Alternate phrasing: Which movement turns the palm downward?

Alternate phrasing: Which movement turns the palm downward?

• A. Pronation
• B. Supination
• C. Flexion
• D. Extension

Answer: (A)

Pronation is the rotational movement of the forearm that twists the palm to face downward. As the radius rotates around the ulna at the radioulnar joints, the palm moves from facing upward toward the ground. The primary muscles driving this action are the pronator teres and pronator quadratus. Flexion and extension change the angle at a joint (like bending or straightening the elbow or fingers), not the orientation of the palm, so they don’t describe turning the palm downward. Supination, the opposite movement, turns the palm upward. So the motion that turns the palm downward is pronation.

Pronation is the rotational movement of the forearm that twists the palm to face downward. As the radius rotates around the ulna at the radioulnar joints, the palm moves from facing upward toward the ground. The primary muscles driving this action are the pronator teres and pronator quadratus. Flexion and extension change the angle at a joint (like bending or straightening the elbow or fingers), not the orientation of the palm, so they don’t describe turning the palm downward. Supination, the opposite movement, turns the palm upward. So the motion that turns the palm downward is pronation.