Sternum (sternum) is an unpaired long flat spongy bone *, consisting of 3 parts: the handle, the body and the xiphoid process.

* (The cancellous bone is rich in the circulatory system and contains red bone marrow in people of any age. Therefore, it is possible: intrasternal blood transfusion, taking red bone marrow for research, transplantation of red bone marrow.)

Sternum and ribs... A - sternum (sternum): 1 - sternum handle (manubrium sterni); 2 - the body of the sternum (corpus sterni); 3 - xiphoid process (processus xiphoideus); 4 - rib cuts (incisurae costales); 5 - the angle of the sternum (angulus sterni); 6 - jugular notch (incisure jugularis); 7 - clavicular notch (incisure clavicularis). B - VIII rib (inside view): 1 - articular surface of the rib head (facies articularis capitis costae); 2 - neck of the rib (collum costae); 3 - rib angle (angulus costae); 4 - rib body (corpus costae); 5 - rib groove (sulcus costae). B - I rib (top view): 1 - neck of the rib (collum costae); 2 - tubercle of the rib (tuberculum costae); 3 - groove of the subclavian artery (sulcus a. Subclaviae); 4 - groove of the subclavian vein (sulcus v. Subclaviae); 5 - tubercle of the anterior scalene muscle (tuberculum m. Scaleni anterioris)

Lever makes up the upper part of the sternum, on its upper edge there are 3 notches: unpaired jugular and paired clavicular, which serve to articulate with the sternal ends of the clavicles. On the side surface of the handle, two more notches are visible - for the I and II ribs. The handle, connecting with the body, forms an anteriorly directed angle of the sternum. In this place, the II rib is attached to the sternum.

Sternum body long, flat, expanding downward. On the lateral edges it has cutouts for attaching the cartilaginous parts of the II-VII pairs of ribs.

Xiphoid process - this is the most variable in shape of the sternum. As a rule, it has the shape of a triangle, but it can be bifurcated downwards or have a hole in the center. By the age of 30 (sometimes later), parts of the sternum grow together into one bone.

Ribs (costae) are paired bones of the chest. Each rib has bone and cartilaginous parts. The ribs are divided into groups:

1. true from I to VII - attached to the sternum;
2. false from VIII to X - have a common fastening with a costal arch;
3. hesitant XI and XII - have free ends and are not attached.

The bony part of the rib (os costale) is a long spiral-shaped curved bone in which the head, neck and body are distinguished. Rib head located at the back end of it. It bears an articular surface for articulation with the costal fossa of two adjacent vertebrae. The head goes into rib neck... Between the neck and the body, a rib tubercle is visible with an articular surface for articulation with the transverse process of the vertebra. (Since the XI and XII ribs do not articulate with the transverse processes of the corresponding vertebrae, there is no articular surface on their tubercles.) Rib body long, flat, curved. It distinguishes between the upper and lower edges, as well as the outer and inner surfaces. On the inner surface of the rib, along its lower edge, there is a groove of the rib, in which the intercostal vessels and nerves are located. The body length increases to the VII-VIII ribs, and then gradually decreases. At the top 10 ribs, the body immediately behind the tubercle forms a bend - the rib angle.

The first (I) rib, unlike the others, has an upper and a lower surface, as well as an outer and inner edge. On the upper surface, at the anterior end of the 1st rib, a tubercle of the anterior scalene muscle is visible. In front of the tubercle is the groove of the subclavian vein, and behind is the groove of the subclavian artery.

Rib cage in general (compages thoracis, thorax) is formed by twelve thoracic vertebrae, ribs and sternum. Its upper aperture is limited behind by the I thoracic vertebra, from the sides by the I rib and in front by the handle of the sternum. The inferior aperture of the chest is much wider. Its border is made up of the XII thoracic vertebra, XII and XI ribs, the costal arch and the xiphoid process. The costal arches and the xiphoid process form the sub-sternal angle. The intercostal spaces are clearly visible, and inside the chest, on the sides of the spine, there are pulmonary grooves. The back and side walls of the chest are much longer than the front. In a living person, the bony walls of the chest are supplemented with muscles: the lower aperture is closed by the diaphragm, and the intercostal spaces are closed by the muscles of the same name. Inside the chest, in the chest cavity, are the heart, lungs, thymus gland, large vessels and nerves.

