For foreign first-year students for autumn term Module Methodical elaboration for practice class on human anatomy for foreign first-year students for autumn term
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The Posterior Tibial Artery (A. Tibialis Posterior) The posterior tibial artery begins at the lower border of the Popliteus, opposite the interval between the tibia and fibula; it extends obliquely downward, and, as it descends, it approaches the tibial side of the leg, lying behind the tibia, and in the lower part of its course is situated midway between the medial malleolus and the medial process of the calcaneal tuberosity. Here it divides beneath the origin of the Adductor hallucis into the medial and lateral plantar arteries. Relations.—The posterior tibial artery lies successively upon the Tibialis posterior, the Flexor digitorum longus, the tibia, and the back of the ankle-joint. It is covered by the deep transverse fascia of the leg, which separates it above from the Gastrocnemius and Soleus; at its termination it is covered by the Abductor hallucis. In the lower third of the leg, where it is more superficial, it is covered only by the integument and fascia, and runs parallel with the medial border of the tendo calcaneus. It is accompanied by two veins, and by the tibial nerve, which lies at first to the medial side of the artery, but soon crosses it posteriorly, and is in the greater part of its course on its lateral side. Behind the medial malleolus, the tendons, bloodvessels, and nerve are arranged, under cover of the laciniate ligament, in the following order from the medial to the lateral side: (1) the tendons of the Tibialis posterior and Flexor digitorum longus, lying in the same groove, behind the malleolus, the former being the more medial. Next is the posterior tibial artery, with a vein on either side of it; and lateral to the vessels is the tibial nerve; about 1.25 cm. nearer the heel is the tendon of the Flexor hallucis longus. Peculiarities in Size.—The posterior tibial is not infrequently smaller than usual, or absent, its place being supplied by a large peroneal artery, which either joins the small posterior tibial artery, or continues alone to the sole of the foot. Branches.—The branches of the posterior tibial artery are: Peroneal. Posterior Medial Malleolar. Nutrient. Communicating. Muscular. Medial Calcaneal. The peroneal artery (a. peronæa) is deeply seated on the back of the fibular side of the leg. It arises from the posterior tibial, about 2.5 cm. below the lower border of the Popliteus, passes obliquely toward the fibula, and then descends along the medial side of that bone, contained in a fibrous canal between the Tibialis posterior and the Flexor hallucis longus, or in the substance of the latter muscle. It then runs behind the tibiofibular syndesmosis and divides into lateral calcaneal branches which ramify on the lateral and posterior surfaces of the calcaneus. It is covered, in the upper part of its course, by the Soleus and deep transverse fascia of the leg; below, by the Flexor hallucis longus.
Muscular. Perforating. Nutrient. Communicating. Lateral Calcaneal. Muscular Branches.—The peroneal artery, in its course, gives off branches to the Soleus, Tibialis posterior, Flexor hallucis longus, and Peronei. The Nutrient Artery (a. nutricia fibulæ) supplies the fibula, and is directed downward. The Perforating Branch (ramus perforans; anterior peroneal artery) pierces the interosseous membrane, about 5 cm. above the lateral malleolus, to reach the front of the leg, where it anastomoses with the anterior lateral malleolar; it then passes down in front of the tibiofibular syndesmosis, gives branches to the tarsus, and anastomoses with the lateral tarsal. The perforating branch is sometimes enlarged, and takes the place of the dorsalis pedis artery. The Communicating Branch (ramus communicans) is given off from the peroneal about 2.5 cm. from its lower end, and joins the communicating branch of the posterior tibial. The Lateral Calcaneal (ramus calcaneus lateralis; external calcaneal) are the terminal branches of the peroneal artery; they pass to the lateral side of the heel, and communicate with the lateral malleolar and, on the back of the heel, with the medial calcaneal arteries. The nutrient artery (a. nutricia tibiæ) of the tibia arises from the posterior tibial, near its origin, and after supplying a few muscular branches enters the nutrient canal of the bone, which it traverses obliquely from above downward. This is the largest nutrient artery of bone in the body. The muscular branches of the posterior tibial are distributed to the Soleus and deep muscles along the back of the leg. The posterior medial malleolar artery (a. malleolaris posterior medialis; internal malleolar artery) is a small branch which winds around the tibial malleolus and ends in the medial malleolar net-work. The communicating branch (ramus communicans) runs transversely across the back of the tibia, about 5 cm. above its lower end, beneath the Flexor hallucis longus, and joins the communicating branch of the peroneal. The medial calcaneal (rami calcanei mediales; internal calcaneal) are several large arteries which arise from the posterior tibial just before its division; they