muscle

muscle (mus´el)

A primary tissue, consisting predominantly of highly specialized contractile cells, which may be classified as skeletal m., cardiac m., or smooth m.; microscopically, the latter is lacking in transverse striations characteristic of the other two types; one of the contractile organs of the body by which movements of the various organs and parts are effected; typical m. is a mass of m. fibers (venter or belly), attached at each extremity, by means of a tendon, to a bone or other structure; the more proximal or more fixed attachment is called the origin, the more distal or more movable attachment is the insertion; the narrowing part of the belly that is attached to the tendon of origin is called the caput or head.For gross anatomical description, see musculusmusculus [NA]; [L. musculus]
m.'s of abdomen m.'s forming the wall of the abdomen including rectus abdominis, external and internal oblique m.'s, transversus abdominis, and quadratus abdominis.musculi abdominis [NA];
abdominal external oblique m. external oblique m
abdominal internal oblique m. internal oblique m
abductor digiti minimi m. of foot origin, lateral and medial processes of calcanean tuberosity; insertion, lateral side of proximal phalanx of fifth toe; action, abducts and flexes little toe; nerve supply, lateral plantar nerve.musculus abductor digiti minimi pedis [NA], abductor m. of little toe, musculus abductor digiti quinti (2);
abductor digiti minimi m. of hand origin, pisiform bone and pisohamate ligament; insertion, medial side of base of proximal phalanx of the little finger; action, abducts and flexes little finger; nerve supply, ulnar.musculus abductor digiti minimi manus [NA], abductor m. of little finger, musculus abductor digiti quinti (1);
abductor m. of great toe abductor hallucis m
abductor hallucis m. origin, medial process of calcaneal tuberosity, flexor retinaculum, and plantar aponeurosis; insertion, medial side of proximal phalanx of great toe; action, abducts great toe; nerve supply, medial plantar.musculus abductor hallucis [NA], abductor m. of great toe;
abductor m. of little finger abductor digiti minimi m. of hand
abductor m. of little toe abductor digiti minimi m. of foot
abductor pollicis brevis m. origin, tubercle of trapezium and flexor retinaculum; insertion, lateral side of proximal phalanx of thumb; action, abducts thumb; nerve supply, median.musculus abductor pollicis brevis [NA], short abductor m. of thumb;
abductor pollicis longus m. origin, interosseous membrane and posterior surfaces of radius and ulna; insertion, lateral side of base of first metacarpal bone; action, abducts and assists in extending thumb; nerve supply, radial.musculus abductor pollicis longus [NA], long abductor m. of thumb, musculus extensor ossis metacarpi pollicis;
accessory flexor m. of foot quadratus plantae m
adductor brevis m. origin, superior ramus of pubis; insertion, upper third of medial lip of linea aspera; action, adducts thigh; nerve supply, obturator.musculus adductor brevis [NA], short adductor m;
adductor m. of great toe adductor hallucis m
adductor hallucis m. origin, by two heads, the transverse head from the capsules of the lateral four metatarsophalangeal joints and the oblique head from the lateral cuneiform and bases of the third and fourth metatarsal bones; insertion, lateral side of base of proximal phalanx of great toe; action, adducts great toe; nerve supply, lateral plantar.musculus adductor hallucis [NA], adductor m. of great toe;
adductor longus m. origin, symphysis and crest of pubis; insertion, middle third of medial lip of linea aspera; action, adducts thigh; nerve supply, obturator.musculus adductor longus [NA], long adductor m;
adductor magnus m. origin, ischial tuberosity and ischiopubic ramus; insertion, linea aspera and adductor tubercle of femur; action, adducts and extends thigh; nerve supply, obturator and sciatic.musculus adductor magnus [NA], great adductor m;
adductor minimus m. a small flat m. constituting the upper portion of the adductor magnus, insertion, the space above linea aspera.musculus adductor minimus;
adductor pollicis m. origin, by two heads, the transverse head from the shaft of the third metacarpal and the oblique head from the front of the base of the second metacarpal, the trapezoid and capitate bones; insertion, medial side of base of proximal phalanx of thumb; action, adducts thumb; nerve supply, ulnar.musculus adductor pollicis [NA], adductor m. of thumb;
adductor m. of thumb adductor pollicis m
Aeby's m. cutaneomucous m
Albinus' m. 1. risorius m 2. scalenus minimus m
anconeus m. origin, back of lateral condyle of humerus; insertion, olecranon process and posterior surface of ulna; action, extends forearm and abducts ulna in pronation of wrist; nerve supply, radial.musculus anconeus [NA], anconeus;
antagonistic m.'s those having an opposite function, the contraction of one having the potential, in theory, to "neutralize" that of the other.
anterior auricular m. origin, galea aponeurotica; insertion, cartilage of auricle; action, draws pinna of ear upward and forward; nerve supply, facial. Considered by some to be the anterior part of the temporoparietal m.musculus auricularis anterior [NA], musculus attrahens aurem, musculus attrahens auriculam, zygomaticoauricularis;
anterior cervical intertransversarii m.'s origin, anterior tubercle of cervical transverse process; insertion, anterior tubercle of next superior transverse process; action, abducts cervical vertebrae; nerve supply, ventral branch of cervical nerves.musculi intertransversarii anteriores cervicis [NA], anterior cervical intertransverse m.'s;
anterior cervical intertransverse m.'s anterior cervical intertransversarii m.'s
anterior rectus m. of head rectus capitis anterior m
anterior scalene m. scalenus anterior m
anterior serratus m. serratus anterior m
anterior tibial m. tibialis anterior m
antigravity m.'s the m.'s that maintain the posture characteristic of a given animal species. In most mammals they are the extensor m.'s.
antitragicus m. a band of transverse muscular fibers on the outer surface of the antitragus, arising from the border of the intertragic notch and inserted into the anthelix and cauda helicis.musculus antitragicus [NA], m. of antitragus;
m. of antitragus antitragicus m
appendicular m. one of the skeletal m.'s of the limbs.
arrector pili m.'s bundles of smooth m. fibers, attached to the deep part of the hair follicles, passing outward alongside the sebaceous glands to the papillary layer of the corium; they act to pull the hairs erect, causing "goose bumps" or "goose flesh" (cutis anserina).musculi arrectores pilorum [NA], arrectores pilorum, erector m.'s of hairs;
articular m. a m. that inserts directly onto the capsule of a joint, acting to retract the capsule in certain movements.musculus articularis [NA];
articular m. of elbow articularis cubiti m
articularis cubiti m. the name applied to a small slip of the medial head of the triceps that inserts into the capsule of the elbow joint.musculus articularis cubiti [NA], articular m. of elbow, subanconeus m;
articularis genu m. origin, lower fourth of anterior surface of shaft of femur; insertion, suprapatellar bursa of knee joint; action, retracts suprapatellar bursa, during extension of knee; nerve supply, femoral.musculus articularis genus [NA], articular m. of knee, Dupré's m., subcrural m., subcruralis, subcrureus, subquadricipital m;
articular m. of knee articularis genu m
aryepiglottic m. the fibers of the oblique arytenoid m. that extend from the summit of the arytenoid cartilage to the side of the epiglottis; action, constricts the laryngeal aperture.musculus aryepiglotticus [NA];
m.'s of auditory ossicles the m. stapedius and m. tensor tympani.musculi ossiculorum auditus [NA];
axial m. one of the skeletal m.'s of the trunk or head.
axillary arch m. pectorodorsalis mLanger's arch, Langer's m;
m.'s of the back the m.'s of the back in general, including those attaching the shoulder girdle to the trunk posteriorly, the posterior serratus m.'s, and the erector spinae.musculi dorsi [NA], dorsal m.'s;
Bell's m. a band of muscular fibers, forming a slight fold in the wall of the bladder, running from the uvula to the opening of the ureter on either side, bounding the trigonum.
biceps m. of arm biceps brachii m
biceps brachii m. origin, long head from supraglenoidal tuberosity of scapula, short head from coracoid process; insertion, tuberosity of radius; action, flexes and supinates forearm (it is the primary supinator of the forearm); nerve supply, musculocutaneous.musculus biceps brachii [NA], biceps m. of arm;
biceps femoris m. origin, long head (caput longum) from tuberosity of ischium, short head (caput breve) from lower half of lateral lip of linea aspera; insertion, head of fibula; action, flexes knee and rotates leg laterally; nerve supply, long head, tibial, short head, peroneal.musculus biceps femoris [NA], biceps m. of thigh, musculus biceps flexor cruris;
biceps m. of thigh biceps femoris m
bipennate m. a muscle with a central tendon toward which the fibers converge on either side like the barbs of a feather.musculus bipennatus [NA];
Bochdalek's m. musculus triticeoglossus
Bovero's m. cutaneomucous m
Bowman's m. ciliary m
brachial m. brachialis m
brachialis m. origin, lower two-thirds of anterior surface of humerus; insertion, coronoid process of ulna; action, flexes elbow; nerve supply, musculocutaneous, usually with a minor contribution from the radial.musculus brachialis [NA], brachial m;
brachiocephalic m. musculus brachiocephalicus
brachioradial m. brachioradialis m
brachioradialis m. origin, lateral supracondylar ridge of humerus; insertion, front of base of styloid process of radius; action, flexes elbow and assists slightly in supination; nerve supply, (common) radial.musculus brachioradialis [NA], brachioradial m;
branchiomeric m.'s the m.'s derived from branchial arch mesoderm that provide a large portion of the musculature for the face and neck.
Braune's m. puborectalis m
broadest m. of back latissimus dorsi m
bronchoesophageal m. muscular fascicles, arising from the wall of the left bronchus, which reinforce the musculature of the esophagus.musculus bronchoesophageus [NA];
Brücke's m. the part of the ciliary m. formed by the meridional fibers.Crampton's m;
buccinator m. origin, posterior portion of alveolar portion of maxilla and mandible and pterygomandibular raphe; insertion, orbicularis oris at angle of mouth; action, flattens cheek, retracts angle of mouth; nerve supply, facial. Plays an important role in mastication, working with tongue to keep food between teeth; when it is paralyzed, food accumulates in the oral vestibule.musculus buccinator [NA], cheek m;
bulbocavernosus m. in the male: origin, the perineal membrane fascia on the dorsum of the bulb of the penis; insertion, central tendon of the perineum and the median raphe on the free surface of the bulb; action, constricts bulbous urethra when attempting to expel last drops following urination, or spasmodically with ejaculation to expel semen. In the female: origin, the dorsum of the clitoris, the corpus cavernosum, and the perineal membrane; insertion, central tendon of the perineum; action, acts as a weak sphincter of the vagina; when developed, is a part of "cross-member musculature" of pelvic floor which resists prolapse of pelvic viscera. Nerve supply, pudendal (deep perineal branch).musculus bulbospongiosus [NA], musculus bulbocavernosus, musculus ejaculator seminis, musculus sphincter vaginae (1), sphincter vaginae (1);
cardiac m. the m. comprising the myocardium, consisting of anastomosing transversely striated m. fibers formed of cells united at intercalated disks; the one or two nuclei of each cell are centrally located and the longitudinally arranged myofibrils have considerable sarcoplasm around them; connective tissue is limited to reticular and fine collagenous fibers.m. of heart;
Casser's perforated m. coracobrachialis m
ceratocricoid m. a fasciculus from the posterior cricoarytenoid m. inserted into the inferior horn of the thyroid cartilage.musculus ceratocricoideus [NA], Merkel's m;
cervical iliocostal m. iliocostalis cervicis m
cervical interspinal m. cervical interspinales m.'s
cervical interspinales m.'s origin, tubercle of spinous process of cervical vertebra; insertion, tubercle of spinous process of next superior vertebra; action, extends the neck; nerve supply, dorsal rami of cervical nerves.musculus interspinalis cervicis [NA], cervical interspinal m;
cervical longissimus m. longissimus cervicis m
cervical rotator m.'s rotatores cervicis m.'s
cheek m. buccinator m
chin m. mentalis m
chondroglossus m. muscular fibers from lesser horn of hyoid bone occasionally separated from the hyoglossus, but usually forming part of it.musculus chondroglossus [NA], ceratoglossus, keratoglossus;
ciliary m. the smooth m. of the ciliary body; it consists of circular fibers (Müller's m.) and radiating fibers (meridional fibers, or Brücke's m.); action, in contracting, its diameter is reduced (like a sphincter), reducing tensile (stretching) forces on lens, allowing it to thicken for near vision (accommodation).musculus ciliaris [NA], Bowman's m., ciliary ligament;
coccygeal m. coccygeus m
coccygeus m. origin, spine of ischium and sacrospinous ligament; insertion, sides of lower part of sacrum and upper part of coccyx; action, assists in support of pelvic floor, especially when intra-abdominal pressures increase; nerve supply, third and fourth sacral.musculus coccygeus [NA], coccygeal m., musculus ischiococcygeus;
m.'s of coccyx the m.'s of the coccyx considered as a group, including the musculus coccygeus and the inconstant ventral and dorsal sacrococcygeal m.'s.musculi coccygei [NA];
Coiter's m. corrugator supercilii m
compressor m. of lips cutaneomucous m
coracobrachial m. coracobrachialis m
coracobrachialis m. origin, coracoid process of scapula; insertion, middle of medial border of humerus; action, adducts and flexes the arm; resists downward dislocation of shoulder joint; nerve supply, musculocutaneous.musculus coracobrachialis [NA], Casser's perforated m., coracobrachial m;
corrugator m. corrugator supercilii m