The shape of the chest has sex and age differences. In men, it expands downward, conical, and is large. The ribcage of women is smaller, ovoid: narrow at the top, wide in the middle and tapering again downward. In newborns, the ribcage is somewhat compressed from the sides and extended anteriorly.

Rib cage... 1 - upper chest aperture (apertura thoracis superior); 2 - sternocostal joints (articulationes sternocostales); 3 - intercostal space (spatium intercostale); 4 - sub-sternal angle (angulus infrasternalis); 5 - costal arch (arcus costalis); 6 - lower chest aperture (apertura thoracis inferior)

In shape, the ribcage resembles a vegetable with a narrow upper end and a wider lower end, with both ends cut obliquely. Rib cage ( compagesthoracis) has 2 apertures: the upper ( aperturathoracissuperior) lower ( apertura thoracis inferior) tightened by the muscular septum of the diaphragm. The ribs limit the lower aperture, form the costal doga ( arcuscostales). The chest is made up of: the thoracic spine, ribs (12 pairs), sternum. Distinguish between front and rear side walls. The anterior wall is shorter than the other walls, formed by the sternum and cartilage of the ribs. The posterior wall is longer than the anterior one formed by the thoracic vertebrae and sections of the ribs from the heads to the corners. There are pulmonary grooves ( sulcipulmonales), which fit the back of the light. The space between the ribs is intercostal ( spatia intercostalea) The side walls are longer than the front and rear, formed by the bodies of the ribs and are more or less convex. The shape of the pectoralis is different for different people (flat, cylindrical, conical). The ribcage in men is longer and wider and more tapered than in women. The shape of the chest also depends on age.

Connections of the clavicle with the scapula and sternum.

Sternoclavicular joint (art. Sternoclavicularis) is formed by the clavicular notch of the sternum and the sternal end of the clavicle. The joint is simple. The articular surfaces are covered with connective tissue cartilage, often saddle-shaped. Their discrepancy is leveled out by the articular disc. The joint capsule is firmly attached to the edges of the articular surfaces of the bone. Through the disc, the joint cavity is divided into two non-communicating parts. The ligamentous apparatus of the sternoclavicular joint includes the ligaments: 1) Anterior, posterior sternoclavicular ( ligg. Sternoklavikulareanteriusetposterius) strengthen the joint capsule from the front, from above, from behind. 2) costoclavicular ( lig. Costoclaviulare) goes from the upper edge of the first rib of the clavicle. 3) Interclavicular ligament ( lig. Interaclaviculare) stretched between the sternal ends of the clavicle.

Acromioclavicular joint(art. Acromioclavicularis) is formed by the articular surface of the shoulder end of the clavicle and the articular surface of the scapula acromion. The joint is simple art. Simplecs articular surfaces are flat. The joint cavity is divided into two parts by the articular disc. Multi-axle but with severely limited range of motion artt. Planae. Strengthening ligaments: 1) acromioclavicular ( lig. Aromioclavicularis) between the acromial end of the clavicle and the acromion of the scapula. 2) coracoclavicular ( lig. Coracoclaviculare) connects the acromial end of the clavicle and the acromial end of the scapula. 3) the conical ligament (lig. Conoideum) is stretched between the cone-shaped tubercle of the acromial end of the clavicle and the coracoid process of the scapula. Ligaments of the scapula: lig. Carocoacromiale - stretches from the front edge of the acromion to procуssus carocoideus 2) lig. Transversum scapule superius extends over the notch of the scapula. 3) lig. Tranversum scapule inferius runs from the base of the acromion 2/3 of the scapula neck to the posterior edge of the cavity.

