External Rotation

External rotation (or lateral rotation) is rotation away from the center of the body.

The muscles of external rotation include:

  • of arm/humerus at shoulder
    • Deltoid muscle
    • Infraspinatus
    • Teres minor
  • of thigh/femur at hip
    • Gluteus maximus
    • Lateral rotator group
      • piriformis
      • gemellus superior
      • obturator internus
      • gemellus inferior
      • obturator externus
      • quadratus femoris
    • Sartorius
  • of leg at knee
    • Biceps femoris
  • of eyeball (motion is also called "extorsion" or excyclotorsion)
    • Inferior rectus muscle
    • Inferior oblique muscle

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