| anterior belly of digastric muscle | <anatomy> The portion of the digastric muscle which extends anteriorly from the intermediate tendon, and attaches to the posterior aspect of the mandible. Synonym: venter anterior musculi digastrici. (05 Mar 2000) |
|---|---|
| anterior crural nerve | <anatomy, nerve> A nerve originating in the lumbar spinal cord (usually l2 to l4) and traveling through the lumbar plexus to provide motor innervation to extensors of the thigh and sensory innervation to parts of the thigh, lower leg, and foot, and to the hip and knee joints. (12 Dec 1998) |
| anterior cutaneous branch of iliohypogastric nerve | <anatomy, nerve> Distribution, skin on pubis. Synonym: ramus cutaneus anterior nervi iliohypogastrici, genital branch of iliohypogastric nerve. (05 Mar 2000) |
| anterior ethmoidal nerve | <anatomy, nerve> A branch of the nasociliary nerve; passes through anterior ethmoidal foramen on superomedial wall of orbit into cranial cavity, giving rise to anterior meningeal nerves, then passes through cribriform plates into nasal cavity, supplying anterosuperior nasal mucosa. Synonym: nervus ethmoidalis anterior. (05 Mar 2000) |
| anterior interosseous nerve | <anatomy, nerve> A branch of the median arising in elbow region, running on interosseous membrane, supplying the flexor pollicis longus, part of flexor digitorum profundus and the pronator quadratus muscles, as well as radiocarpal and intercarpal joints. Synonym: nervus interosseus anterior, ramus profundus nervi radialis, nervus antebrachii anterior, anterior antebrachial nerve, volar interosseous nerve. (05 Mar 2000) |
| anterior rectus muscle of head | <anatomy, muscle> Origin, transverse process and lateral mass of atlas; insertion, basilar process of occipital bone; action, turns and inclines head forward; nerve supply, ventral primary ramus of first and second cervical spinal nerve. Synonym: musculus rectus capitis anterior, anterior rectus muscle of head, musculus rectus capitis anticus minor. (05 Mar 2000) |
| anterior scalene muscle | <anatomy, muscle> Origin, anterior tubercles of transverse processes of third to sixth cervical vertebrae; insertion, scalene tubercle of first rib; action, raises first rib; nerve supply, cervical plexus. Synonym: musculus scalenus anterior, anterior scalene muscle, musculus scalenus anticus. (05 Mar 2000) |
| anterior serratus muscle | <anatomy, muscle> Origin, from centre of lateral aspect of first eight to nine ribs; insertion, superior and inferior angles and intervening medial margin of scapula; action, rotates scapula and pulls it forward, elevates ribs; nerve supply, long thoracic from brachial plexus. Synonym: musculus serratus anterior, anterior serratus muscle, costoscapularis, musculus serratus magnus. (05 Mar 2000) |
| anterior superior alveolar branches of infraorbital nerve | <anatomy, nerve> The branches of the superior alveolar nerve that supply the incisors, canines, premolars, and first molar by their contributions to the superior dental plexus. Synonym: rami alveolares superiores anteriores nervi infraorbitalis. (05 Mar 2000) |
| anterior supraclavicular nerve | <anatomy, nerve> One of several nerves arising from the cervical plexus which supply the skin over the upper medial part of the thorax. Synonym: nervus supraclavicularis medialis, anterior supraclavicular nerve. (05 Mar 2000) |
| anterior tibial muscle | <anatomy, muscle> Origin, upper two-thirds of lateral surface of tibia, interosseous membrane, and intermuscular septum; insertion, medial cuneiform and base of first metatarsal; action, dorsiflexion and inversion of foot; nerve supply, deep peroneal. Synonym: musculus tibialis anterior, anterior tibial muscle, musculus tibialis anticus. (05 Mar 2000) |
| anterior tibial nerve | <anatomy, nerve> One of the terminal branches of the common peroneal nerve, arising at the fibular neck and passing into the anterior compartment of the leg; it supplies the tibialis anterior, extensor hallucis longus, extensor digitorum longus, and peroneus tertius muscles in the leg, then crosses the ankle joint to supply the muscles on the dorsum of the foot (extensors hallucis and digitorum brevis) becoming cutaneous to innervate adjacent sides of the great and second toes. Synonym: nervus fibularis profundus, nervus peroneus profundus, anterior tibial nerve, deep fibular nerve. (05 Mar 2000) |
| antitragicus muscle | <anatomy> A band of transverse muscular fibres on the outer surface of the antitragus, arising from the border of the intertragic notch and inserted into the anthelix and cauda helicis. Synonym: musculus antitragicus, muscle of antitragus. (05 Mar 2000) |
| aortic nerve | <anatomy, nerve> A branch of the vagus which ends in the aortic arch and base of the heart; composed entirely of afferent fibres; its stimulation elicits a brainstem reflex which causes slowing of the heart, dilation of the peripheral vessels, and a fall in blood pressure. Synonym: Cyon's nerve, depressor nerve of Ludwig, Ludwig's nerve. (05 Mar 2000) |
| aponeurosis of external abdominal oblique muscle | <anatomy> Broad, flat tendinous portion of the external abdominal oblique muscle. The fleshy fibres of the muscle end in the aponeurosis along a line descending vertically from the costochondral joint of the ninth rib then turning laterally just below the level of the umbilicus toward the anterior superior iliac spine. The fibres of the aponeurosis run medially and inferiorly, contributing to the anterior wall of the sheath of the rectus abdominis muscle and decussating with those of the contralateral aponeurosis at the median linea alba. Inferomedially, the aponeurosis is attached to the upper border of the pubic symphysis, the pubic crest and pubic tubercle. Between the anterior superior iliac spine and the pubic tubercle, it is thickened and turned under, forming the inguinal ligaments. The portion of the aponeurosis attached to the pubic bone forms the superficial inguinal ring by splitting into medial and lateral crura. See: external spermatic fascia, inguinal ligament, lacunar ligament, pectineal ligament, reflected inguinal ligament, superficial inguinal ring, rectus sheath. (05 Mar 2000) |