subcostalnerv

The subcostal nerve, also known as the twelfth thoracic nerve or T12 nerve, is the anterior ramus of the twelfth thoracic spinal nerve. It originates from the thoracic spinal cord and travels along the inferior border of the twelfth rib. The subcostal nerve runs posteriorly, passing between the diaphragm and the quadratus lumborum muscle. It then courses anteriorly, passing behind the colon and between the transversus abdominis and internal oblique muscles. Its path is generally within the abdominal wall.

The subcostal nerve innervates the skin of the abdominal wall inferior to the umbilicus and the muscles of the abdominal wall, including the transversus abdominis and internal oblique muscles. It contributes to the motor control and sensory perception of this region. Additionally, it provides some sensory innervation to the peritoneum lining the abdominal cavity. Due to its location and innervation of abdominal muscles, the subcostal nerve can be involved in pain referred from abdominal organs or in conditions affecting the abdominal wall. Its close proximity to other abdominal structures means it can be affected by surgical procedures in the region.