the extremities, associated with eosinophilia, edema, and swelling. The etiology is unknown but it frequently occurs following strenuous exercise. Also called Shulman’s syndrome.

epimysium is the fascial layer which envelopes an entire muscle.

epineurium is the outermost fascial layer of a peripheral nerve, surrounding the entire nerve and containing its supplying blood vessels and lymphatics.

epitenon is a fine, loose connective tissue sheath covering a tendon over its entire length.

extra-cellular matrix refers to any material produced by cells and excreted to the extra-cellular space within the tissues. It takes the form of both ground substance and fibers and is composed chiefly of fibrous elements, proteins involved in cell adhesion, and glycosaminoglycans and other molecules. It serves as a scaffolding holding tissues together and its form and composition help determine tissue characteristics. In epithelia, it includes the basement membrane.

fascia is the soft tissue component of the connective tissue system. It interpenetrates and surrounds muscles, bones, organs, nerves, blood vessels and other structures. Fascia is an uninterrupted, three-dimensional web of tissue that extends from head to toe, from front to back, from interior to exterior. It is responsible for maintaining structural integrity; for providing support and protection; and acts as a shock absorber. Fascia has an essential role in hemodynamic and biochemical processes, and provides the matrix that allows for intercellular communication. After injury, it is the fascia that creates an environment for tissue repair. Fascia can refer to dense planar fascial sheets (such as the Fascia lata) as well as joint capsules, organ capsules, muscular septa, ligaments, retinacula, aponeuroses, tendons, myofascia, neurofascia, and other fibrous collagenous tissues.

fasciagenic describes a condition that originates in or is caused by the fascia.

fasciotomy is a surgical incision or transection of fascia, often performed to release pressure in compartment syndrome.

fibroblasts are flat elongated fascial cells with cytoplasmic processes at each end, having a flat, oval, vesicular nucleus. Fibroblasts, which differentiate into chondroblasts, collagenoblasts, and osteoblasts, and myofibroblasts form the fibrous tissues in the body, including tendons, aponeuroses, supporting and binding tissues of all sorts.

fibromyalgia is common chronic rheumatic syndrome characterized by widespread pain in fibrous tissues, muscles, tendons, and other connective tissues, resulting in painful muscles without weakness. The cause of this disorder is unknown, but poor sleep quality seems to be an important factor in its pathogenesis.

fibronectins are any of several related adhesive glycoproteins. One form circulates in plasma, acting as an opsonin; another is a cell-surface protein that mediates cellular adhesive interactions. Fibronectins are important in fascia, where they cross-link to collagen, and are also involved in aggregation of platelets.

fibronexus is an adhesion in a myofibroblast that links actin across the cell membrane to molecules in the extracellular matrix like fibronectin and collagen.

fibrosis is the formation of fibrous tissue, as in repair or replacement of parenchymatous elements.

florescent microscopy is a light microscope used to study properties of organic or inorganic substances using the phenomena of fluorescence and phosphorescence instead of, or in addition to, reflection and absorption.

gap junctions are a type of intercellular junction comprising a narrowed portion (about 3 nm) of the intercellular space that contains channels or pores composed of hexagonal arrays of membrane-spanning proteins around a central lumen (connexon) through which pass ions and small molecules such as most sugars, amino acids, nucleotides, vitamins, hormones, and cyclic AMP. In electrically excitable tissues, these gap junctions serve to transmit electrical impulses via ionic currents and are known as electrotonic synapses.

germ cells are part of the germline that contain inherited genetic material and are involved in all stages of gametogenesis.

glycosaminoglycans are any of several high molecular weight linear heteropolysaccharides having disaccharide repeating units containing an N-acetylhexosamine and a hexose or hexuronic acid; either or both residues may be sulfated. This class of compounds includes the chondroitin sulfates, dermatan sulfates, heparan sulfate and heparin, keratan sulfates, and hyaluronic acid. All except heparin occur in proteoglycans.

