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.
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
Related Posts
Aching and Burning in the mid back
Quadratus Lumborum and Serratus Posterior Inferior – Neuromuscular Massage Protocol
Self Care – Breathing exercise for upper back pain
Self Care – Relief from Coughing
Self-Care – Burning and Aching Mid-back Pain
Serratus Posterior Inferior – Massage Therapy Notes
Thoracolumbar Release with AO-45
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.
Cranio Cradle Cup
This mug has classic, colorful illustrations of the craniosacral system and vault hold #3. It makes a great gift and conversation piece.
Tony Preston has a practice in Atlanta, Georgia, where he sees clients. He has written materials and instructed classes since the mid-90s. This includes anatomy, trigger points, cranial, and neuromuscular.
Question? Comment? Typo?
integrativeworks@gmail.com
Follow us on Instagram
*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 include more patterns with better self-care. Meanwhile, there may be formatting, content presentation, and readability inconsistencies. Until we get older posts updated, please excuse our mess.