What is Total Knee Replacement Surgery?
In knee replacement surgery, a damaged knee is replaced with an "artificial knee joint". The worn ends of the bones are replaced with metal and plastic parts. Such a prosthesis is necessary when the articular cartilage has becomes so severely damaged or worn away that levels of pain and discomfort in the knee are high and the knee joint ceases to function properly i.e. where there is a reduction in the range of motion in the joint, or in cases where the knee joint has become malpositioned.
It is of particular importance in knee replacement surgery, that the thigh is correctly connected to the lower leg. Mobile-bearing designs (rotating platform) in total knee arthroplasty (TKA) implant systems are recommended. In these so-called "mobile bearings", meniscal bearings which replicate the natural structure of the knee, are used as part of the knee replacement.
At the Gelenk Klinik "surface replacement arthroplasty" is used almost exclusively. This is where the bone ends of the thigh and lower leg are replaced without mechanically connecting the new components, this is because in instances where connections have been used, these have been known to fail over time, often breaking due to material fatigue.
The stability of the type of implant used, very much depends on the viability of the still intact knee joint capsule. If one waits too long before undergoing knee surgery, the capsular ligaments become so unstable that a fixed bearing remains the only option.
Ideally, the collateral and posterior cruciate ligaments are retained in order to obtain a natural and stable sequence of movements).
When the collateral ligaments are considerably blocked, for instance due to valgus (bow leggedness) or varus malalignment (knock-knees), it is necessary to use a mechanically coupled type of implant, where long shafts are introduced into the tibia and femur.