corrugator cutis m. of anus smooth muscle fibers radiating from the anal opening superficial to the external sphincter.musculus corrugator cutis ani;
corrugator supercilii m. origin, from orbital portion of m. orbicularis oculi and nasal prominence; insertion, skin of eyebrow; action, draws medial end of eyebrow downward and wrinkles forehead vertically; nerve supply, facial.musculus corrugator supercilii [NA], Coiter's m., corrugator m., wrinkler m. of eyebrow;
cowl m. trapezius m
Crampton's m. Brücke's m
cremaster m. origin, from internal oblique m. and inguinal ligament; insertion, cremasteric fascia (spermatic cord); action, raises testicle; nerve supply, genital branch of genitofemoral; in the male the muscle envelops the spermatic cord and testis, in the female, the round ligament of the uterus.musculus cremaster [NA], Riolan's m. (2);
cricopharyngeus m. inferior constrictor m. of pharynxsuperior esophageal sphincter;
cricothyroid m. origin, anterior surface of arch of cricoid; insertion, the anterior or straight part passes upward to ala of thyroid; the posterior or oblique part passes more outward to inferior horn of thyroid; action, makes vocal folds tense increasing the pitch of voice tone; nerve supply, external laryngeal branch of superior laryngeal nerve (from vagus).musculus cricothyroideus [NA];
cruciate m. a general type of m. in which the m.'s or bundles of m. fibers cross in an X-shaped configuration; e.g., the oblique arytenoid m.'s.musculus cruciatus [NA];
cutaneomucous m. the "sucking m.," a labial m. formed by sagittal fibers running from the skin to the mucous membrane.Aeby's m., Bovero's m., compressor m. of lips, Klein's m., Krause's m., mucocutaneous m., musculus cutaneomucosus;
cutaneous m. a m. that lies in the subcutaneous tissue and attaches to the skin; it may or may not have a bony attachment. The m.'s of expression are the chief examples of cutaneous m.'s in the human.musculus cutaneus [NA];
dartos m. dartos fascia
deep m.'s of back m.'s of the back innervated by the dorsal primary rami of spinal nerves; includes erector spinae, transversospinalis, interspinal, and intertransverse m.'s; excludes the superficial back m.'s which are appendicular and are innervated by ventral rami, and the trapezius, innervated by the spinal accessory nerve.true m.'s of back;
deep flexor m. of fingers flexor digitorum profundus m
deep transverse perineal m. origin, ramus of ischium; insertion, with its fellow in a median raphe; action, assists sphincter urethrae with some sphincteric action on vagina in female; nerve supply, pudendal (dorsal nerve of penis/clitoris).musculus transversus perinei profundus [NA], deep transverse m. of perineum, musculus sphincter vaginae (2), sphincter vaginae (2);
deep transverse m. of perineum deep transverse perineal m
deltoid m. origin, lateral third of clavicle, lateral border of acromion process, lower border of spine of scapula; insertion, lateral side of shaft of humerus a little above its middle (deltoid tuberosity); action, abduction, flexion, extension, and rotation of arm; nerve supply, axillary from fifth and sixth cervical spinal cord segments through brachial plexus.musculus deltoideus [NA], deltoid (2);
depressor anguli oris m. origin, lower border of mandible anteriorly; insertion, blends with other m.'s in lower lip near angle of mouth; action, pulls down corners of mouth; nerve supply, facial.musculus depressor anguli oris [NA], musculus triangularis labii inferioris, musculus triangularis (2), triangular m. (2);
depressor m. of epiglottis thyroepiglottic m
depressor m. of eyebrow depressor supercilii m
depressor labii inferioris m. origin, anterior portion of lower border of mandible; insertion, orbicularis oris m. and skin of lower lip; action, depresses lower lip; nerve supply, facial.musculus depressor labii inferioris [NA], depressor m. of lower lip, musculus quadratus labii inferioris, musculus quadratus menti;
depressor m. of lower lip depressor labii inferioris m
depressor septi m. a vertical fasciculus from the orbicularis oris m. passing upward along the median line of the upper lip, and inserted into the cartilaginous septum of the nose; action, depresses septum; nerve supply, facial.musculus depressor septi [NA], depressor m. of septum;
depressor m. of septum depressor septi m
depressor supercilii m. fibers of the orbital part of the orbicularis oculi m. insert in the eyebrow; action, depresses eyebrow; nerve supply, facial.musculus depressor supercilii [NA], depressor m. of eyebrow;
detrusor m. of urinary bladder the muscular coat of the bladder.musculus detrusor urinae;
digastric m. 1. one of the suprahyoid group of m.'s consisting of two bellies united by a central tendon which is connected to the body of the hyoid bone; origin, by posterior belly from the digastric groove medial to the mastoid process; insertion, by anterior belly into lower border of mandible near midline; action, elevates the hyoid when mandible is fixed; depresses the mandible when hyoid is fixed; nerve supply, posterior belly from facial, anterior belly by nerve to the mylohyoid from the mandibular division of trigeminal; 2. a m. with two fleshy bellies separated by a fibrous insertion;musculus digastricus [NA], biventer mandibulae, musculus biventer mandibulae, two-bellied m;
dilator m. a m. which opens an orifice or dilates the lumen of an organ; it is the dilating or opening component of a pylorus (the other component is the sphincter m.).musculus dilatator, musculus dilator;
dilator m. of ileocecal sphincter the longitudinal muscular fibers that open the ileal orifice at the level of the cecocolic junction.musculus dilator pylori ilealis;
dilator pupillae m. the radial muscular fibers extending from the sphincter pupillae to the ciliary margin; some anatomists regard them as elastic, not muscular, in humans.musculus dilator pupillae [NA], dilator iridis, dilator of pupil, musculus dilator iridis;
dilator m. of pylorus the longitudinal muscular fibers that open the gastroduodenal junction.musculus dilator pylori gastroduodenalis;
dorsal m.'s m.'s of the back
dorsal interosseous m.'s of foot four muscles in the foot; origin, from sides of adjacent metatarsal bones; insertion, first into medial, second into lateral side of proximal phalanx of second toe, third and fourth into lateral side of proximal phalanx of third and fourth toes; action, abduct toes 2-4 from an axis through the second toe; nerve supply, lateral plantar.musculi interossei dorsalis pedis [NA];
dorsal interosseous m.'s of hand four muscles in the hand; origin, sides of adjacent metacarpal bones; insertion, proximal phalanges and extensor expansion, first on radial side of index, second on radial side of middle finger, third on ulnar side of middle finger, fourth on ulnar side of ring finger; action, abduct fingers 2-4 from the axis of the middle finger, nerve supply, ulnar.musculi interossei dorsalis manus [NA];
dorsal sacrococcygeal m. dorsal sacrococcygeus m
dorsal sacrococcygeus m. an inconstant and poorly developed muscle on the dorsal surfaces of the sacrum and coccyx, the remains of a portion of the tail musculature of lower animals.musculus sacrococcygeus dorsalis [NA], dorsal sacrococcygeal m., musculus extensor coccygis, musculus sacrococcygeus posterior;
Dupré's m. articularis genu m
Duverney's m. lacrimal part of orbicularis oculi muscle See orbicularis oculi m.
elevator m. of anus levator ani m
elevator m. of prostate levator prostatae m
elevator m. of rib levatores costarum m.'s
elevator m. of scapula levator scapulae m
elevator m. of soft palate levator veli palatini m
elevator m. of thyroid gland levator m. of thyroid gland
elevator m. of upper eyelid levator palpebrae superioris m
elevator m. of upper lip levator labii superioris m
elevator m. of upper lip and wing of nose levator labii superioris alaeque nasi m
epicranial m. epicranius m
epicranius m. composed of the epicranial aponeurosis and the m.'s inserting into it, i.e., the occipitofrontalis m. and temporoparietalis m.musculus epicranius [NA], epicranial m., scalp m;
erector m.'s of hairs arrector pili m.'s
erector spinae m.'s origin, from sacrum, ilium, and spines of lumbar vertebrae; it divides into three columns, iliocostalis m., longissimus m., and spinalis m., which insert into ribs and vertebrae with additional muscle slips joining the columns at successively higher levels; action, extends vertebral column; nerve supply, dorsal primary rami of spinal nerves.musculus erector spinae [NA], erector m. of spine, musculus sacrospinalis;
erector m. of spine erector spinae m.'s
extensor carpi radialis brevis m. origin, lateral epicondyle of humerus; insertion, base of third metacarpal bone; action, extends and abducts wrist radialward; nerve supply, radial.musculus extensor carpi radialis brevis [NA], short radial extensor m. of wrist;
extensor carpi radialis longus m. origin, lateral supracondylar ridge of humerus; insertion, back of base of second metacarpal bone; action, extends and deviates wrist radialward; nerve supply, radial.musculus extensor carpi radialis longus [NA], long radial extensor m. of wrist;
extensor carpi ulnaris m. origin, lateral epicondyle of humerus (humeral head) and oblique line and posterior border of ulna (ulnar head); insertion, base of fifth metacarpal bone; action, extends and abducts wrist ulnarward; nerve supply, radial (posterior interosseous).musculus extensor carpi ulnaris [NA], ulnar extensor m. of wrist;
extensor digiti minimi m. origin, lateral epicondyle of humerus; insertion, dorsum of proximal, middle, and distal phalanges of little finger; action, extends fingers; nerve supply, radial (posterior interosseous).musculus extensor digiti minimi [NA], extensor m. of little finger, musculus extensor digiti quinti proprius, musculus extensor minimi digiti;
extensor digitorum m. origin, lateral epicondyle of humerus; insertion, by four tendons into the base of the proximal and middle and base of the distal phalanges; action, extends fingers; nerve supply, radial (posterior interosseous).musculus extensor digitorum [NA], extensor m. of fingers, musculus extensor digitorum communis;
extensor digitorum brevis m. origin, dorsal surface of calcaneus; insertion, by four tendons fusing with those of the extensor digitorum longus, and by a slip attached independently to the base of the proximal phalanx of the great toe; action, extends toes; nerve supply, deep peroneal.musculus extensor digitorum brevis [NA], musculus extensor brevis digitorum, short extensor m. of toes;
extensor digitorum brevis m. of hand a short extensor muscle of the fingers of rare occurrence, and comparable to the short extensor of the toes.musculus extensor digitorum brevis manus, Pozzi's m;
extensor digitorum longus m. origin, lateral condyle of tibia, upper two-thirds of anterior margin of fibula; insertion, by four tendons to the dorsal surfaces of the bases of the proximal, middle, and distal phalanges of the second to fifth toes; action, extends the four lateral toes; nerve supply, deep branch of peroneal.musculus extensor digitorum longus [NA], long extensor m. of toes, musculus extensor longus digitorum;
extensor m. of fingers extensor digitorum m
extensor hallucis brevis m. the medial belly of extensor digitorum brevis m., the tendon of which is inserted into the base of the proximal phalanx of the great toe.musculus extensor hallucis brevis [NA], short extensor m. of great toe;
extensor hallucis longus m. origin, lateral surface of tibia and interosseous membrane; insertion, base of distal phalanx of great toe; action, extends the great toe; nerve supply, anterior tibial.musculus extensor hallucis longus [NA], long extensor m. of great toe;
extensor indicis m. origin, dorsal surface of ulna; insertion, dorsal extensor aponeurosis of index finger; action, assists in extending the forefinger; nerve supply, radial.musculus extensor indicis [NA], index extensor m., musculus extensor indicis proprius;
extensor m. of little finger extensor digiti minimi m
extensor pollicis brevis m. origin, dorsal surface of radius; insertion, base of proximal phalanx of thumb; action, extends and abducts the thumb; nerve supply, radial.musculus extensor pollicis brevis [NA], musculus extensor brevis pollicis, short extensor m. of thumb;
extensor pollicis longus m. origin, posterior surface of ulna; insertion, base of distal phalanx of thumb; action, extends distal phalanx of thumb; nerve supply, radial.musculus extensor pollicis longus [NA], long extensor m. of thumb, musculus extensor longus pollicis;
external intercostal m.'s each arises from lower border of one rib and pass obliquely downward and forward to be inserted into the upper border of rib below; action, contract during inspiration, also maintain tension in the intercostal spaces to resist mediolateral movement; nerve supply, intercostal.musculus intercostales externi [NA];
external oblique m. origin, fifth to twelfth ribs; insertion, anterior half of lateral lip of iliac crest, inguinal ligament, and anterior layer of the rectus sheath; action, diminishes capacity of abdomen, draws thorax downward; nerve supply, thoracoabdominal nerves.musculus obliquus externus abdominis [NA], abdominal external oblique m;
external obturator m. obturator externus m
external pterygoid m. lateral pterygoid m
external sphincter m. of anus external anal sphincter
extraocular m.'s the m.'s within the orbit including the four rectus muscles (superior, inferior, medial and lateral); two oblique muscles (superior and inferior), and the levator of the superior eyelid (levator palpebrae superioris).musculi bulbi [NA], m.'s of eyeball, ocular m.'s;
extrinsic m.'s m.'s arising outside of, but which act upon, the structure under consideration. For example, the m.'s operating the hand but having fleshy bellies located in the forearm.
m.'s of eyeball extraocular m.'s
facial m.'s m.'s of facial expression
m.'s of facial expression the numerous m.'s supplied by the facial nerve that are attached to and move the skin of the face. Nomina Anatomica also includes the buccinator m. in this group; even though it functions primarily in mastication.musculi faciales [NA], facial m.'s, mimetic m.'s;
femoral m. vastus intermedius m
fixator m. a m. that acts as a stabilizer of one part of the body during movement of another part.