pierce the laciniate ligament and are distributed to the fat and integument behind the tendo calcaneus and about the heel, and to the muscles on the tibial side of the sole, anastomosing with the peroneal and medial malleolar and, on the back of the heel, with the lateral calcaneal arteries. The medial plantar artery (a. plantaris medialis; internal plantar artery), much smaller than the lateral, passes forward along the medial side of the foot. It is at first situated above the Abductor hallucis, and then between it and the Flexor digitorum brevis, both of which it supplies. At the base of the first metatarsal bone, where it is much diminished in size, it passes along the medial border of the first toe, anastomosing with the first dorsal metatarsal artery. Small superficial digital branches accompany the digital branches of the medial plantar nerve and join the plantar metatarsal arteries of the first three spaces. The lateral plantar artery (a. plantaris lateralis; external plantar artery), much larger than the medial, passes obliquely lateralward and forward to the base of the fifth metatarsal bone. It then turns medialward to the interval between the bases of the first and second metatarsal bones, where it unites with the deep plantar branch of the dorsalis pedis artery, thus completing the plantar arch. As this artery passes lateralward, it is first placed between the calcaneus and Abductor hallucis, and then between the Flexor digitorum brevis and Quadratus plantæ as it runs forward to the base of the little toe it lies more superficially between the Flexor digitorum brevis and Abductor digiti quinti, covered by the plantar aponeurosis and integument. The remaining portion of the vessel is deeply situated; it extends from the base of the fifth metatarsal bone to the proximal part of the first interosseous space, and forms the plantar arch; it is convex forward, lies below the bases of the second, third, and fourth metatarsal bones and the corresponding Interossei, and upon the oblique part of the Adductor hallucis. Branches.—The plantar arch, besides distributing numerous branches to the muscles, integument, and fasciæ in the sole, gives off the following branches: Perforating. Plantar Metatarsal. The Perforating Branches (rami perforantes) are three in number; they ascend through the proximal parts of the second, third, and fourth interosseous spaces, between the heads of the Interossei dorsales, and anastomose with the dorsal metatarsal arteries. The Plantar Metatarsal Arteries (aa. metatarseæ plantares; digital branches) are four in number, and run forward between the metatarsal bones and in contact with the Interossei. Each divides into a pair of plantar digital arteries which supply the adjacent sides of the toes. Near their points of division each sends upward an anterior perforating branch to join the corresponding dorsal metatarsal artery. The first plantar metatarsal artery (arteria princeps hallucis) springs from the junction between the lateral plantar and deep plantar arteries and sends a digital branch to the medial side of the first toe. The digital branch for the lateral side of the fifth toe arise from the lateral plantar artery near the base of the fifth metatarsal bone.
The popliteal artery is the continuation of the femoral, and courses through the popliteal fossa. It extends from the opening in the Adductor magnus, at the junction of the middle and lower thirds of the thigh, downward and lateralward to the intercondyloid fossa of the femur, and then vertically downward to the lower border of the Popliteus, where it divides into anterior and posterior tibial arteries. Relations.—In front of the artery from above downward are the popliteal surface of the femur (which is separated from the vessel by some fat), the back of the knee-joint, and the fascia covering the Popliteus. Behind, it is overlapped by the Semimembranosus above, and is covered by the Gastrocnemius and Plantaris below. In the middle part of its course the artery is separated from the integument and fasciæ by a quantity of fat, and is crossed from the lateral to the medial side by the tibial nerve and the popliteal vein, the vein being between the nerve and the artery and closely adherent to the latter. On its lateral side, above, are the Biceps femoris, the tibial nerve, the popliteal vein, and the lateral condyle of the femur; below, the Plantaris and the lateral head of the Gastrocnemius. On its medial side, above, are the Semimembranosus and the medial condyle of the femur; below, the tibial nerve, the popliteal vein, and the medial head of the Gastrocnemius. The relations of the popliteal lymph glands to the artery are described above. Peculiarities in Point of Division.—Occasionally the popliteal artery divides into its terminal branches opposite the knee-joint. The anterior tibial under these circumstances usually passes in front of the Popliteus. Unusual Branches.—The artery sometimes divides into the anterior tibial and peroneal, the posterior tibial being wanting, or very small. Occasionally it divides into three branches, the anterior and posterior tibial, and peroneal. Branches.—The branches of the popliteal artery are: Muscular
