Which statement defines extension?

Which statement defines extension?

• A. Movement toward the midline
• B. Movement away from the midline
• C. Increasing angle at joint
• D. Decreasing angle at joint

Answer: (C)

Extension is the action of increasing the angle at a joint, typically by straightening a bent limb. For example, when you straighten the elbow, the angle between the upper arm and forearm becomes larger. This is the opposite of flexion, which decreases the angle as a joint bends. The other descriptions relate to moving toward or away from the midline (adduction and abduction), not to changing the joint’s angle. So, increasing the angle at the joint best defines extension.

Extension is the action of increasing the angle at a joint, typically by straightening a bent limb. For example, when you straighten the elbow, the angle between the upper arm and forearm becomes larger. This is the opposite of flexion, which decreases the angle as a joint bends. The other descriptions relate to moving toward or away from the midline (adduction and abduction), not to changing the joint’s angle. So, increasing the angle at the joint best defines extension.