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Different femoral tunnel placement in posterior cruciate ligament reconstruction: a finite element analysis
BMC Musculoskeletal Disorders volume 24, Article number: 93 (2023)
At present, there is no consensus on the optimal biomechanical method for Posterior cruciate ligament (PCL) reconstruction, and the “critical corner” that is produced by the femoral tunnel is currently considered to be one of the main reasons for PCL failure. Thus, the purpose of this study was to identify one or several different tunnels of the femur, thereby reducing the influence of the "critical corner" without reducing the posterior stability of the knee.
CT and MRI data of the knee joint of a healthy adult man were collected, and computer-related software was used to reconstruct the finite element model of the knee joint, to provide different properties to different materials and to allow for the performance of a finite element analysis of the reconstructed model. The position of the femoral tunnel was positioned and partitioned according to anatomical posture, and three areas were divided (the antero-proximal region, the antero-distal region and the posterior region). In addition, we applied a posterior tibial load of 134 N to the reconstructed model, recorded and compared different tunnels of the femur, conducted peak stress at the flexion of the knee joint of 0°, 30°, 60° and 90°, and elicited the displacement of the proximal tibia.
Among the 20 different femoral tunnels, the graft peak stress was lower in tunnels 4, 12 and 18 than in the PCL anatomical footpath tunnel 13, especially at high flexion angles (60° and 90°). These three tunnels did not increase the posterior displacement of the proximal tibia compared with the anatomical footpath tunnel 13.
In summary, among the options for PCL reconstruction of the femoral tunnel, the tunnels located 5 mm distal to the footprint and 5 mm anterior to the footprint could reduce the peak stress of the graft; additionally, it may reduce the "critical corner" and was shown to not reduce the posterior stability of the knee joint.
Posterior cruciate ligament (PCL) injury is a common clinical problem. PCL tears comprise 3% of outpatient knee injuries and 38% of acute traumatic knee hemarthroses . Some scholars believe that isolated injuries account for about 40% of PCL injuries . Patients with isolated grade I or II PCL injury, or grade III injury with mild symptoms or low activity needs are treated nonoperatively and typically have good functional outcomes (including knee stability, quadriceps values measurement, etc.) [3,4,5,6]. However, for symptomatic complete and combined PCL injuries, surgery is recommended to restore joint stability and improve function. Because, persistent instability of the knee due to posterior cruciate ligament tears, knee pain, limited mobility and osteoarthritis will occur in the future [7,8,9,10]. PCL reconstruction has a high failure rate due to incorrect tunnel placement, selection of inappropriate surgical techniques, grafts, timing of postoperative rehabilitation, and the presence of other associated complications (infection, pain, etc.) [11,12,13,14,15,16]. The results of a previous study showed that only 50–82% of the patients who underwent PCL reconstruction were able to return to the preinjury activity level . In addition, the incidence of joint degeneration after PCL reconstruction has been reported to be between 15 and 60% .
At present, there is no consensus on the reasons for the different biomechanical effects of PCL reconstruction, and the probable cause of PCL reconstruction failure is theorized to be incorrect tunnel location [11, 12, 19]. The acute flexion angle at the intra-articular interface between the graft and the tibial tunnel is known as the "killer turn" [20, 21]. Analogous to the ‘‘killer turn’’, an acute graft bending angle at the intra-articular femoral tunnel may result in early graft failure; this scenario is known as the “critical corner” or “acute angle”. The “critical corner” or “acute angle” from the femoral tunnel can cause graft failure [22, 23]. At present, several studies have shown that different placements of the femoral tunnel can lead to different biomechanical results [24,25,26,27,28,29]. However, until now, we have not identified one or more ideal tunnels, as well as their specific coordinates, that can effectively reduce the “critical corner” or “acute angle”.
