The integrity of the symphysis pubis is maintained by strong ligaments, anteriorly, posteriorly, superiorly and inferiorly. Consequently, movement at the symphysis pubis is quite small in the absence of pathology.
A normal superior shearing movement will occur if one-legged standing is maintained for several minutes. However, after standing on the opposite leg, or with prolonged standing on both legs, equal height of the superior aspect of the symphysis pubis will be restored to visualize this motion with time speeded up -- Click here to view a close-up of the same motion). Shearing forces will also occur during the dynamic walking cycle (Click here to visualize this motion), with superior shearing occuring on the weight bearing side. Restriction of normal symmetry at the symphysis pubis results in altered anterior and posterior innominate rotation during walking.