Superior Lateral Superior Genicular. Sural. Middle Genicular. Cutaneous. Medial Inferior Genicular. Medial Superior Genicular Lateral Inferior Genicular. The superior muscular branches, two or three in number, arise from the upper part of the artery, and are distributed to the lower parts of the Adductor magnus and hamstring muscles, anastomosing with the terminal part of the profunda femoris. The sural arteries (aa. surales; inferior muscular arteries) are two large branches, which are distributed to the Gastrocnemius, Soleus, and Plantaris. They arise from the popliteal artery opposite the knee-joint. The cutaneous branches arise either from the popliteal artery or from some of its branches; they descend between the two heads of the Gastrocnemius, and, piercing the deep fascia, are distributed to the skin of the back of the leg. One branch usually accompanies the small saphenous vein. The superior genicular arteries (aa. genu superiores; superior articular arteries), two in number, arise one on either side of the popliteal, and wind around the femur immediately above its condyles to the front of the knee-joint. The medial superior genicular runs in front of the Semimembranosus and Semitendinosus, above the medial head of the Gastrocnemius, and passes beneath the tendon of the Adductor magnus. It divides into two branches, one of which supplies the Vastus medialis, anastomosing with the highest genicular and medial inferior genicular arteries; the other ramifies close to the surface of the femur, supplying it and the knee-joint, and anastomosing with the lateral superior genicular artery. The medial superior genicular artery is frequently of small size, a condition, which is associated with an increase in the size of the highest genicular. The lateral superior genicular passes above the lateral condyle of the femur, beneath the tendon of the Biceps femoris, and divides into a superficial and a deep branch; the superficial branch supplies the Vastus lateralis, and anastomoses with the descending branch of the lateral femoral circumflex and the lateral inferior genicular arteries; the deep branch supplies the lower part of the femur and knee-joint, and forms an anastomotic arch across the front of the bone with the highest genicular and the medial inferior genicular arteries. The middle genicular artery (a. genu media; azygos articular artery) is a small branch, arising opposite the back of the knee-joint. It pierces the oblique popliteal ligament, and supplies the ligaments and synovial membrane in the interior of the articulation. The inferior genicular arteries (aa. genu inferiores; inferior articular arteries), two in number, arise from the popliteal beneath the Gastrocnemius. The medial inferior genicular first descends along the upper margin of the Popliteus, to which it gives branches; it then passes below the medial condyle of the tibia, beneath the tibial collateral ligament, at the anterior border of which it ascends to the front and medial side of the joint, to supply the upper end of the tibia and the articulation of the knee, anastomosing with the lateral inferior and medial superior genicular arteries. The lateral inferior genicular runs lateralward above the head of the fibula to the front of the knee-joint, passing in its course beneath the lateral head of the Gastrocnemius, the fibular collateral ligament, and the tendon of the Biceps femoris. It ends by dividing into branches, which anastomose with the medial inferior and lateral superior genicular arteries, and with the anterior recurrent tibial artery. The Anastomosis Around the Knee-joint.—Around and above the patella, and on the contiguous ends of the femur and tibia, is an intricate net-work of vessels forming a superficial and a deep plexus. The superficial plexus is situated between the fascia and skin around about the patella, and forms three well-defined arches: one, above the upper border of the patella, in the loose connective tissue over the Quadriceps femoris; the other two, below the level of the patella, are situated in the fat behind the ligamentum patellæ. The deep plexus, which forms a close net-work of vessels, lies on the lower end of the femur and upper end of the tibia around their articular surfaces, and sends numerous offsets into the interior of the joint. The arteries which form this plexus are the two medial and the two lateral genicular branches of the popliteal, the highest genicular, the descending branch of the lateral femoral circumflex, and the anterior recurrent tibial The Arteria Dorsalis Pedis (Dorsalis Pedis Artery) The arteria dorsalis pedis, the continuation of the anterior tibial, passes forward from the ankle-joint along the tibial side of the dorsum of the foot to the proximal part of the first intermetatarsal space, where it divides into two branches, the first dorsal metatarsal and the deep plantar. Relations.—This vessel, in its course forward, rests upon the front of the articular capsule of the ankle-joint, the talus, navicular, and second cuneiform bones, and the ligaments connecting them, being covered by the integument, fascia and cruciate ligament, and crossed near its termination by the first tendon of the Extensor digitorum brevis. On its tibial side is the tendon of the Extensor hallucis longus; on its fibular side, the first tendon of the Extensor digitorum longus, and the termination of the deep peroneal nerve. It is accompanied by two veins. Peculiarities in Size.