Therefore, the present study aimed to confirm one or more ideal femoral tunnel points during PCL reconstruction that can reduce the “critical corner” via the three-dimensional (3D) finite element (FE) analysis. We hypothesized that these new points of the femur are useful for the correct-placing of the femoral tunnel; additionally, in these new points, the graft peak stress can be reduced.
Materials and methods
Establishment of a three-dimensional finite element model of the knee joint
A 35-year-old adult healthy male volunteer (175 cm, 75 kg) participated in the study and signed an informed consent form. The volunteer had no history of knee infection, injury or other conditions that may have affected the experiment. The subject was placed in the supine position, and the knee joint was fixed with a knee brace to reduce the movement of the knee joint during data collection.
Patient knee data were collected by using Siemens ingenuity core 64-slice spiral computed tomography (CT) and 1.5-T dual gradient nuclear magnetic resonance imaging (MRI, Siemens MAGNETOM Aera). CT scanning parameters(120kv, automatic milliampere-second scanning, scanning layer thickness 5 mm, reconstruction layer thickness 1 mm, matrix 512 × 512, radiation dose 20mgy (CTDIvol)); MRI scanning parameters (t1 sagittal bit, TSE sequence, layer thickness 3.5 mm, layer spacing 0.35 mm, TE: 12 ms, TR: 690 ms; PD sagittal lipid press, TSE sequence, layer thickness 3.5 mm, layer spacing 0.35 mm, TE: 35 ms, TR: 2980 ms; pd coronal lipogram, TSE sequence, layer thickness 3.5 mm, layer spacing 0.35, TE: 35 ms, TR: 2500 ms; t2-axis lipid press, TSE sequence, layer thickness 4 mm, layer spacing 0.4 mm, TE: 85 ms, TR: 3400 ms).
The volunteer's CT and MRI examinations showed no knee skeletal developmental deformities, meniscus injuries, periknee ligament injuries, and articular cartilage injuries. Knee CT data (distal femur, proximal tibia, proximal fibula and patella) and MRI data (cartilage, meniscus, anterior cruciate ligament, posterior cruciate ligament and medial and lateral collateral ligaments) were imported into Mimics Research 21.0 and 3D Slicer 4.10.2, respectively. The exported data were saved in the STL format.
The obtained STL data were imported into ZBrush 2019 to beautify and adjust the corresponding model. The data were output in OBJ format and imported into Rhino 7 for grid representation design. 3D models of different knee joints were made according to the experimental requirements.
Via Geomagic Design X 64, the mesh was divided and checked to make the mesh smoother and more flexible, thus ensuring a high-quality surface to complete the experiment. The model was divided into 2,599,237 cells and 3,727,928 nodes (Fig. 1). The finite element analysis software SOLIDWORKS 2018 was used to analyze the 3D geometric model of the knee joint.
The femur and tibia are considered to be rigid because their stiffness is significantly higher than that of soft tissue . According to previous literature reports, articular cartilage and meniscus are considered to be a single-phase linear elastic and isotropic material with elastic moduli of 5 MPa and 59 MPa, respectively, and the Poisson's ratios of articular cartilage and meniscus are 0.46 and 0.49, respectively [31, 32]. We set the ligament as a homogeneous, continuous, hyperelastic, rubber-like material, which represents the nonlinear stress‒strain relationships . Finally, to simulate the real-life knee structure, each accessory and tissue were anatomically linked.
Establishment of models with different bend angles
Flexion in the reconstructed knees was simulated as follows. After the PCL reconstruction model was created, the femur was immobilized, and the tibia was rotated posteriorly by using computer software. Different knee joint models with knee bends of 30°, 60° and 90° were obtained (Fig. 2).
