Background: Precise measurement of lateral femoral bowing is important to achieve postoperative lower limb\nalignment. We aimed to investigate factors that affect the precision of the radiographic lateral femoral bowing\n(RLFB) angle using three-dimensional (3D) models and whether the angle affects surgery design.\nMethods: Forty femurs in total were divided into two groups based on their preoperative RLFB angle. The flexion\ncontracture angle, preoperative and postoperative RLFB angles, and intersection angle between the mechanical and\nanatomical axes were compared. The angle between the arc and sagittal planes, varus and valgus angles, and\nintersection angle between the mechanical and anatomical axes were measured on a 3D model.\nResults: There was no significant between-group difference in 3D model measurements of the angle between the\narc and sagittal planes (p = 0.327). There was no significant difference between the mechanical and anatomical axes\nmeasured by both imaging modalities (p > 0.258). When the RLFB was >5�°, the flexion contracture angle and\nradiographic femoral bowing angle were positively correlated (r = 0.535, p < 0.05). Distal femur varus and valgus\nangles significantly differed between the two groups (p = 0.01). After total knee arthroplasty, the radiographic\nfemoral bowing angle decreased significantly. When the casesâ�� radiographic femoral bowing angle is larger and the\nangle between the arc and sagittal planes is smaller as measured in 3D models, the angle between the arc and\ncoronal planes is larger.\nConclusion: The radiographic femoral bowing angle does not reflect the actual size of lateral femoral bowing, does\nnot greatly affect surgery design, and is greatly affected by flexion contracture deformity. A RLFB angle larger than\n15�° indicates real lateral femoral bowing.
Loading....