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Зміст2. Duration of studies
4. Basic knowledges, abilities, skills, that necessary for the study themes (interdisciplinary integration)
5. Advices to the student.
Structure of the Thoracic Wall
The Landmarks and the Projections of the Thoracic Wall
The sternal angle (angle of Louis)
Apex Beat of the Heart
Lungs The apex of the lung
The anterior border of the right lung
The posterior border of the lung
The cervical pleura
The superior border
Thoracic Blood Vessels
The internal thoracic vessels
Posterior Chest Wall
The Thoracic Apertures
The Inferior Thoracic Aperture
Anatomic and physiologic changes in the thorax with aging
Ministry of Health of Ukraine
Bukovinian State Medical University
on methodical meeting of the Department of Anatomy, Topographical anatomy and Operative Surgery
“………”…………………….2008 р. (Protocol №……….)
The chief of department
for the 3d-year foreign students of English-spoken groups of the Medical Faculty
(speciality “General medicine”)
for independent work during the preparation to practical studies
the Theme of studies
“Topographical anatomy and operative surgery of the thoracic wall and pectoral gland”
Topographical Anatomy and Operative Surgery
of the Head, Neck, Thorax and Abdomen
“Topographical Anatomy and Operative Surgery of the Thorax”
Chernivtsi – 2008
1. Actuality of theme:
The topographical anatomy and operative surgery of the thorax are very importance, because without the knowledge about peculiarities and variants of structure, form, location and mutual location of their anatomical structures, their age-specific it is impossible to diagnose in a proper time and correctly and to prescribe a necessary treatment to the patient. Surgeons usually pay much attention to the topographo-anatomic basis of surgical operations on the thorax.
^ 2 working hours.
3. Objectives (concrete purposes):
To know the definition of regions of the thorax.
To know classification of surgical operations on the thorax.
To know the topographical anatomy and operative surgery of the thoracic wall and organs of the thoracic cavity.
5.1. Table of contents of the theme:
The thorax (or chest) is the region of the body between the neck and the abdomen. The framework of the walls of the thorax (thoracic cage) is formed posteriorly by the thoracic part of the vertebral column; anteriorly by the sternum and costal cartilages; laterally by the ribs and intercostal spaces; superiorly by the suprapleural membrane; and inferiorly by the diaphragm, which separates the thoracic cavity from the abdominal cavity. The thorax is an irregularly shaped cylinder with a narrow opening (superior thoracic aperture) superiorly and a relatively large opening (inferior thoracic aperture) inferiorly. The superior thoracic aperture is open, allowing continuity with the neck; the inferior thoracic aperture is closed by the diaphragm. The thoracic cage protects the lungs and heart and affords attachment for the muscles of the thorax, upper extremity, abdomen, and back.
The thoracic wall is covered on the outside by skin and by muscles attaching the shoulder girdle to the trunk. It is lined with parietal pleura.
As physicians you will be examining the chest to detect evidence of disease. Your examination will consist of inspection, palpation, percussion, and auscultation.
Inspection shows the configuration of the chest, the range of respiratory movement, and any inequalities on the two sides. The type and rate of respiration will also be noted.
Palpation will enable the physician to confirm the impressions gained by inspection, especially of the respiratory movements of the chest wall. Abnormal protuberances or recession of part of the chest wall will be noted. Abnormal pulsations will also be felt and tender areas detected.
Percussion is a sharp tapping of the chest wall with the fingers. This produces vibrations that extend through the tissues of the thorax. Air-containing organs such as the lungs produce a resonant note; conversely, a more solid viscus such as the heart produces a dull note. With practice, it is possible to distinguish the lungs from the heart or the liver by percussion.
Auscultation enables the physician to listen to the breath sounds as the air enters and leaves the respiratory passages. Should the alveoli or bronchi be diseased and filled with fluid, the nature of the breath sounds will be altered. The rate and rhythm of the heart can be confirmed by auscultation, and the various sounds produced by the heart and its valves during the different phases of the cardiac cycle can be heard. It may be possible to detect friction sounds produced by the rubbing together of diseased layers of pleura or pericardium.