flexor carpi radialis m. origin, common flexor origin of the medial condyle of humerus; insertion, anterior surface of the base of the second and most often sending a slip to that of the third metacarpal bone; action, flexes and abducts wrist radialward; nerve supply, median; its tendon travels in its own canal roofed by a layer of the transverse carpal ligament.musculus flexor carpi radialis [NA], radial flexor m. of wrist;
flexor carpi ulnaris m. origin, humeral head from medial condyle of humerus, ulnar head from olecranon and upper three-fifths of posterior border of ulna; insertion, pisiform bone, but is continued to the fifth metacarpal bone via the pisometacarpal ligament; action, flexes and abducts wrist ulnarward; nerve supply, ulnar.musculus flexor carpi ulnaris [NA], ulnar flexor m. of wrist;
flexor digiti minimi brevis m. of foot origin, base of metatarsal bone of the little toe and sheath of m. peroneus longus; insertion, lateral surface of base of proximal phalanx of little toe; action, flexes the proximal phalanx of the little toe; nerve supply, lateral plantar.musculus flexor digiti minimi brevis pedis [NA], short flexor m. of little toe;
flexor digiti minimi brevis m. of hand origin, hamulus of hamate bone; insertion, medial side of proximal phalanx of little finger; action, flexes proximal phalanx of little finger; nerve supply, ulnar.musculus flexor digiti minimi brevis manus [NA], short flexor m. of little finger;
flexor digitorum brevis m. origin, medial tubercle of calcaneus and central portion of plantar fascia; insertion, middle phalanges of four lateral toes by tendons perforated by those of the flexor longus; action, flexes lateral four toes; nerve supply, medial plantar.musculus flexor digitorum brevis [NA], musculus flexor brevis digitorum, short flexor m. of toes;
flexor digitorum longus m. origin, middle third of posterior surface of tibia; insertion, by four tendons, perforating those of the flexor brevis, into bases of distal phalanges of four lateral toes; action, flexes second to fifth toes; nerve supply, tibial nerve.musculus flexor digitorum longus [NA], long flexor m. of toes, musculus flexor longus digitorum;
flexor digitorum profundus m. origin, anterior surface of upper third of ulna; insertion, by four tendons, piercing those of the superficialis, into base of distal phalanx of each finger; action, flexes distal interphalangeal joint of fingers; nerve supply, ulnar and median (anterior interosseous muscle).musculus flexor digitorum profundus [NA], deep flexor m. of fingers, musculus flexor profundus;
flexor digitorum superficialis m. origin, humeroulnar head from the medial epicondyle of the humerus, the medial border of the coronoid process, and a tendinous arch between these points, radial head from the oblique line and middle third of the lateral border of the radius; insertion, by four split tendons, passing to either side of the profundus tendons, into sides of middle phalanx of each finger; action, flexes proximal interphalangeal joint of the fingers; nerve supply, median.musculus flexor digitorum superficialis [NA], musculus flexor digitorum sublimis, musculus flexor sublimis, superficial flexor m. of fingers;
flexor hallucis brevis m. origin, medial surface of cuboid and middle and lateral cuneiform bones; insertion, by two tendons, embracing that of the flexor longus hallucis, into the sides of the base of the proximal phalanx of the great toe; action, flexes great toe; nerve supply, medial and lateral plantar.musculus flexor hallucis brevis [NA], musculus flexor brevis hallucis, short flexor m. of great toe;
flexor hallucis longus m. origin, lower two-thirds of posterior surface of fibula; insertion, base of distal phalanx of great toe; action, flexes great toe; nerve supply, medial plantar.musculus flexor hallucis longus [NA], long flexor m. of great toe, musculus flexor longus hallucis;
flexor pollicis brevis m. origin, superficial portion from flexor retinaculum of wrist, deep portion from ulnar side of first metacarpal bone; insertion, base of proximal phalanx of thumb; action, flexes proximal phalanx of thumb; nerve supply, median (superficial head) and deep branch of ulnar (deep head). Some authors consider the deep head to be the first in a series of four palmar interossei muscles of the hand.musculus flexor pollicis brevis [NA], short flexor m. of thumb;
flexor pollicis longus m. origin, anterior surface of middle third of radius; insertion, distal phalanx of thumb; action, flexes distal phalanx of thumb; nerve supply, median palmar interosseous.musculus flexor pollicis longus [NA], long flexor m. of thumb, musculus flexor longus pollicis;
frontalis m. frontal belly of occipitofrontalis muscle
fusiform m. one that has a fleshy belly, tapering at either extremity.musculus fusiformis [NA], spindle-shaped m;
Gantzer's m. an accessory m. extending from the superficial flexor of the digits to the deep flexor of the digits.
gastrocnemius m. origin, by two heads (lateral and medial) from the lateral and medial condyles of the femur; insertion, with soleus by tendo calcaneus into lower half of posterior surface of calcaneus; action, plantar flexion of foot; nerve supply, tibial.musculus gastrocnemius [NA], gastrocnemius;
Gavard's m. oblique fibers in the muscular coat of the stomach.
genioglossal m. genioglossus m
genioglossus m. one of the paired lingual m.'s; origin, mental spine of the mandible; insertion, lingual fascia beneath the mucous membrane and epiglottis; action, depresses and protrudes the tongue; nerve supply, hypoglossal.musculus genioglossus [NA], genioglossal m., genioglossus, musculus geniohyoglossus;
geniohyoid m. origin, mental spine of mandible; insertion, body of hyoid bone; action, draws hyoid forward, or depresses jaw when hyoid is fixed; nerve supply, fibers from ventral primary rami of first and second cervical spinal nerves accompanying hypoglossal.musculus geniohyoideus [NA], geniohyoid, geniohyoideus;
gluteus maximus m. origin, ilium behind posterior gluteal line, posterior surface of sacrum and coccyx, and sacrotuberous ligament; insertion, iliotibial band of fascia lata (superficial three-quarters) and gluteal ridge (deep inferior one-quarter) of femur; action, extends thigh, especially from the flexed position, as in climbing stairs or rising from a sitting position; nerve supply, inferior gluteal.musculus gluteus maximus [NA];
gluteus medius m. origin, ilium between anterior and posterior gluteal lines; insertion, lateral surface of greater trochanter; action, abducts and rotates thigh; nerve supply, superior gluteal.musculus gluteus medius [NA], mesogluteus;
gluteus minimus m. origin, ilium between anterior and inferior gluteal lines; insertion, greater trochanter of femur; action, abducts thigh; nerve supply, superior gluteal.musculus gluteus minimus [NA];
gracilis m. origin, ramus of pubis near symphysis; insertion, shaft of tibia below medial tuberosity (see pes anserinus); action, adducts thigh, flexes knee, rotates leg medially; nerve supply, obturator.musculus gracilis [NA], gracilis (2);
great adductor m. adductor magnus m
greater pectoral m. pectoralis major m
greater posterior rectus m. of head rectus capitis posterior major m
greater psoas m. psoas major m
greater rhomboid m. rhomboideus major m
greater zygomatic m. zygomaticus major m
Guthrie's m. sphincter urethrae
hamstring m.'s the m.'s at the back of the thigh, comprising the long head of biceps, the semitendinosus, and the semimembranosus m.
m.'s of head the m.'s of expression, of mastication, and the suboccipital m.'s in general.musculi capitis [NA];
m. of heart cardiac m
helicis major m. a narrow band of muscular fibers on the anterior border of the helix of the auricle arising from the spine and inserted at the point where the helix becomes transverse.musculus helicis major [NA], large m. of helix;
helicis minor m. a band of oblique fibers covering the crus of the helix of the auricle.musculus helicis minor [NA], smaller m. of helix;
Horner's m. lacrimal part of orbicularis oculi muscle See orbicularis oculi m.
Houston's m. compressor venae dorsalis penis
hyoglossal m. hyoglossus m
hyoglossus m. origin, body and greater horn of hyoid bone; insertion, side of the tongue; action, retracts and pulls down side of tongue; nerve supply, motor by hypoglossal, sensory by lingual.musculus hyoglossus [NA], hyoglossal m., hyoglossus;
iliac m. iliacus m
iliacus m. origin, iliac fossa; insertion, tendon of psoas, anterior surface of lesser trochanter, and capsule of hip joint; action, flexes thigh and rotates it medially; nerve supply, lumbar plexus.musculus iliacus [NA], iliac m;
iliacus minor m. the fibers of the iliacus arising from the anterior inferior iliac spine and inserted into the iliofemoral ligament, sometimes distinctly separate from the rest of the muscle.musculus iliacus minor, musculus iliocapsularis;
iliococcygeal m. iliococcygeus m
iliococcygeus m. the posterior part of the levator ani arising from the tendinous arch of the levator ani muscle and inserting on the anococcygeal ligament and coccyx.musculus iliococcygeus [NA], iliococcygeal m;
iliocostal m. iliocostalis m
iliocostalis m. the lateral division of the erector spinae, having three subdivisions: iliocostalis lumborum m., iliocostalis thoracis m., and iliocostalis cervicis m.musculus iliocostalis [NA], iliocostal m;
iliocostalis cervicis m. origin, angles of upper six ribs; insertion, transverse processes of middle cervical vertebrae; action, extends, abducts, and rotates cervical vertebrae; nerve supply, dorsal branches of upper thoracic nerves.musculus iliocostalis cervicis [NA], cervical iliocostal m., cervicalis ascendens (1), musculus cervicalis ascendens;
iliocostalis lumborum m. origin, with erector spinae; insertion, the angles of lower six ribs; action, extends, abducts, and rotates lumbar vertebrae; nerve supply, dorsal branches of thoracic and lumbar nerves.musculus iliocostalis lumborum [NA], lumbar iliocostal m., musculus sacrolumbalis;
iliocostalis thoracis m. origin, medial side of angles of lower six ribs; insertion, angles of upper six ribs; action, extends, abducts, and rotates thoracic vertebrae; nerve supply, dorsal branches of thoracic nerves.musculus iliocostalis thoracis [NA], musculus iliocostalis dorsi;
iliopsoas m. a compound muscle, consisting of the iliacus m. and psoas major m.musculus iliopsoas [NA];
index extensor m. extensor indicis m
inferior constrictor m. of pharynx origin, outer surfaces of thyroid (thyropharyngeal part) and cricoid (cricopharyngeal part, musculus cricopharyngeus; superior or upper esophageal sphincter m.) cartilages; insertion, pharyngeal raphe in the posterior portion of wall of pharynx; action, narrows lower part of pharynx in swallowing, the cricopharyngeal part has a sphincteric function for the esophagus, allowing some voluntary control of eructation and reflux; nerve supply, pharyngeal plexus.musculus constrictor pharyngis inferior [NA], cricopharyngeus m., laryngopharyngeus, musculus laryngopharyngeus;
inferior gemellus m. origin, tuberosity of ischium; insertion, tendon of m. obturator internus; action, rotates thigh laterally; nerve supply, sacral plexus.musculus gemellus inferior [NA], gemellus;
inferior lingual m. inferior longitudinal m. of tongue
inferior longitudinal m. of tongue an intrinsic m. of the tongue, cylindrical in shape, occupying the underpart on either side; action, shortens the lower part of the tongue; nerve supply, motor by hypoglossal, sensory by lingual.musculus longitudinalis inferior [NA], inferior lingual m;
inferior oblique m. origin, orbital plate of maxilla lateral to the lacrimal groove; insertion, sclera between the superior and lateral recti; action, primary, extorsion; secondary, elevation and abduction; nerve supply, oculomotor (inferior branch).musculus obliquus inferior [NA];
inferior oblique m. of head obliquus capitis inferior m
inferior posterior serratus m. serratus posterior inferior m
inferior rectus m. origin, inferior part of the common tendinous ring; insertion, inferior part of sclera of the eye; action, primary, depression; secondary, adduction and extorsion; nerve supply, oculomotor (inferior branch).musculus rectus inferior [NA];
inferior tarsal m. poorly developed smooth m. in the lower eyelid that acts to widen the palpebral fissure.musculus tarsalis inferior [NA];
infrahyoid m.'s the small, flat m.'s inferior to the hyoid bone including the sternohyoid, omohyoid, sternothyroid, thyrohyoid, and levator m. of the thyroid gland.musculi infrahyoidei [NA], strap m.'s;
infraspinatus m. origin, infraspinous fossa of scapula; insertion, middle facet of greater tubercle of humerus; action, extends arm and rotates it laterally; nerve supply, suprascapular (from fifth to sixth cervical spinal nerves).musculus infraspinatus [NA];
innermost intercostal m. a layer parallel to and essentially part of the internal intercostal m. but separated from it by the intercostal vessels and nerves. See also entries underinternal intercostal muscle for attachment, action and nerve supplymusculus intercostalis intimus [NA];
intermediate great m. vastus intermedius m
intermediate layer of the transversospinalis m.'s multifidus m
intermediate vastus m. vastus intermedius m
internal intercostal m. each arises from lower border of rib and passes obliquely downward and backward to be inserted into upper border of rib below; action, contract during expiration, also maintain tension in the intercostal spaces to resist mediolateral movement; nerve supply, intercostal.musculus intercostalis internus [NA];
internal oblique m. origin, iliac fascia deep to lateral part of inguinal ligament, anterior half of crest of ilium, and lumbar fascia; insertion, tenth to twelfth ribs and sheath of rectus; some of the fibers from inguinal ligament terminate in the conjoint tendon; action, diminishes capacity of abdomen, flexes lumbar vertebral column (bends thorax forward); nerve supply, lower thoracic.musculus obliquus internus abdominis [NA], abdominal internal oblique m;
internal obturator m. obturator internus m
internal pterygoid m. medial pterygoid m
internal sphincter m. of anus internal anal sphincter
interosseous m.'s m.'s which arise from and run between the long (metacarpal and metatarsal) bones of the hand and foot, extending to and producing movement of the digits. See also dorsal interosseous m.'s of foot, dorsal interosseous m.'s of hand, palmar interosseous m., plantar interosseous m.musculi interossei [NA];
interspinal m.'s interspinales m.'s
interspinales m.'s the paired m.'s between spinous processes of adjacent vertebrae; subdivided into cervical, thoracic, and lumbar m.'s.musculi interspinales [NA], interspinal m.'s;
intertransverse m.'s intertransversarii m.'s
intertransversarii m.'s the paired m.'s between transverse processes of adjacent vertebrae; there are anterior and posterior m.'s in the cervical region; lateral and medial m.'s in the lumbar region; and single m.'s in the thoracic region.musculi intertransversarii [NA], intertransverse m.'s;
intrinsic m.'s m.'s fully contained (origin, belly, and insertion) within the structure under consideration. For example, the interossei and lumbrical m.'s are intrinsic m.'s of the hand.
intrinsic m.'s of foot m.'s fully contained (origin, belly, insertion) in the foot and toes. These m.'s are arranged in four layers and all are innervated by the plantar branches of the tibial nerve. Although they may be capable of producing the actions described under their individual entries, as a group the primary function of the intrinsic m.'s of the foot is to provide dynamic support of the longitudinal arch of the foot, resisting the forces which act momentarily to spread the arch during walking and running.
involuntary m.'s m.'s not ordinarily under control of the will; except in the case of the heart, they are smooth (nonstriated) m.'s, innervated by the autonomic nervous system.
ischiocavernous m. origin, ramus of ischium; insertion, corpus cavernosum penis (or clitoridis); action, compresses the crus of the penis (or clitoris) forcing blood in its sinuses into the distal part of the corpus cavernosum; nerve supply, perineal.musculus ischiocavernosus [NA], musculus erector clitoridis, musculus erector penis;
Jung's m. pyramidal auricular m
Klein's m. cutaneomucous m
Kohlrausch's m. the longitudinal m.'s of the rectal wall.