Tibial and femoral tunnel placements
The tibial tunnel is located at the tibial footprint of the PCL. Based on our team's previous experiments, we adopted a similar tunnel design for the femur . In the distal femur, with the PCL anatomical site as the center, the distance of 5 mm was in the distal–proximal direction and in the direction. At the intersection of each point and the bone surface, femoral tunnels were established. A total of 25 tunnels were obtained from the first lateral tunnel near the medial condyle of the proximal femur. Among them, 5 tunnels were placed outside of the femur vault, which did not conform to the actual surgical procedures and were excluded. Therefore, we obtained 20 different femoral tunnel knee models. Among them, tunnel 13 is the PCL located in the middle of the anatomical footprint. The femoral and tibial tunnel diameters were uniformly set at 9 mm (Fig. 3).
We defined the position of the femoral tunnel relative to tunnel 13. We used the standard anatomical orientation for the partitioning, and we obtained the antero-proximal region, antero-distal region and posterior region (Fig. 4).
After the PCL reconstruction was complete, a posterior tibial load of 134 N was applied to the reconstructed model, and different tunnels of the femur, peak stress at knee angles of 0°, 30°, 60° and 90° and the displacement of the proximal tibia were recorded and compared. Knee stability was determined by measuring the size of the posterior displacement of the tibia relative to the femur. After the test, the peak stress of the grafts and the posterior displacement values of the tibia in different femoral tunnels were recorded and compared at different knee flexion angles (Fig. 5).
For the test and comparison of graft peak stress, in the antero-proximal region (in tunnels 2, 6, 8, 11 and 12), the peak stress of the graft was smaller than that of tunnel 13 (but only when the flexion was 60° and 90°). Notably, the peak stress of tunnel 12 was slightly smaller than that of tunnel 13 at 0° and was slightly larger than that of tunnel 13 at 30° (Fig. 6a). In the antero-distal region, the peak stress of grafts in tunnels 11, 12, 17 and 18 was lower than that in tunnels 13 at 60° and 90° of flexion. Furthermore, the peak stress of tunnel 18 was slightly greater than that of tunnel 13 at 0° flexion; additionally, with the increase in bending angle, the difference in peak stress between the two tunnels also increased (Fig. 7a). In the posterior region, the stress peaks of tunnels 4 and 8 were smaller than those of tunnel 13 at 60° and 90° of flexion and were opposite at 0° and 30° of flexion (Fig. 8a).
In the test and comparison of posterior tibial displacement, the displacement value of tunnel 12 was smaller than that of tunnel 13 at different flexion angles (Fig. 6b). The posterior tibial displacement of tunnel 18 was slightly smaller than that of tunnel 13 at 0° and 60° of flexion (but opposite at 30° and 90° of flexion) (Fig. 7b). Moreover, the posterior tibial displacement of tunnel 4 was slightly greater than that of tunnel 13 (but only at 30° flexion), and the other angles were smaller than that of tunnel 13 (Fig. 8b).
Therefore, after a comprehensive comparison, tunnel 12, tunnel 18 and tunnel 4 were selected as the best tunnels in the antero-proximal region, antero-distal region and posterior region, respectively. It is worth mentioning that tunnel 4 is located outside of the intercondylar fossa of the femur, wherein the tunnel is located, which is in contrast to the current surgical approach. Therefore, we ruled this tunnel out. Finally, we only obtained two ideal tunnels (tunnel 12 and tunnel 18).
The present study used a finite element analysis to determine the biomechanical effects of femoral tunnels at different locations on PCL reconstruction. The most important findings of this study are as follows: 1. compared with anatomical footpath tunnel 13, tunnel 12 and tunnel 18 can effectively reduce the peak stress of the graft, especially at high flexion angles (60° and 90°); and 2. compared with anatomical footmark tunnel 13, tunnels 12 and 18 did not increase the posterior displacement of the proximal tibia. Therefore, we hypothesized that tunnel 12 and tunnel 18 could effectively reduce the peak graft stress without reducing the posterior stability of the knee joint.
