Latissimus Dorsi
The Latissimus dorsi muscle is one of the largest in the body. It is a powerful extensor muscle of the arm and is used extensively in chinning and climbing. They are commonly known at the lats.
Origin
- Posterior crest of the ilium (via the Thoracolumbar fascia).
- Posterior sacrum.
- Spinous processes of T7-L5.
Insertion
- Intertubercular groove (between the greater and lesser tuberosities) of the humerus.
Actions
- Extension.
- Internal rotation.
- Adduction.
Innervation
- Thoracodorsal nerve.
Daily uses
- Pushing on the arms of a chair when standing up.
Example strengthening exercises
- Lat pull down using a resistance band.
Example stretches
- Latissimus dorsi stretch I.
- Latissimus dorsi stretch II.
Related injuries
- Tight muscles in the upper back and neck.
Related muscles
- Teres major.