Krause's m. cutaneomucous m
Landström's m. microscopic m. fibers in the fascia behind and about the eyeball, attached anteriorly to the lids and anterior orbital fascia; its action is to draw the eyeball forward and the lids backward, resisting the pull of the four orbital m.'s.
Langer's m. axillary arch m
large m. of helix helicis major m
m.'s of larynx the intrinsic m.'s that regulate the length, position and tension of the vocal cords and adjust the size of the openings between the aryepiglottic folds, the ventricular folds and the vocal folds.musculi laryngis [NA];
lateral cricoarytenoid m. origin, upper margin of arch of cricoid cartilage; insertion, muscular process of arytenoid; action, adducts vocal folds (narrows rima glottidis); nerve supply, recurrent laryngeal.musculus cricoarytenoideus lateralis [NA];
lateral great m. vastus lateralis m
lateral lumbar intertransversarii m.'s origin, transverse processes of lumbar vertebrae; insertion, next superior transverse process; action, abducts lumbar vertebrae; nerve supply, ventral branches of lumbar nerves.musculi intertransversarii laterales lumborum [NA], lateral lumbar intertransverse m.'s;
lateral lumbar intertransverse m.'s lateral lumbar intertransversarii m.'s
lateral pterygoid m. origin, inferior head from lateral lamina of pterygoid process; superior head from infratemporal crest and adjacent greater wing of the sphenoid; insertion, into pterygoid pit of mandible and articular disk; action, brings jaw forward, opens jaw; nerve supply, nerve to lateral pterygoid from mandibular division of trigeminal.musculus pterygoideus lateralis [NA], external pterygoid m., musculus pterygoideus externus;
lateral rectus m. origin, lateral part of the common tendinous ring that bridges superior orbital fissure; insertion, lateral part of sclera of eye; action, abduction; nerve supply, abducens.musculus rectus lateralis [NA], abducens oculi, musculus rectus externus;
lateral rectus m. of the head rectus capitis lateralis m
lateral vastus m. vastus lateralis m
latissimus dorsi m. origin, spinous processes of lower five or six thoracic and the lumbar vertebrae, median ridge of sacrum, and outer lip of iliac crest; insertion, with teres major into posterior lip of bicipital groove of humerus; action, adducts arm, rotates it medially, and extends it; nerve supply, thoracodorsal.musculus latissimus dorsi [NA], broadest m. of back;
lesser rhomboid m. rhomboid minor m
lesser zygomatic m. zygomaticus minor m
levator anguli oris m. origin, canine fossa of maxilla; insertion, orbicularis oris and skin at angle of mouth; action, raises angle of mouth; nerve supply, facial.musculus levator anguli oris [NA], musculus caninus, musculus triangularis labii superioris;
levator ani m. formed by pubococcygeus and iliococcygeus m.'s; origin, posterior body of pubis, tendinous arch of the levator ani, and spine of ischium; insertion, anococcygeal ligament, sides of the lower part of the sacrum and of coccyx; action, resists prolapsing forces and draws the anus upward following defecation; supports the pelvic viscera; nerve supply, nerve to levator ani (fourth sacral spinal nerve).musculus levator ani [NA], elevator m. of anus;
levatores costarum m.'s musculus levator costae [NA], elevator m. of rib, musculi levatores costarum; See long levatores costarum m.'s, short levatores costarum m.'s.
levator labii superioris m. origin, maxilla below infraorbital foramen; insertion, orbicularis oris of upper lip; action, elevates upper lip; nerve supply, facial.musculus levator labii superioris [NA], caput infraorbitale quadrati labii superioris, elevator m. of upper lip;
levator labii superioris alaeque nasi m. origin, root of nasal process of maxilla; insertion, wing of nose and orbicularis oris m. of upper lip; action, elevates upper lip and wing of nose; nerve supply, facial.musculus levator labii superioris alaeque nasi [NA], caput angulare quadrati labii superioris, elevator m. of upper lip and wing of nose;
levator palati m. levator veli palatini m
levator palpebrae superioris m. origin, orbital surface of the lesser wing of the sphenoid, above and anterior to the optic canal; insertion, skin of eyelid, tarsal plate, and orbital walls, by medial and lateral expansions of the aponeurosis of insertion; action, raises the upper eyelid; nerve supply, oculomotor.musculus levator palpebrae superioris [NA], elevator m. of upper eyelid, musculus orbitopalpebralis, palpebralis;
levator prostatae m. in the male, the most medial fibers of the levator ani (pubococcygeus) m. that extend from the pubis into the fascia of the prostate.musculus levator prostatae [NA], elevator m. of prostate;
levator scapulae m. origin, from posterior tubercles of transverse processes of four upper cervical vertebrae; insertion, into superior angle of scapula; action, raises the scapula; nerve supply, dorsal scapular nerve.musculus levator scapulae [NA], elevator m. of scapula, musculus levator anguli scapulae;
levator m. of thyroid gland a fasciculus occasionally passing from the thyrohyoid m. to the isthmus of the thyroid gland.musculus levator glandulae thyroideae [NA], elevator m. of thyroid gland, Soemmerring's m;
levator veli palatini m. origin, apex of petrous portion of temporal bone and lower part of cartilaginous auditory (eustachian) tube; insertion, aponeurosis of soft palate; action, raises soft palate; through the expansion of its fleshy belly during contraction, it helps to "push" open the auditory tube; nerve supply, pharyngeal plexus (cranial root of accessory nerve).musculus levator veli palatini [NA], elevator m. of soft palate, levator palati m., musculus levator palati, musculus petrostaphylinus;
long abductor m. of thumb abductor pollicis longus m
long adductor m. adductor longus m
long extensor m. of great toe extensor hallucis longus m
long extensor m. of thumb extensor pollicis longus m
long extensor m. of toes extensor digitorum longus m
long fibular m. peroneus longus m
long flexor m. of great toe flexor hallucis longus m
long flexor m. of thumb flexor pollicis longus m
long flexor m. of toes flexor digitorum longus m
long m. of head longus capitis m
longissimus m. the intermediate division of the erector spinae m. having three subdivisions: longissimus capitis m., longissimus cervicis m., and longissimus thoracis m.musculus longissimus [NA];
longissimus capitis m. origin, from transverse processes of upper thoracic and transverse and articular processes of lower and middle cervical vertebrae; insertion, into mastoid process; action, keeps head erect, draws it backward or to one side; nerve supply, dorsal primary rami of cervical spinal nerves.musculus longissimus capitis [NA], musculus complexus minor, musculus trachelomastoideus, musculus transversalis capitis;
longissimus cervicis m. origin, transverse processes of upper thoracic vertebrae; insertion, transverse processes of middle and upper cervical vertebrae; action, extends cervical vertebrae; nerve supply, dorsal primary rami of lower cervical and upper thoracic spinal nerves.musculus longissimus cervicis [NA], cervical longissimus m., musculus transversalis cervicis, musculus transversalis colli;
longissimus thoracis m. origin, with iliocostalis and from transverse processes of lower thoracic vertebrae; insertion, by lateral slips into most or all of the ribs between angles and tubercles and into tips of transverse processes of upper lumbar vertebrae, and by medial slips into accessory processes of upper lumbar and transverse processes of thoracic vertebrae; action, extends vertebral column; nerve supply, dorsal primary rami of thoracic and lumbar spinal nerves.musculus longissimus thoracis [NA], musculus longissimus dorsi, thoracic longissimus m;
long levatores costarum m.'s insertion, the second rib below their origin; action, raise ribs; nerve supply, intercostal.musculi levatores costarum longi;
long m. of neck longus colli m
long palmar m. palmaris longus m
long peroneal m. peroneus longus m
long radial extensor m. of wrist extensor carpi radialis longus m
longus capitis m. origin, anterior tubercles of transverse processes of third to sixth cervical vertebrae; insertion, basilar process of occipital bone; action, twists or flexes neck anteriorly; nerve supply, cervical plexus.musculus longus capitis [NA], long m. of head, musculus rectus capitis anticus major;
longus colli m. medial part: origin, the bodies of the third thoracic to the fifth cervical vertebrae; insertion, the bodies of the second to fourth cervical vertebrae; superolateral part: origin, the anterior tubercles of the transverse processes of the third to fifth cervical vertebrae; insertion, the anterior tubercle of the atlas; inferolateral part: origin, the bodies of the first to third thoracic vertebrae; insertion, the anterior tubercles of the transverse processes of the fifth and sixth cervical vertebrae; action, for all three parts, twist neck and flex neck anteriorly; nerve supply, for all three parts, ventral primary rami of cervical spinal nerves (cervical plexus).musculus longus colli [NA], long m. of neck;
lumbar iliocostal m. iliocostalis lumborum m
lumbar interspinal m. lumbar interspinales m.'s
lumbar interspinales m.'s origin, superior margin of lumbar spinous process; insertion, inferior margin of next superior spinous process; action, extends lumbar vertebrae; nerve supply, dorsal primary rami of lumbar spinal nerves.musculus interspinalis lumborum [NA], lumbar interspinal m;
lumbar quadrate m. quadratus lumborum m
lumbar rotator m.'s rotatores lumborum m.'s
lumbrical m. of foot four intrinsic m.'s of the foot; origin, first: from tibial side of tendon to second toe of flexor digitorum longus; second, third, and fourth: from adjacent sides of all four tendons of this m.; insertion, tibial side of extensor tendon on dorsum of each of the four lateral toes; action, flex the proximal and extend the middle and distal phalanges; nerve supply, lateral (second to fourth lumbricals) and medial (first lumbrical) plantar.musculus lumbricalis pedis [NA];
lumbrical m. of hand four intrinsic muscles of the hand; origin, the two lateral: from the radial side of the tendons of the flexor digitorum profundus going to the index and middle fingers; the two medial: from the adjacent sides of the second and third, and third and fourth tendons; insertion, radial side of extensor tendon on dorsum of each of the four fingers; action, flexes metacarpophalangeal joint and extends the proximal and distal interphalangeal joint; nerve supply, the two radial m.'s by the median, the two ulnar m.'s by the ulnar.musculus lumbricalis manus [NA];
Marcacci's m. a sheet of smooth m. fibers underlying the areola and nipple of the mammary gland.
masseter m. origin, superficial part: inferior border of the anterior two-thirds of the zygomatic arch; deep part: inferior border and medial surface of the zygomatic arch; insertion, lateral surface of ramus and coronoid process of the mandible; action, elevates mandible (closes jaw); nerve supply, masseteric branch of mandibular division of trigeminal.musculus masseter [NA];
m.'s of mastication m.'s derived from the first (mandibular) arch used in chewing; all receive innervation from the motor root of the trigeminal nerve via its mandibular division. See masseter m., temporalis m., lateral pterygoid m., medial pterygoid m.
