Correlation between Femoral Tunnel Location in Three-Dimensional Computed Tomography and Femoral Tunnel Angle in Plain Radiographs after Single-Bundle Anterior Cruciate Reconstruction / 대한정형외과학회잡지

ABSTRACT

PURPOSE: The purpose of this study is to determine correlation between femoral tunnel angle in the coronal plane on a simple radiograph and femoral tunnel location in the sagittal plane on three-dimensional computed tomography (3D-CT). MATERIALS AND METHODS: The subjects included 42 patients who underwent 3D-CT after the operation out of 70 cases of anterior cruciate ligament reconstruction using quadriceps tendon-patelllar bone autograft from April, 2009 to June, 2011. Measurement of the femoral tunnel angle was based on the anatomical axis of the femur in antero-posterior (AP) and Rosenberg views; femoral tunnel location was described as a proportional percentage on the medial surface of the lateral femoral condyle in the 3D-CT image; then the correlation between femoral tunnel angle and femoral tunnel location was analyzed retrospectively. RESULTS: Femoral tunnel angle was 41.5degrees+/-6.8degrees (range 29.7degrees-53.9degrees) on AP radiographs, and 34.9degrees+/-6.9degrees (range 23.8degrees-46.5degrees) on Rosenberg views. The femoral tunnel was located 36.9%+/-11.3% from posterior, and 38.1%+/-6.5% from proximal on the 3D-CT image. On plain AP radiographs, femoral tunnel angle and femoral tunnel location showed negative correlation (p<0.001, rho=-0.498), and, in comparison with Rosenberg view, they showed negative correlation (p=0.006, rho=-0.416). Twenty three patients (53.5%) had femoral tunnel in the anatomical location. Their femoral tunnel angle on AP radiographs was 43.3degrees+/-6.1degrees, while the femoral tunnel angle of patients who had femoral tunnel in non-anatomical locations was 38.4degrees+/-6.4degrees (p=0.004). In the Rosenberg picture, similar difference was observed between the two groups (p=0.012). CONCLUSION: On AP radiographs and Rosenberg views, femoral tunnel angle showed significant correlation with the femoral tunnel location on the 3D-CT image, and the group who had femoral tunnel location in the anatomical range showed a relatively higher femoral tunnel angle.