—The dorsal artery of the foot may be larger than usual, to compensate for a deficient plantar artery; or its terminal branches to the toes may be absent, the toes then being supplied by the medial plantar; or its place may be taken altogether by a large perforating branch of the peroneal artery. Position.—This artery frequently curves lateralward, lying lateral to the line between the middle of the ankle and the back part of the first interosseous space. Branches.—The branches of the arteria dorsalis pedis are: Lateral Tarsal. Arcuate. Medial Tarsal. First Dorsal Metatarsal. Deep Plantar. The lateral tarsal artery (a. tarsea lateralis; tarsal artery) arises from the dorsalis pedis, as that vessel crosses the navicular bone; it passes in an arched direction lateralward, lying upon the tarsal bones, and covered by the Extensor digitorum brevis; it supplies this muscle and the articulations of the tarsus, and anastomoses with branches of the arcuate, anterior lateral malleolar and lateral plantar arteries, and with the perforating branch of the peroneal artery. The medial tarsal arteries (aa. tarseæ mediales) are two or three small branches which ramify on the medial border of the foot and join the medial malleolar net-work. The arcuate artery (a. arcuata; metatarsal artery) arises a little anterior to the lateral tarsal artery; it passes lateralward, over the bases of the metatarsal bones, beneath the tendons of the Extensor digitorum brevis, its direction being influenced by its point of origin; and its anastomoses with the lateral tarsal and lateral plantar arteries. This vessel gives off the second, third, and fourth dorsal metatarsal arteries, which run forward upon the corresponding Interossei dorsales; in the clefts between the toes, each divides into two dorsal digital branches for the adjoining toes. At the proximal parts of the interosseous spaces these vessels receive the posterior perforating branches from the plantar arch, and at the distal parts of the spaces they are joined by the anterior perforating branches, from the plantar metatarsal arteries. The fourth dorsal metatarsal artery gives off a branch which supplies the lateral side of the fifth toe. The first dorsal metatarsal artery (a. dorsalis hallucis) runs forward on the first Interosseous dorsalis, and at the cleft between the first and second toes divides into two branches, one of which passes beneath the tendon of the Extensor hallucis longus, and is distributed to the medial border of the great toe; the other bifurcates to supply the adjoining sides of the great and second toes. The deep plantar artery (ramus plantaris profundus; communicating artery) descends into the sole of the foot, between the two heads of the first Interosseous dorsalis, and unites with the termination of the lateral plantar artery, to complete the plantar arch. It sends a branch along the medial side of the great toe, and is continued forward along the first interosseous space as the first plantar metatarsal artery, which bifurcates for the supply of the adjacent sides of the great and second toes.
a) interrogation of the students on the home task; b) study of samples (topic according to the plan); c) fill in the protocol of current lesson; d) checking and signing the protocols by teacher.
Questions: Situational tasks: Tests. 9. The illustrative material: tables, samples. 10. Sources of the information: Human anatomy 11. The program of self-preparation of students: 1. To learn the appropriate sections under the textbook 2. To consider preparations and to study them according to the plan of practical class. 3. To fill in the report of practical class. 4. To be able to show on a preparation of the Common Iliac Arteries, the External Iliac Artery, the Anterior Tibial Artery, the Posterior Tibial Artery, the Popliteal Artery, the Arteria Dorsalis Pedis.
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for foreign first-year students for autumn term Module . Methodical elaboration for practice class on human anatomy for foreign first-year students 1. The topic: The Cavum Oris, the Palate, the Tongue. 2. The place: classroom of the department of human anatomy. 3. The aim: to know the topography and structure of the the Cavum Oris, the Palate and the Tongue. 4. The professional orientation of students: The knowledge of this topic are necessary for doctors of all specialities, it represents special interest for therapists. 5. The basic of knowledge: 6. The plan of the practice class: A. Checking of the home task: interrogation or the test control – 30 min B. Summary lecture on the topic by teacher – 20 min а) Structure of the Cavum oris;
1–palatum durum; 2–palatum mole;
1–papille of the tongue; 2–muscles of the tongue; d) structure of the tongue. C. Self-taught class– 100 min Working plan:
The cavity of the mouth is placed at the commencement of the digestive tube it is a nearly oval-shaped cavity which consists of two parts: an outer, smaller portion, the vestibule, and an inner, larger part, the mouth cavity proper. The Vestibule (vestibulum oris) is a slit-like space, bounded externally by the lips and cheeks; internally by the gums and teeth. It communicates with the surface of the body by the rima or orifice of the mouth. Above and below, it is limited by the reflection of the mucous membrane from the lips and cheeks to the gum covering the upper and lower alveolar arch respectively. It receives the secretion from the parotid salivary glands, and communicates, when the jaws are closed, with the mouth cavity proper by an aperture on either side behind the wisdom teeth, and by narrow clefts between opposing teeth. The Mouth Cavity Proper (cavum oris proprium) is bounded laterally and in front by the alveolar arches with their contained teeth; behind, it communicates with the pharynx by a constricted aperture termed the isthmus faucium. It is roofed in by the hard and soft palates, while the greater part of the floor is formed by the tongue, the remainder by the reflection of the mucous membrane from the sides and under surface of the tongue to the gum lining the inner aspect of the mandible. It receives the secretion from the submaxillary and sublingual salivary glands. Structure.—The mucous membrane lining the mouth is continuous with the integument at the free margin of the lips, and with the mucous lining of the pharynx behind; it is of a rosepink tinge during life, and very thick where it overlies the hard parts bounding the cavity. It is covered by stratified squamous epithelium. The Lips (labia oris), the two fleshy folds which surround the rima or orifice of the mouth, are formed externally of integument and internally of mucous membrane, between which are found the Orbicularis oris muscle, the labial vessels, some nerves, areolar tissue, and fat, and numerous small labial glands. The inner surface of each lip is connected in the middle line to the corresponding gum by a fold of mucous membrane, the frenulum—the upper being the larger. The Labial Glands (glandulœ labiales) are situated between the mucous membrane and the Orbicularis oris, around the orifice of the mouth. They are circular in form, and about the size of small peas; their ducts open by minute orifices upon the mucous membrane. In structure they resemble the salivary glands. The Cheeks (buccæ) form the sides of the face, and are continuous in front with the lips. They are composed externally of integument; internally of mucous membrane; and between the two of a muscular stratum, besides a large quantity of fat, areolar tissue, vessels, nerves, and buccal glands. Structure.—The mucous membrane lining the cheek is reflected above and below upon the gums, and is continuous behind with the lining membrane of the soft palate. Opposite the second molar tooth of the maxilla is a papilla, on the summit of which is the aperture of the parotid duct. The principal muscle of the cheek is the Buccinator; but other muscles enter into its formation, viz., the Zygomaticus, Risorius, and Platysma. The buccal glands are placed between the mucous membrane and Buccinator muscle: they are similar in structure to the labial glands, but smaller. About five, of a larger size than the rest, are placed between the Masseter and Buccinator muscles around the distal extremity of the parotid duct; their ducts open in the mouth opposite the last molar tooth. They are called molar glands. The Gums (gingivœ) are composed of dense fibrous tissue, closely connected to the periosteum of the alveolar processes, and surrounding the necks of the teeth. They are covered by smooth and vascular mucous membrane, which is remarkable for its limited sensibility. Around the necks of the teeth this membrane presents numerous fine papillæ, and is reflected into the alveoli, where it is continuous with the periosteal membrane lining these cavities.
The Hard Palate (palatum durum) is bounded in front and at the sides by the alveolar arches and gums; behind, it is continuous with the soft palate. It is covered by a dense structure, formed by the periosteum and mucous membrane of the mouth, which are intimately adherent. Along the middle line is a linear raphæ, which ends anteriorly in a small papilla corresponding with the incisive canal. On either side and in front of the raphé the mucous membrane is thick, pale in color, and corrugated; behind, it is thin, smooth, and of a deeper color; it is covered with stratified squamous epithelium, and furnished with numerous palatal glands, which lie between the mucous membrane and the surface of the bone. The Soft Palate (palatum molle) is a movable fold, suspended from the posterior border of the hard palate, and forming an incomplete septum between the mouth and pharynx. It consists of a fold of mucous membrane enclosing muscular fibers, an aponeurosis, vessels, nerves, adenoid tissue, and mucous glands. When occupying its usual position, i. e., relaxed and pendent, its anterior surface is concave, continuous with the roof of the mouth, and marked by a median raphé. Its posterior surface is convex, and continuous with the mucous membrane covering the floor of the nasal cavities. Its upper border is attached to the posterior margin of the hard palate, and its sides are blended with the pharynx. Its lower border is free. Its lower portion, which hangs like a curtain between the mouth and pharynx is termed the palatine velum. Hanging from the middle of its lower border is a small, conical, pendulous process, the palatine uvula; and arching lateralward and downward from the base of the uvula on either side are two curved folds of mucous membrane, containing muscular fibers, called the arches or pillars of the fauces. The Tongue (lingua).