“…There is no bone ingrowth in the distal femur, resulting in the inability to resist rotation under the S-ROM sleeve, which causes small movement between the prosthesis and the femur. Eventually, osteolysis, resorption, and loosening of the prosthesis occur at the osteotomy site ( 23 ). This is the primary cause of postoperative loosening, with secondary reasons including: (1) Due to osteotomy, bone union is absent or inadequate.…”