An example medical device for treating a body lumen is disclosed. The medical device includes an expandable scaffold positionable within a body lumen wherein the body lumen has an inner surface. The medical device also includes a support member extending circumferentially around and attached to an outer surface of the expandable scaffold. The support member is configured to be positioned between the outer surface of the expandable scaffold and the inner surface of the body lumen and at least a portion of the support member is configured to shift relative to the inner surface of the body lumen. Further, shifting the support member shifts the scaffold longitudinally from a first position within the body lumen to a second position within the body lumen with the scaffold in an expanded state to accommodate peristalsis.
