Reliability in Full Leg Standing Radiographs for Total Knee Arthroplasty Pre-Operative Planning

One of the most common modes of failure for total knee arthroplasty is aeseptic loosening of the components [2]. Aeseptic loosening failure of both the femoral and tibial components has been shown to occur if the alignment of the knee occurs outside of ± 3° from the mechanical alignment in the coronal plane [3]. Proper mechanical alignment of the knee is dependent on the correct proximal varus/valgus tibia resection that is calculated from FLS radiographs. This study compares measurements made for tibial varus/valgus alignment from FLS radiographs to measurements made from anterior-posterior radiographs of just the tibia in an effort to show that FLS studies are accurate and robust enough, despite rotation that can be introduced due to the patient’s full leg deformity, to be used to correctly account for tibia bows in pre-operative planning for total knee arthroplasty.