Which term describes straightening a joint?

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

Answer: (C)

Straightening a joint increases the angle between the two bones, returning toward the limb’s straight or anatomical position. This movement is called extension. When a joint bends, the angle decreases, which is flexion, so extension and flexion are opposite actions. Pronation involves rotating the forearm so the palm faces downward, not changing the joint’s angle. Circumduction describes a circular, cone-shaped movement that combines several actions (flexion, extension, abduction, and adduction) rather than simply straightening a joint. In practice, recognizing extension helps you assess or facilitate a straightened position during treatment and stretching while being mindful of any hyperextension.