Golgi receptors are mechanosensory receptors found in dense proper fascia, in ligaments (Golgi end organs), in joint capsules, as well as around myotendinous junctions (Golgi tendon organs).

goniometer is a tool which measures a joint’s axis and range of motion.

granulation tissue is the perfused connective tissue matrix that replaces a fibrin clot in wound healing. The extracellular matrix of granulation tissue is created and modified by fibroblasts.

hyaluronic acid is a glycosaminoglycan that is part of the extra-cellular matrix of synovial fluid, vitreous humor, cartilage, blood vessels, skin, and the umbilical cord. Along with lubricin, it maintains viscosity of the Extra Cellular Matrix allowing for necessary lubrication of certain tissues.

hypermobility refers to a greater than normal range of motion in a joint, which may occur naturally in otherwise normal persons or may be a sign of joint instability. Also known as laxity.

hypertonia refers toexcessive tone of the skeletal muscles that increases their resistance to passive stretching.

hypertrophy isthe enlargement or overgrowth of an organ or part due to an increase in size of its constituent cells.

hypocapnia is a deficiency of carbon dioxide in the blood, resulting from hyperventilation and eventually leading to alkalosis.

hysteresis is a property of systems that do not instantly react to the forces applied to them, but react slowly, or do not return completely to their original state.

immunocytochemistry relates to chemicals interacting with immune responses of cells within the host.

immunohistochemistry refers to the process of localizing proteins in cells of a tissue section, exploiting the principle of antibodies binding specifically to antigens in biological tissues.

immunofluorescence is the labeling of antibodies or antigens with fluorescent dyes. This technique is often used to visualize subcellular distribution of biomolecules of interest. Immunofluorescent labeled tissue sections are studied using fluorescent or confocal microscopy.

immunoassay is a biochemical test that measures the concentration of a substance in a biological liquid, typically serum or urine, using the reaction of an antibody or antibodies to its antigen.

integrins refer to any of a family of heterodimeric cell-adhesion receptors, consisting of two noncovalently linked polypeptide chains, designated α and β, that mediate cell-to-cell and cell-to-extra-cellular matrix interactions.

interferon-gamma is a dimerized soluble cytokine that is secreted by T lymphocytes and NK cells only. Also known as immune interferon, it has antiviral, immunoregulatory, and anti-tumour properties. It alters transcription in up to 30 genes producing a variety of physiological and cellular responses.

interleukin is a generic term for a group of multifunctional cytokines that are produced by a variety of lymphoid and nonlymphoid cells and have effects at least partly within the lymphopoietic system; originally believed to be produced chiefly by and to act chiefly upon leukocytes.

interstitial fluid is the extra-cellular fluid that bathes the cells of most tissues but which is not within the confines of the blood or lymph vessels and is not a trans-cellular fluid. It is formed by filtration through the blood capillaries and is drained away as lymph. It is the extra-cellular fluid volume minus the lymph volume, the plasma volume, and the trans-cellular fluid volume.

invaginations are inward folds of tissue, as in the formation of a cleavage furrow during cytokinesis.

kinins are proteins in the blood that influence certain muscle contractions, affect blood pressure (especially hypotension or low blood pressure), increase blood flow throughout the body, increase the permeability of small capillaries, and stimulate pain receptors.

lamellipodia are delicate sheet-like extensions of cytoplasm which form transient adhesions with the cell substrate and wave gently, enabling the cell to move along the substrate.

laminin is an adhesive glycoprotein component of the basement membrane. It binds to heparan sulfate, type IV collagen, and specific cell-surface receptors and is involved in the attachment of epithelial cells to underlying connective tissue.

ligament is a band of fascia that connects bones or supports viscera. Some ligaments are distinct fibrous structures; some are folds of fascia or of indurated peritoneum; still others are relics of fetal vessels or organs.

lysyl oxidase-like protein 1 is an enzyme responsible for elastin cross linking and a close homolog of lysyl oxidase. It plays a significant role in directing enzymatic deposition onto elastic fibers by mediating interactions with tropoelastin. It is associated with extra-cellular matrix remodeling during active fibrotic disorders and in the early stromal reaction of breast cancer.

lysophosphatidate is any phosphatidic acid–containing phospholipid that lacks one of its fatty acyl groups. The compounds are present as minor constituents of cell membranes as a result of phospholipid metabolism and are so named for their membranolytic qualities at high concentrations.

macrophages are any of the many forms of mononuclear phagocytes found in tissues. Most are large cells with a round or indented nucleus; a well-developed Golgi apparatus; abundant endocytotic vacuoles, lysosomes, and phagolysosomes; and a plasma membrane covered with ruffles or microvilli. Their functions include nonspecific phagocytosis and pinocytosis; specific phagocytosis of opsonized microorganisms; killing of ingested microorganisms; digestion and presentation of antigens to T and B lymphocytes; and secretion of many different products, including enzymes (lysozyme, collagenases, elastase), acid hydrolases, several complement components and coagulation factors, prostaglandins and leukotrienes, and regulatory molecules such as interferon and interleukin-1.

