The pyramidalis muscle is a paired, triangular muscle, which lies in the lower portion of the anterior abdominal wall. It arises from the pubic bone in front of the insertion of the rectus abdominis. Then its fibers converge and runs upwards medially to be inserted into the lower parts of the linea alba at various levels.
Both muscles, the pyramidalis and the rectus abdominis are enclosed in the sheath of latter one, which is formed by the aponeuroses of the broad abdominal muscles.
Action
Together with the rectus abdominis, the pyramidalis muscle flexes the trunk (as when you do sit-ups while working out).
Innervation
This abdominal muscle is innervated by the lumbar (T5 to T2; L1) and intercostal nerves.
Blood Supply
The pyramidalis is supplied by the inferior epigastric artery, which arises from the external iliac, and the cremasteric artery, which is a pubic branch of the inferior epigastric.
 |
| Above, the abdominal muscles, with the Pyramidalis lying at the bottom of the anterior abdominal wall on the midline. |
0 Comments