Comprehensive Osteopathic Medical Licensing Examination (COMLEX USA) Practice

Which motion occurs in the transverse plane with a vertical axis?

1. Flexion

2. Rotation

3. Asymmetry

4. Extension

The correct answer is: Rotation

The motion that occurs in the transverse plane with a vertical axis is rotation. In the biomechanical context, the transverse plane divides the body into upper and lower halves, and motions in this plane primarily involve rotational movements. When thinking about the vertical axis, it's essential to understand that rotation occurs around this axis, enabling body parts to pivot or turn. For example, during activities like twisting the torso or turning the head, the motion is facilitated by rotation through the transverse plane. In contrast, flexion and extension occur in the sagittal plane, involving movements that increase or decrease the angle between body parts, while asymmetry is not a specific type of movement but rather a description of body position or alignment. Thus, rotation is the correct answer as it distinctly matches the definition of a motion in the transverse plane surrounding a vertical axis.