Manifold structures, systems, and methods are disclosed that include using longitudinal members and one or more shaped projections to cause microstrain at a tissue site. In one instance a manifold structure includes a plurality of spaced longitudinal members and at least one shaped projection coupled to at least one of the plurality of longitudinal members for creating a microstrain at a tissue site. The at least one shaped projection includes a columnar member having a distal end and includes an enlarged member positioned at the distal end of the columnar member. The columnar member has a first outer diameter (D.sub.1) and the enlarged member has a second outer diameter (D.sub.2). The second outer diameter of the enlarged member is greater than the first outer diameter of the columnar member (D.sub.2>D.sub.1). Other systems, methods, and structures are presented.