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
Famous quotes containing the words external and/or rotation:
“All violent feelings have the same effect. They produce in us a falseness in all our impressions of external things, which I would generally characterize as the “pathetic fallacy.””
—John Ruskin (1819–1900)
“The lazy manage to keep up with the earth’s rotation just as well as the industrious.”
—Mason Cooley (b. 1927)