Treatment group

Patients in the treatment group received artificial TKA. The specific operation was as follows: Under general anesthesia, the patients were placed in a supine position, and an airbag tourniquet was used to pressurize the blood. The medial approach of the iliac crest was applied. First, routine femoral condyle and tibia plateau osteotomies were performed. Then, the posterior lateral joint capsule and lateral iliotibial band were completely loosened by using a pie-crusting technique. The standard was set to the outer compartment tension, and the rectangular spacer with appropriate thickness was placed in the knee joint extension gap. If the knee joint was still unstable under valgus stress after the rectangular straightening gap and the accurate lower limb force line were obtained, the starting point was set in the medial collateral ligament, and the osteotomy was upwardly slid, thereby tightening the medial collateral ligament.