Gemini muscle. Superior and inferior gemellus muscles. "Superior Gemini" in books

33. Muscle of inspiration People with the so-called. charisma (from the Greek charisma - “gift”, “gift”), capable of creating something extraordinary, are distinguished by a high level of energy. It is also known that their brain consumes more energy than the brain of ordinary people. It's easy

30:20-26 Pharaoh's broken arm

30:20-26 Pharaoh's Broken Muscle At the time of the prophecy (April 587), the population of Jerusalem had already been under siege by Babylonian forces for a year. This prophecy conveys the idea that any hope of deliverance from the Babylonians with the help of a new

How does the air muscle work?

How the Air Muscle Works The air muscle is a long tube shaped like a black plastic sleeve. A soft rubber tube is placed inside the sleeve. There are metal clips attached to each end. Each end of the plastic sleeve is folded into

Gemini inferior muscle. Function: these muscles rotate the thigh outward.

Iliopsoas muscle consists of the iliacus and psoas major muscles. Function: flexes the thigh at the hip joint.

Piriformis muscle originates from the pelvic surface of the sacrum, attaching to the top of the greater trochanter. Function: rotates the thigh outward.

External group of pelvic muscles.

Tensor fascia lata originates from the superior anterior ilium, attaching to the lateral condyle of the tibia; at the border of the upper and middle third of the body of the femur it passes into the iliotibial tract. Function: flexes the thigh, strains the iliotibial tract.

Gluteus maximus muscle originates from the iliac crest, sacrotuberous ligament, dorsal surfaces of the sacrum and coccyx, attaching to the gluteal tuberosity of the femur. Function: extends the hip; the posterior inferior bundles adduct and rotate the thigh outward, the anterior superior bundles abduct the thigh and hold the knee joint in an extended position.

Gluteus medius muscle originates from the gluteal surface of the ilium and fascia lata, attaching to the outer surface and the apex of the greater trochanter. Function: abducts the thigh, the posterior bundles turn the thigh outward, the anterior bundles turn the thigh inward.

Quadratus femoris originates from the upper part of the outer edge of the ischial tuberosity, attaching to the upper part of the intertrochanteric ridge. Function: rotates the thigh outward.

Gluteus minimus) originates from the outer surface of the wing of the ilium, attaching to the anterior outer surface of the greater trochanter of the femur. Function: abducts the thigh, the posterior bundles turn the thigh outward, the anterior bundles turn the thigh inward.

Obturator externus muscle originates from the branch of the ischium and the outer surface of the pubis, attaching to the trochanteric fossa of the femur and the articular capsule. Function: rotates the thigh outward.

33. Characteristics of the muscles of the lower limb.

Characteristics of the muscles of the lower limb.The thigh muscles include the medial, anterior and posterior groups.

Medial muscle group of the thigh.

Adductor longus muscle originates from the outer surface of the pubic bone, attaching to the medial lip of the linea aspera of the femur. Function: adducts the hip, turning and bending it outward.

Adductor brevis muscle originates from the outer surface of the body and the lower ramus of the pubis, attaching to the line aspera on the body of the femur. Function: adducts and flexes the thigh.

Adductor magnus muscle originates from the branches and tuberosity of the ischium and the inferior ramus of the pubis, attaching to the medial lip of the linea aspera of the femur. Function: adducts and extends the thigh.

Thin muscle originates from the lower branch of the pubic bone and the lower half of the pubic symphysis, attaching to the medial surface of the upper part of the tibia. Function: adducts the thigh, flexes and rotates the tibia medially.

Pectineus muscle originates from the superior ramus and crest of the pubis, attaching to the area located between the linea aspera of the femur and the posterior surface of the lesser trochanter. Function: adducts and flexes the hip.

Anterior thigh muscle group.

Quadriceps femoris consists of four muscles: the medial, lateral and intermedius muscles of the thigh and the rectus femoris. Function: extends the lower leg at the knee joint (the rectus muscle flexes the thigh).

Sartorius originates from the superior anterior iliac spine, attaching to the tibial tuberosity and fascia of the leg. Function: flexes and rotates the thigh outward, flexes the lower leg.

Posterior thigh muscle group.

Semitendinosus muscle originates from the ischial tuberosity, attaching to the medial surface of the upper part of the tibia. Function: flexes the tibia and extends the thigh.

Semimembranosus muscle originates from the ischial tuberosity, attaching in three bundles to the posterolateral surface of the medial condyle of the tibia. Function: flexes the tibia and extends the thigh.

Biceps femoris consists of short and long heads. Function: flexes the lower leg at the knee joint and extends the thigh.

Lateral muscle group of the lower leg.

Peroneus brevis muscle originates from the lower two-thirds of the lateral surface of the fibula, attaching to the base of the fifth metatarsal bone. Function: raises the lateral edge of the foot, flexes the foot.

Peroneus longus muscle originates from the head and upper two-thirds of the lateral surface of the fibula, the lateral condyle of the tibia, attaching to the base of the first and second metatarsals and the medial cuneiform bone. Function: raises the lateral edge of the foot, flexes the foot, strengthens the longitudinal and transverse arches of the foot.

Anterior group of muscles of the lower leg.

