A prosthesis for replacing a native disc between first and second adjacent vertebral bodies. The prosthesis includes a compliant element having a first composition and a geometry for providing a plurality of element stiffnesses for the compliant element substantially matching spatial stiffnesses of the native disc. The prosthesis also includes an upper plate of the first or a second composition, the upper plate having opposed inner and outer surfaces, the upper plate inner surface having a first retaining structure for affixing a position of the first end of the compliant element, and a lower plate of the first or a second composition, the lower plate having opposed inner and outer surfaces, the lower plate inner surface having a second retaining structure for affixing a position of the second end of the compliant element.