Shoulder joint: formation, ligaments, movements. (art. Humeri)

Formed by the articular cavity of the scapula ( cavitas glenoidalis sscapulae) and the head of the humerus ( caput humeri) articular surfaces with geolinic cartilage and do not correspond to each other: the congruence of the articular surfaces increases due to the articular lip ( labium glenoidale). The articular capsule is fixed on the scapula along the edge of the articular cartilage of the articular cavity and along the outer edge of the articular lip; on the humerus, it is attached along the anatomical neck. On the inner surface of the articular capsule, the tris-brachial ligaments ( ligg. Glenohumerale). They are attached on one side with a rope of the neck of the humerus on the other to the articular lip of the scapula. In addition, the shoulder joint has a powerful coracohumeral ligament ( lig. Coracohumerale) it goes from the outer edge of the coracoid process to the large tubercle of the humerus. Coracoacromial ligament ( lig. Coracoacromiale) goes over the shoulder joint together with the acromion and the coracoid process of the scapula forms. The shoulder joint is triaxial in shape, spherical ( art. Spheroidea) (circumduction) movement along all soybeans is frontal, Sagittal, Vertical, there are also circular movements. around the frontal axis of flexion-flexion, around the sagittal axis - abduction-ghost, around the vertical rotation.

Elbow joint: formations, ligaments, movements. (art. Cubiti)

In the elbow joint 3 bones are articulated: humerus, ulna, radius. The articulating bones form 3 joints, enclosed in one capsule. The elbow joint is formed by the articular surface of the distal epiphysis of the humerus - its block and the head of the condyle, articular surfaces on the ulna - the block and radial notches of the ulna, as well as the head and articular circumference of the radial bone. Complicated joint ( art. Composita). Flexion and extension, pronation and supination are possible in the elbow joint. The articular surfaces are covered with geolinic cartilage. In the cavity of the elbow joint, 3 joints are distinguished: 1) Shoulder-elbow ( art. Humeroulnaris) is a blocky joint with a helical structure of the articular surfaces. The articular surface from the side of the shoulder is a block ( trohlea); the recess located on it is not perpendicular to the block axis, but at a certain angle to it - a screw stroke is obtained. Articulates with the block incisura trohlearis the ulna. Single-axle ( ginglymus) 2) brachioradial ( art. Humerоradialis) Formed by the head of the condyle of the humerus and the glenoid fossa on the head of the radius, it belongs to the spherical ( art. Spheroideae), the movement is performed around 2 axes: frontal and vertical. 3) Proximal ray-ulnar ( art. Radioulnarisproximalis) lies between the radial apex of the ulna and the articular circumference of the radial head. The joint is cylindrical.

Ribs and sternum. Chest as a whole

Biology and genetics

At the vertebral end of the rib there are: a head with a ridge at the IIX ribs and the upper lower articular surfaces covered with hyaline cartilage at the I XI and XII ribs the ridge is absent; the neck passing by an angle into the body; at the transition of the tubercle on 10 upper ribs with two elevations: the medial-lower one has a glenoid fossa for articulation with the transverse process of the vertebra, a ligament is attached to another elevation; the last two edges of the tubercle do not have a tubercle at the first edge coincides with the apex of the angle. The rib body is curved at the vertebral end ...

Ribs and sternum. Chest as a whole.

The rib has a vertebral and sternal ends, the vertebral consists of the posterior and lateral parts - bone, the sternum - of a small front part - cartilaginous and bone.

At the vertebral end of the rib there are:

1. the head with a crest at II-X ribs and the upper, lower articular surfaces covered with hyaline cartilage, atI, XI and XII ridge ribs are missing;
2. the neck, passing by an angle into the body; at the transition - a tubercle on 10 upper ribs with two elevations: the medial-lower one has a glenoid fossa for articulation with the transverse process of the vertebra, a ligament is attached to another elevation; the last two ribs have no tubercle, at the first rib the tubercle coincides with the apex of the angle.

