Clinical results and influence of patellofemoral joint design on the stability of the patellar component in Miller-Galante types I and II, and Nexgen total knee arthroplasty

We report here on the long-term outcome of Miller-Galante (MG) I-type total knee arthroplasty (TKA) as well as the short-term outcomes of MGII hydroxyapatite (HA)-type TKA using cobalt-chrome (CoCr) fiber-metal coated with hydroxyapatite tricalcium phosphate and Nexgen-type TKA. We also describe the characteristics and drawbacks of these artificial joints, and report on the degree of stability of the patellar component as evaluated on skyline-vie iv radiographs of the knee. In MGI, use of the metal-backed patellar component resulted in failure in 24% of cases. However, long-term follow-up (12 years) after surgery revealed that the cementless fixation using fiber-metal of titanium alloy provided good stability, without the development of aseptic loosening. Postoperative follow-up for 3 to 4 years after MGII-HA type TKA proved the usefulness of the materials used for the cementless fixation, and no radiolucent line was observed on radiographs. The skyline view radiographs indicated that the stability of the patellar component provided by MGII-HA and Nexgen is superior to that provided by MGI.