Extensor hallucis longus originates from the middle third of the anterior surface of the body of the fibula, attaching to the distal phalanx of the big toe. Function: extends the big toe.

Tibialis anterior muscle originates from the upper half of the lateral surface of the body and the lateral condyle of the tibia, attaching to the base of the first metatarsal bone and to the plantar surface of the medial wedge-shaped bone. Function: strengthens the longitudinal arch of the foot, extends the foot at the ankle joint with simultaneous supination and elevation of the medial edge.

Extensor digitorum longus originates from the anterior surface of the body of the fibula, the lateral condyle of the tibia and the fascia of the tibia, attaching to the base of the middle and distal phalanges of the II-V fingers. The third peroneal muscle extends from the lower part of this muscle. Function: extends the II-V fingers at the metatarsophalangeal joints and the foot at the ankle joint (the third peroneal muscle raises the lateral edge of the foot).

.Posterior muscle group of the lower leg. Deep layer of muscles.

Flexor digitorum longus originates from the posterior surface of the body of the tibia, the fascia of the leg and the posterior intermuscular septum of the leg, attaching to the distal phalanges of the II-V fingers. Function: flexes and rotates the foot outward and bends the distal phalanges of the II-V fingers.

Flexor pollicis longus originates from the lower two-thirds of the body of the fibula and the intermuscular septum of the leg, attaching to the distal phalanx of the big toe. Function: flexes the big toe, strengthens the longitudinal arch of the foot, participates in supination, flexion and adduction of the foot.

Hamstring muscle originates from the outer surface of the lateral femoral condyle, attaching to the posterior surface of the tibia above the line of the soleus muscle. Function: flexes the tibia, tightens the capsule of the knee joint.

Tibialis posterior muscle originates from the posterior surface of the body of the fibula, the lower surface of the lateral condyle and the upper two-thirds of the body of the tibia, the interosseous membrane, attaching to all three cuneiform bones, the base of the IV metatarsal and the tuberosity of the navicular bone. Function: flexes, supinates and adducts the foot.

Superficial layer of muscles.

Plantaris muscle originates on the lateral epicondyle of the femur and from the oblique popliteal ligament, attaching to the calcaneal tubercle. Function: participates in flexion of the foot and lower leg, stretches the capsule of the knee joint.

Triceps surae muscle consists of the soleus and gastrocnemius muscles.

Soleus muscle originates from the posterior surface of the tibia and the tendinous arch, attaching to the calcaneal tubercle as part of the calcaneal tendon.

Calf muscle originates above the lateral condyle on the outer surface of the lower epiphysis of the femur (its lateral head is located here) and the medial condyle of the femur (its medial head is located here), attaching as part of the calcaneal tendon to the calcaneal tubercle. Function: flexion of the lower leg and foot; with a fixed foot, it holds the tibia on the talus.

34. Characteristics of the masticatory and facial muscles of the head.

Characteristics of the masticatory and facial muscles of the head. The facial muscles of the head are divided into the muscles of the cranial vault, the muscles surrounding the nasal openings, the muscles surrounding the oral fissure, the muscles surrounding the palpebral fissure, and the muscles of the auricle. The muscles of the cranial vault are formed by the supracranial muscle, which consists of three parts: the occipitofrontal muscle, the supracranial aponeurosis and the temporoparietal muscle.

Occipitofrontal muscle consists of an occipital abdomen and a frontal abdomen, which are connected through the supracranial aponeurosis.

Temporoparietal muscle(originates on the inner side of the cartilage of the auricle, attaching to the lateral part of the tendon helmet. Function: the occipital belly pulls the scalp back, the frontal belly pulls the skin of the forehead upward, raising the eyebrows.

Muscle of the proud originates on the outer surface of the nasal bone, ending in the skin of the forehead. Function: straightens transverse folds on the forehead, forms transverse folds at the root of the nose.

Muscles surrounding the nasal openings.

Depressor septum muscle originates above the medial incisor of the upper jaw, attaching to the cartilaginous part of the nasal septum. Function: lowers the nasal septum.

Nasalis muscle consists of two parts: 1) the wing part originates on the upper jaw, woven into the skin of the wing of the nose. Function: expands the openings of the nose, pulls the wing of the nose laterally and downward. 2) the transverse part originates on the upper jaw and passes into the muscle of the same name on the opposite side. Function: narrows the openings of the nose. Innervation: n. facialis.

Muscles surrounding the oral cavity.

Orbicularis oris muscle consists of labial and marginal parts. Function: participates in the act of chewing and sucking, closes the oral fissure.

Depressor labii muscle originates from the base of the lower jaw, attaching to the skin and mucous membrane of the lower lip. Function: pulls the lower lip down.

Levator labii muscle originates from the infraorbital margin of the upper jaw, passing into the muscle that lifts the angle of the mouth and the wing of the nose. Function: raises the upper lip.

Depressor anguli oris muscle originates from the base of the lower jaw, attaching to the skin of the corner of the mouth. Function: lowers the corner of the mouth downwards and laterally.

Levator anguli oris muscle originates from the anterior surface of the upper jaw, attaching to the corner of the mouth. Function: raises the corner of the mouth.