Marfan’s syndrome is a disorder of connective tissue which causes skeletal defects typically recognized in a tall, lanky person. A person with Marfan syndrome may exhibit long limbs and spider-like fingers, chest abnormalities, curvature of the spine and a particular set of facial features including a highly arched palate, and crowded teeth.

mechanoreceptors are sensory receptors that respond to mechanical pressure or deformation. They include Pacinian corpuscles, Meissner’s corpuscles, Merkel’s discs, Ruffini corpuscles, and some interstitial nerve endings.

mechanotransduction is the mechanism by which cells convert mechanical stimulus into chemical activity.

mepyramine is an antihistaminic pharmacological substance this frequently used as an in vitro contractile agent for tissues containing myofibroblasts.

merosin is the collective name for laminins that share a common subunit, the laminin alpha 2 chain.

metalloprotein matrix is a group of endopeptidases that hydrolyze proteins of the extra-cellular matrix.

microdialysis is a diagnostic technique that uses an ultra-fine needle to biopsy the chemical components of the fluid in the extra-cellular space of tissues.

mitogen-activated protein kinases (MAPK) – are serine/threonine-specific protein kinases that respond to extracellular stimuli (mitogens) and regulate various cellular activities, such as gene expression, mitosis, differentiation, and cell survival/apoptosis.

morphogenesis is the evolution and development of form, as in the development of the shape of a particular organ or part of the body.

morphometric analysis is a method of extracting measurements from shapes to study the "form follows function" aspect of biology, mapping the changes in an organism’s shape in regards to its function.

myofascial pain syndrome is achronic musculoskeletal pain disorder associated with local or referred pain, decreased range of motion, autonomic phenomena, local twitch response in the affected muscle, and muscle weakness without atrophy.

myofibroblasts are atypical fibroblasts that combine the ultra-structural features of both fibroblasts and smooth muscle cells. Due to their expression of stress fiber bundles containing alpha smooth muscle actin and due to strengthened adhesion sites on their membrane, these cells possess a much higher contractile potential than normal fibroblasts.

myosin is the most abundant protein in muscle, occurring chiefly in the A band. Along with actin, it is responsible for the contraction and relaxation of muscle. Myosin has enzymatic properties, acting as an ATPase. It is the main constituent of the thick filaments of muscle fibers.

nervi nervorum are nerves that supply the epi-, peri-, and endoneurium.

neuromatrix is a hypothesized network of neurons in the brain, that, in addition to responding to sensory stimulation, could continuously generate a neurosignature, a characteristic pattern of impulses indicating that the body is intact and unequivocally one’s own.

neuropathy is a functional disturbance or pathological change in the peripheral nervous system.

neuroplasticity refers to the changes that occur in the organization of the brain as a result of experience.

neutrophil elastase is an important protease enzyme that when expressed aberrantly can cause emphysema or emphysematous changes.

nociceptors are receptors for pain that are activated by physical, mechanical, thermal, electrical or chemical stimuli.

osteoblasts are cells that arises from fibroblasts and are associated with the production of bone.

osteogenesis imperfecta is a congenital disease caused by a genetic defect that affects type 1 collagen and results in extremely fragile bones. Also called brittle bone disease.

oxytocin is a nonapeptide secreted by the magnocellular neurons of the hypothalamus and stored in the neurohypophysis along with vasopressin. It promotes uterine contractions, milk ejection, contributes to the second stage of labor and is released during orgasm in both sexes. In the brain, oxytocin regulates circadian homeostasis, such as body temperature, activity level, and wakefulness and is involved in social recognition, bonding, and trust formation.

Pacinian corpuscles are lamellar or lamellated large encapsulated nerve endings located in fascia that are sensitive to pressure, vibration and acceleration of movement

pelvic organ prolapse is a general term that may include prolapse of the bladder (cystocele), the urethra (urethrocele), the uterus (uterine prolapse), the vagina (vaginal vault prolapse), the small bowel (enterocele), or the rectum (rectocele).

perimysium is the fascial membrane which groups individual muscle fibers (between 10 to 100+) into bundles or fascicles.

perineurium is an intermediate layer of fascia in a peripheral nerve, surrounding each bundle (fasciculus) of nerve fibers.

peritenon is the outer fascial layer of a tendon in tendons that are contained within a synovial sheath.

