State establishment "DnEpropetrovsk Medical Academy of health Ministry of Ukraine"
Download 2.33 Mb.
|
- Navigate this page:
- Nerves.
- Practice class 20. The muscles of the cervical region. The fasciae and spaces of the neck. The aim
- Professional orientation
- Practice class 21. The muscles and fasciae of the abdomen. The inguinal canal. The aim
- Obliquus externus abdominis
Temporal Fascia.—The temporal fascia covers the Temporalis muscle. It is a strong, fibrous investment, covered, laterally, by the Auricularis anterior and superior, by the galea aponeurotica, and by part of the Orbicularis oculi. The superficial temporal vessels and the auriculotemporal nerve cross it from below upward. Above, it is a single layer, attached to the entire extent of the superior temporal line; but below, where it is fixed to the zygomatic arch, it consists of two layers, one of which is inserted into the lateral, and the other into the medial border of the arch. A small quantity of fat, the orbital branch of the superficial temporal artery, and a filament from the zygomatic branch of the maxillary nerve, are contained between these two layers. It affords attachment by its deep surface to the superficial fibers of the Temporalis. The Temporalis (Temporal muscle) is a broad, radiating muscle, situated at the side of the head. It arises from the whole of the temporal fossa (except that portion of it which is formed by the zygomatic bone) and from the deep surface of the temporal fascia. Its fibers converge as they descend, and end in a tendon, which passes deep to the zygomatic arch and is inserted into the medial surface, apex, and anterior border of the coronoid process, and the anterior border of the ramus of the mandible nearly as far forward as the last molar tooth. The Pterygoideus externus (External pterygoid muscle) is a short, thick muscle, somewhat conical in form, which extends almost horizontally between the infratemporal fossa and the condyle of the mandible. It arises by two heads; an upper from the lower part of the lateral surface of the great wing of the sphenoid and from the infratemporal crest; a lower from the lateral surface of the lateral pterygoid plate. Its fibers pass horizontally backward and lateralward, to be inserted into a depression in front of the neck of the condyle of the mandible, and into the front margin of the articular disk of the temporomandibular articulation. The Pterygoideus internus (Internal pterygoid muscle) is a thick, quadrilateral muscle. It arises from the medial surface of the lateral pterygoid plate and the grooved surface of the pyramidal process of the palatine bone; it has a second slip of origin from the lateral surfaces of the pyramidal process of the palatine and tuberosity of the maxilla. Its fibers pass downward, lateralward, and backward, and are inserted, by a strong tendinous lamina, into the lower and back part of the medial surface of the ramus and angle of the mandible, as high as the mandibular foramen. Nerves.—The muscles of mastication are supplied by the mandibular nerve. Actions.—The Temporalis, Masseter, and Pterygoideus internus raise the mandible against the maxillae with great force. The Pterygoideus externus assists in opening the mouth, but its main action is to draw forward the condyle and articular disk so that the mandible is protruded and the inferior incisors projected in front of the upper; in this action it is assisted by the Pterygoideus internus. The mandible is retracted by the posterior fibers of the Temporalis. If the Pterygoidei internus and externus of one side act, the corresponding side of the mandible is drawn forward while the opposite condyle remains comparatively fixed, and side-to-side movements. Such as occur during the trituration of food, take place. Practice skills Students are supposed to identify the following anatomical structures on the samples:
Practice class 20. The muscles of the cervical region. The fasciae and spaces of the neck. The aim: to learn the classification, topography and structure of muscles and fasciae of the neck; to show the points of origin and insertion of different groups of muscles of the neck; to find out the functions of these muscles; to understand the clinical importance of the trigones of neck. Professional orientation: knowledge of this topic is necessary for doctors of all the specialities, especially neuropathologists, neurosurgeons, traumatologists, pediatricians and others. The plan of the practice class:
Neck: muscles, fasciae, triangles, spaces Superfical mm. of the Neck A. Platysma m.
B. Sternocleidomastoid m.
Suprahyoid muscles (Netter plate 24)
Infrahyoid muscles a. sternohyoid m.
b. sternothyroid m.
c. thyrohyoid m.
d. omohyoid m.