To make these examinations, a physician must be familiar with the normal structure of the thorax and must have a mental image of the normal position of the lungs and heart in relation to identifiable surface landmarks. Furthermore, it is essential that a physician be able to relate any abnormal findings to easily identifiable bony landmarks so that he or she can accurately record and communicate them to colleagues.
Since the thoracic wall actively participates in the movements of respiration, many bony landmarks change their levels with each phase of respiration. In practice, to simplify matters, the levels given are those usually found at about midway between full inspiration and full expiration.
Anterior Chest Wall
The suprasternal notch is the superior margin of the manubrium sterni and is easily felt between the prominent medial ends of the clavicles in the midline. It lies opposite the lower border of the body of the second thoracic vertebra.
^ is the angle made between the manubrium and body of the sternum. It lies opposite the intervertebral disc between the 4th and 5th thoracic vertebrae.
The xiphisternal joint is the joint between the xiphoid process of the sternum and the body of the sternum. It lies opposite the body of the 9th thoracic vertebra.
The xiphoid process, lies in the depression where the converging costal margins form the infrasternal angle. The xiphoid projects over the left lobe of the liver into the epigastric region of the abdomen.
The subcostal, or infrasternal, angle is situated at the inferior end of the sternum, between the sternal attachments of the 7th costal cartilages.
The costal margin is the lower boundary of the thorax and is formed by the cartilages of the 7th, 8th, 9th, and 10th ribs and the ends of the eleventh and twelfth cartilages. The lowest part of the costal margin is formed by the 10th rib and lies at the level of the 3rd lumbar vertebra.
^ is subcutaneous throughout its entire length and can be easily palpated. It articulates at its lateral extremity with the acromion process of the scapula.
There are 12 pairs of ribs, all of which are attached posteriorly to the thoracic vertebrae. The upper 7 pairs are attached anteriorly to the sternum by their costal cartilages. The 8-10th pairs of ribs are attached anteriorly to each other and to the 7th rib by means of their costal cartilages and small synovial joints. The 11th and 12th pairs have no anterior attachment and are referred to as floating ribs.
A typical rib is a long, twisted, flat bone having a rounded, smooth superior border and a sharp, thin inferior border. The inferior border overhangs and forms the costal groove, which accommodates the intercostal vessels and nerve.
The first rib lies deep to the clavicle and cannot be palpated. The lateral surfaces of the remaining ribs can be felt by pressing the fingers upward into the axilla and drawing them downward over the lateral surface of the chest wall. The 12th rib can be used to identify a particular rib by counting from below. However, in some individuals, the 12th rib is very short and difficult to feel. For this reason an alternative method may be used to identify ribs by first palpating the sternal angle and the second costal cartilage.
In the male it usually lies in the fourth intercostal space about 4 inches (10 cm) from the midline. In the female its position is not constant.
The central tendon of the diaphragm lies directly behind the xiphisternal joint. In the midrespiratory position the summit of the right dome of the diaphragm arches upward as far as the upper border of the fifth rib in the midclavicular line, but the left dome only reaches as far as the lower border of the fifth rib.
The apex of the heart is formed by the lower portion of the left ventricle. The apex beat is caused by the apex of the heart being thrust forward against the thoracic wall as the heart contracts. The apex beat is normally found in the 5th left intercostal space 9 cm from the midline.
Should you have difficulty in finding the apex beat, have the patient lean forward in the sitting position. In the female with pendulous breasts, the examining fingers should gently raise the left breast from below as the intercostal spaces are palpated.
The anterior fold is formed by the lower border of the pectoralis major muscle. This can be made to stand out by asking the patient to press a hand hard against the hip. The posterior fold is formed by the tendon
The trachea extends from the lower border of the cricoid cartilage (opposite the body of the sixth cervical vertebra) in the neck to the level of the sternal angle in the thorax. It commences in the midline and ends just to the right of the midline by dividing into the right and left principal bronchi. At the root of the neck it may be palpated in the midline in the suprasternal notch.
The apex of the lung projects into the neck. It can be mapped out on the anterior surface of the body by drawing a curved line, convex upward, from the sternoclavicular joint to a point 2.5 cm above the junction of the medial and intermediate thirds of the clavicle.
