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sign(sīn) an indication of the existence of something; any objective evidence of a disease, i.e., such evidence as is perceptible to the examining physician, as opposed to the subjective sensations (symptoms) of the patient.
signAn objective clinical defect or change that is associated with a particular disorder.
SIGNSottish Intercollegiate Guidelines Network. An organisation established in 1993 by the Academy of Royal Colleges and their Faculties in Scotland, and approved by NHS Evidence, to develop evidence-based clinical practice guidelines for NHS-Scotland, and protocols for treating certain diseases and conditions—e.g., diabetes and back pain.
signMedtalk A defect or abnormality which is associated with a particular disorder. Related terms are Accordion sign, Air meniscus sign, Amputation sign, Angel wing sign, Aortic nipple sign, Apical cap sign, Applesauce sign, Arrowhead sign, Asterisk sign, Bald sac sign, Banana sign, Battle sign, Beak sign, Bird's sign, Bird beak sign, Blade of grass sign, Blue tongue sign, Bowler hat sign, Bozzolo sign, Branham sign, Broken ring sign, Broken straw sign, Brudzinski sign, Candy cane sign, Carman's meniscus sign, Cat's paw sign, Celery stick sign, Chaddock sign, Chadwick sign, 'Chandelier sign,' Chinese lantern sign, Chvostek sign, Clenched fist sign, Cluster of grapes sign, Cobrahead sign, Collar sign, Colon cut-off sign, Comet tail sign, Cracked-pot sign, Cracker sign, Curbstone sign, Cullen sign, Cut-off sign, Dagger sign, Deciduous tree in winter sign, Delta sign, DeMusset sign, Dimple sign, Doll's eye sign, Donohue-Fauver sign, Double bubble sign, Double condom sign, Double duct sign, Double wall sign, Dough sign, Doughnut sign, Drawer sign, Drooping lily sign, E sign, Einstein sign, Ellipse sign, Ewart sign, Eyelash sign, FBI sign, Fifth vital sign, Figure 3 sign, Fishhook sign, Flag sign, Flat waist sign, Football sign, Friend sign, Frog sign, Grey Turner sign, Groove sign, H bomb sign, Half moon sign, Hampton sign, Head drop sign, Heel pad sign, Hegar sign, Hill sign, Hilum overlay sign, Hoffman sign, Homan sign, Hot air balloon sign, Hump sign, Hump & dip sign, Iceberg sign, Inverted comma sign, Inverted mushroom & stem sign, Inverted 3 sign, Inverted U sign, Inverted umbrella sign, Jail bars sign, Jello™ sign, Jet sign, Joffrey sign, Kussmaul sign, Kehr sign, Kernig sign, Kestenbaum sign, Key sign, Keyhole sign, Lachman sign, Lasègue sign, Lemon sign, Lhermitte sign, Lipstick sign, Luftsichel sign, Marcus Gunn sign, McMurray sign, Meningeal sign, Meniscus sign, Mickey Mouse sign, Milk rejection sign, Möbius sign, Mogul sign, Monocle sign, Moro sign, Moviegoer sign, Mulder sign, Musset sign, Napoleon's hat sign, Nikolsky's sign, Notch sign, Nuchal translucency sign, Numb chin sign, Number 3 sign, Ober sign, Obturator sign, Okra sign, Omega sign, One bone-two bone sign, One sign, two sign, three sign, Overhanging ledge sign, Osler sign, Padlock sign, Pencil-in-cup sign, Peninsula sign, Phalen sign, Playboy Bunny sign, Plump hilus sign, Psoas sign, Puddle sign, Pyloric string sign, Pyriform sign, Quarter moon sign, Reverse 5 sign, Reverse 3 sign, Rigid loop sign, Rim sign, Ring sign, Romberg sign, Rope sign, Rovsing sign, Sagging rope sign, Sail sign, Sanctuary sign, Scarf sign, Scotty dog sign, Setting sun sign, Shaggy heart sign, Shelf sign, Signet ring sign, Snowman sign, Snow white sign, Square root sign, Step-off sign, String sign, String of beads sign, Sulcus sign, Terry Thomas sign, Thorn sign, Thumb & little finger sign, Thumb sign, Thymic wave sign, Tinnel sign, Tinted spectacles sign, Tit sign, Tooth sign, Toothpaste sign, Track sign, Trident sign, Twinkling star sign, Vacuum sign, Vital sign, 'Waiter accepting a tip' sign, Wall sign, Water lily sign, Westermark sign, Westphal sign, Whalebone in a corset sign, White line sign, Winterbottom sign, Wrist sign
signAn objective indication of disease, perceptible by an external observer. Compare SYMPTOM.
