Wall Of Lateral Femoral Condyle Research Articles

How anatomical is our tunnel? A three dimensional CT evaluation of femoral tunnel in anatomic anteromedial single bundle anterior cruciate ligament reconstruction

<p class="abstract"><strong>Background:</strong> ACL reconstruction has become a common orthopaedic procedure. The anatomy and biomechanics of ACL have been one of the most researched and debated topics in the orthopaedic literature. This has implication on the surgical procedure too with shift from traditional transtibial to more anatomic anteromedial ACL reconstruction. Anteromedial technique results in more anatomic femoral tunnel with graft positioned at the native insertion site. The tunnel position is crucial for better outcome after ACL reconstruction. The purpose of the study was to ascertain the femoral tunnel position made by anatomic single bundle reconstruction with the help of three dimensional computer tomography.</p><p class="abstract"><strong>Methods:</strong> A prospective case series involving thirty patients with ACL tear who underwent anteromedial single bundle ACL reconstruction. Computer tomography scans were performed on thirty knees that underwent single bundle anteromedial ACL reconstruction. Three dimensional models were created and the data was analyzed according to coordinate system method. Femoral tunnel position was measured in proximal to distal and posterior to anterior directions. This data was compared with the already published reference data on anatomical tunnel position.<strong></strong></p><p class="abstract"><strong>Results:</strong> Femoral tunnel centre on the medial wall of lateral femoral condyle was located at 35±9% in the posterior to anterior direction. In the proximal to distal direction, the tunnel was placed at 30±12%. Femoral tunnel was placed anteriorly as compared to anatomic anteromedial and posterolateral tunnel position. There was no significant difference in tunnel position in proximal to distal direction.</p><p class="abstract"><strong>Conclusions:</strong> Femoral tunnel centre on the medial wall of lateral femoral condyle was located at 35±9% in the posterior to anterior direction. In the proximal to distal direction, the tunnel was placed at 30±12%. Femoral tunnel was placed anteriorly as compared to anatomic anteromedial and posterolateral tunnel position. There was no significant difference in tunnel position in proximal to distal direction.</p>

Study of bony morphometry of femoral ACL footprints using 3D CT in normal knees in Indian patients

Background: With the identification of two separate bundles of ACL and growing interest in double bundle anatomic reconstruction, characterization of insertion site anatomy of ACL has received attention. To give the better clinical results, it is desirable that the ACL is reconstructed to its anatomical insertion site as much possible. The purpose of the study is to evaluate the bony morphometry of femoral ACL footprints using 3 dimensional CT in normal knees of Indian patients. Material and method: Total of 20 patients were included in the study & CT scans of their normal knees were done using 3D CT scan. All the CT scans were individually reported randomly by two senior radiologists separately twice by each at an interval of minimum three weeks. Impression of femoral footprint of ACL was demarcated on volume rendered images. The anatomical position of centres of anteromedial (AM) & posterolateral (PL) bundles was measured by coordinate axis method. Results: On the medial wall of lateral femoral condyle in the anatomic posterior to anterior direction, the centres of AM &PL bundles of ACL were located at a mean of 26.9 ± 4.2 % and 16.9 ± 3.6 % respectively. The proximal to distal locations of centres of the AM & PL bundle were 22.5 ±2 % and 49.8± 6.2 % respectively. The interobserver and intraobserver reliability of 3D CT scan in assessment of femoral footprint anatomy was excellent. Conclusion: Our study demonstrates that 3D CT is a useful tool to evaluate the femoral footprints anatomy of ACL bundles. The results of our study seem to be in tune with the published cadaveric studies from western world and found no significant difference in the bony morphometry of ACL footprint from the western world. The study may be considered as the landmark for future studies of anatomic ACL reconstructions.

Avoiding Posterior Cruciate Ligament and Roof Impingement With Transtibial Anterior Cruciate Ligament Reconstruction: Keys to Correct Tunnel Placement

Summary: Avoiding posterior cruciate ligament (PCL) impingement, avoiding roof impingement, and replicating the tension pattern of the intact anterior cruciate ligament (ACL) are the keys to successful ACL reconstruction. To avoid PCL impingement, the tibial tunnel should be placed in the coronal plane at an angle between 60° and 65° with the medial joint line, and the lateral edge of the tibial tunnel should pass through the apex of the lateral tibial spine. Placement of the tibial tunnel with these 2 criteria usually requires removal of the medial wall of lateral femoral condyle (ie, wallplasty) until the space between the PCL and lateral femoral condyle exceeds the diameter of the graft by 1 mm. The guidewire should be drilled through the lateral hole in the bullet of the guide and enter the notch midway between the PCL and lateral femoral condyle. To avoid roof impingement without a roofplasty, the tibial tunnel should be customized in the sagittal plane 5 to 6 mm posterior and parallel to the intercondylar roof with the knee in maximum hyperextension, which accounts for variability in roof angle and knee extension. We prefer to use the Howell 65 Degree Tibial Guide to place the tibial tunnel with these criteria in the coronal and the sagittal planes. When the femoral tunnel is drilled through and in line with the correctly placed tibial tunnel, and when the back wall of the femoral tunnel is 1 mm thick, the tension pattern in the graft replicates that of the intact ACL.