Li Y, Gao YH, Ding L, et al. - Fifty-five osteoarthritis tibias with > 10° varus preoperatively were randomized into valgus, neutral, and varus groups on the basis of their postoperative alignment deviation by the experts in order to assess proximal and distal tibial torsion using 3D computed technology to ascertain a new assessment method, as well as to examine the correlation between tibial torsion and postoperative alignment deviation. According to the new method, proximal tibial torsion was smaller and distal torsion was greater in the valgus group vs other two groups. No notable variation was obtained when contrasting these torsions by the traditional method. The postoperative alignment deviation grew following simulated osteotomy guided by the intramedullary system in the valgus group, while no vital betterment was discovered in the varus group. Hence, valgus deviation in knee arthroplasty was recognized as the main cause for knees in which the proximal tibial internal torsion was too small and the distal external torsion was too great, according to this new tibial-rotation evaluation method. The use of an intramedullary system may aid in decreasing this deviation.