F
fabella a sesamoid bone sometimes found posterior to the knee joint.
facet a small, smooth, flat surface of a bone or a calculus.
facial associated with the face.
facial hemiatrophy a congenital condition, or a manifestation of scleroderma in which the structures on one side of the face are shrunken.
facial nerve seventh pair of cranial nerves. They supply the facial muscles, the salivary, lacrimal and nasal glands, and part of the tongue.
facial paralysis paralysis of muscles supplied by the facial nerve.
facies the appearance or the expression of the face. adenoid facies open mouthed, vacant expression due to deafness from enlarged pharyngeal tonsils (adenoids). Parkinson facies a mask-like appearance; saliva may trickle from the corners of the mouth.
facilitated diffusion process whereby larger non-fat-soluble molecules such as glucose pass into the cell by using a protein carrier molecule. No energy is required but there must be a concentration gradient.
faecalith a concretion formed in the bowel from faecal matter: it can cause obstruction and/or inflammation.
faecal softeners see laxatives.
faeces the waste material eliminated from the bowel, consisting mainly of indigestible cellulose, unabsorbed food, intestinal secretions, water, electrolytes and bacteria, etc.
failure to thrive failure to develop and grow at the expected rate, ascertained by consistent measurement of height and weight plotted on a growth chart. It may result from an organic disorder or have non-organic causes, such as poor feeding, maternal deprivation or psychosocial problems. Careful investigation is required to establish the cause.
faint a temporary loss of consciousness. See also syncope.
fallopian tubes see uterine tubes.
Fallot’s tetralogy a cyanotic congenital heart defect comprising a ventricular septal defect, narrowing of the right ventricular outflow tract (subvalvular pulmonary stenosis), right ventricular hypertrophy and malposition of the aorta overriding the ventricular septum. Amenable to corrective surgery.
false pelvis the wide expanded part of the pelvis above the brim.
falx a sickle-shaped structure.
falx cerebri that portion of the dura mater separating the two cerebral hemispheres.
familial adenomatous polyposis a dominantly inherited condition in which multiple polyps occur throughout the large bowel and which invariably leads to colon cancer. Polyps also occur in the stomach and duodenum.
Family Health Services (FHS) community-based services provided by family doctors, dentists, opticians and pharmacists as independent contractors. They are not directly employed by the NHS, but have contractual arrangements to practise in the NHS.
farad (F) a measure of capacitance, an electrical system has a capacitance of 1 farad if a charge of 1 coulomb held by the body results in a potential of 1 volt.
Faraday’s laws of electromagnetic induction (1) a change in the magnetic flux linked with a conductor induces an electromotive force in the conductor. (2) The size of the induced electromotive force is proportional to the rate of change of the magnetic flux linkage.
farmer’s lung see extrinsic allergic alveolitis.
fascia a connective tissue sheath consisting of fibrous tissue and fat which unites the skin to the underlying tissues. It also surrounds and separates many of the muscles, and, in some cases, holds them together.
fasciculus a little bundle, as of muscle or nerve.
fasciitis an abnormal benign growth which develops in the subcutaneous oral tissue, usually in the cheek. Inflammation of the connective tissue.
Fatal Accident Enquiry see coroner.
fatigue weariness. Physiological term for diminishing muscle reaction to stimulus applied. In sports medicine the failure of muscle(s) to maintain force (or power output) during sustained or repeated contractions.
fatigue fracture see stress fracture.
fatigue index (FI) the decline in power divided by the time (in seconds) interval between maximum (peak) and minimum power, recorded during an anaerobic power exercise test.
fatty acid hydrocarbon component of lipids. May be unsaturated (monounsaturated or polyunsaturated) or saturated depending on the number of double chemical bonds in their structure.
fatty degeneration tissue degeneration that leads to the appearance of fatty droplets in the cytoplasm; found especially in disease of heart, liver and kidney.
fatty liver accumulation of fat in the liver, an indication of diffuse liver disease or benign changes, demonstrated using grey scale ultrasound.
fat/water suppression a method that suppresses signal within the imaging volume from either fat or water protons by applying a frequency selective, saturation, radio frequency pulse in magnetic resonance imaging.
fauces the opening from the mouth into the pharynx, bounded above by the soft palate, below by the tongue. pillars of the fauces, anterior and posterior, lie laterally and surround the palatine tonsil.
