What defines the term external rotation?

External rotation refers to the movement of a joint that results in a turning outward motion. This action typically involves the rotation of a limb or body part away from the midline of the body. For instance, in the case of the shoulder or hip joints, external rotation allows the arm or leg to move away from the central axis, facilitating a range of motions and activities.

In practical terms, when the arm is externally rotated, the palm of the hand turns to face forward or away from the body, which contrasts with internal rotation, where the hand turns inward toward the midline. Understanding this concept is crucial in fields like anatomy, physical therapy, and movement science because it helps health professionals identify and address functional movement patterns or limitations in patients.