What does external rotation refer to in joint movement?

External rotation refers specifically to the movement of a joint that turns the limb outward away from the center of the body. This movement involves rotating the bone around its axis as it moves away from the midline, which is the line that divides the body into right and left halves.

In the context of joint actions, understanding external rotation is vital for analyzing movements in activities such as throwing, kicking, or any action that requires a limb to move away from the central body position.

In distinguishing this from other types of movement, bending a joint inward would typically describe flexion, which reduces the angle between two segments of a limb rather than rotating it. Compressing the joint generally relates to load-bearing actions or stabilization rather than rotational movement. Moving the joint in a circular motion describes circumduction, which is a combination of flexion, extension, abduction, and adduction, resulting in movement that traces a circular path. This is distinct from the unilateral outward movement characterized by external rotation.