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INTRODUCTION The tibial cut referenced to the center of the intercondylar eminence (IE) in total knee arthroplasty (TKA) often leads to malalignment of the knee due to preexisting tibial deformities, is liable to polyethylene (PE) wear subsequently causing implant loosening and malalignment, which has been a common cause of knee arthroplasty revisions. Our case showed that careful preoperative planning gives good component placement and better correction of the mechanical axis of the leg, therefore increases the survivorship of the TKA. CASE PRESENTATION A 62 years old male present with bilateral knee pain (right>left), worsened by walking and squatting. Plain radiograph showed advanced knee Osteoarthritis (OA) (right>left) with significant -S-shaped- tibia valgus angle of 5.11° and 4.37° respectively. METHOD The patient had preoperative full-length (long film) standing bilateral lower limb radiographs with the patella facing forward. To measure the Tibial bowing angle and tibial reference point we use a modified method described by Thippana et al, using PACS software. From the preoperative radiographs, shifting to the medial of center intercondylar reference point of the proximal tibia was determined. The distance between the center of the intercondylar eminence and the medial condyle reference point was calculated. The same reference point was replicated intraoperatively. Post-operatively, the same radiographs were obtained at 4-weeks follow-up, medial proximal tibial component angle (MPTA) and hip knee ankle (HKA) angle were assessed. RESULTS Postoperative radiograph showing MPTA/HKA; 88.62°/180.75° of the right knee (A) and 89.69°/182.89° of the left knee (B) with the use of the medial tibial condylar reference point in a patient with tibia valgus. Both nearly achieving the optimal MPTA of 90° + 3° and HKA of 180° + 3° DISCUSSION Distributing load between tibial plateau could increase the PE survival rate and maintain the desired knee alignment in TKA, which could be achieved by preoperative measurements. Studies showed that >5° malalignment increased implant thickness loss by 0.11 mm per year in the concavity of the deformation, which increase chance of malalignment and the needs of TKA revisions. We recommend that the degree of reference point shift should be individualized based on the deformity on preoperative full-length radiographs. CONCLUSION Preoperative measurement of tibial bowing angle and tibial reference point using modified Thippana method is necessary to achieved the desired reference point for extramedullary tibial cutting jig in knees with significant tibia valgus.