signobjective features of disease, and noted by examining clinician (contrast with symptoms); note: eponymous signs are denoted as ‘positive’ when their characteristics are present
Babinski's sign characteristics of an upper motor neurone lesion (UMNL; e.g. cerebrovascular accident; cerebral palsy), i.e. hip, knee, elbow and wrist flexion, ankle plantar flexions, forearm pronation, and an extensor plantar response on contralateral side to UMNL (see response, extensor plantar)
Chaddock's sign stimulation of lateral malleolar skin causes hallux extension at first metatarsophalangeal joint; diagnostic of corticospinal (motor tract) reflex path pathology
Chvostek's sign hemifacial tic, induced by tapping the facial nerve just below cheek bone; indicative of hypercalcaemia
clenched-fist sign pressing the clenched fist against anterior central chest wall; characteristic of angina pectoris
Erb–Westphal sign loss of knee jerk reflex; characteristic of spinal cord motor tract pathology
Gower's sign attaining upright posture from sitting by pushing with the hands against anterior thighs (‘climbing up the legs’); characteristic of Duchenne muscular dystrophy
Homan's sign calf pain on ankle dorsiflexion; characteristic of calf deep-vein thrombosis
Hutchinson's sign pigment ‘overspill’/ ‘washout’ into surrounding tissues from a melanoma; denotes local spread of lesion
Leser–Trelat sign rapid development of multiple seborrhoeic keratotic skin lesions; associated with underlying malignancy
Lhermitte's sign sudden ‘electrical’ pains that extend down the spine when head is flexed on neck; characteristic of multiple sclerosis and cervical cord compression
oil drop sign small area of yellowish onycholysis, caused by elevation of nail plate from bed; characteristic of psoriasis
Remak's sign pain in response to innocuous stimuli; characteristic of polyneuritis and painful neuropathies, e.g. diabetic neuropathy and complex regional pain syndromes
Romberg's sign loss of/poor balance when standing with eyes closed; characteristic of proprioception loss or cerebellar dysfunction
Sever's sign exacerbation of heel pain when standing on tiptoe on affected side; characteristic of calcaneal apophysitis (Sever's disease)
Stewart–Holmes sign; rebound phenomenon inability to control limb movement when passive limb resistance is suddenly released; characteristic of cerebellar dysfunction
suction sign increased ankle joint movement, with formation of a depression between lateral malleolus and talus (demonstrated by positive anterior drawer test); diagnostic of anterior talofibular ligament dysfunction
Sullivan's sign; sunray sign; daylight sign separation/divergence of two adjacent toes; characteristic of forefoot rheumatoid disease (i.e. metatarsophalangeal joint synovitis, intermetatarsal oedema, bursitis) or plantar digital neuroma
Tinel's sign dermatomal tingling/paraesthesia on percussion of subserving nerve trunk; characteristic of nerve trunk compression, nerve injury or early nerve repair subsequent to nerve lesion; e.g. paraesthesia in sole of a foot with tarsal tunnel syndrome, when tibial nerve is percussed posterior to medial malleolus; or in palm of a hand with carpal tunnel syndrome, when radial nerve is percussed at volar aspect of wrist
‘too many toes’ sign visualization of fifth, fourth, third, second and even first toes when patient is viewed from behind when standing in relaxed calcaneal stance; characteristic of excess foot pronation/forefoot abduction
Trendelenburg's sign anterior tilt of upper pelvis on flexion of hip and knee of non-weight-bearing limb (i.e. during swing phase of gait) whilst weight-bearing on other leg (e.g. observed as patient climbs stairs); characteristic of congenital hip joint dislocation or hip adductor weakness (normally non-weight-bearing pelvis tilts upward during swing phase of gait)
Trousseau's sign sharp flexion movements of the wrist and metacarpophalangeal joints and extension of the fingers when a blood pressure cuff, inflated to above systolic pressure, is left in situ for 3 mins; characteristic of latent tetany and indicative of hypocalcaemia
vital signs signs of life (breathing, heart beat and sustained blood pressure)
Ward's sign distended/engorged superficial dorsal foot and lower-leg veins due to venous hypertension and secondary to arteriovenous shunting; characteristic of diabetic autonomic neuropathy
Argyll Robertson sign See Argyll Robertson pupil.
