2025 ISAKOS Biennial Congress ePoster
Optimizing Drilling Orientation For All Femoral Tunnel To Minimize Collision With Acl Femoral Tunnel Created By A Modified Transtibial Technique
Hyun-Soo Moon, MD, PhD, Seoul KOREA, REPUBLIC OF
Young-Jin Seo, MD, PhD, Hwaseong, Gyeonggi KOREA, REPUBLIC OF
Sung-Hwan Kim, MD, PhD, Seoul KOREA, REPUBLIC OF
Min Jung, MD, PhD, Seoul KOREA, REPUBLIC OF
Severance Hospital, Yonsei University College of Medicine, Seoul, KOREA, REPUBLIC OF
FDA Status Not Applicable
Summary
During the combined surgical procedures for ACL reconstruction using modified transtibial technique and anterolateral augmentation procedures, the optimal drill orientation of the ALL femoral tunnel was between the coronal -40° and -20° for techniques not requiring far-cortex drilling and axial 40° and coronal 10° for those requiring far-cortex drilling.
ePosters will be available shortly before Congress
Abstract
Introduction
This study aimed (1) to compare the three-dimensional (3D) geometric characteristics of the femoral tunnels created by the transportal technique (TP) and the modified transtibial technique (MTT) in anterior cruciate ligament (ACL) reconstruction, and (2) to analyze the optimal drill orientation to minimize the risk of tunnel collision and reduce damage to surrounding structures during combined ACL reconstruction with MTT and anterolateral augmentation procedures, considering the need for far-cortex drilling (FCD).
Methods
The 3D-reconstructed femoral models of patients who underwent ACL reconstruction with MTT between 2015 and 2018 were utilized. The geometric factors of the femoral models made with MTT were compared with those created with TP in a previous study. Virtual ALL femoral tunnels were simulated to evaluate 45 drilling combinations. Subsequently, the violation of the femoral cortex by the ALL femoral tunnels and their trajectories, as well as the minimum distance between the ACL and ALL femoral tunnels, were assessed.
Results
A total of 27 subjects were included in the analysis. Significant differences in geometric factors related to the ACL femoral tunnel, including tunnel position, tunnel length, and inclination angles of the ACL in each plane, were observed between the MTT and TP. For techniques not requiring FCD, the optimal drill orientation for the ALL femoral tunnel was between the coronal -40° and -20°, which resulted in no cortex violation by the ALL tunnel and eliminated the risk of tunnel collisions (9.0 ± 4.1mm; collision rate 0%). Simultaneously considering the trajectory of the ALL tunnel, which represents FCD, the optimal drill orientation was determined to be axial 40° and coronal 10°, resulting in the longest minimal distance between tunnels without the risk of femoral cortex violation (4.9 ± 3.5mm; collision rate 7.4%).
Conclusion
The ACL femoral tunnel created with MTT exhibited distinct geometric characteristics compared to those found in the TP. During the combined surgical procedures for ACL reconstruction using MTT and anterolateral augmentation procedures, the optimal drill orientation of the ALL femoral tunnel was between the coronal -40° and -20° for techniques not requiring FCD and axial 40° and coronal 10° for those requiring FCD.