A polyaxial ankle joint replacement implant has a dual bearing component situated between a tibia attachment component and a talus attachment component. The dual bearing component includes a plate, a superior bearing bonded to the plate and providing translation with the tibia attachment component, and an inferior bearing providing translation with the talus attachment component. The tibia attachment component has peripheral transversely extending flanges that limit movement relative to the superior bearing and vice versa. The plate has a flange on its inferior surface that receives an opening in the inferior bearing, the size of the opening determining an amount of lateral translation. The plate also has unobstructed posterior and/or anterior ends that permit removal and replacement of the inferior bearing post-operative. This allows change from a mobile to fixed bearing (and vice versa), as well as a change in amount of degrees of translation.