medial great m. vastus medialis m
medial lumbar intertransversarii m.'s origin, accessory and mamillary processes of lumbar vertebrae; insertion, corresponding processes of next superior vertebra; action, abducts lumbar vertebrae; nerve supply, dorsal primary rami of lumbar spinal nerves.musculi intertransversarii mediales lumborum [NA], medial lumbar intertransverse m.'s;
medial lumbar intertransverse m.'s medial lumbar intertransversarii m.'s
medial pterygoid m. origin, pterygoid fossa of sphenoid and tuberosity of maxilla; insertion, medial surface of mandible between angle and mylohyoid groove; action, elevates mandible closing jaw; nerve supply, nerve to medial pterygoid from mandibular division of trigeminal.musculus pterygoideus medialis [NA], internal pterygoid m., musculus pterygoideus internus;
medial rectus m. origin, medial part of the anulus tendineus communis; insertion, medial part of sclera of the eye; action, adduction; nerve supply, oculomotor.musculus rectus medialis [NA], musculus rectus internus;
medial vastus m. vastus medialis m
mentalis m. origin, incisor fossa of mandible; insertion, skin of chin; action, raises and wrinkles skin of chin, thus elevating the lower lip; nerve supply, facial.musculus mentalis [NA], chin m., musculus levator labii inferioris;
Merkel's m. ceratocricoid m
middle constrictor m. of pharynx origin, stylohyoid ligament, lesser cornu of the hyoid bone (chondropharyngeal part) and greater cornu of the hyoid bone (ceratopharyngeal part); insertion, pharyngeal raphe in the posterior wall of the pharynx; action, narrows pharynx in the act of swallowing; nerve supply, pharyngeal plexus.musculus constrictor pharyngis medius [NA];
middle scalene m. scalenus medius m
mimetic m.'s m.'s of facial expression
mucocutaneous m. cutaneomucous m
Müller's m. 1. orbitalis m 2. circular fibers, under fiber 3. superior tarsal m
multifidus m. origin, from the sacrum, sacroiliac ligament, mamillary processes of the lumbar vertebrae, transverse processes of thoracic vertebrae, and articular processes of last four cervical vertebrae; insertion, into the spinous processes of all the vertebrae up to and including the axis; action, rotates vertebral column; nerve supply, dorsal primary rami of spinal nerves.musculus multifidus [NA], intermediate layer of the transversospinalis m.'s, musculus multifidus spinae;
multipennate m. a m. with several central tendons toward which the m. fibers converge like the barbs of feathers.musculus multipennatus [NA];
mylohyoid m. origin, mylohyoid line of mandible; insertion, upper border of hyoid bone and raphe separating m. from its fellow; action, elevates floor of mouth and the tongue, depresses jaw when hyoid is fixed; nerve supply, nerve to mylohyoid from mandibular division of trigeminal.musculus mylohyoideus [NA], mylohyoideus;
nasal m. nasalis m
nasalis m. compound m. consisting of: a transverse part (pars transversa musculi nasalis [NA], musculus compressor naris) arising from the maxilla above the root of the canine tooth on each side and forming an aponeurosis across the bridge of the nose; and an alar part (pars alaris musculi nasalis [NA], musculus dilator naris) arising from the maxilla above the lateral incisor and attaching to the wing of the nose; the alar part dilates the nostril; nerve supply, facial.musculus nasalis [NA], nasal m;
m.'s of neck the anterolateral m.'s of the neck including the platysma, sternocleidomastoid, suprahyoid m.'s, infrahyoid m.'s, longus colli and scalene m.'s.musculi colli [NA];
m. of notch of helix an occasional m. on the cranial surface of the auricle spanning the antitragohelicine fissure.musculus incisurae helicis [NA], musculus intertragicus;
oblique arytenoid m. origin, muscular process of arytenoid cartilage; insertion, summit of arytenoid cartilage of opposite side and continuing as the aryepiglottic muscle in the aryepiglottic fold to the epiglottis; action, narrows the interarytenoid portion of the rima glottidis; nerve supply, recurrent laryngeal.musculus arytenoideus obliquus [NA], arytenoideus;
oblique m. of auricle oblique auricular m
oblique auricular m. a thin band of oblique muscular fibers extending from the upper part of the eminence of the concha to the convexity of the helix, running across the groove corresponding to the inferior crus of the anthelix.musculus obliquus auriculae [NA], oblique m. of auricle, Tod's m;
obliquus capitis inferior m. origin, spinous process of axis; insertion, transverse process of the atlas; action, rotates head; origin, spinous process of axis; insertion, transverse process of the atlas; nerve supply, suboccipital. See also suboccipital m.'s.musculus obliquus capitis inferior [NA], inferior oblique m. of head;
obliquus capitis superior m. origin, transverse process of atlas; insertion, lateral third of inferior nuchal line; action, rotates head; nerve supply, suboccipital. See also suboccipital m.'s.musculus obliquus capitis superior [NA], superior oblique m. of head;
obturator externus m. origin, lower half of margin of obturator foramen and adjacent part of external surface of obturator membrane; insertion, trochanteric fossa of greater trochanter; action, rotates thigh laterally; nerve supply, obturator.musculus obturator externus [NA], external obturator m;
obturator internus m. origin, pelvic surface of obturator membrane and margin of obturator foramen; insertion, passes out of pelvis through lesser sciatic foramen, in so doing, making a 90° turn to insert into the medial surface of greater trochanter; action, rotates thigh laterally; nerve supply, nerve to obturator internus (sacral plexus).musculus obturator internus [NA], internal obturator m;
occipitalis m. occipital belly of occipitofrontalis muscle
occipitofrontal m. occipitofrontalis m
occipitofrontalis m. it is a part of m. epicranius; the occipital belly (occipitalis m.) arises from the occipital bone and inserts into the galea aponeurotica; the frontal belly (frontalis m.) arises from the galea and inserts into the skin of the eyebrow and nose; action, to move the scalp; nerve supply, facial.musculus occipitofrontalis [NA], occipitofrontal m;
ocular m.'s extraocular m.'s
Oehl's m.'s strands of m. fibers in the chordae tendineae of the left atrioventricular valve.
omohyoid m. formed of two bellies attached to intermediate tendon; origin, by inferior belly from upper border of scapula between superior angle and notch; insertion, by superior belly into hyoid bone; action, depresses hyoid; nerve supply, upper cervical spinal nerves through ansa cervicalis.musculus omohyoideus [NA], omohyoid;
opponens digiti minimi m. origin, hamulus of the hamate bone and transverse carpal ligament; insertion, shaft of fifth metacarpal; action, "cups" palm, drawing ulnar side of hand toward center of palm; nerve supply, ulnar.musculus opponens digiti minimi [NA], musculus opponens digiti quinti, musculus opponens minimi digiti, opposer m. of little finger;
opponens pollicis m. origin, ridge of trapezium and flexor retinaculum; insertion, anterior surface of the full length of the shaft of the first metacarpal bone; action, acts at carpometacarpal joint to "cup" palm, enabling one to oppose thumb to other fingers; nerve supply, median.musculus opponens pollicis [NA], opposer m. of thumb;
opposer m. of little finger opponens digiti minimi m
opposer m. of thumb opponens pollicis m
orbicular m. orbicularis m
orbicular m. of eye orbicularis oculi m
orbicularis m. a sphincter-like sheet of m. that encircles an orifice such as the mouth or the palpebral fissures.musculus orbicularis [NA], orbicular m., orbicularis (2);
orbicularis oculi m. consists of three portions: orbital part, or external portion, which arises from frontal process of maxilla and nasal process of frontal bone, encircles aperture of orbit, and is inserted near origin; palpebral part, or internal portion, which arises from medial palpebral ligament, passes through each eyelid, and is inserted into lateral palpebral raphe; lacrimal part (tensor tarsi muscle, Duverney's or Horner's muscle) arises from posterior lacrimal crest and passes across lacrimal sac to join palpebral portion; action, closes eye, wrinkles forehead vertically; nerve supply, facial.musculus orbicularis oculi [NA], musculus orbicularis palpebrarum, orbicular m. of eye, sphincter oculi;
orbicularis oris m. origin, by nasolabial band from septum of the nose, by superior incisive bundle from incisor fossa of maxilla, by inferior incisive bundle from lower jaw each side of symphysis; insertion, fibers surround mouth between skin and mucous membrane of lips and cheeks, and are blended with other m.'s; action, closes lips; nerve supply, facial.musculus orbicularis oris [NA], musculus sphincter oris, orbicular m. of mouth, sphincter oris;
orbicular m. of mouth orbicularis oris m
orbital m. orbitalis m
orbitalis m. a rudimentary nonstriated m., crossing the infraorbital groove and sphenomaxillary fissure, intimately united with the periosteum of the orbit.musculus orbitalis [NA], Müller's m. (1), orbital m;
palatoglossus m. forms anterior pillar of tonsillar fossa; origin, oral surface of soft palate; insertion, side of tongue; action, raises back of tongue and narrows fauces; nerve supply, pharyngeal plexus (cranial root of accessory nerve).musculus palatoglossus [NA], glossopalatinus, musculus glossopalatinus, palatoglossus;
palatopharyngeal m. palatopharyngeus m
palatopharyngeus m. origin, soft palate; forms the posterior pillar of the fauces or tonsillar fossa; insertion, posterior border of thyroid cartilage and aponeurosis of pharynx; action, narrows fauces, depresses soft palate, elevates pharynx and larynx; nerve supply, pharyngeal plexus (cranial root of accessory nerve).musculus palatopharyngeus [NA], musculus pharyngopalatinus, palatopharyngeal m., palatopharyngeus, pharyngopalatinus, pharyngostaphylinus;
palatouvularis m. uvulae m
palmar interosseous m. three m.'s in the hand; origin, first: ulnar side of second metacarpal; second and third: radial sides of fourth and fifth metacarpals; insertion, first: into ulnar side of index; second and third: into radial sides of ring and little fingers; action, adducts fingers toward axis of middle finger; nerve supply, ulnar. See also flexor pollicis brevis m.musculus interosseus palmaris [NA], musculus interosseus volaris;
palmaris brevis m. origin, ulnar side of central portion of the palmar aponeurosis; insertion, skin of ulnar side of hand; action, wrinkles skin on medial side of palm; nerve supply, ulnar.musculus palmaris brevis [NA], short palmar m;
palmaris longus m. origin, medial epicondyle of humerus; insertion, flexor retinaculum of wrist and palmar fascia; action, makes palmar fascia tense and flexes the hand and forearm; is absent about 20% of the time; when tensed, its tendon stands out sharply at the wrist and overlies the median nerve; nerve supply, median.musculus palmaris longus [NA], long palmar m;
panniculus carnosus m. 1. a sheet of m., lying beneath the skin, by which the skin can be made to shiver; it is especially well developed in the horse; 2. in man, platysma.
papillary m. one of the group of myocardial bundles which terminate in the chordae tendineae which attach to the cusps of the atrioventricular valves; each has an anterior and a posterior papillary muscle; the right ventricle sometimes has a septal papillary muscle.musculus papillaris [NA];
pectinate m.'s prominent ridges of atrial myocardium located on the inner surface of much of the right atrium and both auricles.musculi pectinati [NA], pectinate fibers;
pectineal m. pectineus m
pectineus m. origin, crest of pubis; insertion, pectineal line of femur; action, adducts thigh and assists in flexion; nerve supply, obturator and femoral.musculus pectineus [NA], pectineal m;
pectoralis major m. origin, clavicular part (pars clavicularis), medial half of clavicle; sternocostal part (pars sternocostalis), anterior surface of manubrium and body of sternum and cartilages of first to sixth ribs; abdominal part (pars abdominalis), aponeurosis of external oblique; insertion, crest of greater tubercle of humerus; action, adducts and medially rotates arm; nerve supply, anterior thoracic.musculus pectoralis major [NA], greater pectoral m;
pectoralis minor m. origin, third to fifth ribs at the costochondral articulations; insertion, tip of coracoid process of scapula; action, draws down scapula or raises ribs; nerve supply, medial pectoral nerve.musculus pectoralis minor [NA], smaller pectoral m;
pectorodorsal m. pectorodorsalis m
pectorodorsalis m. an anomalous m. or tendinus slip that passes across the axilla from the pectoralis major to insert with the latissimus dorsi onto the humerus. Though to be a vestige of the panniculus carnosus muscle of lower mammals.axillary arch m., axillary arch, pectorodorsal m;
pennate m. See bipennate m., unipennate m.
perineal m.'s the muscles located in the perineal region; these are the external anal sphincter, the superficial transverse perineal m., ischiocavernosus m., bulbospongiosus m., deep transverse perineal m., and sphincter urethrae m.musculi perinei [NA];
peroneus brevis m. origin, lower two-thirds of lateral surface of fibula; insertion, base of fifth metatarsal bone; action, everts foot; nerve supply, superficial peroneal.musculus fibularis brevis [NA], musculus peroneus brevis [NA], short fibular m., short peroneal m;
peroneus longus m. origin, upper two-thirds of outer surface of fibula and lateral condyle of tibia; insertion, by tendon passing behind lateral malleolus and across sole of foot to medial cuneiform and base of first metatarsal; action, plantar flexes and everts foot; nerve supply, superficial peroneal.musculus fibularis longus [NA], musculus peroneus longus [NA], long fibular m., long peroneal m;
peroneus tertius m. origin, in common with m. extensor digitorum longus; insertion, dorsum of base of fifth metatarsal bone; nerve supply, deep branch of peroneal; action, assists in dorsiflexion and eversion of foot.musculus fibularis tertius [NA], musculus peroneus tertius [NA], third peroneal m;
piriform m. piriformis m
piriformis m. origin, margins of pelvic sacral foramina and greater sciatic notch of ilium; insertion, upper border of greater trochanter; action, rotates thigh laterally; nerve supply, nerve to piriformis (sciatic plexus).musculus piriformis [NA], musculus pyriformis, piriform m;
plantar m. plantaris m
plantar interosseous m. three intrinsic m.'s of foot; origin, the medial side of the third, fourth, and fifth metatarsal bones; insertion, corresponding side of proximal phalanx of the same toes; action, adducts three lateral toes; nerve supply, lateral plantar.musculus interosseus plantaris [NA];
plantaris m. origin, lateral supracondylar ridge; insertion, medial margin of tendo achillis and deep fascia of ankle; action, traditionally described as plantar flexion of foot; many investigators now believe the plantaris muscle to be primarily a proprioceptive organ; nerve supply, tibial nerve.musculus plantaris [NA], musculus tibialis gracilis, plantar m;
plantar quadrate m. quadratus plantae m
platysma m. origin, subcutaneous layer and fascia covering pectoralis major and deltoid at level of first or second rib; insertion, lower border of mandible, risorius and platysma of opposite side; action, depresses lower lip, forms ridges in skin of neck and upper chest when jaws are "clenched", denoting stress, anger; nerve supply, cervical branch of facial.platysma [NA], musculus platysma myoides, musculus platysma, musculus subcutaneus colli, musculus tetragonus;
pleuroesophageal m. muscular fasciculi, arising from the mediastinal pleura, which reinforce musculature of esophagus.musculus pleuroesophageus [NA];
popliteal m. popliteus m
popliteus m. origin, lateral condyle of femur; insertion, posterior surface of tibia above oblique line; action, from the fully extended and "locked" position, rotates the femur medially, on the fixed (planted) tibial plateau about 5°, "unlocking" the knee to enable flexion to occur; nerve supply, tibial.musculus popliteus [NA], popliteal m., popliteus (3);
