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

  • Shoulder extension. 
  • Internal rotation.  
  • Adduction.

Innervation

  • Thoracodorsal nerve. 

Daily uses

  • Pushing on the arms of a chair when standing up. 

Example strengthening exercises

Example stretches

Related injuries

Related muscles