ISO 14243-5 Durability Performance of the Patellofemoral Joint
Durability of the patellar and femoral components are tested through joint wear simulation that follows a squatting sub-cycle and two low flexion sub-cycles. Loading and displacement waveforms are applied for 50,000 cycles or until patellofemoral joint failure occurs in the form of delamination, cracking or other mechanical failure. It is recommended to test the largest femur with the smallest patella to achieve the highest contact stress and subsurface shear for worst-case conditions.