The rib body, curved at the vertebral end with a gentle angle, has a groove on the lower edge on the inner surface for intercostal vessels and nerves.

The edges of the ribs (II-XII): the upper is rounded, the lower is sharp, serve to attach the intercostal muscles; at the first rib - the lateral and inner edge and the upper surface with the scalene tubercle and the groove of the subclavian vessels.

Surfaces of the ribs (II-XII): front (inner) - smooth adjacent to the pleura, back (outer) - rough for attaching the muscles of the back, at the first rib the upper and lower surfaces.

Ribs are subdivided into:

1. true (upper seven ribs) - they form joints with the sternum, except for the first, which is associated with synchondrosis and false (YIII, IX, X) - they grow together with cartilages and form a costal arch, floating (XI, XII) - short, freely lying among the abdominal muscles;
2. typical (II-X);
3. atypical (I, XI, XII) due to differences in structure: on the first rib along the upper surface (outer edge) there is a scalene tubercle, grooves of the subclavian artery and vein; its edges are lateral and medial (lateral and internal), the surfaces are upper and lower; XI, XII ribs are short with a very small cartilaginous part, do not connect with the sternum and other ribs.

Sternum

Flat bone, consisting of:

1. handle, body, xiphoid process;
2. front and back surfaces;
3. right and left lateral edges, bearing rib cuts on the body.

Along the upper edge of the sternum handle there are an unpaired jugular notch and paired clavicular notches, along the lateral edge of the handle there is a depression for synchondrosis of the 1st rib and a half-well for the 2nd rib.The lower edge of the handle fuses with the body at an obtuse angle, open posteriorly towards the spine.

The ribs and sternum develop from the ventral arches of the somites, first in the form of fibrous thoracic stripes, which quickly become cartilaginous, at the 8th week, primary ossification nuclei appear in the costal corners, and secondary nuclei appear in the head and tubercle at 15-20 years, complete ossification of the ribs at 18-25 years old.

The sternum is formed when the chest stripes grow together along the anterior midline. The primary nuclei of bone tissue appear in the handle at 4-6 months, in the body - at 7-8 months of the fetal period. Secondary nuclei appear at 1 year of life in the lower body, in the xiphoid process at 6–20 years. Complete ossification of the body occurs at the age of 15-20, the entire sternum - by the age of 30. Between the handle and the body, ossification may not occur throughout the life of the individual.

Variants and developmental anomalies

1. The appearance of additional ribs: cervical, lumbar.
2. Rare absence of XI, XII ribs.
3. Fusion or splitting of the front ends of the ribs.
4. The presence of holes and cracks in the sternum.
5. Splitting of the sternum with no fusion of the right and left rudiments.

The ribs are connected with the vertebrae by the costal-vertebral joints:

1. each rib - by the joint of the head of the rib, which is reinforced with ligaments - from the second to the tenth by the intra-articular ligament of the head, in all joints (I-XII) - outside by the radiant ligament;
2. top 10 ribs - costal-transverse joints: right and left, strengthened by the same ligaments;
3. all joints are combined, simple, ellipsoidal.

The ribs are connected to the sternum:

1. sternocostal joints (II - YII ), strengthened by the sternocostal radiant ligaments, which form the front of the sternum membrane;
2. synchondrosis - between the first rib and the sternum, between the YIII-X ribs;
3. rare interchondral joints YIII-X ribs.

The ribs are interconnected by fibrous membranes:

1. external intercostal membrane - anterior, sternal ends;
2. the inner intercostal membrane - the posterior, vertebral ends.

The rib cage is formed by 12 thoracic vertebrae, 12 ribs, the sternum and various connections between them: intervertebral symphysis, joints and syndesmosis, sternocostal joints and synchondrosis, costal-vertebral joints and intercostal membranes.

In the chest there are: anterior, two lateral - right and left, posterior walls, upper and lower apertures, intercostal spaces, pulmonary grooves (in the area of \u200b\u200brib corners), costal arch (fusion of cartilage of false ribs), sub-sternal angle between costal arches with apex at the xiphoid process.

