An implantable prosthesis is provided for repairing an anatomical defect, such as a tissue or muscle defect, that promotes tissue of muscle ingrowth into the prosthesis and subsequently strengthens the area of the defect. The prosthesis is easy to manipulate and may be designed to minimize the incidence of postoperative adhesions between a portion of the prosthesis and surrounding tissue or organs. The prosthesis may include one or more layers of biologically compatible material that is suitable for repairing a defect. The prosthesis may include a support assembly to facilitate manipulation and deployment of the prosthesis. The support assembly may include a stiffening member that is surrounded by material that separates the stiffening member from the layer of material. The stiffening member may be located in a sleeve of material, such as mesh fabric. The stiffening member may be formed from a resorbable material.