Zygomatic major muscle originates from the zygomatic bone, attaching to the corner of the mouth. Function: pulls the corner of the mouth upward and outward.

Zygomatic minor muscle originates from the zygomatic bone, attaching to the skin of the corner of the mouth. Function: raises the corner of the mouth.

Mentalis muscle originates from the alveolar eminences of the medial and lateral incisors of the lower jaw, attaching to the skin of the chin. Function: pulls the skin of the chin upward and laterally.

Buccal muscle originates from the branch of the lower jaw, the outer surface of the alveolar arch of the upper jaw, passing into the thickness of the base of the lower and upper lips.

Function: presses the cheek to the lips, pulls the corner of the mouth back.

Laughter muscle originates from the masticatory fascia, attaching to the skin of the corner of the mouth. Function: pulls the corner of the mouth laterally.

Muscles surrounding the palpebral fissure.

Corrugator muscle originates from the medial segment of the brow ridge, attaching to the skin of the eyebrow on the same side. Function: pulls the skin of the forehead down and medially.

Orbicularis oculi muscle consists of orbital, lacrimal and eyelid parts. Function: is a sphincter of the palpebral fissure. The lacrimal part expands the lacrimal sac, the eyelid part closes the eyelids, the orbital part forms folds from the outer corner of the eye, pulls the skin of the cheek up, and shifts the eyebrow down.

The masticatory muscle consists of deep and superficial parts. Function: raises the lower jaw, pushes the lower jaw forward.

Medial pterygoid muscle originates in the pterygoid fossa of the sphenoid bone, attaching to the tuberosity of the same name on the upper surface of the angle of the lower jaw. Function: raises the lower jaw, pushes the lower jaw forward.

Lateral pterygoid muscle starts from the lateral plate of the pterygoid process of the sphenoid bone (lower head) and from the maxillary surface and infratemporal crest of the greater wing of the sphenoid bone (its upper head is located here), attaching to the articular capsule of the temporomandibular joint and the anterior surface of the neck of the lower jaw. Function: extends the lower jaw the jaw forward with symmetrical contraction; with unilateral contraction, the lower jaw shifts to the opposite side.

Temporalis muscle originates from the surface of the temporal fossa and the inner surface of the temporal fascia, attaching to the coronoid process of the lower jaw. Function: raises the lower jaw, pulls the jaw forward backward.

35. Muscles of inspiration. Muscles of exhalation. Types of breathing: chest and abdominal. Diaphragm.

Muscles of inspiration.The main muscles of inspiration are:

1) the diaphragm, the contraction of which causes a flattening of its dome and at the same time an increase in the volume of the thoracic cavity in the vertical direction;

2) external and internal intercostal muscles; the former have a larger force arm and a greater torque when inhaling, and the latter, on the contrary, when exhaling;

3) muscles that lift the ribs;

4) top rear serratus muscle;

5) inferior posterior serratus muscle (during diaphragmatic and full breathing);

6) quadratus lumborum muscle (under the same condition);

7) iliocostal muscle (under the same condition);

The accessory muscles of inhalation are:

1) scalene muscles - anterior, middle and posterior (with a fixed cervical part of the spinal column);

2) sternocleidomastoid muscle (with a fixed head);

3) pectoralis minor muscle (with a fixed upper limb belt);

4) subclavian (under the same condition);

5) the pectoralis major muscle with its lower part (with the humerus fixed);

6) lower bundles of the serratus anterior muscle (with a fixed scapula);

7) anterior neck muscles - sternohyoid, sternothyroid, etc. (with a fixed hyoid bone)

Muscles of exhalation. The muscles that work during exhalation are:

1) abdominal muscles are direct antagonists of the diaphragm:

2) internal and external intercostal;

3) subcostal;

4) transverse thoracic muscle;

5) serratus posterior inferior muscle;

6) quadratus lumborum muscle;

7) iliocostal muscle.

Types of breathing: chest and abdominal. For breast type breathing is provided mainly by the work of the intercostal muscles, and the diaphragm moves passively in accordance with changes in intrathoracic pressure.

For abdominal type breathing as a result of a powerful contraction of the diaphragm not only decreases intrapleural pressure, but also simultaneously increases intra-abdominal pressure. This type of breathing is more effective, since it ventilates the lungs more strongly and facilitates the venous return of blood from the abdominal organs to the heart.

Diaphragm. The structure of the diaphragm.

Diaphragm is a mobile muscle-tendon septum that separates the thoracic and abdominal cavities. The diaphragm is divided into a tendon center, in which there is an opening for the inferior vena cava, and three parts: costal, sternal and lumbar. In the lumbar part there is an aortic opening, limited by the right and left legs of the diaphragm, and an esophageal opening. Function: when the diaphragm contracts, the volume of the thoracic cavity increases and the abdominal cavity decreases; with simultaneous contraction of the abdominal muscles, an increase in intra-abdominal pressure occurs.

36. Anatomical characteristics of the organs of the digestive system. Stomach, its position, structure, functions.

Anatomical characteristics of the organs of the digestive system Digestion is a physiological process through which food undergoes physical and chemical transformations, after which nutrients are absorbed from the digestive tract and enter the blood and lymph.

The digestive tract carries out the following functions: secretory, motor, absorption, excretory.

