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:
“Language disguises the thought; so that from the external form of the clothes one cannot infer the form of the thought they clothe, because the external form of the clothes is constructed with quite another object than to let the form of the body be recognized.”
—Ludwig Wittgenstein (1889–1951)
“The lazy manage to keep up with the earth’s rotation just as well as the industrious.”
—Mason Cooley (b. 1927)