—The tongue is the principal organ of the sense of taste, and an important organ of speech; it also assists in the mastication and deglutition of the food. It is situated in the floor of the mouth, within the curve of the body of the mandible. Its Root (radix linguæ base) is directed backward, and connected with the hyoid bone by the Hyoglossi and Genioglossi muscles and the hyoglossal membrane; with the epiglottis by three folds (glossoepiglottic) of mucous membrane; with the soft palate by the glossopalatine arches; and with the pharynx by the Constrictores pharyngis superiores and the mucous membrane. Its Apex (apex linguæ tip), thin and narrow, is directed forward against the lingual surfaces of the lower incisor teeth. Its Inferior Surface (facies inferior linguæ under surface) is connected with the mandible by the Genioglossi; the mucous membrane is reflected from it to the lingual surface of the gum and on to the floor of the mouth, where, in the middle line, it is elevated into a distinct vertical fold, the frenulum linguæ. On either side lateral to the frenulum is a slight fold of the mucous membrane, the plica fimbriata, the free edge of which occasionally exhibits a series of fringe-like processes. The apex of the tongue, part of the inferior surface, the sides, and dorsum are free. The Dorsum of the Tongue (dorsum linguæ) is convex and marked by a median sulcus, which divides it into symmetrical halves; this sulcus ends behind, about 2.5 cm. from the root of the organ, in a depression, the foramen cecum, from which a shallow groove, the sulcus terminalis, runs lateralward and forward on either side to the margin of the tongue. The part of the dorsum of the tongue in front of this groove, forming about two-thirds of its surface, looks upward, and is rough and covered with papillæ; the posterior third looks backward, and is smoother, and contains numerous muciparous glands and lymph follicles (lingual tonsil). The foramen cecum is the remains of the upper part of the thyroglossal duct or diverticulum from which the thyroid gland is developed; the pyramidal lobe of the thyroid gland indicates the position of the lower part of the duct. The Papillæ of the Tongue are projections of the corium. They are thickly distributed over the anterior two-thirds of its dorsum, giving to this surface its characteristic roughness. The varieties of papillæ met with are the papillæ vallatæ, papillæ fungiformes, papillæ filiformes, and papillæ simplices. The papillæ vallatæ (circumvallate papillæ) are of large size, and vary from eight to twelve in number. They are situated on the dorsum of the tongue immediately in front of the foramen cecum and sulcus terminalis, forming a row on either side; the two rows run backward and medialward, and meet in the middle line, like the limbs of the letter V inverted. Each papilla consists of a projection of mucous membrane from 1 to 2 mm. wide, attached to the bottom of a circular depression of the mucous membrane; the margin of the depression is elevated to form a wall (vallum), and between this and the papilla is a circular sulcus termed the fossa. The papilla is shaped like a truncated cone, the smaller end being directed downward and attached to the tongue, the broader part or base projecting a little above the surface of the tongue and being studded with numerous small secondary papillæ and covered by stratified squamous epithelium. The papillæ fungiformes (fungiform papillæ) more numerous than the preceding, are found chiefly at the sides and apex, but are scattered irregularly and sparingly over the dorsum. They are easily recognized, among the other papillæ, by their large size, rounded eminences, and deep red color. They are narrow at their attachment to the tongue, but broad and rounded at their free extremities, and covered with secondary papillæ. The papillæ filiformes (filiform or conical papilæ) cover the anterior two-thirds of the dorsum. They are very minute, filiform in shape, and arranged in lines parallel with the two rows of the papillæ vallatæ, excepting at the apex of the organ, where their direction is transverse. Projecting from their apices are numerous filamentous processes, or secondary papillæ these are of a whitish tint, owing to the thickness and density of the epithelium of which they are composed, which has here undergone a peculiar modification, the cells having become cornified and elongated into dense, imbricated, brush-like processes. They contain also a number of elastic fibers, which render them firmer and more elastic than the papillæ of mucous membrane generally. The larger and longer papillæ of this group are sometimes termed papillæ conicæ. The papillæ simplices are similar to those of the skin, and cover the whole of the mucous membrane of the tongue, as well as the larger papillæ. They consist of closely set microscopic elevations of the corium, each containing a capillary loop, covered by a layer of epithelium.