Secretory function consists in the formation by glandular cells of digestive juices containing enzymes that break down proteins, fats, and carbohydrates.

Motor function carried out by the muscles of the digestive tract and ensures chewing, swallowing, movement of food along the digestive tract and absorption of undigested residues.

Suction carried out by the mucous membrane of the stomach, small and large intestines. This process ensures the entry of digested organic substances, salts, vitamins and water into the internal environment of the body.

Excretory function manifested by the release of substances from the internal environment into the lumen of the gastrointestinal tract, which takes part in maintaining acid-base and water-salt balance.

Stomach, its position, structure, functions. The stomach is located in the upper part of the abdominal cavity - most of it lies to the left of the midline of the body and only a small part - to the right. The shape, volume, size, position of the stomach is not constant: they depend on the physique, filling with gases, food, on the tone of the muscles of the stomach, on nervous and hormonal influences, as well as the size and position of neighboring organs. The average capacity of the stomach is 1-3 liters. The stomach consists of the following sections: 1) the cardiac part, adjacent to the place where the esophagus enters the stomach; 2) the bottom, also called the dome; 3) body of the stomach; 4) the pyloric part, consisting of the vestibule and the pyloric canal, ending with the pylorus (Fig. 2). The latter connects the lumen of the stomach with the duodenum.
There is a lesser curvature of the stomach, facing to the right and up, and a greater, facing to the left and down. The wall of the stomach consists of three membranes: serous, muscular and mucous.

Outer serous membrane It is a part of the peritoneum, the leaves of which pass from neighboring organs. Underneath it there is a thin layer of connective tissue - the subserosal layer, in which blood and lymphatic vessels and a nerve plexus lie. At the junction of the serous membrane with neighboring organs, ligaments are formed that support the stomach in a certain position.
Muscular lining of the stomach consists of three layers of smooth muscle. The outer layer is formed by longitudinal fibers, the middle - circular and the inner - oblique; the middle layer thickens at the pylorus, forming the sphincter of the pylorus. Between the muscle layers is the intermuscular nerve plexus (Auerbach).
Mucous membrane The stomach is loosely connected to the muscular submucosal layer and forms folds that have a variety of directions. The submucosal layer contains plexuses of blood and lymphatic vessels and the submucosal nerve plexus (Meissner).
The mucous membrane of the stomach is covered with a kind of columnar epithelium. Millions of excretory ducts of specific tubular glands open into it, which contain four types of cells: main, accessory, parietal and intermediate. The main cells secrete pepsinogen, which is converted into pepsin in an acidic environment, additional and intermediate cells - mucin, parietal cells - hydrochloric acid. The blood supply to the stomach is carried out by the right and left gastric and right and left gastroepiploic arteries. The veins follow the course of the arteries and empty into the portal vein. The draining lymphatic vessels are mainly directed to the gastric lymph nodes located at the greater and lesser curvature of the stomach.

Main functions The stomach is the chemical and physical processing of food received from the oral cavity, the accumulation of chyme and its gradual evacuation into the intestine. It also takes part in intermediate metabolism, excreting metabolic products, including protein metabolism products, which, after hydrolysis, are absorbed and then utilized by the body. The stomach plays a major role in hematopoiesis, in water-salt metabolism and maintaining a constant pH in the blood.

Motor activity of the stomach ensures the deposition of food, its mixing with gastric juice and movement - portioned evacuation into the duodenum.

37. Pancreas, its position, structure, functions.

Pancreas, its position, structure, functions. pancreas- This is a fairly large gland, which is located on the back wall of the abdomen behind the stomach.

The pancreas consists of three main parts:

1) the head, which occupies the main part and has the shape of a hook process,

2) a body shaped like a prism, separated from the head by a small groove,

3) a tail, which can be bent up or slightly down.

Functions. The pancreas is the main source of enzymes for the digestion of fats, proteins and carbohydrates - mainly trypsin and chymotrypsin, pancreatic lipase and amylase. The main pancreatic secretion of duct cells also contains bicarbonate ions, which are involved in the neutralization of acidic gastric chyme. Pancreatic secretions accumulate in the interlobular ducts, which merge with the main excretory duct, which opens into the duodenum.

Interspersed between the lobules are numerous groups of cells that do not have excretory ducts - the so-called. islets of Langerhans. Islet cells function as endocrine glands, releasing glucagon and insulin, hormones that regulate carbohydrate metabolism, directly into the bloodstream. These hormones have the opposite effect: glucagon increases and insulin decreases blood glucose levels.

Proteolytic enzymes are secreted into the lumen of the acinus in the form of zymogens (proenzymes, inactive forms of enzymes) - trypsinogen and chymotrypsinogen. When released into the intestine, they are exposed to the action of enterokinase present in the parietal mucus, which activates trypsinogen, converting it into trypsin. Free trypsin further breaks down the remaining trypsinogen and chymotrypsinogen into their active forms. The formation of enzymes in an inactive form is an important factor in preventing enzyme damage to the pancreas, often observed in pancreatitis.

