Human Anatomy Vol 1

with a height of about 2.5 cm above the clavicle

(Fig. 21.1). Pleura lies in the root of neck on both sides.

The anterior margin, the costomediastinal line of

pleural reflection is as follows: On the dght side, it

extends from the sternoclavicular joint downwards and

medially to the midpoint of the sternal angle. From here

it continues vertically downwards to the midpoint of

the xiphisternal joint crosses to right of xiphicostal

angle. On the left side, the line follows the same course

up to the level of the fourth costal cartilage. It then

arches outwards and descends along the stemal margin

up to the sixth costal cartilage.

The inferior margin, or the costodiaphragmatic line

of pleural reflection passes laterally from the lower limit

of its anterior margin, so that it crosses the eighth rib in

the midclavicular line, the tenth rib in the midaxillary

line, and the twelfth rib at the lateral border of the

sacrospinalis muscle (Frg. 21.2). Further it passes

horizontally a little below the 12th rib to the lower

Midclavicular line

Clavicle

Midaxillary line

Left pleural sac

Level of fourth costal cartilage

Thoracic wall

Level of sixth costal cartilage

Costal margin

Twelfth rib

Lower border of body of vertebra Tl 2 or upper

INTRODUCTION

Surface marking is the projection of deeper structures

on the surface of body.

The bony and soft tissue surface landmarks have been

described in Chapter 12.

The surface marking of important structures is

described here.

o Pleura (Fig.21.1)

o Lungs (Figs 2L.2 to 21.4)

e Heart (Fig.21.5)

. Cardiac valves (Fi9.21,$)

Surfoce Morking of Poilelol Pleuro

The ceraical pleura is represented by a curved line
forming a dome over the medial one-third of the clavicle

Level of upper border of body

of vertebral Tl or spine of C7

Sternal angle

Right pleural sac

Xiphisternal joint

Right xiphicostal angle

Level of eighth rib

Level of tenth rib

border of spine of the same vertebra

Fig.21 "1: Surface marking of the parietal pleura

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