Abstract: A mobile diagnostic assembly (20) of the type for supporting a patient in a prone position along an examination surface includes a support frame (22) having a top (26) extending between a front edge (38) and a rear edge (40) and defining at least one opening (48) for receiving pendant breasts of the patient in the prone position. The support frame (22) is movable to a testing position for disposing the rear edge (40) adjacent the examination surface. A flap (50) extends from the rear edge of the top for overlaying an examination surface in the testing position to support the prone patient along the examination surface and said flap and said top to prevent movement of the support frame relative to the examination surface. A pivot (54) is disposed between the flap and the top for establishing rotation of the flap from the testing position to cover said top.