^ begins behind the sternoclavicular joint and runs downward almost reaching the midline behind the sternal angle. It then continues downward until it reaches the xiphisternal joint.
The anterior border of the left lung has a similar course, but at the level of the fourth costal cartilage it deviates laterally and extends for a variable distance beyond the lateral margin of the sternum to form the cardiac notch. This notch is produced by the heart displacing the lung to the left. The anterior border then turns sharply downward to the level of the xiphisternal joint.
The lower border of the lung in midinspiration follows a curving line, which crosses the sixth rib in the midclavicular line and the eighth rib in the midaxillary line, and reaches the tenth rib adjacent to the vertebral column posteriorly. It is important to understand that the level of the inferior border of the lung changes during inspiration and expiration.
^ extends downward from the spinous process of the seventh cervical vertebra to the level of the tenth thoracic vertebra and lies about 4 cm from the midline.
The oblique fissure of the lung can be indicated on the surface by a line drawn from the root of the spine of the scapula obliquely downward, laterally and anteriorly, following the course of the sixth rib to the sixth costochondral junction. In the left lung the upper lobe lies above and anterior to this line; the lower lobe lies below and posterior to it.
In the right lung is an additional fissure, the horizontal fissure, which may be represented by a line drawn horizontally along the fourth costal cartilage to meet the oblique fissure in the midaxillary line. Above the horizontal fissure lies the upper lobe and below it lies the middle lobe; below and posterior to the oblique fissure lies the lower lobe.
The boundaries of the pleural sac can be marked out as lines on the surface of the body. The lines, which indicate the limits of the parietal pleura where it lies close to the body surface, are referred to as the lines of pleural reflection.
^ bulges upward into the neck and has a surface marking identical to that of the apex of the lung. A curved line may be drawn, convex upward, from the sternoclavicular joint to a point 2.5 cm above the junction of the medial and intermediate thirds of the clavicle.
The anterior border of the right pleura runs down behind the sternoclavicular joint, almost reaching the midline behind the sternal angle. It then continues downward until it reaches the xiphisternal joint. The anterior border of the left pleura has a similar course, but at the level of the fourth costal cartilage it deviates laterally and extends to the lateral margin of the sternum to form the cardiac notch. Note that the pleural cardiac notch is not as large as the cardiac notch of the lung. It then turns sharply downward to the xiphisternal joint.
The lower border of the pleura on both sides follows a curved line, which crosses the 8th rib in the midclavicular line and the 10th rib in the midaxillary line, and reaches the 12th rib adjacent to the vertebral column, that is, at the lateral border of the erector spinae muscle. Note that the lower margins of the lungs cross the 6th, 8th, and 10th ribs at the midclavicular lines, the midaxillary lines, and the sides of the vertebral column, respectively, and the lower margins of the pleura cross, at the same points, respectively, the 8th, 10th, and 12th ribs. The distance between the two borders corresponds to the costodiaphragmatic recess.
For practical purposes the heart may be considered to have both an apex and four borders. The apex, formed by the left ventricle, corresponds to the apex beat and is found in the fifth left intercostal space 9 cm from the midline.
^ formed by the roots of the great blood vessels, extends from a point on the 2nd left costal cartilage (remember sternal angle) 1.5 cm from the edge of the sternum to a point on the third right costal cartilage 1.5 cm from the edge of the sternum.
The right border, formed by the right atrium, extends from a point on the third right costal cartilage 1.5 cm from the edge of the sternum downward to a point on the 6th right costal cartilage 1.5 cm from the edge of the sternum.
The left border, formed by the left ventricle, extends from a point on the 2nd left costal cartilage 1.5 cm from the edge of the sternum to the apex beat of the heart.
The inferior border, formed by the right ventricle and the apical part of the left ventricle, extends from the 6th right costal cartilage 1.5 cm from the sternum to the apex beat.
The arch of the aorta and the roots of the brachiocephalic and left common carotid arteries lie behind the manubrium sterni.
The superior vena cava and the terminal parts of the right and left brachiocephalic veins also lie behind the manubrium sterni.