Deep Muscles of the Neck
Triangles of the Neck Anterior Triangle (Netter plate 23)
Lateral Triangle borders: sternocleidomastoid m., trapezius m., clavicle
Fasciae and spaces of the neck
Practice skills Students are supposed to identify the following anatomical structures on the samples:
Practice class 21. The muscles and fasciae of the abdomen. The inguinal canal. The aim: to learn the classification, topography and structure of muscles and fasciae of the abdomen; to show the points of origin and insertion of different groups of muscles of the abdomen; to find out the functions of these muscles; to learn the structure of the inguinal canal and find out its contents. Professional orientation: knowledge of this topic is necessary for doctors of all the specialities, especially surgeons, traumatologists, angiosurgeons, urologists. The plan of the practice class:
The muscles of the abdomen may be divided into two groups: (1) the anterolateral muscles; (2) the posterior muscles. 1. THE ANTERO-LATERAL MUSCLES OF THE ABDOMEN—The muscles of this group are: Obliquus externus. Transversus. Obliquus internus. Rectus. Pyramidalis. The Superficial Fascia.—The superficial fascia of the abdomen consists, over the greater part of the abdominal wall, of a single layer containing a variable amount of fat; but near the groin it is easily divisible into two layers, between which are found the superficial vessels and nerves and the superficial inguinal lymph glands. The superficial layer (fascia of Camper) is thick, areolar in texture, and contains in its meshes a varying quantity of adipose tissue. Below, it passes over the inguinal ligament, and is continuous with the superficial fascia of the thigh. In the male, Camper’s fascia is continued over the penis and outer surface of the spermatic cord to the scrotum, where it helps to form the dartos. As it passes to the scrotum it changes its characteristics, becoming thin, destitute of adipose tissue, and of a pale reddish color, and in the scrotum it acquires some involuntary muscular fibers. From the scrotum it may be traced backward into continuity with the superficial fascia of the perineum. In the female, Camper’s fascia is continued from the abdomen into the labia majora. The deep layer (fascia of Scarpa) is thinner and more membranous in character than the superficial, and contains a considerable quantity of yellow elastic fibers. It is loosely connected by areolar tissue to the aponeurosis of the Obliquus externus abdominis, but in the middle line it is more intimately adherent to the linea alba and to the symphysis pubis, and is prolonged on to the dorsum of the penis, forming the fundiform ligament; above, it is continuous with the superficial fascia over the rest of the trunk; below and laterally, it blends with the fascia lata of the thigh a little below the inguinal ligament; medially and below, it is continued over the penis and spermatic cord to the scrotum, where it helps to form the dartos. From the scrotum it may be traced backward into continuity with the deep layer of the superficial fascia of the perineum (fascia of Colles). In the female, it is continued into the labia majora and thence to the fascia of Colles. The Obliquus externus abdominis (External or descending oblique muscle) situated on the lateral and anterior parts of the abdomen, is the largest and the most superficial of the three flat muscles in this region. It is broad, thin, and irregularly quadrilateral, its muscular portion occupying the side, its aponeurosis the anterior wall of the abdomen. It arises, by eight fleshy digitations, from the external surfaces and inferior borders of the lower eight ribs; these digitations are arranged in an oblique line which runs downward and backward, the upper ones being attached close to the cartilages of the corresponding ribs, the lowest to the apex of the cartilage of the last rib, the intermediate ones to the ribs at some distance from their cartilages. The five superior serrations increase in size from above downward, and are received between corresponding processes of the Serratus anterior; the three lower ones diminish in size from above downward and receive between them corresponding processes from the Latissimus dorsi. From these attachments the fleshy fibers proceed in various directions. Those from the lowest ribs pass nearly vertically downward, and are inserted into the anterior half of the outer lip of the iliac crest; the middle and upper fibers, directed downward and forward, end in an aponeurosis, opposite a line drawn from the prominence of the ninth costal cartilage to the anterior superior iliac spine. The aponeurosis of the Obliquus externus abdominis is a thin but strong membranous structure, the fibers of which are directed downward and medialward. It is joined with that of the opposite muscle along the middle line, and covers the whole of the front of the abdomen; above, it is covered by and gives origin to the lower fibers of the Pectoralis major; below, its fibers are closely aggregated together, and extend obliquely across from the anterior superior iliac spine to the public tubercle and the pectineal line. In the middle line, it interlaces with the aponeurosis of the opposite muscle, forming the linea alba, which extends from the xiphoid process to the symphysis pubis. That portion of the aponeurosis which extends between the anterior superior iliac spine and the pubic tubercle is a thick band, folded inward, and continuous below with the fascia lata; it is called the inguinal ligament. The portion which is reflected from the inguinal ligament at the pubic tubercle is attached to the pectineal line and is called the lacunar ligament. From the point of attachment of the latter to the pectineal line, a few fibers pass upward and medialward, behind the medial crus of the subcutaneous inguinal ring, to the linea alba; they diverge as they ascend, and form a thin triangular fibrous band which is called the reflected inguinal ligament. In the aponeurosis of the Obliquus externus, immediately above the crest of the pubis, is a triangular opening, the subcutaneous inguinal ring, formed by a separation of the fibers of the aponeurosis in this situation. The following structures require further description, viz., the subcutaneous inguinal ring, the intercrural fibers and fascia, and the inguinal, lacunar, and reflected inguinal ligaments. THE SUBCUTANEOUS INGUINAL RING (annulus inguinalis subcutaneus; external abdominal ring)—The subcutaneous inguinal ring is an interval in the aponeurosis of the Obliquus externus, just above and lateral to the crest of the pubis. The aperture is oblique in direction, somewhat triangular in form, and corresponds with the course of the fibers of the aponeurosis. It usually measures from base to apex about 2.5 cm., and transversely about 1.25 cm. It is bounded below by the crest of the pubis; on either side by the margins of the opening in the aponeurosis, which are called the crura of the ring; and above, by a series of curved intercrural fibers. The inferior crus (external pillar) is the stronger and is formed by that portion of the inguinal ligament which is inserted into the pubic tubercle; it is curved so as to form a kind of groove, upon which, in the male, the spermatic cord rests. The superior crus (internal pillar) is a broad, thin, flat band, attached to the front of the symphysis pubis and interlacing with its fellow of the opposite side. The subcutaneous inguinal ring gives passage to the spermatic cord and ilioinguinal nerve in the male, and to the round ligament of the uterus and the ilioinguinal nerve in the female; it is much larger in men than in women, on account of the large size of the spermatic cord. Directory: 206 -> ENG -> Other -> Library 206 -> Space Junk: Why Gravity is More Plausible Than You Might Think 206 -> Former eurocamp participants in nba 2010-11 206 -> Cgms-41 nasa-wp-06 11 June 2013 206 -> Ap english Language and Composition Instructor 206 -> How big was the abc computer? How many vacuum tubes were in the abc? 206 -> Parent Handbook Table of Contents Introduction What is Giftedness? 206 -> 2014 Jacob K. Javits Gifted and Talented Students Education Project Abstracts pr/Award # S206A140017 Grantee: University of Connecticut Contact: Catherine A. Little Phone: 860-486-2754 Download 2.33 Mb. Share with your friends:
| ||||||||||||||||||||||||