At present, biomechanical experiments have confirmed that the ‘‘killer turn’’ produced by grafts and tibia tunnels is one of the factors that contribute to the loosening and failure of grafts [35,36,37]. The “critical corner” or “acute angle”, whereby grafts and femoral tunnels form, is another potential risk factor [38,39,40]. During PCL reconstruction, an acute graft bending angle is formed at the interarticular interface between the graft and the femoral tunnel. Due to the presence of this acute angle, when the knee joint is stretched and flexed, the graft will constantly rub against the sharp edges of the femoral tunnel hole, thus resulting in excessive wear and stretching of the graft. The proper placement of tunnels to minimize “critical corner” or “acute angle” effects is essential for successful PCL reconstruction [40,41,42].
In the literature, there are relatively fewer finite element and biomechanical studies on the different positions of femoral tunnels. Seo et al.  reconstructed the anterolateral, central and posteromedial tunnels of the femoral footprint by using a single beam of three-dimensional finite element analysis and measured the changes in PCL tension at 0°, 45°, 90° and 135° of the knee bend. From their data, when the knee bends beyond 90°, the central tunnel graft is preferable to the other two types of grafts. The study focused on changes in graft tension and tested more angles of knee flexion than we tested. Since we did not test for knee flexion at 135°, this may be the reason why we cannot draw consistent conclusions. However, other scholars have obtained different conclusions about the biomechanical study of the different femoral tunnels. For example, Markolf et al.  conducted a biomechanical study to measure plant tension and length changes at six bend angles in the anterolateral, central and posteromedial regions of the femoral footprint. This study suggested that a posteromedial tunnel should not be used for single-bundle posterior cruciate ligament reconstruction. Moreover, Burns et al.  used 7 adult knee specimens to conduct biomechanical research. In the proximal and distal directions of the equidistant point, two femoral tunnels were built at a distance of 5 mm. They concluded that the distal femoral tunnel produced better posterior stability when increasing the knee bend angle than did the proximal or isometric tunnels. This is consistent with our conclusions, and the conclusion of our experiment on Tunnel 18 coincides with the conclusions of this study, except that our trial was designed to test the peak stress of the graft. Similarly, Galloway et al.  defined five femoral tunnels in an isometric position (the isometric points were 4 mm apart at the remaining four points) and showed that PCL reconstruction centered on isometric femoral attachment resulted in decreased posterior stability at high knee flexion angles. They concluded that the biomechanical effect of the PCL reconstruction was better when the graft was placed in the distal direction of the isometric point (near the isometric point 1/3 position). In contrast to this study, we did not design the femoral tunnel with a 4 mm spacing, and we used a posterior tibial load of 134 N instead of 100 N. The best location for the femoral tunnel to be established in this study is similar to the tunnel 18 we designed. This result is essentially consistent with our results.
However, there was no study focused on the other areas except for the 5 points. Although the methods and specific steps in our experiments were different, all of the experiments agreed that the best location for PCL for reconstructing the femoral tunnel was in the antero-distal region [28, 29, 43, 44]. Our study identified the specific coordinates of the ideal tunnel in the antero-distal region.
The finite element analysis, which resolves the limitation of traditional measurement tools, is an important method of biomechanical analysis. With the use of a computer design, the femoral tunnel can be extensively built, and small changes can be observed between the tunnels. In this experiment, 20 femoral tunnels were established, which was not limited in number compared with traditional cadaver specimens and which solved the problem of insufficient cadaver specimens. Unlike most current studies, we further considered the influence of the medial and lateral collateral ligaments and the anterior cruciate ligament to make the results more convincing. Moreover, our experiments tested both the peak stress of the graft and the posterior displacement of the proximal tibia.
Our study had the following limitations. First, this analysis only involved the finite element analysis of the anatomical geometry of one subject, and further in vitro biomechanical tests are needed. Second, in this study, only the influence of the femoral tunnel at different sites was explored, and the influence of tibial insertion was not explored. In previous studies, our team explored the influence of different positions of the tibial tunnel on PCL reconstruction . Finally, this was a theoretical analysis that requires further practical clinical verification.
