Home » Anatomy » Torso Muscles » intrinsic Back Muscles » Serratus Posterior Inferior – Functional Anatomy

Serratus Posterior Inferior – Functional Anatomy

Serratus Posterior Inferior

Origin

The spinous processes of T11-L2

Insertion

the inferior border of the last four ribs, just lateral to the angle of the rib

Function

Its position indicates that it should extend and rotate the trunk, as well as assist in breathing, especially when breathing is forceful, or the trunk is contorted. It is, however, hard to find electromyographical studies that have determined when this muscle contracts.

Breathing muscles

Attachment Details

This muscle is the most superficial of the intrinsic back muscles and straps across the erectors, levator costae, and intrinsic spine muscles.

Serratus posterior inferior originates on T11-L2 and inserts on ribs 9-12, trapping the 9th and 10th thoracic vertebrae. There is a thin sheet of connective tissue that continues from the short bellies of the muscle on the rib to the supraspinous ligament over the spinous process.

Functional Considerations

Serratus posterior inferior produces pain in labored breathing, coughing, and vomiting. However, several studies conclude that it is not involved in breathing.

The two serratus posterior muscles are positioned in a layer between the intrinsic back muscles and the extrinsic back muscles. They strap over the spinal erectors, gathering the muscle bellies medially.

Anomalies, Etc.

A number of studies investigate the anomalies in this muscle. They all seem to conclude that there are no notable differences from one side to another. The only notable anomaly is the width of the aponeurotic strip that connects the muscle bellies to the spinous processes and ligaments.

Wikipedia entry for serratus posterior inferior

Support Integrative Works to
stay independent
and produce great content.

You can subscribe to our community on Patreon. You will get links to free content and access to exclusive content not seen on this site. In addition, we will be posting anatomy illustrations, treatment notes, and sections from our manuals not found on this site. Thank you so much for being so supportive.


Featured Post

Does Your Shoulder Hurt From the Covid-19 Vaccine?

This post offers quick, lasting relief from the pain in your shoulder that came from the vaccine. You will need an ice cube and about 2 minutes.

Tony Preston has a practice in Atlanta, Georgia, where he sees clients. He has written and taught about anatomy, trigger points, and cranial therapies since the mid-90s.

Question? Comment? Typo?
IntegrativeWorks.com
(404) 226-1363
[email protected]

*This site is undergoing significant changes. We are reformatting and expanding the posts to make them easier to read. The result will also be more accessible and will include more patterns with better self-care. In the meanwhile, there may be inconsistencies in formatting, content presentation, and readability. Until we get older posts updated, please excuse our mess.