Human health and medicine

Flail chest

Flail chest: fracture of 3+ adjacent ribs in 2+ places creating a paradoxically moving chest wall segment after blunt trauma. Treated with analgesia and ventilation; surgical rib fixation reduces ventilator days, pneumonia, and mortality.

FLAMENCO trial

FLAMENCO (Fitness League Against MENopause COst) trial, NCT02358109: Spanish randomized controlled trial at University of Granada testing a 16-week, 3-day/week multicomponent exercise program in 160 women aged 45-60, improving menopause symptoms, body composition, and quality of life.

Flap monitoring

Flap monitoring is the postoperative assessment of a transferred tissue flap's perfusion and viability, by bedside exam or devices, to catch vascular compromise early enough for salvage surgery.

Flash glucose monitoring

Flash glucose monitoring, also called intermittently scanned continuous glucose monitoring, is a wearable diabetes sensor that reads interstitial glucose from a filament in the upper arm when scanned.

FLASH radiotherapy

FLASH radiotherapy is a radiation therapy technique delivering doses at ultra-high dose rates above 40 Gy/s, over 1000 times faster than conventional radiotherapy, killing tumors normally while reducing normal tissue injury, with first-in-human treatment in 2018.

Flat feet

Flat feet, also known as pes planus, is a common condition in which the foot's arch is diminished or absent, and it usually needs no treatment.

Flatulence

Flatulence (flatus, farting) is passing intestinal gas through the rectum; normal at 8–14 times daily, caused by swallowed air and colonic bacterial fermentation, odor from sulfur compounds, managed by diet and low-FODMAP changes.

FLAURA trial

FLAURA (NCT02296125): phase 3 trial of first-line osimertinib versus gefitinib or erlotinib in 556 patients with EGFR-mutated advanced NSCLC; median PFS 18.9 vs 10.2 months, significant overall survival benefit, basis for FLAURA2.

Flavor

Flavor is the multisensory experience of eating, combining taste, retronasal smell, and trigeminal somatosensation, shaped by visual and sound cues; most people mistake it for taste alone and never notice the olfactory component.

FLAVOUR II trial

FLAVOUR II: 2020-2023 Chinese multicenter randomized non-inferiority trial (1,839 randomized, Lancet 2025) showing AI angiography-derived FFR-guided PCI non-inferior to IVUS guidance at 12 months with fewer stents.

Flavoxate

Flavoxate (Urispas, W-61) is a synthetic flavone urinary tract spasmolytic and competitive muscarinic antagonist, FDA-approved in 1970, used for symptomatic relief of dysuria, urgency, and bladder spasms.

Flecainide

Flecainide (flecainide acetate, trade name Tambocor) is a class IC antiarrhythmic drug blocking fast sodium channels, used for atrial fibrillation and approved by the FDA in 1984, but avoided after heart attacks.

Fleck corneal dystrophy

Fleck corneal dystrophy (FCD), or François-Neetens speckled corneal dystrophy, is a rare autosomal dominant PIKFYVE-related stromal corneal dystrophy with tiny non-progressive white flecks, normal vision, and no treatment required.

Flexibility (anatomy)

Flexibility (anatomy): joint range of motion and resistance to rotation, shaped by extracellular matrix, titin, and stretch tolerance; improved mainly by static, dynamic, and PNF stretching.

Flexible assertive community treatment

Flexible assertive community treatment (FACT), also called Function ACT, is a Dutch adaptation of assertive community treatment serving all people with severe mental illness in a catchment area.

Flexible bronchoscopy

Flexible bronchoscopy, also known as flexible fiberoptic bronchoscopy, is a pulmonary procedure in which a thin flexible endoscope is passed through the nose or mouth to visualize and sample the airways.

Flexible cystoscopy

Flexible cystoscopy is an endoscopic examination in which a thin, steerable camera tube is passed through the urethra into the bladder to inspect its lining, in use since 1973.

Flexible endoscopy

Flexible endoscopy is a diagnostic and therapeutic procedure in which a bendable fiber-optic or video endoscope is passed into hollow organs to inspect their lining, take biopsies, and deliver treatment.

Flexible fiberoptic laryngoscopy

Flexible fiberoptic laryngoscopy is an office-based endoscopic exam in which a thin, steerable scope passed through the nose views the pharynx and vocal cords during breathing and speech.

Flexible ureterorenoscopy

Flexible ureterorenoscopy is an endoscopic urological procedure in which a steerable flexible scope reaches the kidney to treat stones, first-line for renal calculi up to 2 cm.

Flexible ureteroscopy

Flexible ureteroscopy (FURS) is an endoscopic urological procedure in which a steerable flexible scope reaches the kidney to diagnose and treat stones, strictures, and urothelial cancers.

Oct 20, 2026

Flexion deformity

Flexion deformity, also called flexion contracture (ICD-11 FA31.2, ICD-10 M21.2), is a bent joint that cannot be straightened actively or passibly due to structural changes in muscle, tendon, ligament, or skin; common in knee osteoarthritis, neuromuscular disease, and brachial plexus birth injury, treated by stretching, bracing, casting, or surgery.

Flexor digitorum profundus muscle

Flexor digitorum profundus (FDP), deep forearm flexor muscle; flexes DIP joints of the four medial fingers, dual median/ulnar innervation, inserts on distal phalanges; site of jersey finger and quadrigia.

Flexor retinaculum of the hand

Flexor retinaculum of the hand, also called the transverse carpal ligament: fibrous band forming the carpal tunnel roof, attached to scaphoid, trapezium, pisiform, and hamate hook, retaining nine flexor tendons and the median nerve; released in carpal tunnel surgery.

Flibanserin

Flibanserin (Addyi) is a daily 5-HT1A agonist/5-HT2A antagonist pill for hypoactive sexual desire disorder in women, FDA-approved 2015 for premenopausal women and expanded December 2025 to women under 65; boxed warning for alcohol-related hypotension.

Flight of ideas

Flight of ideas (Ideenflucht) is a formal thought disorder of rapid, loosely linked topic shifts in pressured speech, a DSM-5 manic episode criterion in bipolar disorder, distinct from the subjective experience of racing thoughts.

Flindokalner

Flindokalner (BMS-204352, MaxiPost), a fluoro-oxindole potassium channel opener by Bristol-Myers Squibb; BK and Kv7.2-7.5 activator that failed phase III trials for acute ischemic stroke.

Floater

Floater (eye floater, myodesopsia): a dark spot, thread, or cobweb drifting across vision, caused by vitreous strands casting retinal shadows. Usually harmless; sudden new floaters with flashes signal possible retinal tear.

Flocculation Tests

Flocculation tests are serological precipitin assays in which antigen-antibody complexes form visible clumps over a narrow antigen-antibody ratio. Key examples: VDRL and RPR syphilis tests and the Ramon Lf test for toxoid vaccines.