This document provides details on important anatomical landmarks for surface marking of the thorax, including the heart, lungs, blood vessels, and trachea. It describes the locations of landmarks like the sternal angle, apex of the heart, borders of the lungs, arch of the aorta, and trachea by identifying the points that define lines connecting anatomical structures. Instructions are given for counting ribs and intercostal spaces and outlining visceral organs based on palpable bony landmarks on the chest wall.

1. Surface Marking of Thorax
Dr. Mushfiqul Hoque
Lecturer
Dhaka National Medical College

2. Important Landmarks to
Know

3. Sternal Angle
A palpable and sometimes visible
transverse ridge at the junction
of menubrium sterni and body of
the sternum. On each side it
articulates with the second
costal cartilage.

4. Counting of ribs and intercostal space
From sternal angle
On both sides of the sternal
angle there are the second costal
cartilages
Below that there is the 2nd
intercostal space

5. Apex of heart
Left fifth intercostal space, 9 cm
away from midline, slightly
below and medial to the left
nipple, slightly medial to the
midclavicular line.

6. Viscera

7. Heart

8. Right Border of Heart
Right border of the heart is drawn by a
line joining the following points:
1. A point at the upper border of the
third right costal cartilage 0.8 cm
from the sternal margin
2. A point on 4th costal cartilage 3.7cm
from the sternal margin.
3. A point at the lower border of the
sixth right costal cartilage close to
the sternal margin.

9. Inferior Border of Heart
Lower border of the heart is drawn by a
line joining the following points:
1. A point at the lower border of the
sixth right costal cartilage close to
the sternal margin.
2. A point at the xiphi-sternal joint
3. A point at the apex of the heart in
the left fifth intercostal space 9 cm
from the midsternal line.

10. Left Border of Heart
Left border of the heart is drawn
by a line joining the following
points:
1. A point at the lower border of
the second left costal cartilage
about 1.2 cm from the sternal
margin.
2. A point at the apex of the
heart in the left fifth
intercostal space 9 cm from
the midsternal line.

11. Lungs

12. Apex of the Lung
Apex of the Lung is drawn by a line joining
the following points:
1. A point at the sterno-clavicular joint
2. A point on the clavicle at the junction
of medial one-third and lateral two-
thirds
3. A point 2.5 cm above the midpoint
between point 1 and 2

13. Anterior Border of the Right Lung
Anterior Border of the Right Lung is drawn
by a line joining the following points:
1. A point about 2.5 cm above the right
clavicle at the midpoint
between medial 1/3 and sternal end of
clavicle
2. A point at the sternoclavicular joint.
3. A point in the median plane at the
sternal angle
4. A point in the median plane just above
the xiphi-sternal joint.

14. Anterior Border of the Left Lung
Anterior Border of the Left Lung is drawn by a line joining the following points:
1. A point about 2.5 cm above the left clavicle at the midpoint between medial
1/3 and sternal end of clavicle
2. A point at the left sternoclavicular joint.
3. A point in the median plane at the sternal angle
4. A point in the median plane at the level of 4th costal cartilage
5. A point at the lower border of the left 4th costal cartilage 3.5 cm away from
the median plane
6. A point on the left 6th costal cartilage 4 cm away from the median plane

15. Anterior Border of the Left Lung
Anterior Border of the Left Lung is drawn
by a line joining the following points:
1. A point about 2.5 cm above the
left clavicle at
the midpoint between medial 1/3
and sternal end of clavicle
2. A point at the left sternoclavicular
joint.
3. A point in the median plane at the
sternal angle

16. Anterior Border of the Left Lung
Anterior Border of the Left Lung is drawn
by a line joining the following points:
1. A point in the median plane at the
level of 4th costal cartilage
2. A point at the lower border of the
left 4th costal cartilage 3.5 cm away
from the median plane
3. A point on the left 6th costal
cartilage 4 cm away from the
median plane

17. Lower Border of the Right Lung
Lower Border of the right Lung is drawn
by a line joining the following points:
1. A point at the xiphi-sternal joint
2. A point on the 6th rib on the mid
clavicular line
3. A point on the 8th rib on the mid
axillary line
4. A point 2 cm lateral to the 10th
thoracic spine

18. Lower Border of the Right Lung
Lower Border of the right Lung is drawn
by a line joining the following points:
1. A point at the xiphi-sternal joint
2. A point on the 6th rib on the mid
clavicular line
3. A point on the 8th rib on the mid
axillary line
4. A point 2 cm lateral to the 10th
thoracic spine

19. Lower Border of the Left Lung
Lower Border of the Left Lung is drawn
by a line joining the following points:
1. A point at the left sixth costal
cartilage 4 cm away from the
midline
2. A point on the 6th rib on the mid
clavicular line
3. A point on the 8th rib on the mid
axillary line
4. A point 2 cm lateral to the 10th
thoracic spine

20. Lower Border of the Left Lung
Lower Border of the Left Lung is drawn
by a line joining the following points:
1. A point at the left sixth costal
cartilage 4 cm away from the
midline
2. A point on the 6th rib on the mid
clavicular line
3. A point on the 8th rib on the mid
axillary line
4. A point 2 cm lateral to the 10th
thoracic spine

21. Posterior Border of the Lung
Posterior Border of the Lung is drawn by
a line joining the following points:
1. A point at 2 cm lateral to the seventh
cervical spine
2. A point at 2 cm lateral to the 10th
thoracic spine

22. Oblique fissure of the Lung
Oblique fissure of the Lung is drawn by a
line joining the following points:
1. A point at 2 cm lateral to the second
thoracic spine.
2. A point 3 cm lateral to and at the
level of nipple
3. A point on the 6th costal cartilage
7.5 cm lateral to the median plane

23. Oblique fissure of the Lung
Oblique fissure of the Lung is drawn by a
line joining the following points:
1. A point at 2 cm lateral to the second
thoracic spine.
2. A point 3 cm lateral to and at the
level of nipple
3. A point on the 6th costal cartilage
7.5 cm lateral to the median plane

24. Vessel

25. Arch of the Aorta
Arch of Aorta is drawn by a
curved line joining the following
points:
1. begins at the right end of the
sternal angle
2. arches upwards and to the left
through the centre of the
manubrium
3. ends at the sternal end of the
left second costal cartilage.

26. Trachea
Trachea is marked by two
parallel lines 2 cm apart,
drawn from the lower border
of the cricoid cartilage (2 cm
below the thyroid notch) to
the sternal angle, inclining
slightly to the right

27. End of discussion
questions?