In summary, among the options for PCL reconstruction of the femoral tunnel, the tunnels located 5 mm distal to the footprint and 5 mm anterior to the footprint could reduce the peak stress of the graft. In addition, they may reduce the "critical corner" and were shown to not reduce the posterior stability of the knee joint.
Availability of data and materials
The datasets used and/or analyzed during the current study are available.
from the corresponding author on reasonable request.
Magnetic resonance imaging
Posterior cruciate ligament
Fanelli GC, Edson CJ. Posterior cruciate ligament injuries in trauma patients: Part II. Arthroscopy. 1995;11(5):526–9.
Clancy WG Jr, Sutherland TB. Combined posterior cruciate ligament injuries. Clin Sports Med. 1994;13(3):629–47.
Bedi A, Musahl V, Cowan JB. Management of Posterior Cruciate Ligament Injuries: An Evidence-Based Review. J Am Acad Orthop Surg. 2016;24(5):277–89.
Lu CC, Yao HI, Fan TY, Lin YC, Lin HT, Chou PP. Twelve Weeks of a Staged Balance and Strength Training Program Improves Muscle Strength, Proprioception, and Clinical Function in Patients with Isolated Posterior Cruciate Ligament Injuries. Int J Environ Res Public Health. 2021;18(23):12849.
Parolie JM, Bergfeld JA. Long-term results of nonoperative treatment of isolated posterior cruciate ligament injuries in the athlete. Am J Sports Med. 1986;14(1):35–8.
Schüttler KF, Ziring E, Ruchholtz S, Efe T. Posterior cruciate ligament injuries. Unfallchirurg. 2017;120(1):55–68.
Kohen RB, Sekiya JK. Single-bundle versus double-bundle posterior cruciate ligament reconstruction. Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association. 2009;25(12):1470–7.
Razi M, Ghaffari S, Askari A, Arasteh P, Ziabari EZ, Dadgostar H. An evaluation of posterior cruciate ligament reconstruction surgery. BMC Musculoskelet Disord. 2020;21(1):526.
Boynton MD, Tietjens BR. Long-term followup of the untreated isolated posterior cruciate ligament-deficient knee. Am J Sports Med. 1996;24(3):306–10.
Winkler PW, Zsidai B, Wagala NN, Hughes JD, Horvath A, Senorski EH, Samuelsson K, Musahl V. Evolving evidence in the treatment of primary and recurrent posterior cruciate ligament injuries, part 2: surgical techniques, outcomes and rehabilitation. Knee Surg, Sports Traumato, Arthrosc : official journal of the ESSKA. 2021;29(3):682–93.
Fanelli GC, Fanelli MG, Fanelli DG. Revision Posterior Cruciate Ligament Surgery. Sports Med Arthrosc Rev. 2017;25(1):30–5.
Noyes FR, Barber-Westin SD. Posterior cruciate ligament revision reconstruction, part 1: causes of surgical failure in 52 consecutive operations. Am J Sports Med. 2005;33(5):646–54.
Fanelli GC, Beck JD, Edson CJ. Current concepts review: the posterior cruciate ligament. J Knee Surg. 2010;23(2):61–72.
de Villiers C, Goetz G, Sadoghi P, Geiger-Gritsch S. Comparative Effectiveness and Safety of Allografts and Autografts in Posterior Cruciate Ligament Reconstruction Surgery: A Systematic Review. Arthroscopy, sports medicine, and rehabilitation. 2020;2(6):e893–907.
Chen YJ, Yang CP, Ho CS, Weng CJ, Chen AC, Hsu WH, Hsu KY, Chan YS. Midterm Outcomes After Revision Posterior Cruciate Ligament Reconstruction With a Single-Bundle Transtibial Autograft. Orthop J Sports Med. 2022;10(8):23259671221115424.
Durbin TC, Johnson DL. Pearls and pitfalls of single-bundle transtibial posterior cruciate ligament reconstruction. Orthopedics. 2012;35(3):218–23.
