A system for providing intramedullary guidance to implant an ankle prosthesis, comprises a first tool sized and configured to form a passage between a tibia (10) and a talus (20), a second tool sized and configured to create an intramedullary canal (12) in a distal end of said tibia, a plurality of modular tibial rod components (102, 104, 106) sized and configured to be disposed in said intramedullary canal (12) and connected to each other in situ to form a single tibial rod component, a base modular component (106) on a distal end of said tibial rod component configured to engage an alignment guide (200), and said alignment guide (200) configured to translate coronal, transverse, and sagittal adjustments from the alignment guide (200) to a cutting guide.
