What is the definition or description of: partial knee replacement?

Partial knee : Replacing one of the 3 compartments in the knee...Medial, lateral or patellofemoral.

Partial knee: Partial knee replacement is a procedure that removes and substitutes damaged knee tissue from 1 or 2 of the 3 knee compartments: medial, lateral, & patellofemoral. Some native joint surface remains.

Uni-knee: The knee joint can be divided anatomically into three "compartments"- medial (inner half), lateral (outer half), and patello-femoral (patella or kneecap). If a patient develops non-inflammatory (e.g. Osteoarthritis) arthritis in just one of these three compartments, they may be a candidate for a partial knee replacement, in which just one "compartment" is replaced., instead of a total knee.