The patella in total knee replacement: does it matter? 750 LCS total knee replacements without resurfacing of the patella.

Abstract

Hingelike moving total knee replacement (TKR) has shown that the "rotating" function of the quadriceps muscle becomes lost. Dynamic work of the vastus medialis is no longer needed, and the static part of the quadriceps muscle assumes the major part of the work, beginning with continuously dislocating the patella to the lateral side. We operated on 436 knees using the LCS (De Puy Orthopaedics, Warsaw, IN) meniscal bearing TKR. No primary patellar resurfacing was necessary in this series. The New Jersey Score increased constantly over the 5-year follow-up from 83 after 2 years to 90 after 5 years. This shows that there is no deterioration which can be attributed to a deterioration in the patellar behavior. Nonresurfacing of the patella is a possible solution if the kinematics of the TKR allow physiological rotation, the prosthesis is built anatomically, the alignment is correct, the anatomy of decelerator/extensor mechanism is respected by the approach, and ligamentous stability is good.