posterior auricular m. origin, mastoid process; insertion, posterior portion of root of auricle; action, draws back the pinna; nerve supply, facial.musculus auricularis posterior [NA], musculus retrahens aurem, musculus retrahens auriculam;
posterior cervical intertransversarii m.'s origin, lateral part: posterior tubercle of cervical transverse process; medial part: transverse process; insertion, corresponding parts of next superior transverse process; action, abducts cervical vertebrae; nerve supply, lateral part: ventral primary rami of cervical spinal nerves; medial part: dorsal primary rami of cervical spinal nerves.musculi intertransversarii posteriores cervicis [NA], posterior cervical intertransverse m.'s;
posterior cervical intertransverse m.'s posterior cervical intertransversarii m.'s
posterior cricoarytenoid m. origin, depression on posterior surface of lamina of cricoid; insertion, muscular process of arytenoid; action, abducts vocal folds, widening rima glottidis as for taking a breath; nerve supply, recurrent laryngeal.musculus cricoarytenoideus posterior [NA];
posterior scalene m. scalenus posterior m
posterior tibial m. tibialis posterior m
Pozzi's m. extensor digitorum brevis m. of hand
procerus m. insertion, into frontalis; action, assists frontalis; origin, from membrane covering bridge of nose; nerve supply, branch of facial.musculus procerus [NA], musculus pyramidalis nasi, procerus;
pronator quadratus m. origin, distal fourth of anterior surface of ulna; insertion, distal fourth of anterior surface of radius; action, pronates forearm; nerve supply, anterior interosseous.musculus pronator quadratus [NA], quadrate pronator m;
pronator teres m. origin, superficial (humeral) head (ulnar) from the common flexor origin on the medial epicondyle of the humerus, deep (ulnar) head from the medial side of the coronoid process of the ulna; insertion, middle of the lateral surface of the radius; action, pronates forearm; nerve supply, median.musculus pronator teres [NA], musculus pronator radii teres, round pronator m;
psoas major m. origin, bodies of vertebrae and intervertebral disks from the twelfth thoracic to the fifth lumbar, and transverse processes of the lumbar vertebrae; insertion, forms a common insertion with iliacus m.'s into lesser trochanter of femur; action, flexes hip joint; nerve supply, lumbar plexus (ventral rami of first, second and usually third lumbar spinal nerves).musculus psoas major [NA], greater psoas m;
psoas minor m. an inconstant m., absent in about 40%; origin, bodies of twelfth thoracic and first lumbar vertebrae and disk between them; insertion, iliopubic eminence via iliopectineal arch (iliac fascia); action, assists in flexion of lumbar spine; nerve supply, lumbar plexus.musculus psoas minor [NA], smaller psoas m;
pubococcygeal m. pubococcygeus m
pubococcygeus m. fibers of the levator ani, arising from the pelvic surface of the body of the pubis and adjacent tendinous arch of obturator fascia, attaching to the coccyx.musculus pubococcygeus [NA], pubococcygeal m;
puboprostatic m. smooth m. fibers within the puboprostatic ligament.musculus puboprostaticus [NA];
puborectal m. puborectalis m
puborectalis m. the medial part of the m. levator ani (pubococcygeus muscle) that passes from the body of the pubis around the anus to form a muscular sling at the level of the anorectal junction; it contracts to increase the perineal flexure during a peristalsis to maintain fecal continence and relaxes to allow defecation.musculus puborectalis [NA], Braune's m., puborectal m;
pubovaginal m. pubovaginalis m
pubovaginalis m. in the female, the most medial fibers of the levator ani (pubococcygeus) m. that extend from the pubis into the lateral walls of the vagina.musculus pubovaginalis [NA], pubovaginal m;
pubovesical m. pubovesicalis m
pubovesicalis m. smooth m. fibers within the pubovesical ligament in the female.musculus pubovesicalis [NA], pubovesical m;
pyramidal m. pyramidalis m
pyramidal m. of auricle pyramidal auricular m
pyramidal auricular m. an occasional prolongation of the fibers of the tragicus to the spina helicis.musculus pyramidalis auriculae [NA], Jung's m., pyramidal m. of auricle;
pyramidalis m. origin, crest of pubis; insertion, lower portion of linea alba; action, makes linea alba tense; nerve supply, subcostal.musculus pyramidalis [NA], pyramidal m;
quadrate m. quadratus m
quadrate m. of loins quadratus lumborum m
quadrate pronator m. pronator quadratus m
quadrate m. of sole quadratus plantae m
quadrate m. of thigh quadratus femoris m
quadrate m. of upper lip musculus quadratus labii superioris
quadratus m. a m. that is more or less square in shape.musculus quadratus [NA], quadrate m;
quadratus fem´oris m. insertion, intertrochanteric ridge; origin, lateral border of tuberosity of ischium; action, rotates thigh laterally; nerve supply, nerve to quadratus femoris (sacral plexus).musculus quadratus femoris [NA], quadrate m. of thigh;
quadratus lumborum m. origin, iliac crest, iliolumbar ligament, and transverse processes of lower lumbar vertebrae; insertion, twelfth rib and transverse processes of upper lumbar vertebrae; action, abducts trunk; nerve supply, ventral primary rami of upper lumbar spinal nerves.musculus quadratus lumborum [NA], lumbar quadrate m., quadrate m. of loins;
quadratus plantae m. origin, by two heads from the lateral and medial borders of the inferior surface of the calcaneus; insertion, tendons of flexor digitorum longus; action, assists long flexor; nerve supply, lateral plantar.musculus flexor accessorius [NA], musculus quadratus plantae [NA], accessory flexor m. of foot, caro quadrata sylvii, musculus pronator pedis, plantar quadrate m., quadrate m. of sole;
quadriceps fem´oris m. origin, by four heads: rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis; insertion, patella, and thence by ligamentum patellae to tuberosity of tibia; action, extends leg; flexes thigh by action of rectus femoris; nerve supply, femoral.musculus quadriceps femoris [NA], musculus quadriceps extensor femoris, quadriceps m. of thigh;
quadriceps m. of thigh quadriceps femoris m
radial flexor m. of wrist flexor carpi radialis m
rectococcygeal m. rectococcygeus m
rectococcygeus m. a band of smooth m. fibers passing from the posterior surface of the rectum to the anterior surface of second or third coccygeal segment.musculus rectococcygeus [NA], rectococcygeal m;
rectourethral m. rectourethralis m
rectourethralis m. smooth m. fibers that pass forward from the longitudinal m. layer of the rectum to the membranous urethra in the male.musculus rectourethralis [NA], rectourethral m;
rectouterine m. a band of fibrous tissue and smooth muscle fibers passing between the cervix of the uterus and the rectum in the rectouterine fold, on either side.musculus rectouterinus [NA];
rectovesical m. rectovesicalis m
rectovesicalis m. smooth m. fibers in the sacrogenital fold in the male; they correspond to rectouterinus m.musculus rectovesicalis [NA], rectovesical m;
rectus m. of abdomen rectus abdominis m
rectus abdominis m. m. of ventral abdominal wall, flanking the linea alba, and characterized by tendinous intersections separating its length into multiple bellies; origin, crest and symphysis of the pubis; insertion, xiphoid process and fifth to seventh costal cartilages; action, flexes lumbar vertebral column, draws thorax downward toward pubis; nerve supply, thoracoabdominal nerves.musculus rectus abdominis [NA], rectus m. of abdomen;
rectus capitis anterior m. 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.musculus rectus capitis anterior [NA], anterior rectus m. of head, musculus rectus capitis anticus minor;
rectus capitis lateralis m. origin, transverse process of atlas; insertion, jugular process of occipital bone; action, inclines head to one side; nerve supply, ventral primary ramus of first cervical spinal nerve.musculus rectus capitis lateralis [NA], lateral rectus m. of the head;
rectus capitis posterior major m. origin, spinous process of axis; insertion, middle of inferior nuchal line of occipital bone; action, rotates and draws head backward; nerve supply, dorsal branch of first cervical (suboccipital). See also suboccipital m.'s.musculus rectus capitis posterior major [NA], greater posterior rectus m. of head, musculus rectus capitis posticus major;
rectus capitis posterior minor m. origin, from posterior tubercle of atlas; insertion, medial third of inferior nuchal line of occipital bone; action, rotates head and draws it backward; nerve supply, dorsal branch of first cervical (suboccipital). See also suboccipital m.'s.musculus rectus capitis posterior minor [NA], musculus rectus capitis posticus minor, smaller posterior rectus m. of head;
rectus femoris m. origin, anterior inferior spine of ilium and upper margin of acetabulum; insertion, via common tendon of quadriceps femoris into patella, and via patellar ligament to tibial tuberosity.musculus rectus femoris [NA], rectus m. of thigh;
rectus m. of thigh rectus femoris m
red m. slow-twitch m. in which small dark "red" m. fibers predominate; myoglobin is abundant and great numbers of mitochondria occur, characterized by slow, sustained (tonic) contraction. Contrast with white m.
Reisseisen's m.'s microscopic smooth m. fibers in the smallest bronchial tubes.
rhomboideus major m. origin, spinous processes and corresponding supraspinous ligaments of first four thoracic vertebrae; insertion, medial border of scapula below spine; action, draws scapula toward vertebral column; nerve supply, dorsal of scapula nerve.musculus rhomboideus major [NA], greater rhomboid m;
rhomboid minor m. origin, spinous processes of sixth and seventh cervical vertebrae; insertion, medial margin of scapula above spine; action, draws scapula toward vertebral column and slightly upward; nerve supply, dorsal nerve of scapula.musculus rhomboideus minor [NA], lesser rhomboid m;
rider's m.'s the adductor m.'s of the thigh, which come into play especially in horseback riding.
Riolan's m. 1. marginal fibers of the palpebral part of the orbicularis oculi m.; 2. cremaster m
risorius m. origin, from platysma and fascia of masseter; insertion, orbicularis oris and skin at corner of mouth; action, draws angle of mouth laterally, lenghthening rima oris; nerve supply, facial.musculus risorius [NA], Albinus' m. (1), Santorini's m;
rotator m.'s rotatores m.'s
rotatores m.'s deepest of the three layers of transversospinalis m.'s, chiefly developed in the thoracic region; they arise from the transverse process of one vertebra and are inserted into the root of the spinous process of the next two or three vertebrae above; action, traditionally described as a column, it is more likely that these m.'s, provided with a very high density of m. spindles, are organs of proprioception; nerve supply, dorsal primary rami of the spinal nerves.musculi rotatores [NA], rotator m.'s;
rotatores cervicis m.'s the rotator m.'s attached to the cervical vertebrae.musculi rotatores cervicis [NA], cervical rotator m.'s;
rotatores lumborum m.'s the rotator m.'s of the lumbar vertebrae.musculi rotatores lumborum [NA], lumbar rotator m.'s;
rotatores thoracis m.'s the rotators of the thoracic vertebrae.musculi rotatores thoracis [NA], thoracic rotator m.'s;
Rouget's m. circular fibers, under fiber
round pronator m. pronator teres m
Ruysch's m. the muscular tissue of the fundus of the uterus.
salpingopharyngeal m. salpingopharyngeus m
salpingopharyngeus m. origin, medial lamina of cartilaginous part of auditory tube; insertion, longitudinal muscular layer of pharynx in association with m. palatopharyngeus; action, assists in elevating pharynx and, according to some, assists in opening the auditory tube during swallowing; nerve supply, pharyngeal plexus.musculus salpingopharyngeus [NA], salpingopharyngeal m;
Santorini's m. risorius m
sartorius m. origin, anterior superior spine of ilium; insertion, medial border of tuberosity of tibia; action, flexes thigh and leg, rotates leg medially and thigh laterally; nerve supply, femoral.musculus sartorius [NA], tailor's m;
scalenus anterior m. 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.musculus scalenus anterior [NA], anterior scalene m., musculus scalenus anticus;
scalenus medius m. origin, costotransverse lamellae of transverse processes of second to sixth cervical vertebrae; insertion, first rib posterior to subclavian artery; action, raises first rib; nerve supply, cervical plexus.musculus scalenus medius [NA], middle scalene m;
scalenus minimus m. an occasional independent muscular fasciculus between the scalenus anterior and medius, and having the same action and innervation.musculus scalenus minimus [NA], Albinus' m. (2), Sibson's m., smallest scalene m;
scalenus posterior m. origin, posterior tubercles of transverse processes of fourth to sixth cervical vertebrae; insertion, lateral surface of second rib; action, elevates second rib; nerve supply, cervical and brachial plexuses.musculus scalenus posterior [NA], musculus scalenus posticus, posterior scalene m;
scalp m. epicranius m
Sebileau's m. deep fibers of the dartos tunic which pass into the scrotal septum.
second tibial m. musculus tibialis secundus
semimembranosus m. origin, tuberosity of ischium; insertion, medial condyle of tibia and by membrane to tibial collateral ligament of knee joint, popliteal fascia, and via its reflected tendon of insertion (oblique popiteal ligament) lateral condyle of femur; action, flexes knee and rotates leg medially when knee is flexed; and contributes to the stability of extended knee by making capsule of knee joint tense; nerve supply, tibial.musculus semimembranosus [NA];
semispinal m. semispinalis m
semispinal m. of head semispinalis capitis m
semispinalis m. the most superficial layer of the three layers of the transversospinal m.; comprised of semispinalis capitis, semispinalis cervicis, and semispinalis thoracis m.'s.musculus semispinalis [NA], semispinal m;
semispinalis capitis m. origin, transverse processes of five or six upper thoracic and articular processes of four lower cervical vertebrae; insertion, occipital bone between superior and inferior nuchal lines; action, rotates head and draws it backward; nerve supply, dorsal primary rami of cervical spinal nerves.musculus semispinalis capitis [NA], musculus complexus, semispinal m. of head;
semispinalis cervicis m. continuous with m. semispinalis thoracis; origin, transverse processes of second to fifth thoracic vertebrae; insertion, spinous processes of axis and third to fifth cervical vertebrae; action, extends cervical spine; nerve supply, dorsal primary rami of cervical and thoracic spinal nerves.musculus semispinalis cervicis [NA], musculus semispinalis colli, semispinal m. of neck;
semispinalis thoracis m. origin, transverse processes of fifth to eleventh thoracic vertebrae; insertion, spinous processes of first four thoracic and fifth and seventh cervical vertebrae; action, extends vertebral column; nerve supply, dorsal primary rami of cervical and thoracic spinal nerves.musculus semispinalis thoracis [NA], musculus semispinalis dorsi, semispinal m. of thorax;
semispinal m. of neck semispinalis cervicis m
semispinal m. of thorax semispinalis thoracis m
semitendinosus m. origin, ischial tuberosity; insertion, medial surface of the upper fourth of shaft of tibia; action, extends thigh, flexes leg and rotates it medially; nerve supply, tibial.musculus semitendinosus [NA];
serratus anterior m. origin, from center 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.musculus serratus anterior [NA], anterior serratus m., costoscapularis, musculus serratus magnus;
serratus posterior inferior m. origin, with latissimus dorsi, from spinous processes of two lower thoracic and two upper lumbar vertebrae; insertion, into lower borders of last four ribs; action, draws lower ribs backward and downward; nerve supply, ninth to twelfth intercostal.musculus serratus posterior inferior [NA], inferior posterior serratus m;
serratus posterior superior m. origin, from spinous processes of two lower cervical and two upper thoracic vertebrae; insertion, into lateral side of angles of second to fifth ribs; nerve supply, first to fourth intercostals.musculus serratus posterior superior [NA], superior posterior serratus m;
shawl m. obsolete term for trapezius m.