Peyronie disease is a fascial thickening that deforms the penis, distorting the shape of an erection.

phase contrast microscopy is an optical illumination technique in which small phase shifts in the light passing through a transparent specimen are converted into amplitude or contrast changes in the image.

phosphorylation is the introduction of a phosphate group into an organic molecule.

piezoelectric is the ability of some materials to generate an electric potential in response to applied mechanical stress.

plantar fasciitis refers to an inflammatory condition of the plantar fascia

plantar fibromatosis refers to the formation of fibrous, tumor-like nodules arising from the deep layer of the plantar fascia, manifested as single or multiple nodular swellings, sometimes accompanied by pain but is usually unassociated with contractures.

pressure algometer is an instrument that measures mechanical nociceptive thresholds.

pre-stress – endogenous tension.

procollagen is the precursor molecule of collagen, synthesized in the fibroblast, osteoblast, etc., and cleaved to form collagen extra-cellularly.

proprioception is perception mediated by sensory nerve endings found in muscles and fascia, which give information concerning movement and position of the body.

proteoglycans are polysaccharide-proteins that are found in the extra-cellular matrix of fascia, composed mainly of polysaccharide chains, particularly glycosaminoglycans, as well as minor protein components that form large complexes, both to other proteoglycans, to hyaluronan and to fibrous matrix proteins (such as collagen). They are also involved in binding cations (such as sodium, potassium and calcium) and water, and also regulating the movement of molecules through the matrix. Evidence also shows they can affect the activity and stability of proteins and signaling molecules within the matrix.

proteolysis is the directed degradation (digestion) of proteins by cellular enzymes called proteases or by intramolecular digestion.

proto-myofibroblasts are myofibroblasts that do not contain alpha smooth muscle actin, but can be distinguished from fibroblasts by the presence of stress fibers.

pseudopodium is a temporary cytoplasmic extrusion by means of which an ameba or other ameboid organism or cell moves about or engulfs food. Pseudopodia are of four types: axopodia, filopodia, lobopodia, and reticulopodia.

reticular fibers are fascial fibers composed of collagen type III that form the reticular framework of lymphoid and myeloid tissue and also occur in the interstitial tissue of glandular organs, the papillary layer of the skin, and elsewhere.

retinaculum is a thickened band of fascia that retains an organ or tissue in place.

rhoA is a small GTPase protein known to regulate the actin cytoskeleton in the formation of stress fibers. It acts upon two known effector proteins: ROCK1 (Rho-associated, coiled-coil containing protein kinase 1) and DIAPH1 (diaphanous homolog 1 (Drosophila)).

Ruffini endings are a type of lamellated corpuscle that are slowly-adapting receptors for sensations of continuous pressure.

sarcoplasmic reticulum is a special form of agranular reticulum found in the sarcoplasm of striated muscle and comprising a system of smooth-surfaced tubules forming a plexus around each myofibril.

sclerosis is aninduration or hardening caused by inflammation, fascial thickening, or disease of the interstitial fluid.

serotonin is a monoamine vasoconstrictor, synthesized in the intestinal chromaffin cells or in central or peripheral neurons and found in high concentrations in many body tissues, including the intestinal mucosa, pineal body, and central nervous system.

spasmodic torticollis refers to intermittent dystonia and spasms of the cervical muscles, particularly the sternocleidomastoid and trapezius. This results in distorted posture, exhibited by a twisting of the neck and an unnatural position of the head. Also called wry neck.

substance P is a short-chain polypeptide that functions as a neurotransmitter and as a neuromodulator.

sulcus vocalis is a groove or infolding of mucosa along the surface of the vocal fold. In the area of the sulcus, the mucosa is scarred down to the underlying vocal ligament, giving it a retracted appearance.

superficial fascia is comprised mainly of loose areolar connective tissue and adipose and is the layer that primarily determines the shape of a body. In addition to its subcutaneous presence, this type of fascia surrounds organs and glands, neurovascular bundles, and is found at many other locations.

surface electromyography is a technique in which electrodes are placed on (not into) the skin overlying a muscle to detect the electrical activity of the muscle.

