How many primary arthrokinematic movements are there?

• A. 3
• B. 5
• C. 7
• D. 9

Answer: (A)

The correct response identifies that there are three primary arthrokinematic movements: roll, slide (or glide), and spin. These movements describe how the surfaces of two bones interact in a joint during motion.

Roll occurs when a new part of one surface comes into contact with a new part of another surface, similar to the movement of a tire rolling on the ground. Slide involves one surface moving over another in a linear manner, akin to a book sliding across a table. Spin involves one surface rotating around a stationary axis, much like how a top spins on a surface.

These three movements are fundamental to understanding joint mechanics and are critical for analyzing how different joints in the body function during dynamic activities. Understanding arthrokinematics is essential for practitioners in clinical biomechanics, as it aids in diagnosing joint dysfunction and planning appropriate interventions or treatments.