Intercostal nerves arise from dorsal and ventral rami of the thoracic spinal nerves to innervate the muscles, in addition to providing sensation to the parietal pleura. Each nerve enters the correlated intercostal space and travels alongside the intercostal vessels.
The typical orientation of the neurovascular bundle is vein - artery - nerve from superior to inferior. This orientation is important to understand, as injury to the intercostal nerve may occur with placement of chest tubes or thoracotomy procedures.
The intercostal nerves are typically groups into typical and atypical nerves related to distinctions in anatomic distribution.
References:
Glenesk NL, Rahman S, Lopez PP. Anatomy, Thorax, Intercostal Nerves. [Updated 2020 May 23]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK538238/
