One or more rigid components associated with an articulating bone are used to encase, encapsulate, contain, or otherwise protect a compressible/resilient member. The embodiments are applicable not only to artificial disc replacement (ADR) devices, but also to joint situations including total knee and hip arthroplasty. The cushion elements in the preferred embodiments include synthetic rubbers, hydrogels, elastomers, and other polymeric materials such as viscoelastic polymers and foam polyurethanes. The invention effectively combines the advantages of such materials (cushioning, shape memory, and expansion after insertion in the case of hydrogels), while providing increased protection, particularly the elimination of shear stresses. When applied to an ADR, the invention also minimizes the risk of extrusion.