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s of the lungs are situated opposite the fourth, fifth, and sixth thoracic vay between them and the vertebral margins of the scapulæ. Crus of diaphragm
Crns of diaphragm
eral lum bo-costal
95.-DISSECTION FROM BEHIND TO SHOW THE RELATION OF THE TWO PLEURAL SACS TO TAE KIDNEYS. tlines of superior portions of the two kidneys are indicated by dotted lines. (From Cunningham.)
e lower end of the trachea, the bronchi, the vagi, and the left recurrent nerve, are all or less surrounded by lymph glands, which, when enlarged, may exert injurious pressure them.
Viewed from the front, the outline of the precordial area, like that of the perilial sac, is roughly triangular, the base of the triangle being below and the apex ve. The boundaries are delineated upon the surface as follows :The right side of the triangle, formed by the right atrium, is indicated by wing a line slightly convex laterally from the superior end of the third to the th costal cartilage, a finger's breadth from the edge of the sternum; the curve tains its maximum opposite the fourth intercostal space, where it reaches one nd a half inch from the median plane.
The base of the triangle, formed by the margo acutus of the right ventricle and a very slight extent by the apical portion of the left ventricle, is almost horizontal, and corresponds to a line drawn from the inferior extremity of the right ide of the triangle to the apex of the left ventricle, which lies behind the fifth left intercostal space, three and a half inches from the median plane, and half an inch medial to the mid-clavicular line. The base line crosses the xiphoid process at its junction with the body of the sternum.
The left side of the triangle, formed by the margo obtusus of the left ventricle, is indicated by a slightly curved line extending from the apex of the heart upwards to the inferior edge of the second interspace, a finger's breadth from the sternum, the convexity of the curve being directed laterally and slightly upwards.
The truncated apex of the triangle, which lies behind the sternum at the level of the second intercostal space, corresponds to the highest part of the heart, namely, where the auricles of the atria embrace the aorta and pulmonary artery.
The situation of the anterior part of the coronary sulcus is mapped out by a line drawn from the median plane, opposite the inferior border of the third left costal cartilage, downwards and laterally to the sixth right chondro - sternal junction; the line should be slightly convex upwards and to the right. The right auricle lies at, or a little to the right of, the median plane, at the level of the second
se trachea. the supra-s
Atrium the roo
space and the superior border of the third costal cartilage. The lies behind the second left intercostal space, close to the edge of the
iphragmatic or inferior surface of the heart rests upon the diaphragmatic irt of the pericardium. The base, or true posterior surface, of the heart is inly by the left atrium, which is moulded posteriorly upon the esophagus, , the bronchi, and the bronchial glands, the pericardium intervening. trium extends behind the right atrium for a considerable distance to the he median plane. radiographic examination in cases of general visceroptosis, the diaphragm, ould rise and fall opposite the xiphisternal junction, will be seen to be an nore lower down, while the heart is seen to hang more vertically than cardioptosis). etermining the position of the cardiac orifices and their valves it is to be ered that they are all situated below and to the left of the anterior part oronary sulcus, and that they lie in the following order from above down-viz., pulmonary, aortic, mitral, and tricuspid. When delineated on the they will be seen to lie within an ellipse whose long axis extends from the c border of the third left to the sixth right chondro-sternal junction.
pulmonary orifice, directed upwards and slightly backwards and to the left, posite the superior border of the third left chondro-sternal junction ; the aortic directed upwards, backwards, and to the right, lies further from the surface, the left half of the sternum, opposite the inferior border of the third costal ge; the mitral orifice lies at an inferior level, behind the left half of the sternum, te the fourth rib; the orifice of the opening is directed downwards, forwards, o the left. The tricuspid orifice, situated nearer the anterior wall of the chest the mitral, lies very obliquely behind the right half of the sternum at the of the fourth and fifth cartilages and intervening space. though the first and second sounds of the heart are heard all over the cardiac area, the s produced by the individual valves are heard most distinctly, not directly over their anaal situation, but over the area where the cavity in which the valve lies approaches nearest e surface. Hence the mitral sound is best heard over the apex (mitral area), the tricuspid the inferior part of the body of the sternum (tricuspid area), the aortic over the second right 1 cartilage (aortic area), and the pulmonary over the second left intercostal space (pulmonary n tapping the pericardium (paracentesis pericardii) the pleura will be avoided by making puncture through the fifth or sixth left intercostal space as close as possible to the edge of the
When, however, the pericardial sac is distended with fluid, the pleura is pushed rally, and will therefore escape injury if the puncture is made at a safe distance lateral to internal mammary vessels, viz., one inch lateral to the left border of the sternum. To establish free drainage in suppurative pericarditis, the sixth left costal cartilage must be ected and the internal mammary vessels ligatured; the transversus thoracis and the pleural ection are then pushed aside and the pericardium exposed and incised.
The ascending aorta lies behind the sternum, opposite the second and third ribs, d, unless dilated, does not project beyond its right border. The superior border
the aortic arch lies at or a little above the centre of the manubrium sterni ; in ne child the vessel may reach as high as the superior border of the manubrium.
