Abstract: Improved polymeric orthopaedic compositions are disclosed wherein sized, functional fibers are incorporated into a physiologically acceptable matrix. The compositions of the invention can be fabricated in the form of particulate powders adapted for reinforcment of bone cements, continuous media for such cements, and orthopaedic implant coatings. A complete implant attachment system is also provided, made up of a fiber reinforced implant coating, and a compatible fiber-reinforced cement. In preferred forms, the fibers have a layer of sizing thereover which is chemically joined both to the surface of the fibers and to the surrounding matrix, and the fibers are present at a level of at least about 6 volume percent. If desired, sized radiopaque particles may be incorporated into the compositions of the invention. The fibers are advantageously polymeric in nature and of intermediate stiffness, whereas the matrix fraction is preferably polymethylmethacrylate.