The extrinsic muscles are: Genioglossus. Hyoglossus. Chondroglossus. Styloglossus. Glossopalatinus. The Genioglossus (Geniohyoglossus) is a flat triangular muscle close to and parallel with the median plane, its apex corresponding with its point of origin from the mandible, its base with its insertion into the tongue and hyoid bone. It arises by a short tendon from the superior mental spine on the inner surface of the symphysis menti, immediately above the Geniohyoideus, and from this point spreads out in a fan-like form. The inferior fibers extend downward, to be attached by a thin aponeurosis to the upper part of the body of the hyoid bone, a few passing between the Hyoglossus and Chondroglossus to blend with the Constrictores pharyngis; the middle fibers pass backward, and the superior ones upward and forward, to enter the whole length of the under surface of the tongue, from the root to the apex. The muscles of opposite sides are separated at their insertions by the median fibrous septum of the tongue; in front, they are more or less blended owing to the decussation of fasciculi in the median plane. The Hyoglossus, thin and quadrilateral, arises from the side of the body and from the whole length of the greater cornu of the hyoid bone, and passes almost vertically upward to enter the side of the tongue, between the Styloglossus and Longitudinalis inferior. The fibers arising from the body of the hyoid bone overlap those from the greater cornu. The Chondroglossus is sometimes described as a part of the Hyoglossus, but is separated from it by fibers of the Genioglossus, which pass to the side of the pharynx. It is about 2 cm. long, and arises from the medial side and base of the lesser cornu and contiguous portion of the body of the hyoid bone, and passes directly upward to blend with the intrinsic muscular fibers of the tongue, between the Hyoglossus and Genioglossus. A small slip of muscular fibers is occasionally found, arising from the cartilago triticea in the lateral hyothyroid ligament and entering the tongue with the hindermost fibers of the Hyoglossus. The Styloglossus, the shortest and smallest of the three styloid muscles, arises from the anterior and lateral surfaces of the styloid process, near its apex, and from the stylomandibular ligament. Passing downward and forward between the internal and external carotid arteries, it divides upon the side of the tongue near its dorsal surface, blending with the fibers of the Longitudinalis inferior in front of the Hyoglossus; the other, oblique, overlaps the Hyoglossus and decussates with its fibers. The intrinsic muscles are: Longitudinalis superior. Transversus. Longitudinalis inferior. Verticalis. The Longitudinalis linguæ superior (Superior lingualis) is a thin stratum of oblique and longitudinal fibers immediately underlying the mucous membrane on the dorsum of the tongue. It arises from the submucous fibrous layer close to the epiglottis and from the median fibrous septum, and runs forward to the edges of the tongue. The Longitudinalis linguæ inferior (Inferior lingualis) is a narrow band situated on the under surface of the tongue between the Genioglossus and Hyoglossus. It extends from the root to the apex of the tongue: behind, some of its fibers are connected with the body of the hyoid bone; in front it blends with the fibers of the Styloglossus. The Transversus linguæ (Transverse lingualis) consists of fibers which arise from the median fibrous septum and pass lateralward to be inserted into the submucous fibrous tissue at the sides of the tongue. The Verticalis linguæ (Vertical lingualis) is found only at the borders of the forepart of the tongue. Its fibers extend from the upper to the under surface of the organ. The median fibrous septum of the tongue is very complete, so that the anastomosis between the two lingual arteries is not very free. Nerves.—The muscles of the tongue described above are supplied by the hypoglossal nerve. Actions.—The movements of the tongue, although numerous and complicated, may be understood by carefully considering the direction of the fibers of its muscles. The Genioglossi, by means of their posterior fibers, draw the root of the tongue forward, and protrude the apex from the mouth. The anterior fibers draw the tongue back into the mouth. The two muscles acting in their entirety draw the tongue downward, so as to make its superior surface concave from side to side, forming a channel along which fluids may pass toward the pharynx, as in sucking. The Hyoglossi depress the tongue, and draw down its sides. The Styloglossi draw the tongue upward and backward. The Glossopalatini draw the root of the tongue upward. The intrinsic muscles are mainly concerned in altering the shape of the tongue, whereby it becomes shortened, narrowed, or curved in different directions; thus, the Longitudinalis superior and inferior tend to shorten the tongue, but the former, in addition, turn the tip and sides upward so as to render the dorsum concave, while the latter pull the tip downward and render the dorsum convex. The Transversus narrows and elongates the tongue, and the Verticalis flattens and broadens it. The complex arrangement of the muscular fibers of the tongue, and the various directions in which they run, give to this organ the power of assuming the forms necessary for the enunciation of the different consonantal sounds; and Macalister states “there is reason to believe that the musculature of the tongue varies in different races owing to the hereditary practice and habitual use of certain motions required for enunciating the several vernacular languages.” Structure of the Tongue.—The tongue is partly invested by mucous membrane and a submucous fibrous layer. The mucous membrane (tunica mucosa linguæ) differs in different parts. That covering the under surface of the organ is thin, smooth, and identical in structure with that lining the rest of the oral cavity. The mucous membrane of the dorsum of the tongue behind the foramen cecum and sulcus terminalis is thick and freely movable over the subjacent parts. It contains a large number of lymphoid follicles, which together constitute what is sometimes termed the lingual tonsil. Each follicle forms a rounded eminence, the center of which is perforated by a minute orifice leading into a funnel-shaped cavity or recess; around this recess are grouped numerous oval or rounded nodules of lymphoid tissue, each enveloped by a capsule derived from the submucosa, while opening into the bottom of the recesses are also seen the ducts of mucous glands. The mucous membrne on the anterior part of the dorsum of the tongue is thin, intimately adherent to the muscular tissue, and presents numerous minute surface eminences, the papillæ of the tongue. It consists of a layer of connective tissue, the corium or mucosa, covered with epithelium. The epithelium is of the stratified squamous variety, similar to but much thinner than that of the skin: and each papilla has a separate investment from root to summit. The deepest cells may sometimes be detached as a separate layer, corresponding to the rete mucosum, but they never contain coloring matter. The corium consists of a dense felt-work of fibrous connective tissue, with numerous elastic fibers, firmly connected with the fibrous tissue forming the septa between the muscular bundles of the tongue. It contains the ramifications of the numerous vessels and nerves from which the papillæ are supplied, large plexuses of lymphatic vessels, and the glands of the tongue. Structure of the Papillæ.—The papillæ apparently resemble in structure those of the cutis, consisting of cone-shaped projections of connective tissue, covered with a thick layer of stratified squamous epithelium, and containing one or more capillary loops among which nerves are distributed in great abundance. If the epithelium be removed, it will be found that they are not simple elevations like the papillæ of the skin, for the surface of each is studded with minute conical processes which form secondary papillæ. In the papillæ vallatæ, the nerves are numerous and of large size; in the papillæ fungiformes they are also numerous, and end in a plexiform net-work, from which brush-like branches proceed; in the papillæ filiformes, their mode of termination is uncertain.
