Longissimus Thoracis

Where Is the Longissimus Thoracis?


What are the Symptoms of a Longissimus Thoracis tear or strain?

Pain in this muscle can be felt on the upper part of the Longissimus Thoracis as if something is stuck or out of place and needs to be popped in place. There will always be a nagging pain under the shoulder blade.

When this muscle is tight and imbalanced an individual will be pulled downward to one side.


What is The Function of the Longissimus Thoracis?

Extension of the thoracic spine, lateral flexion of the thoracic spine, extension of the lumbar spine, lateral flexion of the lumbar spine.

  • Straightens (extends) the back (vertebral column)
  • Helps in tilting the pelvis
  • Assists in deep diaphragm breath.


Origin and Insertion of Longissimus Thoracis

The common broad, thick tendon with Iliocostalis Lumborum, fibers from the transverse and mamillary processes of the lumbar vertebrae and lumbrosacral aponeurosis.

Transverse processes of T1 – T12; between tubercles and angles of lower 9 to 10 ribs.