 Replacement of the trapezo-metacarpal joint with prosthetic material is also proposed and has the advantage to avoid the reduction of the thumb column. Several models are available, mono or bipolar, with a conical or hemispherical cup. Another option is the placement of implants. They were first used when a partial trapeziectomy was possible to counter the collapse of the column and are made of different materials such as metal, silicone, ceramic, pyrocarbon , and gelfoam. 