Serratus Posterior Muscles are-
Serratus Posterior Superior
Serratus Posterior Inferior
Serratus Posterior Superior
The serratus posterior superior is lying deep to the rhomboid muscles on the upper back.
Attachments:
Origin: The lower part of the ligamentum nuchae, and the cervical and thoracic spines (usually C7 – T3).
Insertion: The fibers of the Serratus Posterior Superior pass in an inferolateral direction, attaching to ribs 2-5.
Nerve Supply: Intercostal nerves.
Actions: Elevates ribs 2-5.
Serratus Posterior Inferior
The serratus posterior inferior muscle is lies underneath the latissimus dorsi.
Attachments:
Origin: Originates from the thoracic and lumbar spines (usually T11 – L3).
Insertion: The muscle fibers pass in a superolateral direction, attaching to ribs 9-12.
Nerve Supply: Intercostal nerves.
Actions: Depresses thoracic ribs 9-12.