What is rotation?

What is rotation?

• A. Movement of a bone around its longitudinal axis
• B. Movement of a bone toward the midline
• C. Movement of a joint to flex
• D. Shortening of muscle

Answer: (A)

Rotation is turning a bone around its own long axis, twisting the bone in place without changing its overall position. This is the motion you see when you turn the head side to side or rotate the arm at the shoulder so the palm faces inward or outward (internal/medial and external/lateral rotation). Moving toward the midline describes adduction, flexing describes bending a joint to decrease its angle, and shortening of a muscle refers to contraction. All of those are different kinds of movement from rotation.

Rotation is turning a bone around its own long axis, twisting the bone in place without changing its overall position. This is the motion you see when you turn the head side to side or rotate the arm at the shoulder so the palm faces inward or outward (internal/medial and external/lateral rotation).

Moving toward the midline describes adduction, flexing describes bending a joint to decrease its angle, and shortening of a muscle refers to contraction. All of those are different kinds of movement from rotation.