For the projection of the boundaries of the heart, lungs, pleura, a number of conditional lines are drawn through the chest: the anterior median (through the middle of the sternum), sternal (along the right and left edges of the sternum), midclavicular, axillary (anterior, middle, posterior), scapular, paravertebral, vertebral (along the edges of the transverse processes), the posterior median (along the spinous processes).

Using the listed lines of the vertical (longitudinal) direction and the ribs and intercostal spaces located transversely to them, the boundaries of the internal organs are established.

When determining the shape of the chest, the ratio of its dimensions is used: anteroposterior and transverse, which establishes an individual type of structure.

For the brachymorphic body type, the characteristic is the conical shape of the chest with a wide lower part, an obtuse sub-sternal angle, wide intercostal spaces, slightly inclined downward.

In the dolichomorphic type, the chest is flat with a short anteroposterior dimension and a long transverse one, the sub-sternal angle is acute, the intercostal spaces are narrow and strongly inclined downward.

With the mesomorphic type, the chest is cylindrical.

Women have a shorter and more rounded rib cage, while men have a longer and more prominent chest. In newborns, the anteroposterior dimension prevails over the transverse one.

Some diseases and professional activities are reflected in the shape of the chest.

When inhaling, the front ends of the ribs and the sternum rise by 1 cm, upward and 5 cm anteriorly, the chest circumference increases by 10 cm due to the muscles of the diaphragm, external intercostal, rib lifters as part of the extensor of the back, posterior superior dentate and scalene muscles. In the act of exhalation, the transverse muscle of the chest, internal intercostal, dentate posterior lower, rectus, oblique and transverse abdominal muscles are involved.

The blood supply, innervation of the intercostal muscles, rib lifters, serratus muscles, transverse chest muscle and abdominal muscles is carried out by intercostal vessels and nerves. The diaphragm is supplied with the upper and lower phrenic vessels, the nerve of the same name. The intercostal, lumbar and epigastric vessels and nerves are involved in the supply of the abdominal muscles, as well as: the hypochondrium, ilio-hypogastric and ilio-inguinal nerves from the lumbar plexus.

Development of the skull in ontogenesis. Individual, age and sex characteristics of the skull.

Short version

The shape of the chest has sex and age differences. In men, it expands downward, conical, and is large. The ribcage of women is smaller, ovoid: narrow at the top, wide in the middle and again tapering downward. In newborns, the ribcage is somewhat compressed from the sides and extended anteriorly.

Original

The shape of the chest has sex and age differences. In men, it expands downward, conical, and is large. The ribcage of women is smaller, ovoid: narrow at the top, wide in the middle and tapering again downward. In newborns, the rib cage is somewhat compressed from the sides and extended anteriorly.

