Cui W-Q, Won Y-Y, Baek M-H, Kim K-K, Cho J-H
Ajou University School of Medicine, Suwon City, Korea.
J Bone Joint Surg Br. 2006 Nov;88(11):1441-7. doi: 10.1302/0301-620X.88B11.17648.
The appearance of the 'grand-piano sign' on the anterior resected surface of the femur has been considered to be a marker for correct femoral rotational alignment during total knee replacement. Our study was undertaken to assess quantitatively the morphological patterns on the resected surface after anterior femoral resection with various angles of external rotation, using a computer-simulation technique. A total of 50 right distal femora with varus osteoarthritis in 50 Korean patients were scanned using computerised tomography. Computer image software was used to simulate the anterior femoral cut, which was applied at an external rotation of 0 degrees, 3 degrees and 6 degrees relative to the posterior condylar axis, and parallel to the surgical and clinical epicondylar axes in each case. The morphological patterns on the resected surface were quantified and classified as the 'grand-piano sign', 'the boot sign' and the 'butterfly sign'. The surgeon can use the analogy of these quantified sign patterns to ensure that a correct rotational alignment has been obtained intra-operatively.
股骨前侧切除面上出现的“三角钢琴征”被认为是全膝关节置换术中股骨旋转对线正确的一个标志。我们的研究旨在使用计算机模拟技术，定量评估在不同外旋角度下股骨前侧切除后切除面上的形态学模式。对50例患有膝内翻骨关节炎的韩国患者的50个右侧股骨远端进行了计算机断层扫描。使用计算机图像软件模拟股骨前侧截骨，分别相对于后髁轴以0度、3度和6度的外旋角度进行截骨，且每种情况下截骨均与手术和临床髁上轴平行。对切除面上的形态学模式进行定量并分类为“三角钢琴征”、“靴子征”和“蝴蝶征”。外科医生可以利用这些定量的体征模式类推，以确保术中获得正确的旋转对线。
