Every surgery requires special instruments.
For this procedure, a special implant, or artificial joint, is used to replace your knee. The thigh and shinbone parts of the implant will look something like this. The implants are made of metal, normally an alloy, which is a combination of several metals.
Most implant designs use a small, specialized plastic insert between the two metal parts, to act as a weight-bearing surface for the joint, much like your natural cartilage. It will look something like this.
Depending on the type of implant used, bone cement may be used to fix the implant components securely into place.