Hormonal regulation of the exocrine function of the pancreas is ensured by gastrin, cholecystokinin and secretin - hormones produced by the cells of the stomach and duodenum in response to stretching, as well as the secretion of pancreatic juice. Damage to the pancreas poses a serious danger. Pancreatic puncture requires special care when performed.

38. Liver, its position, structure, functions.

The liver consists of two lobes: right and left. In the left lobe, two more secondary lobes are distinguished: quadrate and caudate. According to the modern segmental scheme proposed by Claude Quinot (1957), the liver is divided into eight segments, forming the right and left lobes. The liver segment is a pyramidal section of the hepatic parenchyma, which has a fairly separate blood supply, innervation and bile outflow. The caudate and quadrate lobes, located posterior and anterior to the porta hepatis, according to this scheme correspond to SI and SIV of the left lobe. In addition, in the left lobe, SII and SIII of the liver are distinguished, the right lobe is divided into SV - SVIII, numbered around the gate of the liver in a clockwise direction.

Functions. 1) neutralization of various foreign substances (xenobiotics), in particular allergens, poisons and toxins, by converting them into harmless, less toxic or easier to remove compounds from the body;

2) neutralization and removal from the body of excess hormones, mediators, vitamins, as well as toxic intermediate and final metabolic products, such as ammonia, phenol, ethanol, acetone and ketonic acids;

3) participation in digestive processes, namely providing the body’s energy needs with glucose, and converting various energy sources (free fatty acids, amino acids, glycerol, lactic acid, etc.) into glucose (so-called gluconeogenesis);

4) replenishment and storage of quickly mobilized energy reserves in the form of glycogen depots and regulation of carbohydrate metabolism;

5) replenishment and storage of the depot of some vitamins (the reserves of fat-soluble vitamins A, D, and water-soluble vitamin B12 are especially large in the liver), as well as the depot of cations of a number of microelements - metals, in particular cations of iron, copper and cobalt. The liver is also directly involved in the metabolism of vitamins A, B, C, D, E, K, PP and folic acid;

6) participation in the processes of hematopoiesis (only in the fetus), in particular the synthesis of many blood plasma proteins - albumins, alpha and beta globulins, transport proteins for various hormones and vitamins, proteins of the coagulation and anticoagulation systems of the blood and many others; the liver is one of the important organs of hematopoiesis in prenatal development;

7) synthesis of cholesterol and its esters, lipids and phospholipids, lipoproteins and regulation of lipid metabolism;

8) synthesis of bile acids and bilirubin, production and secretion of bile;

also serves as a depot for a fairly significant volume of blood, which can be released into the general vascular bed during blood loss or shock due to narrowing of the vessels supplying the liver;

9) synthesis of hormones and enzymes that are actively involved in the transformation of food in the duodenum and other parts of the small intestine;

10) in the fetus, the liver performs a hematopoietic function. The detoxification function of the fetal liver is insignificant, since it is performed by the placenta.

39. Small and large intestine, sections, differences in the structure of the wall. Peritoneum.

Small intestine- a section of the intestine in vertebrates, located between the stomach and large intestine. The small intestine performs the main function of absorbing nutrients from chyme in the animal body. The relative length and structural features of the small intestine largely depend on the type of nutrition of the animal.

Sections of the small intestine:

Duodenum- the initial section of the small intestine in humans, immediately following the pylorus of the stomach. The characteristic name is due to the fact that its length is approximately twelve diameters of a finger. The duodenum is closely anatomically and functionally connected with the pancreas and gall bladder. On the inner surface of the descending part of the duodenum there is a large duodenal papilla (papilla of Vater), into which, through the sphincter of Oddi, the common bile duct and the pancreatic duct open (in most, but not all people, it flows into the common bile duct, but in some comes separately). Above the papilla of Vater, 8-40 mm, there may be a small duodenal papilla, through which the additional (Santorini) pancreatic duct opens (this structure is anatomically variable). The duodenum has a special histological structure of the mucosa, making its epithelium more resistant to the aggressiveness of both gastric acid and pepsin, and concentrated bile and pancreatic enzymes than the epithelium of more distal parts of the small intestine. The structure of the epithelium of the duodenum also differs from the structure of the epithelium of the stomach.

Human jejunum- the middle section of the small intestine, coming after the duodenum and passing into the ileum. The name “skinny” comes from the fact that when dissecting a corpse, anatomists found it empty. The jejunum is a smooth muscle hollow organ. The wall of the jejunum contains two layers of muscle tissue: the outer longitudinal and the inner circular. In addition, smooth muscle cells are present in the intestinal mucosa. Loops of jejunum are located in the left upper part of the abdominal cavity. The jejunum is covered on all sides by peritoneum. The jejunum, unlike the duodenum, has a well-defined mesentery and is considered (together with the ileum) as the mesenteric part of the small intestine. It is separated from the duodenum by the duodenojejunal L-shaped fold of Treitz by the duodenojejunal sphincter. There is no clearly defined anatomical structure separating the jejunum and ileum. However, there are clear differences between these two sections of the small intestine: the ileum has a larger diameter, its wall is thicker, and it is richer in blood vessels. The jejunal loops lie primarily to the left of the midline, and the ileal loops lie primarily to the right of the midline. The mesenteric part of the small intestine is covered in front for a greater or lesser extent by the omentum.

