A structure improvement of orthopaedic implant for connecting a distal femur and a proximal tibia, and a stem was implanted into the proximal tibia, inwhich formed to allow inter-engagement between the stem of the tibia and the structure improvement of orthopaedic implant. The structure improvement of orthopaedic implant includes a tibial baseplate, a tibial insert, and a reinforcement. The tibial baseplate forms a recess having a bottom that has a central portion defining a through hole extending through the tibial baseplate. The tibial insert includes a support, a through region, and a projection, wherein an end of the tibial insert forming the projection corresponding to the recess of the tibial baseplate for press-fitting to the tibial baseplate. The reinforcement is inset in the tibial insert and includes a sleeve and a bolt. As such, the advantages of stable coupling includes force resistance, avoids insert loosening then extends prosthetic longevity.
