in cross section showing partial cushioning fig1 c is a frontal cross sectional view illustrating full cushioning two or more retaining cylinders may also be used to reduce the shear on the solid piece of silicone rubber elastomer or hydrogel type material fig1 a is a top down view of an embodiment showing opposing retaining cylinders on either side of a central resilient member fig1 b is a side view drawing in cross section showing partial cushioning of the device of fig1 a fig1 c is a side view drawing in partial cross section illustrating the embodiment of fig1 a and 11b providing a full cushioning and reduced shear capability reference is now made to fig1 a which is an a p view of the embodiment of the invention wherein the end plates of adr may contain hollow keels on the vertebral side fig1 b is a lateral view and fig1 c is a top down view illustrating the bone ingrowth area the vertebrae would be osteotomized to make room for the keels the bone from the osteomity sites would be morselized and placed inside the hollow keels the morselized bone would promote ingrowth into the end plates of the adr much like hollow cages promote bone ingrowth fig1 is a cross section of an embodiment with multiple pistons connected to the top plate via rod much like the design of rods that connect pistons to a.