Extrinsic shoulder muscles

• Trapezius origin


  occipital bone, nuchal ligament, spinous process of thoracic vertebrae
• Trapezius insertion


  clavicle, acromion, spine of scapula
• Trapezius action of superior, middle, inferior parts

  Superior: elevates scapula

  Middle: retracts scapula

  Inferior: depress scapula

  superior and inferior: rotate glenoid cavity superiorly
• Trapezius innervation

  Cranial nerve 11 - accessory nerve (R/L)
• Deep-Latissimus dorsi origin


  spinous process of inferior thoracic, all lumbar, and saccral vertebrae, ribs 8-12, thoracolumbar fascia
• Latissimus dorsi insertion

  intertubercular sulcus
• latissimus dorsi action

  extend, adduct, medially rotate humerus
• latissimus dorsi innervation

  thoracodorsal nerve
• Deep-rhomboid major origin

  spinous process of T2-T5
• Rhomboid major insertion

  medial border of scapula
• rhomboid major action

  adduct the scapula, tilt glenoid cavity inferiorly
• Rhomboid major innervation

  Dorsal scapular nerve
• Deep- rhomboid minor origin

  nuchal ligament, spinous process (C7-T1)
• Rhomboid minor insertion

  medial border of scapula
• Rhomboid minor action

  adduct the scapula, tilt glenoid cavity inferiorly
• Rhomboid minor innervation

  dorsal scapular nerve