The innominate and left common carotid arteries diverge from either side of the nedian plane between the upper part of the manubrium sterni and the front of he trachea. A pin pushed directly backwards immediately above the middle of Che supra-sternal notch will strike the medial border of the innominate artery a Little below its bifurcation.
The pulmonary artery lies behind the left border of the sternum opposite the second interspace and the second costal cartilage.
The left innominate vein lies behind the superior part of the manubrium sterni, the right behind the medial end of the right clavicle. The superior vena cava lies immediately to the right of the margin of the sternum, opposite the first and second interspaces and the intervening second rib; its opening into the right atrium, behind the third chondro-sternal articulation, corresponds to the centre of the root of the right lung.
art of the
enth costal ise level of addle abdos
Test of the
cavities and valves to the anterior wall of the thorax.
anterior cusp of the tricuspid valve. In Fig. 1099 the greater part of the interventricular septum has been removed, exposing the anterior cusp of
mitral valve. In Fig. 1100 the ascending aorta, anterior cusp of mitral valve, trunk of pulmonary artery, and interauricular
septum have been removed ; the cavities of the left atrium and left ventricle are exposed, also the left
auricle and posterior cusp of mitral valve. R.A. Right atrium.
P.A. Pulmonary artery.
M.V. Mitral valve. R.V. Right ventricle.
P.V. Pulmonary valve.
S.V.C. Superior vena cava L.A. Left atrium.
A. Aortic arch.
P.V. Pulmonary vein. L.A.A. Left auricle.
A.V. Aortic valve.
M. Moderator band. S.V. Interventricular septum. T.V. Tricuspid valve.
ng to the portion setus is
age length of the esophagus in the adult is 10 in. (25 cm.); the n the incisor teeth to its commencement is 6 in.; to the point or it is crossed by the left bronchus, 9 in.; to the esophageal opening ragm, 14 to 15 in.; to the cardiac orifice of the stomach, 16 in. These nts, which are of great importance in diagnosing the seat of csophageal s, should be marked off from below upwards upon all æsophageal d probangs. Posteriorly, the esophagus extends from the level of the ical spine to that of the tenth thoracic, a little to the left of which ation at which the stethoscope is placed in order to hear the sound prothe passage of fluid into the stomach. lly it is important to bear in mind the relation of the csophagus to the trachea and hus, to the left recurrent nerve, to the bronchial and posterior mediastinal glands, scending thoracic aorta, and to the right posterior mediastinal pleura. Ulcers of agus are liable to open into either the trachea, the left bronchus, or the right pleura. eins of the inferior end of the esophagus open partly into the systemic veins and partly portal system ; like those at the inferior end of the rectum they are liable to become in conditions which give rise to chronic interference with the portal circulation. lymph vessels of the upper part of the esophagus 'open into the inferior deep cervical the remainder into the posterior mediastinal glands. csophagus is very distensible in the transverse but not in the antero-posterior direction, he most useful forceps for removing foreign bodies from the æsophagus are those which open -y.
THE ANTERIOR ABDOMINAL WALL.
The configuration of the abdomen varies with the age, sex, obesity, and muscular elopment of the individual. In the child it is wider above than below, while
reverse is the case in the adult female. It is most prominent in the region of e umbilicus, which is situated, normally, below the mid-point between the infraernal notch and the symphysis pubis, usually a little below the level of the highest rt of the iliac crest, and opposite the middle of the body of the fourth lumbar ertebra. In the obese, and especially when the abdominal muscles have lost their one, the umbilical region becomes prominent and more or less pendulous, so that he umbilicus may come to lie considerably below the normal level. In the child at is relatively lower than in the adult, in consequence of the undeveloped state of the pelvis.
In spare subjects the inferior end of the body of the sternum, the xiphoid process, and the costal margin, can readily be traced. The slight depression or notch formed by the seventh costal cartilages and the inferior border of the body of the sternum is termed the infrasternal notch. Below the notch, and bounded on each side by the seventh, eighth, and ninth costal cartilages, is the infracostal angle, which varies considerably according to the shape of the chest; it is relatively wider in the child than the It. The inferior border of the curve of the tenth costal cartilage is easily recognisable, and was selected by Cunningham as the level of the plane of separation (infracostal plane) between the upper and middle abdominal zones.
The anterior abdominal wall is limited below by the fold of the groin and the crest of the pubes. In a spare muscular subject the recti, the furrows corresponding to the inscriptiones tendineæ (0.T. lineæ transversæ) and the supra-umbilical portion of the linea alba, can be readily made out. When the outline of the rectus is not visible the lateral border may be indicated by a line drawn from the tip of the ninth costal cartilage to the mid-point of a line joining the umbilicus and the anterior superior iliac spine, and from thence to the pubic tubercle. In the angle between the lateral border of the rectus and the ninth costal cartilage, on the right side, is a slight triangular depression which overlies the fundus of the gall-bladder
. Between the inferior part of the lateral border of the rectus and the prominence above the anterior part of the iliac crest, caused by the lower