Hammoud S, Reinhardt KR, Marx RG. Outcomes of posterior cruciate ligament treatment: a review of the evidence. Sports Med Arthrosc Rev. 2010;18(4):280–91.
Kernkamp WA, Jens AJT, Varady NH, van Arkel ERA, Nelissen R, Asnis PD, LaPrade RF, Van de Velde SK, Li G. Anatomic is better than isometric posterior cruciate ligament tunnel placement based upon in vivo simulation. Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA. 2019;27(8):2440–9.
McAllister DR, Hussain SM. Tibial inlay posterior cruciate ligament reconstruction: surgical technique and results. Sports Med Arthrosc Rev. 2010;18(4):249–53.
Lee YS, Jung YB. Posterior cruciate ligament: focus on conflicting issues. Clin Orthop Surg. 2013;5(4):256–62.
Huang T-W, Wang C-J, Weng L-H, Chan Y-S. Reducing the “killer turn” in posterior cruciate ligament reconstruction Arthroscopy. The J Arthrosc Related Surg. 2003;19(7):712–6.
Schoderbek RJ Jr, Golish SR, Rubino LJ, Oliviero JA, Hart JM, Miller MD. The graft/femoral tunnel angles in posterior cruciate ligament reconstruction: a comparison of 3 techniques for femoral tunnel placement. J Knee Surg. 2009;22(2):106–10.
Jang K-M, Park S-C, Lee D-H. Graft Bending Angle at the Intra-articular Femoral Tunnel Aperture After Single-Bundle Posterior Cruciate Ligament Reconstruction. Am J Sports Med. 2016;44(5):1269–75.
Markolf KL, Jackson SR, McAllister DR. Single- versus double-bundle posterior cruciate ligament reconstruction: effects of femoral tunnel separation. Am J Sports Med. 2010;38(6):1141–6.
Markolf KL, Slauterbeck JR, Armstrong KL, Shapiro MS, Finerman GA. A biomechanical study of replacement of the posterior cruciate ligament with a graft. Part II: Forces in the graft compared with forces in the intact ligament. J Bone Joint Surg Am. 1997;79(3):381–6.
Pearsall AT, Pyevich M, Draganich LF, Larkin JJ, Reider B. In vitro study of knee stability after posterior cruciate ligament reconstruction. Clin Orthop Relat Res. 1996;327:264–71.
Seo YJ, Song SY, Kim IS, Seo MJ, Kim YS, Yoo YS. Graft tension of the posterior cruciate ligament using a finite element model. Knee Surg Sports Traumatol Arthrosc. 2014;22(9):2057–63.
Markolf KL, Feeley BT, Jackson SR, McAllister DR. Where should the femoral tunnel of a posterior cruciate ligament reconstruction be placed to best restore anteroposterior laxity and ligament forces? Am J Sports Med. 2006;34(4):604–11.
Burns WC 2nd, Draganich LF, Pyevich M, Reider B. The effect of femoral tunnel position and graft tensioning technique on posterior laxity of the posterior cruciate ligament-reconstructed knee. Am J Sports Med. 1995;23(4):424–30.
Peña E, Calvo B, Martínez MA, Doblaré M. A three-dimensional finite element analysis of the combined behavior of ligaments and menisci in the healthy human knee joint. J Biomech. 2006;39(9):1686–701.
LeRoux MA, Setton LA. Experimental and biphasic FEM determinations of the material properties and hydraulic permeability of the meniscus in tension. J Biomech Eng. 2002;124(3):315–21.
Li G, Lopez O, Rubash H. Variability of a three-dimensional finite element model constructed using magnetic resonance images of a knee for joint contact stress analysis. J Biomech Eng. 2001;123(4):341–6.
Kim JG, Kang KT, Wang JH. Biomechanical Difference between Conventional Transtibial Single-Bundle and Anatomical Transportal Double-Bundle Anterior Cruciate Ligament Reconstruction Using Three-Dimensional Finite Element Model Analysis. J Clin Med. 2021;10(8):1625.