febrile feverish; accompanied by fever. febrile convulsions occur in children who have an increased body temperature; they do not usually result in permanent brain damage. Most common between the ages of 6 months and 5 years. See also convulsions.
feedback a homeostatic control mechanism. It is usually negative feedback where a physiological process is slowed or ‘turned off’ by an increasing amount of product, for example, temperature control. Much more rarely in positive feedback the process is speeded up by high levels of the product, for example, normal blood clotting. feedback treatment See biofeedback.
femoral associated with the femur or thigh. Applied to the vein, artery, nerve and canal.
femoral arteriography a contrast agent is injected via a catheter in the femoral artery to demonstrate the arterial circulation of the leg.
femoral hernia protrusion through the femoral canal, alongside the femoral blood vessels as they pass into the thigh.
femoropopliteal usually, referring to the femoral and popliteal vessels.
femur the thigh bone, the longest and strongest bone in the body.
fenestra a window-like opening.
fenestra ovalis an oval opening between the middle and internal ear.
fenestra rotunda a round opening which lies below the fenestra ovalis.
fenestration a perforation, opening or pore, the glomerular capillaries of the nephron, which form part of the filtration membrane, are adapted for permeability and filtration by the presence of fenestrations. A surgical opening (or fenestra) in the inner ear to ease the deafness caused by otosclerosis.
ferritin an iron–protein complex. A storage form of iron.
ferromagnetic a substance that if placed in a magnetic field becomes magnetized and once the magnetic field is removed it retains its magnetism, for example iron, cobalt or nickel. See also diamagnetic, paramagnetic, superparamagnetic.
ferromagnetism if an external magnetic force is applied to the material all the magnetic domains align in the same direction forming a strong magnet.
fetal age viability defined as when a baby can survive outside the womb, that is, 24 weeks gestational age.
fetal alcohol syndrome (FAS) stillbirth and fetal abnormality due to prenatal growth retardation caused by excessive maternal alcohol consumption during pregnancy.
fetal circulation circulation adapted for intrauterine life. Extra shunts and vessels (ductus venosus, ductus arteriosus, foramen ovale and umbilical vein) allows blood to largely bypass the liver, gastrointestinal tract and lungs, as their functions are covered by maternal systems and the placenta.
fetus the developmental stage from the eighth week of gestation until birth.
fetus papyraceus a dead fetus, one of a twin which has become flattened and mummified.
fever (pyrexia) an elevation of body temperature above normal. Designates some infectious conditions, for example, paratyphoid fever, scarlet fever, typhoid fever, etc.
fibre a thread-like structure.
fibre distribution data interface (FDDI) in computing a system similar to a token ring which uses fibreoptic cables to inform nodes when they can write to the network. See also nodes.
fibreoptics light is transmitted through flexible glass fibres which enable the user to ‘see round corners’. The technology utilized in endoscopic equipment.
fibril a component filament of a fibre; a small fibre.
fibrillation uncoordinated quivering contraction of muscle; referring usually to myocardial muscle. See also atrial fibrillation, cardiac arrest, ventricular fibrillation.
fibrin the insoluble matrix on which a blood clot is formed. Produced from soluble fibrinogen by the action of thrombin.
fibrinogen factor I of blood coagulation. A soluble plasma protein that is converted to fibrin by the action of thrombin.
fibroadenoma a benign tumour containing fibrous and glandular tissue.
fibroblast (fibrocyte) a blast cell that forms connective tissues. Involved during growth and tissue repair.
fibrocartilage cartilage containing fibrous tissue.
fibrocaseous a soft, cheesy mass infiltrated by fibrous tissue, formed by fibroblasts.
fibrocyst a fibroma which has undergone cystic degeneration.
fibrocystic associated with a fibrocyst.
fibrocystic disease bone cysts which may be solitary or generalized. If generalized and accompanied by decalcification of bone, it is symptomatic of hyperparathyroidism.
fibrocystic disease of breast the breast feels lumpy due to the presence of cysts, usually caused by hormone imbalance.
fibrocystic disease of pancreas cystic fibrosis.
fibroid a fibromuscular benign tumour usually found in the uterus may be on a stalk (pedunculate) protruding from the uterus, in the wall of the uterus or in the endometrial cavity. The location of fibroids can be described as intramural (embedded in the wall of the uterus), subserous (protruding from the serosal surface into the peritoneal cavity), or submucous (protruding into the endometrial surface).