Surface anatomy (lung)

The apices of the lung extend about three centimetres above the medial third of the clavicles then project inferolaterally to the junction of medial and middle thirds of clavicle. Anteriorly, the hila lie at the level of costal cartilages 3-4; this is vertebral level T5-7.

The inferior margins of the lung are:

• T6 - mid-clavicular line
• T8 - mid-axillary line
• T10 - posteriorly At each point, the parietal pleural reflections sit inferiorly by approximately 2 ribs. However, this level varies with respiratory phase.

The anterior margins are different on each side and largely follow the lines of parietal pleural reflection:

• on the right:
  • deep to the right side of the sternum between the second and fourth costal cartilages inferiolaterally to the level of
  • the deep surface of the sixth right intercostal cartilage
• on the left:
  • deep to the sternum near the midline inferiorly between the levels of costal cartilages 2 and 4
  • displaced laterally and more obliquely than left side to a point about 3cm lateral to the left sternal edge at the upper margin of the sixth costal cartilage
  • the space created by the lateral deviation of pleura and lung on the left side is termed the cardiac notch

The surface markings of the fissures of the lungs are described in the submenu. A general point about the lobes produced by the fissures is that the great majority of the surface area:

• anteriorly is covered by upper and middle lobes on the right and upper lobe alone on the left
• posteriorly is covered by lower lobes on both sides