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a three-cornered object, figure, or area, such as a delineated area on the surface of the body; called also trigone.
carotid triangle, inferior that between the median line of the neck in front, the sternocleidomastoid muscle, and the anterior belly of the omohyoid muscle.
carotid triangle, superior carotid trigone.
cephalic triangle one on the anteroposterior plane of the skull, between lines from the occiput to the forehead and to the chin, and from the chin to the forehead.
digastric triangle submandibular triangle.
Einthoven's triangle an imaginary equilateral triangle with the heart at its center, formed by the axes of the three bipolar limb leads.
Einthoven's triangle. Bipolar limb leads I, II, and III form Einthoven's triangle. Other standard positions for electrocardiographic leads are the augmented unipolar leads: aVR (right arm), aVL (left arm), and aVF (left leg). From Polaski and Tatro, 1996.
triangle of elbow a triangular area on the front of the elbow, bounded by the brachioradial muscle on the outside and the round pronator muscle inside, with the base toward the humerus.
triangle of election superior carotid triangle.
facial triangle a triangular area whose points are the basion and the alveolar and nasal points.
femoral triangle the area formed superiorly by the inguinal ligament, laterally by the sartorius muscle, and medially by the adductor longus muscle; called also Scarpa's triangle.
infraclavicular triangle that formed by the clavicle above, the upper border of the greater pectoral muscle on the inside, and the anterior border of the deltoid muscle on the outside.
inguinal triangle the triangular area bounded by the inner edge of the sartorius muscle, the inguinal ligament, and the outer edge of the long adductor muscle.
lumbocostoabdominal triangle that lying between the external oblique muscle of the abdomen, the posterior inferior serratus muscle, the erector muscle of the spine, and the internal oblique muscle of the abdomen.
occipital triangle the area bounded by the sternocleidomastoid muscle in front, the trapezius muscle behind, and the omohyoid muscle below.
Scarpa's triangle femoral triangle.
subclavian triangle a triangular area bounded by the clavicle, the sternocleidomastoid muscle, and the omohyoid muscle.
suboccipital triangle that lying between the posterior greater rectus muscle of the head and the superior and inferior oblique muscles of the head.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


, pl.


(trī-gō'nŭm, -nă), [TA]
Any triangular area. See: triangle.
Synonym(s): trigone (1) [TA]
[L., fr. G. trigōnon, a triangle]
Farlex Partner Medical Dictionary © Farlex 2012


, pl. trigona (trī-gō'nŭm, -nă) [TA]
Any triangular area.
See also: triangle
Synonym(s): trigone (1) .
[L., fr. G. trigōnon, a triangle]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
En el presente estudio se determino la prevalencia del Os trigonum en poblacion mayor de 14 anos, ya que a esta edad el talo ya se encuentra osificado y es posible determinar la presencia de OT sin confundirlo con el centro de osificacion secundario del talo (Karasick & Schweitzer, 1996; Vasconcellos et al., 2013); y se clasifico en grupos segun sexo y grupo etario, ademas de una comparacion entre la prevalencia en pie derecho e izquierdo.
An os trigonum is a small bony ossicle located posterior to the talus.
Os trigonum sendromunun nadir goruldugu vurgulanmakla birlikte bu konuyla ilgili yeterli epidemiyolojik veriler bulunmamaktadir.
(3) Variations in normal osseous and soft-tissue anatomy that predispose one to PAI syndrome include a prominent down-slope of the posterior tibia, the presence of an os trigonum, a prominent posterior-talar process (Stieda process), (3) prominent tuberosity arising from the superior calcaneum, (3) and the presence of the posterior-intermalleolar ligament (PIML).
The types of bony impingement are an os trigonum, Stieda's process (Christian Hermann Ludwig Stieda, German anatomist, 1837-1918), or Shepherd's fracture (Francis J.
It is important not to dismiss a fracture fragment located at the posterosuperior aspect of the talus as a normal variant an accessory ossicle called the os trigonum. (14) Accessory ossicles tend to be rounded with a well corticated margin, while fracture fragments may be irregular and demonstrate jagged edges.
Diagnosis is clinical for the most part, but plain x-ray films may confirm the presence of an os trigonum. Magnetic resonance imaging (MRI) is warranted for patients with persistent symptoms; it may reveal a hypertrophied synovial lining or other pathology (such as osteochondritis).
We discuss some of the more commonly symptomatic bones, namely the os acromiale, os styloideum, metacarpal and hallux sesamoids, patella, os trigonum, os calcaneus secundarius, accessory navicular, os peroneum, and os intermetatarseum.
1 1 1 1 Episinus angulatus 1 1 1 1 Episinus maculipes 1 1 1 1 Euryopis flavomaculata 1 1 1 1 Latrodectus geometricus 1 1 1 1 Neospintharus trigonum 1 1 1 1 Phoroncidia americana 1 1 1 1 Selkirkiella sp.
In these citizens, the space between the two heads is triangular and filled with fascia, and named Trigonum supraclavicularis minor and covered by cervical fascia (Mori).
Posterior ankle impingement syndrome (PAIS) is a painful, usually limited plantar flexion of the ankle joint due to posterior impingement of either soft tissue or a bony structure--e.g., an os trigonum or large posterior process of the talus (Stieda's process)--between the posterior distal end of the tibia (malleolus tertius) and the posterior tuberculum of the calcaneus (Fig.