Surface Anatomy of Pleura
Mnemonic: 2, 4, 6, 8, 10, 12 rule
1. Starts about 2 cm above the midpoint of medial 1/3 of clavicle.
2. Meet in the midline at rib 2.
3. Left side reaches sternal line at rib 4 (to make room for heart).
4. Right side reaches sternal line at rib 6.
5. Both cross rib 8 in midclavicular line.
6. Both cross rib 10 in mid-axillary line.
7. Both cross mid-scapular line (posteriorly) in rib 12.
Surface Anatomy of Lungs
1. Apex, Anterior border and Posterior border of lungs: Correspond to the lines of pleura but are slightly away from median plane
2. Inferior margin:
Below rib 6, the lungs extend to two rib spaces less than pleura (i.e. opposite to rib 6 mid-clavicular line, rib 8 mid-axillary line and rib 10 posteriorly). The parietal pleura extends a further two rib spaces inferiorly than the inferior lung edge to allow space for lung expansion.
| Level | Parietal pleura | Lungs |
| Midclavicular line | 8th rib | 6th rib |
| Midaxillary line | 10th rib | 8th rib |
| Midscapular line | 12th rib | 10th rib |
3. Oblique fissure: T3 to 6th costal cartilage
4. Transverse fissure (right lung only): Right 4th costal cartilage (sternal edge) to Oblique fissure