when the angle is open to the back; (2) the anteroposterior (sagittal axis, on which abduction and adduction are accomplished; and (3) the vertical axis, on whose circumference inward and outward rotation occurs. Circumduction takes place when movement changes from one axis to another. The ball-and-socket joint is the most freely mobile joint. Since the range of movement depends on the difference in the extent of the articular surfaces, the articular fossa in such a joint is small in comparison to the size of the head. Medical Coding Services will help in all these medical coding process for the payments.