Intervention
arthritis
OSTEOPHYTES, ARTHRITIS
A single experienced surgeon performed all surgeries. The implanted prosthesis was the K-MOD medial pivot implant system (Gruppo Bioimpianti, Italy). A tourniquet was used during the procedure. The operation was always performed first on the right side, regardless of the severity of arthritis, through a standard medial parapatellar approach. A tibial cut was made perpendicular to the mechanical axis using an extramedullary alignment guide. The tibial posterior slope was adjusted based on preoperative X-ray (ranged 3–7°), as anatomically precise as possible, to achieve the appropriate tension of the PCL and balancing of the flexion gap. A distal femoral cut was made in 5° of valgus using an intramedullary femoral alignment guide, and the extension gap was measured using spacer blocks. Femoral rotation and the posterior femoral condyle cut were determined using a hybrid method, a combination of the measured resection technique and gap-balancing technique, and the flexion gap was measured using spacer blocks. The posterior femoral osteophytes were excised. Subsequently, trial implants were inserted to assess the joint space; varus and valgus stability, patellar tracking, and ROM were measured; and the pull-out lift-off test[