Hesselbach's triangle

triangle /tri·an·gle/ (tri´ang-g'l) trigone; a three-cornered figure or area, such as on the surface of the body.

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anal triangle  the portion of the perineal region surrounding the anus.

carotid triangle, inferior  the part of the carotid trigone medial to the omohyoid muscle.

carotid triangle, superior  carotid trigone.

cephalic triangle  one on the anteroposterior plane of skull, between lines from the occiput to the forehead and to the chin, and from the chin to the forehead.

Codman's triangle  a triangular area visible radiographically where the periosteum, elevated by a bone tumor, rejoins the cortex of normal bone.

digastric triangle  submandibular t.

triangle of elbow  in front, the supinator longus on the outside and pronator teres inside, the base toward the humerus.

facial triangle  a triangle whose points are the basion, and alveolar and nasal points.

Farabeuf's triangle  one in the upper part of the neck bound by the internal jugular vein, the facial nerve, and the hypoglossal nerve.

femoral triangle 

1. the area formed superiorly by the inguinal ligament, laterally by the sartorius muscle, and medially by the adductor longus muscle.

2. the surface area of the thigh overlying this area.

frontal triangle  one bounded by the maximum frontal diameter and the lines to the glabella.

Hesselbach's triangle  inguinal t. (1).

iliofemoral triangle  one formed by Nélaton's line, another line through the superior iliac spine, and a third from this to the greater trochanter.

infraclavicular triangle  one formed by the clavicle above, upper border of the pectoralis major on the inside, and the anterior border of the deltoid on the outside.

inguinal triangle 

1. the area on the inferoanterior abdominal wall bounded by the rectus abdominis muscle, the inguinal ligament, and inferior epigastric vessels.

2. femoral t. (1).

triangle of Koch  a roughly triangular area on the septal wall of the right atrium, between the tricuspid valve, coronary sinus orifice, and tendon of Todaro, that marks the site of the atrioventricular node.

Triangle of Koch, at the apex of which lies the atrioventricular node.

Langenbeck's triangle  one whose apex is the anterior superior iliac spine, its base the anatomic neck of the femur, and its external side the external base of the greater trochanter.

Lesser's triangle  one formed by the hypoglossal nerve above, and the two bellies of the digastricus on the two sides.

lumbar triangle  Petit's t.

lumbocostoabdominal triangle  one between the obliquus externus, the serratus posterior inferior, the erector spinae, and the obliquus internus.

Macewen's triangle  mastoid fossa.

occipital triangle  one having the sternomastoid in front, the trapezius behind, and the omohyoid below.

occipital triangle, inferior  one having a line between the two mastoid processes as its base and the inion its apex.

omoclavicular triangle  subclavian t.

Pawlik's triangle  an area on the anterior vaginal wall corresponding to the trigone of the bladder.

Petit's triangle  the inferolateral margin of the latissimus dorsi and the external oblique muscle of the abdomen.

Scarpa's triangle  femoral t. (1).

subclavian triangle  a deep region of the neck: the triangular area bounded by the clavicle, sternocleidomastoid, and omohyoid.

submandibular triangle , submaxillary triangle the triangular region of the neck bounded by the mandible, the stylohyoid muscle and posterior belly of the digastric muscle, and the anterior belly of the digastric muscle.

suboccipital triangle  one between the rectus capitis posterior major and superior and inferior oblique muscles.

supraclavicular triangle  subclavian t.

suprameatal triangle  mastoid fossa.

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Hesselbach's triangle

n.

See inguinal triangle.

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Hesselbach's triangle,

See inguinal triangle.