For patients who suffer from arthritis that is isolated to one area (or compartment) of the knee, partial (or unicondylar) knee replacement (UKA) may be an alternative to total knee replacement (TKA). In this operation, only the affected area of the knee, usually the inside (medial) portion, is replaced by an artificial surface and the remainder of the joint surface of the knee is retained. There are advantages and disadvantages to UKA in comparison to TKA; the advantages are a very minimally invasive technique (2- to 3-inch incision) with a generally quicker (1- to 2-day hospital stay) and less painful recovery, a more 'normal' feeling and moving knee, and an easier transition to a revision arthroplasty (a replacement of the replacement) should that become necessary. The disadvantages are a higher early failure rate from loosening of the artificial joint from the bone (about 5% instead of about 1%) and the possibilty of progression of arthritis in other areas of the knee that may lead to a need for conversion to a TKA. The surgeons at MaineOrtho are trained and experienced in the use of the Oxford partial-knee system, which is the only mobile-bearing UKA available and has an excellent clinical track record. Your surgeon will happily answer your questions as to whether you are a candidate for a UKA to address your painful knee arthritis.
To see an example of a partial knee replacement, click here