What nerves innervate the rectus abdominis muscle?

The rectus abdominis muscle is primarily innervated by the lower thoracic spinal nerves, specifically the thoracoabdominal nerves, which are extensions of the lower thoracic spinal nerves (T7 to T11). These nerves provide motor control to the muscle and also carry sensory information from the skin overlying this area. The function of the rectus abdominis includes flexion of the lumbar spine, as well as contributing to core stability and pressure regulation in the abdominal cavity.

The middle and upper cervical spinal nerves do not innervate the rectus abdominis, as these nerves are responsible for the upper body and neck regions. Similarly, lumbar spinal nerves target the lower back and pelvic regions, and do not provide innervation for the rectus abdominis muscle. Therefore, the correct choice is the one that identifies the appropriate thoracic spinal nerves responsible for its innervation.