0000000000304943
AUTHOR
A. Wackerhagen
The influence of lateral release on patello-femoral joint loading in knee arthroplasty
Eight fresh, cadaveric knees have been fitted with four different total knee cemented prostheses. Loading forces at the bone implant fixation interface of the patella component have been measured in a knee joint testing rig by four miniaturized force transducers, before and after a lateral release of the patellar retinaculum. The lateral release resulted in a significant local force reduction in the lateral and/or proximal quadrant of the patella resection plane depending on the knee flexion angle, quadriceps tensile force direction, and the patellar prosthesis design.
The effect of cement fixation on initial micromotion of the femoral component in condylar knee replacement
Four fresh, cadaveric specimens were fitted with total knee replacements and mounted on a knee joint loading and measuring rig. Femoral component micromotion in the sagittal plane was measured with a transducer during flexion and extension of the specimen. Various condylar designs were used without and with cement. Movement followed a characteristic curve pattern and was less with cement fixation particularly for bone of low trabecular strength as determined by bone sample tests for stiffness. Cement fixation appears to be superior to cementless fixation.