Subcostal nerve

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

Subcostal nerve

The subcostal nerve is the anterior division of the 12th thoracic nerve (T12). It is a mixed motor and sensory nerve that helps form the lumbar plexus. It runs along the bottom edge of the 12th rib and often sends a branch to the first lumbar nerve. It passes under the lateral lumbocostal arch and then in front of the quadratus lumborum, continuing forward between the transversus abdominis and internal oblique to supply the abdominal wall in a pattern similar to the lower intercostal nerves. It communicates with the iliohypogastric and ilioinguinal nerves, and gives branches to the pyramidalis muscle and to the quadratus lumborum. It also has a lateral cutaneous branch that provides sensation to the skin over the hip.