Which nerve provides innervation to the costal pleura?

• A. Phrenic nerve
• B. Intercostal nerves
• C. Vagus nerve
• D. Glossopharyngeal nerve

Answer: (B)

Costal pleura is part of the parietal pleura lining the inner chest wall and has somatic sensory fibers supplied by the intercostal nerves. These nerves travel in the intercostal spaces and provide sharp, well-localized sensation from the costal pleura, so pleural pain here is felt along the chest wall. The phrenic nerve, by contrast, supplies sensory innervation to the central diaphragmatic and mediastinal pleura, not the costal portion. The vagus nerve carries autonomic innervation to thoracic viscera with some visceral afferents, but not the somatic innervation of the costal pleura. The glossopharyngeal nerve has no role in thoracic pleural innervation. Thus, intercostal nerves are responsible for innervating the costal pleura.