Variations in sagittal locations of anterior cruciate ligament tibial footprints and their association with radiographic landmarks: a human cadaveric study

Abstract

BackgroundThis cadaveric study aimed to demonstrate variation of the anterior cruciate ligament (ACL) tibial attachment in the sagittal plane, and to analyze the radiographic landmarks which predict the sagittal location of the ACL tibial attachment.MethodsIn 20 cadaveric knees, native ACLs were removed and the centers of the ACL tibial and femoral attachments were marked with metal pins. Full extension lateral radiographs were then obtained in each cadaveric knee. Using the full extension lateral radiographs, the sagittal location of the ACL tibial footprint center was estimated as a percentage in the Amis and Jakob’s line. Several radiographic landmarks including the geometry of Blumensaat’s line and the apex of the tibial eminence were measured. Then, the relationship between the variation of the sagittal location of the ACL tibial footprint and several radiographic landmarks were analyzed using Pearson’s correlation analysis.ResultsThe average sagittal position of the native ACL tibial footprint was 40.9% (range: 38.0–45.0%). The line connecting the centers of the ACL footprint was nearly parallel to Blumensaat’s line, with an average angle of 1.7° (range: 0–4.1°). In addition, the distance from the point where Blumensaat’s line meets the tibial articular surface to the center of the ACL tibial footprint was almost consistent, at 7.6 mm on average (range: 6.4–8.7 mm). The correlation analysis revealed that the geometry of Blumensaat’s line was significantly correlated with the sagittal location of the ACL tibial footprint.ConclusionThe radiographic landmark that showed a significant correlation with the ACL tibial footprint in the full extension lateral radiographs was Blumensaat’s line.

Assessment of Anterior Cruciate Ligament Tibial Footprint Sagittal Diameter and Orientation of the Ligament in the Intercondylar Notch in Indian Population: A Magnetic Resonance Imaging (MRI) Analysis

“…Our study revealed the tibial footprint to be about 43.51% ± 3.1 from the anterior tibial cortex along the Staubli and Rauschning line. It is in accordance with the previous studies ( Table 2) and was noted to be more than 40% as per Cho et al study in the East Asian population [14]. It would be advisable to keep the center of the tibial tunnel during single bundle reconstruction between the range 37.31% and 49.71% (mean ± 2SD) as it would help in preventing a very anterior or posteriorly placed graft.…”

Tibial Tunnel Placement in ACL Reconstruction Using a Novel Grid and Biplanar Stereoradiographic Imaging

“…6,8,12,34 Other methods have considered the tibial slope and used the tibial articular surface to describe a given position with a percentage along the AP depth. 6 For the mediolateral (ML) placement on an AP radiograph, few studies have described the optimal location of tunnel placement. 20,27,34 EOS is a biplanar stereoradiographic imaging modality (Figure 1) (EOS imaging, Paris, France).…”

“… 32 Multiple reconstruction techniques target an anatomic placement of the tibial and femoral tunnels. 3 , 6 , 19 , 23 , 25 , 31 , 34 , 35 Tibial tunnels placed too far anteriorly may lead to increased graft obliquity and subsequent impingement, whereas grafts placed too far posteriorly may lead to increased anterior translational laxity. 2 , 3 , 6 , 12 , 20 , 28 Several studies have used 3-dimensional (3D) computed tomography (CT) scans to examine anatomic landmarks and to guide intraoperative tibial tunnel placement.…”

“… 3 , 6 , 19 , 23 , 25 , 31 , 34 , 35 Tibial tunnels placed too far anteriorly may lead to increased graft obliquity and subsequent impingement, whereas grafts placed too far posteriorly may lead to increased anterior translational laxity. 2 , 3 , 6 , 12 , 20 , 28 Several studies have used 3-dimensional (3D) computed tomography (CT) scans to examine anatomic landmarks and to guide intraoperative tibial tunnel placement. 31 , 32 , 35 Other studies have focused on image-guided techniques, such as radiographs and CT scans, to evaluate tunnel placement on the tibial and femoral surfaces.…”

“…For the anteroposterior (AP) direction, Amis and Jakob 2 were the original authors to popularize the placement as a percentage along a line of reference extending from the anterior portion of the proximal tibia to the most posterior portion, while being parallel to the tibial plateau. 6 , 8 , 12 , 34 Other methods have considered the tibial slope and used the tibial articular surface to describe a given position with a percentage along the AP depth. 6 For the mediolateral (ML) placement on an AP radiograph, few studies have described the optimal location of tunnel placement.…”