Purpose: The first purpose of this study was to examine whether fluoroscopic-based navigation system contributes to the accuracy and reproducibility of the bone tunnel placements in single-bundle anterior cruciate ligament (ACL) reconstruction. The second purpose was to investigate the application of the navigation system for double-bundle ACL reconstruction.
Methods: A hospital-based case-control study was conducted, including a consecutive series of 55 patients. In 37 patients who received single-bundle ACL reconstruction, surgeries were performed with this system for 19 knees (group 1) and without this system for 18 knees (group 2). The positioning of the femoral and tibial tunnels was evaluated by plain sagittal radiographs. In 18 patients who received double-bundle ACL reconstruction using the navigation system (group 3), the bone tunnel positions were assessed by three-dimensional computed tomography (3D-CT). Clinical assessment of all patients was followed with the use of Lysholm Knees Score and IKDC.
Results: Taking 0% as the anterior and 100% as the posterior extent, the femoral tunnels were 74.9 ± 3.0% in group 1 and 71.5 ± 5.8% in group 2 along Blumensaat's line, and the tibial tunnels were 42.3 ± 1.4% in group 1 and 42.5 ± 4.6% in group 2 along the tibia plateau. The bone tunnel positions in group 1 were located significantly closer to the position planned preoperatively and varied less in both femur and tibial side, compared with those without navigation (group 2). (Femur: P < 0.05, Tibia: P < 0.001) 3D-CT evaluation of double-bundle ACL reconstruction (group 3) also demonstrated that the bone tunnel positions of both anteromedial (AM) and posterolateral (PL) were placed as we expected.
Conclusion: The fluoroscopic-based navigation system contributed to the more reproducible placement of the bone tunnel during single-bundle ACL reconstruction compared with conventional technique. Additionally, this device was also useful for double-bundle ACL reconstruction.
Level of evidence: Case-control study, Therapeutic study, Level III.