short abductor m. of thumb abductor pollicis brevis m
short adductor m. adductor brevis m
short extensor m. of great toe extensor hallucis brevis m
short extensor m. of thumb extensor pollicis brevis m
short extensor m. of toes extensor digitorum brevis m
short fibular m. peroneus brevis m
short flexor m. of great toe flexor hallucis brevis m
short flexor m. of little finger flexor digiti minimi brevis m. of hand
short flexor m. of little toe flexor digiti minimi brevis m. of foot
short flexor m. of thumb flexor pollicis brevis m
short flexor m. of toes flexor digitorum brevis m
short levatores costarum m.'s origin, the transverse processes of last cervical and eleven thoracic vertebrae; insertion ribs immediately below, between angle and tubercle.musculi levatores costarum breves;
short palmar m. palmaris brevis m
short peroneal m. peroneus brevis m
short radial extensor m. of wrist extensor carpi radialis brevis m
Sibson's m. scalenus minimus m
skeletal m. grossly, a collection of striated m. fibers connected at either or both extremities with the bony framework of the body; it may be an appendicular or an axial m.; histologically, a m. consisting of elongated, multinucleated, transversely striated skeletal m. fibers together with connective tissues, blood vessels, and nerves; individual m. fibers are surrounded by fine reticular and collagen fibers (endomysium); bundles (fascicles) of m. fibers are surrounded by irregular connective tissue (perimysium); the entire m. is surrounded, except at the m. tendon junction, by a dense connective tissue (epimysium).musculus skeleti;
smaller m. of helix helicis minor m
smaller pectoral m. pectoralis minor m
smaller posterior rectus m. of head rectus capitis posterior minor m
smaller psoas m. psoas minor m
smallest scalene m. scalenus minimus m
smooth m. one of the m. fibers of the internal organs, blood vessels, hair follicles, etc.; contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei and a length from 20 to 200 mum, or even longer in the pregnant uterus; although transverse striations are lacking, both thick and thin myofibrils occur; smooth m. fibers are bound together into sheets or bundles by reticular fibers, and frequently elastic fiber nets are also abundant. See also involuntary m.'s.unstriated m., unstriped m., visceral m;
Soemmerring's m. levator m. of thyroid gland
soleus m. origin, posterior surface of head and upper third of shaft of fibula, oblique line and middle third of medial margin of tibia, and a tendinous arch passing between tibia and fibula over the popliteal vessels; insertion, with gastrocnemius by tendo calcaneus (achillis) into tuberosity of calcaneus; action, plantar flexion of foot; nerve supply, tibial.musculus soleus [NA];
sphincter m. sphincter
sphincter m. of common bile duct sphincter of common bile duct
sphincter m. of pancreatic duct sphincter of pancreatic duct
sphincter m. of pupil sphincter pupillae
sphincter m. of pylorus pyloric sphincter
sphincter m. of urethra sphincter urethrae
sphincter m. of urinary bladder sphincter vesicae
spinal m. spinalis m
spinal m. of head spinalis capitis m
spinalis m. the medial component of the erector spinae muscle; it is comprised of the spinalis capitis, spinalis cervicis, and spinalis thoracis muscles.musculus spinalis [NA], spinal m;
spinalis capitis m. an inconstant extension of spinalis cervicis to the occipital bone, sometimes fusing with semispinalis capitis.musculus spinalis capitis [NA], biventer cervicis, spinal m. of head;
spinalis cervicis m. an inconstant or rudimentary muscle; origin, spinous processes of sixth and seventh cervical vertebrae; insertion, spinous processes of axis and third cervical vertebra; action, extends cervical spine; nerve supply, dorsal primary rami of cervical.musculus spinalis cervicis [NA], musculus spinalis colli, spinal m. of neck;
spinalis thoracis m. origin, spinous processes of upper lumbar and two lower thoracic vertebrae; insertion, spinous processes of middle and upper thoracic vertebrae; action, supports and extends vertebral column; nerve supply, dorsal primary rami of thoracic and upper lumbar.musculus spinalis thoracis [NA], musculus spinalis dorsi, spinal m. of thorax;
spinal m. of neck spinalis cervicis m
spinal m. of thorax spinalis thoracis m
spindle-shaped m. fusiform m
splenius capitis m. origin, from ligamentum nuchae of last four cervical vertebrae and supraspinous ligament of first and second thoracic vertebrae; insertion, lateral half of superior nuchal line and mastoid process; action, rotates head and extends neck; nerve supply, dorsal primary rami of second to sixth cervical spinal nerves.musculus splenius capitis [NA], splenius m. of head;
splenius cervicis m. origin, from supraspinous ligament and spinous processes of third to fifth thoracic vertebrae; insertion, posterior tubercles of transverse processes of first and second (sometimes third) cervical vertebrae; action, rotates and extends neck; nerve supply, dorsal primary rami of fourth to eighth cervical spinal nerves.musculus splenius cervicis [NA], musculus splenius colli, splenius m. of neck;
splenius m. of head splenius capitis m
splenius m. of neck splenius cervicis m
stapedius m. origin, internal walls of pyramidal eminence in tympanic cavity; insertion, neck of the stapes; action, dampens vibration of stapes by drawing head of stapes backward as a result of a protective reflex stimulated by loud noise; nerve supply, facial.musculus stapedius [NA], stapedius;
sternal m. sternalis m
sternalis m. an inconstant muscle, running parallel to the sternum across the costosternal origin of the pectoralis major, and usually connected with the sternocleidomastoid and rectus abdominis muscles due to their common development source.musculus sternalis [NA], musculus rectus thoracis, sternal m;
sternochondroscapular m. an occasional muscle arising from the manubrium of the sternum and first costal cartilage and passing lateralward and backward to be inserted into the upper border of the scapula.musculus sternochondroscapularis;
sternoclavicular m. an occasional m. a slip from the subclavius muscle, passing from the upper part of the sternum to the clavicle beneath the pectoralis major m.musculus sternoclavicularis;
sternocleidomastoid m. origin, by two heads from anterior surface of manubrium of the sternum and sternal end of clavicle; insertion, mastoid process and lateral half of superior nuchal line; action, turns head obliquely to opposite side; when acting together, flex the neck and extend the head; nerve supply, motor by accessory, sensory by cervical plexus.musculus sternocleidomastoideus [NA], sternomastoid m;
sternocostalis m. transversus thoracis m
sternohyoid m. origin, posterior surface of manubrium sterni and first costal cartilage; insertion, body of hyoid bone; action, depresses hyoid bone; nerve supply, upper cervical via spinal nerves(ansa cervicalis).musculus sternohyoideus [NA];
sternomastoid m. sternocleidomastoid m
sternothyroid m. origin, posterior surface of manubrium of sternum and first or second costal cartilage; insertion, oblique line of thyroid cartilage; action, depresses larynx; nerve supply, upper cervical via spinal nerves (ansa cervicalis).musculus sternothyroideus [NA];
strap m.'s infrahyoid m.'s
striated m. skeletal or voluntary m. in which cross striations occur in the fibers as a result of regular overlapping of thick and thin myofilaments; contrast with smooth muscle. Although cardiac muscle (which is not voluntary muscle) is also striated in appearance, the term "striated muscle" is commonly used as a synonym for voluntary, skeletal muscle.
styloauricular m. an occasional small m. extending from the root of the styloid process to the cartilage of the meatus of the ear.musculus styloauricularis;
styloglossus m. action, retracts tongue; origin, lower end of styloid process; insertion, side and undersurface of tongue; nerve supply, hypoglossal.musculus styloglossus [NA];
stylohyoid m. origin, styloid process of temporal bone; insertion, hyoid bone by two slips on either side of intermediate tendon of digastric; action, elevates hyoid bone; nerve supply, facial.musculus stylohyoideus [NA];
stylopharyngeal m. stylopharyngeus m
stylopharyngeus m. origin, root of styloid process; insertion, thyroid cartilage and wall of pharynx (becomes part of the longitudinal coat): action, elevates pharynx and larynx; nerve supply, glossopharyngeal.musculus stylopharyngeus [NA], stylopharyngeal m;
subanconeus m. articularis cubiti m
subclavian m. subclavius m
subclavius m. origin, first costal cartilage; insertion, inferior surface of acromial end of clavicle; action, fixes clavicle or elevates first rib; nerve supply, subclavian from brachial plexus.musculus subclavius [NA], subclavian m;
subcostal m. one of a number of inconstant muscles of the posterolateral thoracic wall having the same direction as the internal intercostal muscles but extending across (deep to) one or more ribs.musculus subcostalis [NA], musculus infracostalis;
subcrural m. articularis genu m
suboccipital m.'s a group of muscles located immediately below the occipital bone; they are: rectus capitis anterior muscle, rectus capitis posterior major and minor muscles, rectus capitis lateralis m., obliquus capitis superior and inferior muscles; innervated by suboccipital nerve; although actions are described, it is held by many authorities that these muscles act primarily as organs of proprioception.musculi suboccipitales [NA];
subquadricipital m. articularis genu m
subscapular m. subscapularis m
subscapularis m. origin, subscapular fossa; insertion, lesser tuberosity of humerus; action, rotates arm medially; nerve supply, upper and lower subscapular from posterior cord of brachial plexus (fifth and sixth cervical spinal nerves).musculus subscapularis [NA], subscapular m;
superficial back m.'s m.'s originating from the vertebral column and having their fleshy bellies located in the back, but inserting onto the appendicular skeleton of the upper limb or the ribs. They are not innervated by dorsal primary rami of spinal nerves, as are the deep or true m.'s of the back; includes the trapezius m. (innervated by spinal accessory nerve) and latissimus dorsi, rhomboids, levator scapulae, and thoracic m.'s (innervated by ventral primary rami of spinal nerves, or derivatives thereof).
superficial flexor m. of fingers flexor digitorum superficialis m
superficial lingual m. superior longitudinal m. of tongue
superficial transverse perineal m. an inconstant muscle; origin, ramus of ischium; insertion, central tendon of perineum; action, draws back and fixes the central tendon of the perineum; nerve supply, pudendal (perineal).musculus transversus perinei superficialis [NA], superficial transverse m. of perineum, Theile's m;
superficial transverse m. of perineum superficial transverse perineal m
superior auricular m. origin, galea aponeurotica; insertion, cartilage of auricle; action draws pinna of ear upward and backward; nerve supply, facial. Considered by some to be the posterior part of the temporoparietal muscle.musculus auricularis superior [NA], attollens aurem, attollens auriculam, musculus attollens aurem, musculus attollens auriculam;
superior constrictor m. of pharynx origin, medial pterygoid plate (pterygopharyngeal part), pterygomandibular raphe (buccopharyngeal part), mylohyoid line of mandible (mylopharyngeal part), and the mucous membrane of the floor of the mouth and the side of the tongue (glossopharyngeal part); insertion, pharyngeal raphe in the posterior wall of the pharynx; action, narrows pharynx; nerve supply, pharyngeal plexus.musculus constrictor pharyngis superior [NA], musculus cephalopharyngeus;
superior gemellus m. origin, ischial spine and margin of lesser sciatic notch; insertion, tendon of m. obturator internus; action, rotates thigh laterally; nerve supply, sacral plexus.musculus gemellus superior [NA], gemellus;
superior longitudinal m. of tongue an intrinsic muscle of the tongue, running from base to tip on the dorsum just beneath the mucous membrane; action, shortens the upper part of the tongue; nerve supply, motor by hypoglossal, sensory by lingual.musculus longitudinalis superior [NA], superficial lingual m;
superior oblique m. origin, above the medial margin of the optic canal; insertion, by a tendon passing through the trochlea, or pulley, and then reflected backward, downward, and laterally to the sclera between the superior and lateral recti; action, primary, intorsion; secondary, depression and abduction; nerve supply, trochlear nerve.musculus obliquus superior [NA];
superior oblique m. of head obliquus capitis superior m
superior posterior serratus m. serratus posterior superior m
superior rectus m. origin, superior part of common tendinous ring; insertion, superior part of sclera of the eye; action, primary, elevation; secondary, adduction and intorsion; nerve supply, oculomotor.musculus rectus superior [NA], attollens oculi;
superior tarsal m. a well defined layer of smooth muscle that extends from the aponeurosis of the m. levator palpebrae superioris to the superior tarsus; it is innervated by sympathetic nerves and acts to hold the upper lid in an elevated position; its paralysis in Horner's syndrome result in ptosis.musculus tarsalis superior [NA], Müller's m. (3);
supinator m. origin, lateral epicondyle of humerus radial collateral and anular ligaments, and supinator ridge of ulna; insertion, anterior and lateral surface of radius; action, supinates the forearm; nerve supply, radial (posterior interosseous).musculus supinator [NA], musculus supinator radii brevis;
supraclavicular m. an anomalous muscular slip running from the upper edge of the manubrium of the sternum lateralward to about the middle of the upper surface of the clavicle.musculus supraclavicularis;
suprahyoid m.'s the group of muscles attached to the upper part of the hyoid bone including the digastric, stylohyoid, mylohyoid, and geniohyoid muscles.musculi suprahyoidei [NA];
supraspinalis m. one of a number of muscular bands passing between the tips of the spinous processes of the cervical vertebrae.musculus supraspinalis;
supraspinatus m. origin, supraspinous fossa of scapula; insertion, greater tuberosity of humerus; action, initiates abduction of arm; nerve supply, suprascapular from fifth and sixth cervical.musculus supraspinatus [NA], supraspinous m;
supraspinous m. supraspinatus m
suspensory m. of duodenum a broad flat band of smooth muscle and fibrous tissue attached to the right crus of the diaphragm and to the duodenum at its junction with the jejunum.musculus suspensorius duodeni [NA], Treitz's ligament, Treitz's m;
synergistic m.'s m.'s having a similar and mutually helpful function or action.
