A quantitative technique to create a femoral tunnel at the averaged center of the anteromedial bundle attachment in anatomic double-bundle anterior cruciate ligament reconstruction

Abstract

BackgroundIn the anatomic double-bundle ACL reconstruction, 2 femoral tunnel positions are particularly critical to obtain better clinical results. Recently, a few studies have reported quantitative identification methods for posterolateral (PL) bundle reconstruction. Concerning anteromedial (AM) bundle reconstruction, however, no quantitative clinically available methods to insert a guide wire at the center of the direct attachment of the AM mid-substance fibers have been reported to date.MethodsFirst, we determined the center of the femoral attachment of the AM mid-substance fibers using 38 fresh frozen cadaveric knees. Based on this anatomical sub-study, we developed a quantitative clinical technique to insert a guide wire at the averaged center for anatomic double-bundle ACL reconstruction. In the second clinical sub-study with 63 patients who underwent anatomic ACL reconstruction with this quantitative technique, we determined the center of an actually created AM tunnel. Then, we compared the results of the second sub-study with those of the first sub-study to validate the accuracy of the quantitative technique. In both the sub-studies, we determined the center of the anatomical attachment and the tunnel outlet using the “3-dimensional clock” system. The tunnel outlet was evaluated using the “transparent” 3-dimensional computed tomography.ResultsThe averaged center of the direct attachment of the AM bundle midsubstance fibers was located on the cylindrical surface of the femoral intercondylar notch at “10:37” (or “1:23”) o’clock orientation in the distal view and at 5.0-mm from the proximal outlet of the intercondylar notch (POIN) in the lateral view. The AM tunnel actually created in ACL reconstruction was located at “10:41” (or “1:19”) o’clock orientation in the average and at 5.0-mm from the POIN. There was no significant difference between the 2 center locations.ConclusionsThe quantitative technique enabled us to easily create the femoral AM tunnel at the averaged center of the direct attachment of the AM bundle midsubstance fibers with high accuracy. This study reported information on the geometric location of the femoral attachment of the AM bundle and a clinically useful technique for its anatomical reconstruction.

3D computer tomography for measurement of femoral position in acl reconstruction

“… 14 It was originally described for radiographies, but is also utilized in 3D CT scan evaluation. 2 , 10 , 11 , 14 , 15 In rendered and cropped 3D CT scans, high levels of intra- and inter-observer reliability were demonstrated 14 , 15 , 17 for this quadrant method technique, as the present study demonstrated.…”

“…The same simulated central ACL position was loaded in the transparent sagittal view, as described before, and the quadrant method of Bernard et al 12 was applied in the picture obtained, as described by Lertwanich et al 15 and Kai et al 10 In 3D CT scans. A line connecting the most anterior and posterior edge of the intercondylar roof was the reference for Blumensaat line.…”

Effects of Remnant Tissue Preservation on Clinical and Arthroscopic Results After Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction

“…We determined an appropriate guide wire location using the previously reported fluoroscopic method. 23,48 After the guide wire was inserted, a femoral tunnel was gently drilled by use of a cannulated drill, penetrating the remnant tissue.…”

Is the Grafted Tendon Shifted Anteriorly in the Femoral Tunnel at the Postremodeling Phase After Anterior Cruciate Ligament Reconstruction? A Clinical MRI Study

“…The details of the anatomic procedure have been previously described ( Figure 2 ). 14 , 37 , 38 In the double-bundle procedure, the AM graft diameter ranged from 6 to 6.5 mm (mean ± SD, 6.3 ± 0.3 mm), and the PL graft diameter ranged from 5.5 to 6 mm (mean ± SD, 5.8 ± 0.2 mm).…”