Human ileum- the lower section of the small intestine, coming after the jejunum and in front of the upper section of the large intestine - the cecum, separated from the latter by the ileocecal valve (bauginian valve). The ileum is a smooth muscle hollow organ. The wall of the ileum contains two layers of muscle tissue: the outer longitudinal and the inner circular. In addition, smooth muscle cells are present in the intestinal mucosa. The ileum is located in the lower right part of the abdominal cavity and in the area of ​​the right iliac fossa flows into the cecum. The ileum is covered on all sides by peritoneum. The ileum, unlike the duodenum, has a well-defined mesentery and is considered (together with the jejunum) as the mesenteric part of the small intestine. There is no clearly defined anatomical structure separating the ileum and jejunum. However, there are clear differences between these two sections of the small intestine: the ileum has a larger diameter, its wall is thicker, and it is richer in blood vessels. The jejunal loops lie primarily to the left of the midline, and the ileal loops lie primarily to the right of the midline.

Colon- the lower, final part of the digestive tract, namely the lower part of the intestine, in which water is mainly absorbed and formed feces are formed from food gruel (chyme). It is a derivative of the hindgut.

Sections of the colon:

cecum is a sac 3-8.5 cm long, located in the right iliac region, below the junction of the small intestine into the large intestine. A vermiform appendix (appendix) extends from it. At the junction of the small and large intestines there is an ileocecal valve, which prevents the reverse outflow of food masses from the large intestine to the small intestine. At the border of the cecum and colon, the Busi sphincter is located. The cecum is most often covered with peritoneum on all sides and is located intraperitoneally, but it can also lie mesoperitoneally, that is, be covered with peritoneum on three sides. From its edonemedial wall, 0.5-5 cm below the ileocecal angle formed by the confluence of the ileum into the cecum, a vermiform appendix (appendix) extends. It is a narrow tube with a diameter of 3-4 mm, a length of 2.5 to 15 cm. The lumen of the appendix communicates with the lumen of the cecum. The process has its own mesentery, mesoappendix, connecting it with the wall of the cecum and the terminal (terminal) part of the ileum. Usually the appendix lies in the right iliac fossa; its free end faces down and medially, reaches the border line (linea terminalis) and sometimes descends into the small pelvis. However, this position is not constant for all people: the appendix can be located, for example, behind the cecum, being covered and fixed to it by the peritoneum, or in its mesoperitoneal position, even lie extraperitoneally.

colon the main part of the large intestine, a continuation of the cecum. The continuation of the colon is the rectum. The colon is not directly involved in digestion. But it absorbs a large amount of water and electrolytes. The relatively liquid chyme that passes from the small intestine (through the cecum) into the colon is converted into harder feces. The length of the colon is about 1.5 m (including, approximately: the length of the ascending colon - 24 cm, the transverse colon - 56 cm , descending - 22 cm and sigmoid colon - 47 cm). The internal diameter of the colon is from 5 to 8 cm. The Busi sphincter is located at the border of the colon and cecum.

ascending colon- the initial section of the colon (which, in turn, is a section of the large intestine), a continuation of the cecum. A further continuation of the ascending colon is the transverse colon. The ascending colon is not directly involved in digestion. Its functions. like other parts of the large intestine, they involve the absorption of water and electrolytes so that the relatively liquid chyme that passes from the small intestine to the large intestine is converted into thicker feces. The ascending colon is located on the right side of the abdominal cavity. Her position is not permanent. In an upright position of the body, the initial part of the ascending colon is directed upward, continuing the cecum. The area where the ascending colon enters the transverse colon is called the right (hepatic) flexure of the colon. The ascending colon is covered in front and on the sides by peritoneum. The length of the ascending colon is about 24 cm. The internal diameter of the colon is about 7 cm. At the border of the ascending colon and cecum there is the Busy sphincter (synonyms: colocecal Busy sphincter, cecal ascending sphincter

transverse colon section of the colon (section of the large intestine, see item 2 in the figure), a continuation of the ascending colon. A further continuation of the transverse colon is the descending colon. The transverse colon is not directly involved in digestion. Its functions, like other parts of the large intestine, are to absorb water and electrolytes so that the relatively liquid chyme that passes from the small intestine to the large intestine is converted into thicker feces. In the region of the right hypochondrium, at the level of the X costal cartilage, the ascending colon forms a bend to the left and forward and passes into the transverse colon (this area of ​​​​transition is called the right or hepatic flexure of the colon). Next, the transverse colon runs in an oblique direction from right to left, first down, then up to the region of the left hypochondrium. In an upright position of the body, the transverse colon most often sags downwards in an arcuate manner. In the left hypochondrium, at the level of the IX costal cartilage, in an area called the left or splenic flexure of the colon, the transverse colon passes into the descending colon. The transverse colon is covered on all sides by peritoneum. The intestine is attached to the posterior wall of the abdominal cavity using the mesentery. The length of the transverse colon is 25 - 62 cm, on average 50 cm. The internal diameter of the intestine is about 6-7 cm.

descending colon third section of the colon (which, in turn, is a section

The twin muscles belong to the outer group of the pelvic muscles. Their function is, together with the obturator internus muscle, to abduct the thigh outward. They begin at the top and bottom of the ischium, connecting it to the greater trochanter. Together with the rest of the pelvic muscles, they experience enormous daily stress, ensuring human motor activity.

