The four-axis polycentric knee joint T222.2 has been specially designed for use in amputation with erosion in the knee joint and with long thigh stumps. The bottom adapter has a spring element supporting the built-in extender, which enables a smooth extension phase. By tightening or loosening the front screw, it is possible to adjust the bending and extension phase. In the upper part built-in metal component T213.2 for direct lamination with a thigh prosthetic socket. In the case where gel cartridges are used, the T241 pyramid adapter can be installed. The special design of the articulated joint on rolling bearings enables smooth adjustment and control of the extension phase. The articulated joint has a special design that significantly extends the service life. Design reserved in Patent Office.