Skeletal System A&P Practice Test

Retraction describes moving a part backward. It’s a posterior movement of a body part toward the back or toward the spine in many joints. For example, pulling the jaw straight back or squeezing the shoulder blades together toward the spine are both retractions. This is different from extension, which straightens or lengthens a joint (increasing the angle), and from flexion, which bends a joint (decreases the angle). Abduction moves a limb away from the midline, and protraction would be a forward (antierior) movement. So, the backward movement described is retraction.