Anatomy of the chest: Chest as a whole. In its shape, the ribcage resembles an ovoid with an upper narrow end and a wider lower end, both ends being cut obliquely. In addition, the chest ovoid is somewhat compressed from front to back. The rib cage has two openings or apertures: the upper and the lower, tightened by a muscular septum - the diaphragm. The ribs bounding the lower aperture form a costal arch. The anterior edge of the lower aperture has a notch in the shape of an angle, a sub-sternal angle; at its apex lies the xiphoid process. The vertebral column protrudes into the chest cavity along the midline, and on the sides of it, between it and the ribs, wide pulmonary grooves are obtained, in which the posterior edges of the lungs are placed. The spaces between the ribs are called the intercostal spaces. In mammals, in which, due to their horizontal position, the thoracic insides exert pressure on the lower wall, the thorax is long and narrow, and the ventro-dorsal dimension exceeds the transverse one, as a result of which the thorax has a sort of laterally compressed shape with a protruding ventral wall in the form of a keel (keel-shaped). In monkeys, due to the division of the limbs into arms and legs and the beginning transition to upright posture, the chest becomes wider and shorter, however, the ventro-dorsal dimension still prevails over the transverse one (monkey shape). Finally, in a person, in connection with a complete transition to upright posture, the hand is freed from the function of movement and becomes a grasping organ of labor, as a result of which the chest experiences the pull of the muscles of the upper limb attached to it; the insides do not press on the ventral wall, which has now become anterior, but on the lower one formed by the diaphragm, as a result of which the line of gravity with the vertical position of the body is transferred closer to the spinal column. All this leads to the fact that the rib cage becomes flat and wide, so that the transverse dimension exceeds the anteroposterior one. Reflecting this process of phylogenesis, and in ontogeny, the chest has different forms. As the child begins to get up, walk and use his limbs, and also as the entire apparatus of movement and viscera grows and develops, the chest gradually acquires a characteristic human shape with a predominant transverse dimension. The shape and size of the chest are also subject to significant individual variations due to the degree of development of the muscles and lungs, which in turn is associated with the lifestyle and profession of the person. Since it contains such vital organs as the heart and lungs, these variations are of great importance for assessing the physical development of an individual and diagnosing internal diseases. Usually, three forms of the chest are distinguished: flat, cylindrical and conical. In people with well-developed muscles and lungs, the chest becomes wide, but short and takes on a conical shape, that is, its lower part is wider than the upper one, the ribs are slightly inclined, large. Such a chest is, as it were, in a state of inhalation, which is why it is called inspiratory. On the contrary, in people with poorly developed muscles and lungs, the ribcage becomes narrow and long, acquiring a flat shape, in which the ribcage is strongly flattened in the anteroposterior diameter, so that its anterior wall stands almost vertical, the ribs are strongly inclined, sharp. The chest is, as it were, in a state of exhalation, which is why it is called expiratory. The cylindrical shape takes an intermediate position between the two described. In women, the rib cage is shorter and narrower in the lower part than in men, and more rounded. Social factors on the shape of the chest are reflected in the fact that, for example, in some capitalist and developing countries, children of the exploited strata of the population living in dark houses, with a lack of nutrition and solar radiation, develop rickets ("English disease"), in which the chest takes the form of a "chicken breast": the anteroposterior size prevails, and the sternum abnormally protrudes forward, like in chickens. In pre-revolutionary Russia, shoemakers, who all their life sat on a low stool in a bent position and used their chest as a support for the heel when driving nails into the sole, a depression appeared on the front wall of the chest, and it became sunken (funnel-shaped chest of shoemakers). In children with long and flat chests, due to poor muscular development due to improper sitting on the desk, the chest is as if in a collapsed state, which affects the activity of the heart and lungs. To avoid diseases of children, physical education is needed. Chest movements. Respiratory movements consist of alternately raising and lowering the ribs, along with which the sternum moves. During inhalation, the rear ends of the ribs rotate around the axis mentioned in the description of the ribs connections, and their front ends are raised so that the chest expands in the anteroposterior dimension. Due to the oblique direction of the axis of rotation, the ribs are simultaneously moved to the sides, as a result of which the transverse size of the chest also increases. When the ribs are lifted, the angular bends of the cartilage straighten, there are movements in the joints between them and the sternum, and then the cartilage itself is stretched and twisted. At the end of the inhalation caused by the muscular act, the ribs drop, and then exhalation begins.

LITERATURE

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2. Vaynek, Yu. Sports anatomy \u003d Sportanatomie: textbook. manual for students of higher. study. institutions / Y. Vaynek; per. with him. V.A. Kuzemina; scientific. ed. A.V. Chogovadze. - M .: Academy, 2008 .-- 304s.

3. Zhuikov, A.E. Osteology: textbook. manual / A.E. Zhuikov. Ukhta: USTU, 2012 .-- 159p.

4. Ivanitsky, M.F. Human anatomy (with the basics of dynamic and sports morphology) [Text]: textbook. for institutes of physical culture / M.F. Ivanitsky .; ed. B.A. Nikityuk, A.A. Gladysheva, F.V. Sudzilovsky. - M .: Terra-sport, 2003 .-- 624s.