tailor's m. sartorius m
temporal m. temporalis m
temporalis m. origin, temporal fossa; insertion, coronoid process of mandible and anterior border of ramus; action elevates mandible (closes jaw); its posterior, nearly horizontally-oriented fibers are the primary retractors of the protruded mandible. nerve supply, deep temporal branches of mandibular division of trigeminal.musculus temporalis [NA], temporal m;
temporoparietal m. temporoparietalis m
temporoparietalis m. the part of epicranius m. that arises from the lateral part of the epicranial aponeurosis and inserts in the cartilage of the auricle.musculus temporoparietalis [NA], temporoparietal m;
tensor fasciae latae m. origin, anterior superior spine and adjacent lateral surface of the ilium; insertion, iliotibial band of fascia lata; action, tenses fascia lata; flexes, abducts and medially rotates thigh; nerve supply, superior gluteal.musculus tensor fasciae latae [NA], musculus tensor fasciae femoris, tensor m. of fascia lata;
tensor m. of fascia lata tensor fasciae latae m
tensor m. of soft palate tensor veli palati m
tensor tarsi m. lacrimal part of orbicularis oculi muscle. See orbicularis oculi m.
tensor tympani m. origin, the cartilaginous part of the auditory (eustachian) tube and the walls of its hemi-canal just above the bony portion of the auditory tube; insertion, handle of malleus; action, draws the handle of the malleus medialward tensing the tympanic membrane to protect it from excessive vibration by loud sounds. nerve supply, branches of trigeminal through the otic ganglion.musculus tensor tympani [NA], tensor m. of tympanic membrane, Toynbee's m;
tensor m. of tympanic membrane tensor tympani m
tensor veli palati m. tensor muscle of soft palate, m. tensor palati; m. palatosalpingeus; m. sphenosalpingostaphylinus; dilator tubae; origin, scaphoid fossa of sphenoid, cartilaginous and membranous part of auditory (eustachian) tube and spine of sphenoid; insertion, posterior border of hard palate and aponeurosis of soft palate; action, tenses the soft palate; contributes to opening of auditory tube; nerve supply, branches of trigeminal nerve through the otic ganglion.musculus tensor veli palatini [NA], dilator tubae, musculus palatosalpingeus, musculus sphenosalpingostaphylinus, musculus tensor palati, palatosalpingeus, tensor m. of soft palate;
teres major m. origin, inferior angle and lower third of border of scapula; insertion, medial border of intertubercular groove of humerus; action, adducts and extends arm and rotates it medially; nerve supply, lower subscapular from posterior cord of brachial plexus (fifth and sixth cervical spinal nerves).musculus teres major [NA];
teres minor m. origin, upper two-thirds of the lateral border of scapula; insertion, lower facet of greater tuberosity of humerus; action, adducts arm and rotates it laterally; nerve supply, axillary (fifth and sixth cervical spinal nerves).musculus teres minor [NA];
Theile's m. superficial transverse perineal m
third peroneal m. peroneus tertius m
thoracic interspinal m. thoracic interspinales m.'s
thoracic interspinales m.'s often poorly developed or absent muscles between spinous process of thoracic vertebrae; action, extends thoracic vertebrae; nerve supply, dorsal primary rami of thoracic nerves.musculus interspinalis thoracis [NA], thoracic interspinal m;
thoracic intertransversarii m.'s origin, transverse processes of thoracic vertebrae; insertion, next superior transverse process; action, abducts thoracic vertebrae; nerve supply, dorsal primary rami of thoracic nerves.musculi intertransversarii thoracis [NA], thoracic intertransverse m.'s;
thoracic intertransverse m.'s thoracic intertransversarii m.'s
thoracic longissimus m. longissimus thoracis m
thoracic rotator m.'s rotatores thoracis m.'s
m.'s of thorax the muscles attaching to the rib cage including the pectoral muscles, serratus anterior, subclavius, levator muscles, intercostal muscles, transverse thoracic muscle, subcostal muscles, and diaphragm.musculi thoracis [NA];
thyroarytenoid m. origin, inner surface of thyroid cartilage; insertion, muscular process and outer surface of arytenoid; action, decreases tension on (relaxes) vocal cords lowering the pitch of the voice tone; nerve supply, recurrent laryngeal.musculus thyroarytenoideus [NA], musculus thyroarytenoideus externus;
thyroepiglottic m. , thyroepiglottidean m. origin, inner surface of thyroid cartilage in common with m. thyroarytenoideus; insertion, aryepiglottic fold and margin of epiglottis; action, depresses base of epiglottis; nerve supply, recurrent laryngeal.musculus thyroepiglotticus [NA], depressor m. of epiglottis, ventricularis (2);
thyrohyoid m. apparently a continuation of the sternothyroid; origin, oblique line of thyroid cartilage; insertion, body of hyoid bone; action, approximates hyoid bone to the larynx; nerve supply, upper cervical spinal nerves carried by hypoglossal.musculus thyrohyoideus [NA];
tibialis anterior m. 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.musculus tibialis anterior [NA], anterior tibial m., musculus tibialis anticus;
tibialis posterior m. origin, soleal line and posterior surface of tibia, the head and shaft of the fibula between the medial crest and interosseous border, and the posterior surface of interosseous membrane; insertion, navicular, three cuneiform, cuboid, and second, third, and fourth metatarsal bones; action, plantar flexion and inversion of foot; nerve supply, tibial.musculus tibialis posterior [NA], musculus tibialis posticus, posterior tibial m;
Tod's m. oblique auricular m
m.'s of tongue the extrinsic m.'s include the genioglossus, hyoglossus, chondroglossus, and styloglossus m.'s; the intrinsic muscles are the vertical, transverse, and the superior and inferior longitudinal; all are innervated by the hypoglssal nerve.musculi linguae [NA];
Toynbee's m. tensor tympani m
trachealis m. the band of smooth muscular fibers in the fibrous membrane connecting posteriorly the ends of the tracheal rings.musculus trachealis [NA];
tracheloclavicular m. an anomalous muscle occasionally arising from the cervical vertebrae and inserted into the lateral end of the clavicle.musculus tracheloclavicularis;
tragicus m. a band of vertical muscular fibers on the outer surface of the tragus of the ear.musculus tragicus [NA], m. of tragus, Valsalva's m;
m. of tragus tragicus m
transverse m. of abdomen transversus abdominis m
transverse arytenoid m. a band of muscular fibers passing between the two arytenoid cartilages posteriorly; action, narrows the intercartilaginous portion of the rima glottidis; nerve supply, recurrent laryngeal.musculus arytenoideus transversus [NA], arytenoideus;
transverse m. of auricle transverse auricular m
transverse auricular m. a band of sparse muscular fibers on the cranial surface of the auricle, extending from the eminence of the concha to the eminence of the scapha.musculus transversus auriculae [NA], transverse m. of auricle;
transverse m. of chin transversus menti m
transverse m. of nape transversus nuchae m
transverse m. of thorax transversus thoracis m
transverse m. of tongue an intrinsic muscle of the tongue, the fibers of which arise from the septum and radiate to the dorsum and sides; action, decreases lateral dimension of the tongue; nerve supply, hypoglossal for motor, lingual for sensory.musculus transversus linguae [NA];
transversospinal m. transversospinalis m
transversospinalis m. the group of muscles that originate from transverse processes of vertebrae and pass to spinous processes of higher vertebrae; they act as rotators and include the semispinalis (capitis, cervicis, thoracis), multifidus, and rotatores (cervicis, thoracis, lumborum) muscles. All are innervated by dorsal primary rami of spinal nerves.musculus transversospinalis [NA], transversospinal m;
transversus abdominis m. origin, seventh to twelfth costal cartilages, lumbar fascia, iliac crest, and inguinal ligament; insertion, xiphoid cartilage and linea alba and, through the conjoint tendon, pubic tubercle and pecten; action, compresses abdominal contents; nerve supply, lower thoracic.musculus transversus abdominis [NA], musculus transversalis abdominis, transverse m. of abdomen;
transversus menti m. inconstant fibers of the depressor anguli oris m. continue into the neck and cross to the opposite side inferior to the chin.musculus transversus menti [NA], transverse m. of chin;
transversus nuchae m. an occasional muscle passing between the tendons of the trapezius and sternocleidomastoid, possibly a fasciculus of the posterior auricular muscle.musculus transversus nuchae [NA], transverse m. of nape;
transversus thoracis m. origin, dorsal surface of xiphoid cartilage and lower portion of dorsal surface of body of sternum; insertion, second to sixth costal cartilages; action, contributes to depression of ribs, narrowing chest; nerve supply, intercostal.musculus transversus thoracis [NA], musculus triangularis sterni, sternocostalis m., transverse m. of thorax;
trapezius m. origin, medial third of superior nuchal line, external occipital protuberance, ligamentum nuchae, spinous processes of seventh cervical and the thoracic vertebrae and corresponding supraspinous ligaments; insertion, lateral third of posterior surface of clavicle, anterior side of acromion, and upper and medial border of the spine of the scapula; action, when scapulae are fixed, portions of muscle can act independently: cervical portion elevates scapula, thoracic portion contributes to depression of scapula; upper and lowermost portions act simultaneously to rotate glenoid fossa superiorly; when the entire muscle and especially middle part contracts, the scapulae retract; draws head to one side or backward; nerve supply, motor by accessory, sensory by cervical plexus.musculus trapezius [NA], cowl m., trapezius;
Treitz's m. suspensory m. of duodenum
triangular m. 1. a muscle that is triangular in shape;musculus triangularis (1); 2. depressor anguli oris m
triceps m. of arm triceps brachii m
triceps brachii m. origin, long or scapular head: lateral border of scapula below glenoid fossa, lateral head: lateral and posterior surface of humerus below greater tubercle, medial head: posterior surface of humerus below radial groove; insertion, olecranon of ulna; action, extends elbow; nerve supply, radial.musculus triceps brachii [NA], triceps m. of arm;
triceps m. of calf triceps surae m
triceps coxae m. the obturator internus and superior and inferior gemellus m.'s considered as one muscle, inserting via a single tendon into the greater trochanter of the femur.musculus triceps coxae, triceps m. of hip;
triceps m. of hip triceps coxae m
triceps surae m. the two bellies of the gastrocnemius and soleus considered as one muscle.musculus triceps surae [NA], triceps m. of calf;
true m.'s of back deep m.'s of back
two-bellied m. digastric m
ulnar extensor m. of wrist extensor carpi ulnaris m
ulnar flexor m. of wrist flexor carpi ulnaris m
unipennate m. a muscle with a lateral tendon to which the fibers are attached obliquely, like one half of a feather.musculus unipennatus [NA];
unstriated m. , unstriped m. smooth m
m. of uvula uvulae m
uvulae m. origin, posterior nasal spine; insertion, forms chief bulk of the uvula; action, raises the uvula; nerve supply, pharyngeal plexus.musculus uvulae [NA], m. of uvula, musculus azygos uvulae, palatouvularis m., uvularis;
Valsalva's m. tragicus m
vastus intermedius m. origin, upper three-fourths of anterior surface of shaft of femur; insertion, tibial tuberosity by way of common tendon of quadriceps femoris and patellar ligament; action, extends leg; nerve supply, femoral.musculus vastus intermedius [NA], crureus, femoral m., intermediate great m., intermediate vastus m;
vastus lateralis m. origin, lateral lip of linea aspera as far as great trochanter; insertion, tibial tuberosity by way of common tendon of quadriceps femoris and patellar ligament; action, extends leg; nerve supply, femoral.musculus vastus lateralis [NA], lateral great m., lateral vastus m., musculus vastus externus;
vastus medialis m. origin, medial lip of linea aspera; insertion, tibial tuberosity by way of common tendon of quadriceps femoris and ligamentum patellae; action, extends leg; nerve supply, femoral.musculus vastus medialis [NA], medial great m., medial vastus m., musculus vastus internus;
ventral sacrococcygeal m. ventral sacrococcygeus m
ventral sacrococcygeus m. an inconstant muscle on the pelvic surfaces of the sacrum and coccyx, the remains of a portion of the tail musculature of lower animals.musculus sacrococcygeus ventralis [NA], musculus sacrococcygeus anterior, ventral sacrococcygeal m;
vertical m. of tongue an intrinsic muscle of the tongue, consisting of fibers that pass from the aponeurosis of the dorsum to the aponeurosis of the inferior surface; action, decreases the superior to inferior dimension of (flattens) the tongue; nerve supply, hypoglossal for motor, lingual for sensory.musculus verticalis linguae [NA];
vestigial m. an imperfect structure in man corresponding to a functioning m. in the lower animals.
visceral m. smooth m
vocal m. vocalis m
vocalis m. origin, depression between the two laminae of thyroid cartilage; insertion, portions of vocal process of arytenoid; action, shortens and relaxes vocal cords; nerve supply, recurrent laryngeal; a number of the deeper and finer fibers of the thyroaryteroid m. attached directly to the outer side of the true vocal cord.musculus vocalis [NA], musculus thyroarytenoideus internus, vocal m;
voluntary m. one whose action is under the control of the will; all the striated m.'s, except the heart, are voluntary m.'s.
white m. a rapid or fast-twitch m. in which pale large "white" fibers predominate; mitochondria and myoglobin are relatively sparse compared with red m.; involved in phasic contraction.
Wilson's m. 1. sphincter urethrae 2. certain fibers of the levator ani.
wrinkler m. of eyebrow corrugator supercilii m
zygomaticus major m. origin, zygomatic bone anterior to temporozygomatic suture; insertion, muscles at angle of mouth; action, draws upper lip upward and laterally; nerve supply, facial.musculus zygomaticus major [NA], greater zygomatic m., musculus zygomaticus;
zygomaticus minor m. origin, zygomatic bone posterior to zygomaticomaxillary suture; insertion, orbicularis oris of upper lip; action, draws upper lip upward and outward; nerve supply, facial.musculus zygomaticus minor [NA], caput zygomaticum quadrati labii superioris, lesser zygomatic m;

 

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