Anatomy of the superior and inferior gemellus muscles

It is recommended to begin sports, especially those related to bodybuilding, by studying the anatomy of the underlying skeletal muscles. It is divided into several parts according to affiliation. The muscles of the lower extremities and pelvis, which ensure that the torso is held in an upright position and various types of movement, are considered together. Many of them are paired.

The superior and inferior gemellus pelvic muscles share the same flat shape. They look like an elongated triangle, the wide side of which is located on the ischium, and the narrow side is directed towards the greater trochanter. Latin name Musculus gemellus. The word "gemelus" means twin, duplication. Muscles act in pairs. The twin muscles of the thigh are located in the buttocks area, covered on top by an outer layer of muscles.

Examining the structure of the organ, one can notice bundles of striated fibers. Each of them is a separate structural unit capable of contraction. A fiber is a multinucleated cell in a membrane. Its main components are water and proteins, which provide contraction. The fibers are collected in muscle bundles and separated by layers of connective tissue. Sympathetic nerves that transmit impulses approach them. The muscle is divided into two parts:

• abdomen - the active half, capable of contracting;
• tendon is the passive part responsible for tension.

The strength of a muscle depends on the number of muscle fibers. Muscles are classified according to several criteria. Regarding musculus gemellus:

• in the direction of the fibers - straight;
• function – rotation (rotational);
• the form is short and simple.

The coherence of muscle function depends on the health of each link in the chain: brain-nerve-muscle.

Start

Superior gemellus muscle or m. gemellus superior starts from the ischial spine. The ischium is located in the lower part of the pelvis, articulates with the ilium and pubis. On the back surface of her body there is a small protrusion - the ischial spine. At the bottom of the bone there is a thickening with a rough surface - the ischial tubercle. This is the site of the beginning of the inferior gemellus muscle m. gemellus inferior.

Attachment

Both twin muscles have one point of attachment - the upper part of the femur in the area of ​​the trochanteric fossa. The distal ends of the cords connect to the short tendon of the obturator internus muscle, which leaves the pelvis. Both musculus gemellus are its synergists. The superior gemellus muscle supports the locking muscle, which loses some of its strength when changing direction at the sciatic notch. Based on their close arrangement and joint action, they were previously called the triceps muscle.

Innervation

The pelvis is penetrated by a large number of nerve endings and blood vessels. They provide nutrition and activity to skeletal muscles. The connection between the organ and the central nervous system occurs through several peripheral nerves:

• ventral branch of the lumbar nerve L5;
• sacral plexus nerves S1, S2;
• partially innervates the internal obturator nerve of the sacral plexus, which arises from the anterior branch.

Nerve impulses are sent to create motor activity. In addition, they have a vegetative function - they regulate the metabolic processes of the muscles. Control is carried out by motor neurons, which form motor units with muscle fibers. Under the influence of impulses, elastic elastic tissue contracts. Shortening brings the ends of the muscle closer together, and with them the hip joint and ischium. When performing any movement, synergists are activated that prevent its implementation. The opposition of forces gives smoothness to movements. With intense exercise, muscle fatigue occurs.

Blood supply is provided by the inferior gluteal and obturator arteries. Blood vessels and nerves penetrate the fibers through the gate.

Functions of the twin muscles

The short gemellus muscles, together with eight other muscles (obturator internus, piriformis, quadratus, gluteus maximus and medius, adductor magnus, obturator externus and tensor fascia lata) are participants in the mechanism of external rotation of the hip. A group of synergists acts harmoniously, turning the hip joint outward. One of the functions m. gemellus superior – hip abduction during flexion, during extension the effect is insignificant. A typical example of an action is sticking out your leg when getting out of a car.

In the one-legged standing position, the muscle keeps the body from tilting in the opposite direction. Having a common tendon at the articulation of the trochanteric socket, the gemellus and obturator muscles contribute to the stable position of the femoral head.

Functional muscle tests

Functional testing is a method of studying muscles that simultaneously pursues several goals:

• assess the state of the motor stereotype;
• determine the strength of the twin and adjacent muscles;
• detect the site of peripheral nerve damage.

To assess muscle tone, the patient is placed on his back. The doctor performs passive movements, flexing and extending the limb at the hip joint. Be sure to compare the range of motion of the right and left legs. Muscle strength is assessed on a five-point system from 0 to 5. The doctor, holding the limb bent at the knee joint, asks the patient to make various movements with the lower leg. All tests are carried out slowly and carefully in order to obtain reliable results and not harm the patient.

Muscle pathologies

The painful state of the muscles is associated with dysfunction of tone. Loss of contractility, constant tension, and loss of muscle strength occur for various reasons. Among the main ones:

• injuries;
• sprains;
• defects in nervous regulation;
• inflammation caused by various diseases: infectious, autoimmune, viral.

Microtears in the twin muscles (up to 5% of fibers) manifest themselves as a feeling of discomfort and do not threaten human health. More serious injury results in pain during physical activity.

