The |serratus posterior superior| and inferior muscles lie deep on the front part of the neck. The |serratus posterior superior| is a thin, flat, quadrilateral muscle that extends from the neck to the third, fourth, and fifth |ribs|. The serratus posterior inferior is broader than the |serratus posterior superior| and extends to the four lower |ribs|. Both muscles are respiratory muscle. The |serratus posterior superior| elevates the |ribs| as you inhale and the serratus posterior inferior pulls the |ribs| down and back to exhale.
