Flexion and extension occur in which plane?

Flexion and extension are movements that occur primarily in the sagittal plane. When a body part is flexed, it is typically brought closer to the body or a specific joint, while extension moves it away from that position, increasing the angle between body parts. For instance, bending the elbow into a flexed position decreases the angle at the elbow joint, and straightening it out into an extended position increases that angle.

The sagittal plane divides the body into left and right sections, and movements occurring in this plane, such as walking or nodding the head, predominantly involve flexion and extension. Understanding these movements in relation to the sagittal plane is fundamental in biomechanics, as many functional activities depend on these actions for performance and stability during various motions.