After artificial knee replacement, several reasons may necessitate the substitution of individual implants or the entire artificial joint. This is referred to as a revision or exchange operation.
Causes that require a revision include loosening of the prosthesis (e.g. in case of severe osteoporosis), infections, wear of the polyethylene inlay or other components, but also injuries involving the artificial joint (e.g. falls).
The exchange of a knee prosthesis is often more difficult than the primary implantation. Typical of exchange implants are the long stems on the femoral and tibial components. They serve to stabilise the knee in the longitudinal axis and prevent shifting of the thigh and shank bones.
It is important to recognise early when a revision becomes necessary. An excessive delay or late recognition may negatively affect the bone situation and, in the worst case, make the implantation of a revision prosthesis impossible. Regular exams by the orthopaedist minimise this risk.