When the innervating plexuses are compressed, a nagging pain occurs, radiating to the buttocks and lower back. It subsides when lying down and resumes when walking. If the tendons are completely torn from the point of attachment to the bone (hip joint or ischium), surgical intervention is required.

Instrumental diagnostic methods (ultrasound, magnetic resonance imaging) and functional muscle tests help determine pathological changes in the gemellus musculus. Elastic tissues recover quickly, the main thing is to prevent the occurrence of scars at the rupture sites. Coarse inclusions prevent normal fiber stretching.

Gluteus maximus muscle(m. gluteus maximus) (Fig. 128, 132, 133, 134) extends the thigh, straightens the torso bent forward, stretches the lata fascia of the thigh, and fixes the pelvis and torso in a standing position. This is a large, flat, rhomboid muscle, the powerful development of which is explained by the upright posture of humans. It starts from the back of the outer (gluteal) surface of the ilium, from the lateral edge of the sacrum and coccyx. The lower bundles of the muscle are attached to the gluteal tuberosity of the femur, and the upper bundles are woven into the iliotibial tract. Between the gluteal tuberosity and the muscle there is the trochanteric bursa of the gluteus maximus muscle (bursa trochanterica m. giutei maximi).

Gluteus medius muscle(m. gluteus medius) (Fig. 128, 130, 133) abducts the thigh. In this case, the anterior bundles rotate the thigh inward, and the posterior bundles rotate the thigh outward. When the hip is in a fixed position, the pelvis moves to the side. Also takes part in straightening the body bent forward. This is a thick muscle located under the gluteus maximus muscle and consisting of superficial and deep layers of muscle bundles. The beams themselves are arranged fan-shaped. The origin of the muscle is on the outer surface of the iliac wing and on the fascia lata of the thigh, and the insertion point is on the greater trochanter of the femur. The trochanteric bursa of the gluteus medius muscle (bursa trochanterica m. giutei medii) is also located here. The gluteus minimus muscle (m. gluteus minimus) (Fig. 128, 131) abducts the thigh and takes part in straightening the body. It is covered by the gluteus medius muscle, its origin point is located on the outer surface of the iliac wing between the anterior and inferior gluteal lines. The muscle is attached to the anterior edge of the greater trochanter of the femur.

Rice. 128. Pelvic muscles rear view 1 - gluteus maximus muscle; 2 - gluteus minimus; 3 - piriformis muscle; 4 - superior gemellus muscle; 5 - gluteus medius muscle; 6 - inferior gemellus muscle; 7 - internal locking muscle; 8 - external locking muscle; 9 - quadratus femoris muscle
Rice. 129. 1 - psoas minor muscle; 2 - iliacus muscle; 3 - psoas major muscle; 4 - piriformis muscle; 5 - iliopsoas muscle; 6 - vascular lacuna; 7 - muscle that tightens the fascia lata of the thigh; 8 - pectinate muscle; 9 - long adductor muscle; 10 - sartorius muscle; 11 - thin muscle; 12 - the longest rectus femoris muscle; 13 - adductor magnus; 14 - iliotibial tract; 15 - vastus lateralis muscle; 16 - vastus medialis muscle; 17 - tendon of the longest rectus femoris muscle;
Rice. 130. Muscles of the pelvis and thigh, front view 1 - psoas major muscle; 2 - iliacus muscle; 3 - piriformis muscle; 4 - gluteus medius muscle; 5 - iliopectineal bursa; 6 - pectineus muscle; 7 - iliopsoas muscle; 8 - thin muscle; 9 - adductor magnus; 10 - long adductor muscle; 11 - vastus intermedius; 12 - vastus lateralis muscle; 13 - semimembranosus muscle; 14 - vastus medialis muscle; 15 - tendon of the longest rectus femoris muscle; 16 - tendon of the semitendinosus muscle; 17 - tendon of the gracilis muscle; 18 - sartorius tendon

Tensor fascia lata muscle(m. tensor fasciae latae) (Fig. 90, 129, 133), strains the lata fascia of the thigh and takes part in its flexion. This flat, elongated muscle is located on the anterolateral surface of the pelvis. It starts from the superior anterior iliac spine and attaches to the iliotibial tract.

Quadratus femoris(m. quadratus femoris) (Fig. 128, 136) rotates the thigh outward. It has the shape of a rectangle, partially covered by the gluteus maximus muscle. It starts from the lateral surface of the ischial tuberosity and attaches to the greater trochanter and intertrochanteric crest of the femur. The distal end of the muscle grows into the lata fascia of the thigh.

Superior gemellus(m. gemellus superis) (Fig. 128), like the square one, rotates the thigh outward. It is a muscle cord, the origin of which is located on the ischial spine, and the attachment point is in the trochanteric fossa of the femur.

Gemini inferior muscle(m. gemellus inferior) (Fig. 128) rotates the thigh outward. The origin of the muscle is the ischial tuberosity, and the attachment point is the trochanteric fossa of the femur.

External obturator muscle(m. obturatorius externum) (Fig. 109, 128, 131) together with the previous muscles rotates the thigh outward. The muscle is an irregular triangle, its origin point is located on the outer surface of the pubic and ischial bones in the area of ​​the locking membrane, and the attachment point is the trochanteric fossa of the femur.