tendon is a fibrous cord of fascia by which a muscle is attached.

tendon sheath is a membranous sleeve which envelops the tendon and creates a lubricated low-friction environment for easy movement.

tensegrity is the property of materials made strong by the unison of tensioned and compressed parts.

thixotropy is the property of a material to show a time-dependent change in viscosity. The longer it is subjected to shear forces, the lower its viscosity.

transdifferentiation is a biological process that occurs when a non-stem cell transforms into a different type of cell, or when an already differentiated stem cell creates cells outside its already established differentiation.

transforming growth factor refers to any of several proteins secreted by transformed cells and stimulating growth of normal cells, although not causing transformation. TGF-α binds the epidermal growth factor receptor and also stimulates growth of microvascular endothelial cells. TGF-β exists as several subtypes, all of which are found in hematopoietic tissue, stimulate wound healing, and in vitro are antagonists of lymphopoiesis and myelopoiesis.

trismus has been previously defined as a tonic contraction of the muscles of mastication. In the past, this word was often used to describe the effects of tetanus, also called ‘lock-jaw’. More recently, the term ‘trismus’ has been used to describe any restriction to mouth opening, including restrictions caused by trauma, surgery, radiation or temporomandibular joint dysfunction.

tropocollagen is the basic structural unit of collagen; a helical structure consisting of three polypeptide chains, each chain composed of about a thousand amino acids, coiled around each other to form a spiral and stabilized by inter- and intrachain covalent bonds. It is rich in glycine, proline, hydroxyproline, and hydroxylysine; the last two rarely occur in other proteins.

tropoelastin  is the precursor of elastin.

tropomyosin along with troponin, regulates the shortening of the muscle protein filaments actin and myosin. In the absence of nerve impulses to muscle fibers, tropomyosin blocks interaction between myosin crossbridges and actin filaments.

tympanoplasty is a surgical reconstruction of the hearing mechanism of the middle ear performed by grafting a small patch from a vein or fascia onto the eardrum to repair the tear.

ultrasound elastography is a non-invasive imaging method to measure stiffness or strain of soft tissue or to provide images of tissue morphology or other biomechanical information.

vacuoles refer to any small space or cavity formed in the protoplasm of a cell.

versican is a large chondroitin sulfate proteoglycan.

vimentin filaments are intermediate filaments of the cytoskeleton that are responsible for maintaining cell integrity. They act as cytoskeletal support structures, play a role in mitosis, and are clustered particularly around the nucleus, probably helping to control its location. In cells containing more than one type of intermediate filament, vimentin filaments are always present.

vinculin is a protein found in muscle, fibroblasts, and epithelial cells that binds actin and appears to mediate attachment of actin filaments to integral proteins of the plasma membrane.

viscoelastic describes materials that exhibit both viscous and elastic characteristics when undergoing plastic deformation. Viscous materials, like honey, resist shear flow and strain linearly with time when a stress is applied. Elastic materials strain instantaneously when stretched and just as quickly return to their original state once the stress is removed. Viscoelastic materials have elements of both of these properties and, as such, exhibit time dependent strain.

vitronectin is a multifunctional adhesive glycoprotein occurring in serum and various tissues and having binding sites for integrins, collagen, heparin, complement components and perforin. Its functions include regulation of the coagulation, fibrinolytic, and complement cascades, and it plays a role in hemostasis, wound healing, tissue remodeling, and cancer. It binds plasminogen activator inhibitor; mediates the inflammatory and repair reactions occurring at sites of tissue injury; and promotes adhesion, spreading, and migration of cells.

Wartenberg test is a simple but precise test to assist examination of increased muscle tone at the knee. Originally developed for persons with Parkinsons disease, it has been used in other spastic conditions.

Western blot (immunoblot) is a method to detect a specific protein in a given sample of tissue homogenate or extract.

Wolff’s law is the theory developed by 19th century anatomist/surgeon Julius Wolff that states that bone in a healthy person or animal will adapt to the loads it is placed under. If loading on a particular bone increases, the bone will remodel itself over time to become stronger to resist that sort of loading. The converse is true as well: if the loading on a bone decreases, the bone will become weaker due to turnover as it is less metabolically costly to maintain and there is no stimulus for continued remodeling that is required to maintain bone mass.

Prepared by Kim LeMoon