Expansion
Parietal pleura is somatically innervated and painful; visceral pleura is autonomic and insensitive
Expansion
- Parietal pleura - somatic innervation from the intercostal and phrenic nerves. Sensitive to pain, temperature, touch and pressure
- Visceral pleura - autonomic innervation from the pulmonary plexus. Sensitive only to stretch, and not to pain
This asymmetry explains a great deal of clinical medicine. A large central lung tumour can grow silently until it reaches the chest wall, at which point pain appears abruptly. A small peripheral pneumonia touching the pleura hurts far more than its size suggests.
It also explains the referral pattern: pain from the costal pleura is felt over the chest wall in the corresponding dermatome, while pain from the central diaphragmatic pleura is felt in the shoulder tip through C3, C4 and C5.