The Effect of Valgus Deformity Degree of Knee Osteoarthritis Patients on Tibiofemoral Angle Mechanical Output and Knee Society Score After Total Knee Arthroplasty Non-Constrained at Prof. Dr. I.G.N.G Ngoerah Hospital

Background: Osteoarthritis (OA) is a progressive musculoskeletal problem causing a loss of articular cartilage and damage to cellular and biomechanical components. In Indonesia, the prevalence of OA is 36.5 million people, with 40% over 70 years old and 80% with limited movement. Malalignment in the knee joint, found in almost 10% of patients undergoing total knee arthroplasty (TKA) surgery, is a challenge for orthopedic surgeons. Factors such as body weight, high BMI, work history, malalignment, and synovitis are associated with the development of knee OA. Total Knee Arthroplasty (TKA) is a surgical procedure to overcome OA problems in the knee joint, but deformities affect the success of TKA surgery. Researchers aim to determine if there is an association between valgus deformity in knee OA patients and tibiofemoral angle correction and Knee Society Score 12 weeks after TKA. Methods: The study involved 42 patients with primary knee osteoarthritis and valgus deformity who underwent primary Total Knee Replacement (TKR) at Prof. Dr. Ngoerah Hospital. The study included patients with grade III-IV Kellgren-Lawrence knee osteoarthritis, underwent primary TKA, and had lower extremity scans before and 12 weeks postoperatively. Functional and clinical outcomes were measured using mechanical tibiofemoral angle and Knee Severity Score. Results: The study involved 21 female patients with OA Ranawat 2 and a 7:1 ratio of male and female participants. The most common OA was in the right knee. After TKR, there was no significant difference in MTFA and KSS scores between patients. However, after 12 weeks, the average MTFA score decreased to 8.57, with a significant change before and after the surgery. Keywords: Osteoarthritis, total knee arthroplasty (TKA), Kellgren-Lawrence.