Teres Major

• Teres Major:

  • Thick muscle forming part of the posterior aspect of the axilla with Latissimus dorsi

  
• O (origin)

  • Dorsal surface of the inferior angle of scapular, below teres minor

  A) Teres Major

  
• R (direction)

  • Upwards, anteriorly and laterally

  A) Teres Major

  
• I (insertion)

  • Fibres attach via a broad flat tendon to the medial lip of the intertubercular groove of humerus (tendon separated from latissimus dorsi tendon by a bursa)

  A) Teres Major

  
• A (actions)

  • Adducts and medial rotates glenohumeral joint
  • may also assist with extension of the flexed shoulder

  A) Teres Major

  
• NS (nerve supply)

  • Lower subscapular nerve (C5, C6)

  A) Teres Major

  
• Function:

  • resists upward displacement of the head of humerus during active contraction of deltoid