^ run vertically downward, posterior to the costal cartilages, 1.5 cm lateral to the edge of the sternum, as far as the 6th intercostal space.
The intercostal vessels and nerve ("vein, artery, nerve" – VAN - is the order from above downward) are situated immediately below their corresponding ribs.
The spinous processes of the thoracic vertebrae can be palpated in the midline posteriorly. The first spinous process to be felt is that of the 7th cervical vertebrae (vertebra prominens). Below this level are the overlapping spines of the thoracic vertebrae. The spines of C1-6 vertebrae are covered by a large ligament, the ligamentum nuchae. It should be noted that the tip of a spinous process of a thoracic vertebra lies posterior to the body of the next vertebra below.
The scapula (shoulder blade) is flat and triangular in shape and is located on the upper part of the posterior surface of the thorax. The superior angle lies opposite the spine of the 2nd thoracic vertebra. The spine of the scapula is subcutaneous, and the root of the spine lies on a level with the spine of the 3rd thoracic vertebra. The inferior angle lies on a level with the spine of the 7th thoracic vertebra.
The bony thorax has two apertures or openings.
The superior thoracic aperture is often referred to as the thoracic inlet, and the inferior thoracic aperture is sometimes called the thoracic outlet.
The Superior Thoracic Aperture
The head, neck, and limbs communicate with the thoracic cavity through the thoracic inlet or superior thoracic aperture. Through this relatively small, kidney-shaped opening (about 5 cm anteroposteriorly and 11 cm transversely) pass structures entering and leaving the thorax, such as the trachea (windpipe), esophagus (gullet), and the great arteries and veins that supply and drain the head, neck, and upper limbs.
This aperture is limited by the body of the first thoracic vertebra posteriorly, the first pair of ribs and their costal cartilages anterolaterally, and the superior end of the manubrium of the sternum anteriorly. As the margin of the aperture slopes inferoanteriorly, the apex of each lung and its covering of pleura (pleural cupula) project superiorly through the lateral parts of the thoracic inlet.
At the thoracic outlet or inferior thoracic aperture, the thoracic cavity is separated from the abdominal cavity by the musculotendinous thoracic diaphragm. Most structures that pass from the thorax to the abdomen, or vice versa, go through openings in the diaphragm (e.g., the inferior vena cava, aorta, and esophagus). The thoracic outlet is uneven and is much larger than the superior thoracic aperture.
The inferior thoracic aperture, which slopes inferoposteriorly, is limited by the 12th thoracic vertebra posteriorly, the 12th pair of ribs and costal margins anterolaterally, and the xiphisternal joint anteriorly.
On its way to the upper limb, the subclavian artery crosses the first rib, producing a distinct groove. This artery may be compressed where it passes over this rib, producing vascular symptoms, e.g., pallor, coldness, and cyanosis (blue color) of the hands. Less frequently, nerve pressure symptoms (numbness and tingling) in the digits result from pressure on the inferior trunk of the brachial plexus. These conditions have been described under several different terms (e.g., the thoracic inlet syndrome), depending on what the author thought was the cause of the symptoms.
Usually the condition is called the neurovascular compression syndrome. The designation thoracic inlet syndrome has also been used to describe the signs and symptoms resulting from multiple enlarged lymph nodes that constrict the superior thoracic aperture or thoracic inlet. These nodes usually enlarge as the result of infiltration of them by malignant cells from a lymphosarcoma, a lymphatic tumor. As a result, blood does not drain normally from the head, neck, and upper limbs and they become congested with blood and appear swollen.
Certain anatomic and physiologic changes take place in the thorax with advancing years:
• The rib cage becomes more rigid and loses its elasticity as the result of calcification and even ossification of the costal cartilages; this also alters their usual radiographic appearance.
• The stooped posture (kyphosis), so often seen in the old because of degeneration of the intervertebral discs, decreases the chest capacity.
• ^ of the thoracic and abdominal muscles can result in poor respiratory movements.
• Degeneration of the elastic tissue in the lungs and bronchi results in impairment of the movement of expiration.
These changes, when severe, diminish the efficiency of respiratory movements and impair the ability of the individual to withstand respiratory disease.