Wang Z, Xiong Y, Li Q, Chen G, Zhang Z, Tang X, Li J. Evaluation of tibial tunnel placement in single case posterior cruciate ligament reconstruction: reducing the graft peak stress may increase posterior tibial translation. BMC Musculoskelet Disord. 2019;20(1):521.
Bergfeld JA, McAllister DR, Parker RD, Valdevit AD, Kambic HE. A biomechanical comparison of posterior cruciate ligament reconstruction techniques. Am J Sports Med. 2001;29(2):129–36.
Markolf KL, Zemanovic JR, McAllister DR. Cyclic loading of posterior cruciate ligament replacements fixed with tibial tunnel and tibial inlay methods. J Bone Joint Surg Am. 2002;84(4):518–24.
Lin Y, Cai W, Huang X, Li J, Li Q: [The killer turn in the posterior cruciate ligament reconstruction: mechanism and improvement]. Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 2020, 34(6):787–792.
Mariani PP, Adriani E, Bellelli A, Maresca G. Magnetic resonance imaging of tunnel placement in posterior cruciate ligament reconstruction. Arthroscopy. 1999;15(7):733–40.
Weiss WM. Editorial Commentary: Posterior Cruciate Ligament Femoral Techniques: The “Critical Corner” Is Just Not as Exciting as the “Killer Turn.” Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association. 2019;35(4):1195–6.
Narvy SJ, Hatch GF 3rd, Ihn HE, Heckmann ND, McGarry MH, Tibone JE, Lee TQ. Evaluating the Femoral-Side Critical Corner in Posterior Cruciate Ligament Reconstruction: The Effect of Outside-In Versus Inside-Out Creation of Femoral Tunnels on Graft Contact Pressure in a Synthetic Knee Model. Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association. 2017;33(7):1370–4.
Fanelli GC. PCL Transtibial Tunnel Reconstruction. Sports Med Arthrosc Rev. 2020;28(1):8–13.
Jang KM, Park SC, Lee DH. Graft Bending Angle at the Intra-articular Femoral Tunnel Aperture After Single-Bundle Posterior Cruciate Ligament Reconstruction: Inside-Out Versus Outside-In Techniques. Am J Sports Med. 2016;44(5):1269–75.
Galloway MT, Grood ES, Mehalik JN, Levy M, Saddler SC, Noyes FR. Posterior cruciate ligament reconstruction. An in vitro study of femoral and tibial graft placement. Am j Sports Med. 1996;24(4):437–45.
Jung M, Song SY, Cha M, Chung HM, Kim YS, Jang SW, Seo YJ. Graft bending angle of the reconstructed posterior cruciate ligament gradually decreases as knee flexion increases. Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA. 2020;28(8):2626–33.
The authors wish to express their gratitude to the volunteer in the three-dimensional finite element test and biomechanics expert Tingwu Qin, state key laboratory of biomechanics, west China hospital, Sichuan University.
This research was funded by the Youth Innovation Project of Medical Research of Sichuan Medical Association and the Annual "Xing lin Scholars" Talent Research Promotion Program of Chengdu University of Traditional Chinese Medicine. All of this funding supported the design of the study, collection, analysis, and interpretation of the data.
Ethics approval and consent to participate
This study was approved by the Medical Research Ethics Committee of Suining Central Hospital (Ethics Code LLSNCH20200060). This research was conducted in full compliance with the codes of ethical conduct from the Declaration of Helsinki. Written informed consent were obtained from the patients before they were enrolled in the study.
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Wang, B., Ye, Y., Yao, L. et al. Different femoral tunnel placement in posterior cruciate ligament reconstruction: a finite element analysis. BMC Musculoskelet Disord 24, 93 (2023). https://doi.org/10.1186/s12891-023-06161-y
- Critical corner
- Posterior cruciate ligament
- Finite element
- Knee joint injury