Bell's sign Bell's phenomenon occurring on the affected side in Bell's palsy.
Bjerrum's sign See Bjerrum's scotoma.
Cogan's lid twitch sign A twitch of the upper eyelid in an eye with ptosis when the patient is asked to look in the primary position following a downward look. The eyelid then returns to its ptosis position. This condition occurs in myasthenia gravis.
Collier's sign Unilateral, or more commonly bilateral, eyelid retraction that exposes an unusual amount of the sclera of the eye above and below the iris; it gives the person a frightened or startled expression. It is due to a midbrain lesion. See Parinaud's syndrome.
sign convention A set of conventions regulating the direction of distances, lengths, and angles measured in geometrical optics. The most common is the New Cartesian Sign Convention. It stipulates: (1) All distances are measured from the lens, refracting surface or mirror. Those in the same direction as the incident light, which is drawn travelling from left to right, are positive. Those in the opposite direction are negative. (2) All distances are measured from the axis. Those above are positive. Those below are negative. (3) Angles are measured from the incident ray to the axis, with anticlockwise angles positive and clockwise angles negative. (4) The power of a converging lens is positive and that of a diverging lens is negative (Fig. S7). See focal length; Lagrange's law; law of refraction; Newton's formula; fundamental paraxial equation.
Dalrymple's sign Retraction of the eyelids causing an abnormally widened palpebral fissure, in primary gaze. This is a sign of Graves' disease. The patient appears to stare and to be frightened as some white sclera may be seen above the upper limbus.
doll's eye sign See doll's head phenomenon.
von Graefe's sign Immobility or lagging of the upper eyelid when looking downward. This is a sign of Graves' disease.
Gunn's crossing sign Tapering of veins on either side of the arteriovenous crossings seen in hypertensive retinopathy.
Hutchinson's sign A triad of signs present in congenital syphilis. They are interstitial keratitis, notched teeth and deafness.
local sign See oculocentric direction.
Moebius' sign Convergence weakness occurring in Graves' disease.
Mizuo's sign See Mizuo's phenomenon.
Munson's sign A sign observed in keratoconus in which the lower lid is bulging as a cone when the patient looks downward.
pseudo-von Graefe sign See aberrant regeneration.
Rizzuti's sign An arrowhead pattern near the nasal part of the corneoscleral limbus, sometimes seen in advanced keratoconus.
Salus' sign Retinal vein deflection from its normal course at arteriovenous crossings seen in hypertensive retinopathy.
Seidel's sign See Seidel's scotoma.
Shafer's sign The presence of pigment granules of various sizes floating in the anterior vitreous. They usually result from a retinal break/s, which may progress into rhegmatogenous retinal detachment. Then the pigment cells appear as small black dust-like particles ('tobacco dust') seen on clinical examination.
Vogt's sign Loss of the normal shagreen of the front surface of the crystalline lens indicating anterior capsular cataract. See crocodile shagreen.
Uhthoff's sign See Uhthoff's symptom.