The mucous glands are similar in structure to the labial and buccal glands. They are found especially at the back part behind the vallate papillæ, but are also present at the apex and marginal parts. In this connection the anterior lingual glands (Blandin or Nuhn) require special notice. They are situated on the under surface of the apex of the tongue one on either side of the frenulum, where they are covered by a fasciculus of muscular fibers derived from the Styloglossus and Longitudinalis inferior. They are from 12 to 25 mm. long, and about 8 mm. broad, and each opens by three or four ducts on the under surface of the apex. The serous glands occur only at the back of the tongue in the neighborhood of the taste-buds, their ducts opening for the most part into the fossæ of the vallate papillæ. These glands are racemose, the duct of each branching into several minute ducts, which end in alveoli, lined by a single layer of more or less columnar epithelium. Their secretion is of a watery nature, and probably assists in the distribution of the substance to be tasted over the taste area. (Ebner.) The septum consists of a vertical layer of fibrous tissue, extending throughout the entire length of the median plane of the tongue, though not quite reaching the dorsum. It is thicker behind than in front, and occasionally contains a small fibrocartilage, about 6 mm. in length. It is well displayed by making a vertical section across the organ. The hyoglossal membrane is a strong fibrous lamina, which connects the under surface of the root of the tongue to the body of the hyoid bone. This membrane receives, in front, some of the fibers of the Genioglossi.
The sensory nerves of the tongue are: (1) the lingual branch of the mandibular, which is distributed to the papillæ at the forepart and sides of the tongue, and forms the nerve of ordinary sensibility for its anterior two-thirds; (2) the chorda tympani branch of the facial, which runs in the sheath of the lingual, and is generally regarded as the nerve of taste for the anterior two-thirds; this nerve is a continuation of the sensory root of the facial (nervus intermedius); (3) the lingual branch of the glossopharyngeal, which is distributed to the mucous membrane at the base and sides of the tongue, and to the papillæ vallatæ, and which supplies both gustatory filaments and fibers of general sensation to this region; (4) the superior laryngeal, which sends some fine branches to the root near the epiglottis. The Salivary Glands–Three large pairs of salivary glands communicate with the mouth, and pour their secretion into its cavity; they are the parotid, submaxillary, and sublingual. 7. Methodic of class work: a) interrogation of the students on the home task; b) study of samples (topic according to the plan); c) fill in the protocol of current lesson; d) checking and signing the protocols by teacher.
Questions: Situational tasks: Tests. 9. The illustrative material: tables, samples. 10. Sources of the information: Human anatomy 11. The program of self-preparation of students: 1. To learn the appropriate sections under the textbook 2. To consider preparations and to study them according to the plan of practical class. 3. To fill in the report of practical class. 4. To be able to show on a preparation of the Cavum Oris, the Palate, the Tongue.
2. The place: classroom of the department of human anatomy. 3. The aim: to know the structure and topography of the Teeth, the Fauces and the salivary glands. 4. The professional orientation of students: The knowledge of this topic are necessary for doctors of all specialities, it represents special interest for therapists. 5. The basic of knowledge: 6. The plan of the practice class: A. Checking of the home task: interrogation or the test control – 30 min B. Summary lecture on the topic by teacher – 20 min а) the Teeth; b) the Fauces;
1–the parotid gland; 2–the sublingualis gland; 3–the submaxillary gland; C. Self-taught class– 100 min Working plan:
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