The German Ankle System is a three-component prosthesis allowing rotation around each of the three possible movement axes. The talar component of this prosthesis includes side borders to keep the mobile bearing in position, which may prevent inlay dislocation. Both metallic components have BONIT© coating (porous coating with titanium plasma sprayed surface and an additional layer of calcium phosphate) to ensure the proper osteointegration. The system includes an option for computer-assisted implantation surgery.
Richter et al performed the robotic-guided surgical approach on a cadaver and compared the results with those obtained using a HINTEGRA prosthesis. The authors found that the German Ankle Prosthesis had smaller effect on resulting forces and torques during partial weight-bearing passive ankle motion than the HINTEGRA prosthesis. However, to date no clinical results from patients treated with this prosthesis type are available, raising some concern regarding the interpretation of obtained data in the study by the designer.
Reference
- Richter,M., Zech,S., Westphal,R., Klimesch,Y., and Gosling,T.: Robotic cadaver testing of a new total ankle prosthesis model (German Ankle System). Foot Ankle Int, 28:1276-1286, 2007.