Chevrot A, Hazebroucq V, Vallée C, Godefroy D, Wybier M, Codert E, Gires F
Service de Radiologie B, Hôpital Cochin, Paris.
Rev Chir Orthop Reparatrice Appar Mot. 1991;77(5):370-3.
A wrong patient's position on the CT scan table may lead to mistakes in the measurement of femoral neck anteversion. We present an experimental demonstration using a wood manufactured femur model. If the slices are performed with flexion of the thigh, the measurement is lower than the true value. Thus, to check the measurement on the picture of added slices, it is necessary to have a superimposition of the pictures of the upper part and the lower part of the femur. Otherwise, the measure is wrong and the mistake depends of the direction of the shifting: --if the lower part of the femur is higher, the anteversion measure is lower than expected. --if the lower part of the femur is lower, the anteversion measure is higher.
患者在CT扫描台上的位置错误可能会导致股骨颈前倾角测量出现误差。我们用木制股骨模型进行了实验演示。如果在大腿屈曲状态下进行切片，测量值会低于真实值。因此，为了在叠加切片图像上检查测量结果，有必要使股骨上部和下部的图像相互叠加。否则，测量结果就是错误的，误差取决于移位方向：——如果股骨下部位置较高，前倾角测量值会低于预期。——如果股骨下部位置较低，前倾角测量值会较高。
