Knee Flexion Angle Is More Important Than Guidewire Type in Preventing Posterior Femoral Cortex Blowout: A Cadaveric Study

An in Vivo 3D Computed Tomographic Analysis of Femoral Tunnel Geometry and Aperture Morphology Between Rigid and Flexible Systems in Double-Bundle Anterior Cruciate Ligament Reconstruction Using the Transportal Technique

“…Many previous studies have compared femoral tunnel length between the rigid and flexible systems, [9][10][11][12] and most reported a significantly longer femoral tunnel length from the flexible system compared with the rigid system in cadaveric studies. 9,11,12 When performing ACL reconstruction with the flexible system, we were able to change the trajectory of the guidewire because of the 42 curved guide tip.…”

“…7 Many previous studies have compared femoral tunnel length between the rigid and flexible systems, [9][10][11][12] and most reported a significantly longer femoral tunnel length using the flexible system in cadaveric studies. 9,11,12 The femoral graft-bending angle determines the bending stress of the graft and may cause graft damage and tunnel expansion caused by abrasive forces at the contact area, [13][14][15] which can be changed according to the direction of drilling and knee flexion angle. 6,16 Posterior wall breakage is one of the disadvantages of the TP technique.…”

“…7,8 The flexible system has theoretical advantages over the rigid system, including longer femoral tunnel length, further distance from the neurovascular or lateral structures of the knee, and a decreased possibility of injuring the cartilage of the medial femoral condyle. 7,[9][10][11][12] Additionally, the flexible system can be used without forcing a hyperflexed position on the knee, which allows for improved visualization over the rigid system. 7 Many previous studies have compared femoral tunnel length between the rigid and flexible systems, [9][10][11][12] and most reported a significantly longer femoral tunnel length using the flexible system in cadaveric studies.…”

“…7,[9][10][11][12] Additionally, the flexible system can be used without forcing a hyperflexed position on the knee, which allows for improved visualization over the rigid system. 7 Many previous studies have compared femoral tunnel length between the rigid and flexible systems, [9][10][11][12] and most reported a significantly longer femoral tunnel length using the flexible system in cadaveric studies. 9,11,12 The femoral graft-bending angle determines the bending stress of the graft and may cause graft damage and tunnel expansion caused by abrasive forces at the contact area, [13][14][15] which can be changed according to the direction of drilling and knee flexion angle.…”

“…There have been few studies that compare the tunnel geometry of TP techniques depending on whether they were used with the rigid system or the flexible system. [9][10][11] Furthermore, most of these studies evaluated only femoral tunnel length and the possibility of lateral structure damage using a cadaver. To our knowledge, there have been no in vivo studies that have used computed tomography (CT) to compare the crucial parameters of femoral tunnel geometry and aperture morphologic features associated with the differential postsurgical successes of the flexible and rigid systems when used with the TP technique.…”