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Review
. 2018 May 13:2018:4657824.
doi: 10.1155/2018/4657824. eCollection 2018.

A Review on Biomechanics of Anterior Cruciate Ligament and Materials for Reconstruction

M Marieswaran  1 , Ishita Jain  2 , Bhavuk Garg  3 , Vijay Sharma  3   4 , Dinesh Kalyanasundaram  1   5
Affiliations
Review

A Review on Biomechanics of Anterior Cruciate Ligament and Materials for Reconstruction

M Marieswaran et al. Appl Bionics Biomech. .

Abstract

The anterior cruciate ligament is one of the six ligaments in the human knee joint that provides stability during articulations. It is relatively prone to acute and chronic injuries as compared to other ligaments. Repair and self-healing of an injured anterior cruciate ligament are time-consuming processes. For personnel resuming an active sports life, surgical repair or replacement is essential. Untreated anterior cruciate ligament tear results frequently in osteoarthritis. Therefore, understanding of the biomechanics of injury and properties of the native ligament is crucial. An abridged summary of the prominent literature with a focus on key topics on kinematics and kinetics of the knee joint and various loads acting on the anterior cruciate ligament as a function of flexion angle is presented here with an emphasis on the gaps. Briefly, we also review mechanical characterization composition and anatomy of the anterior cruciate ligament as well as graft materials used for replacement/reconstruction surgeries. The key conclusions of this review are as follows: (a) the highest shear forces on the anterior cruciate ligament occur during hyperextension/low flexion angles of the knee joint; (b) the characterization of the anterior cruciate ligament at variable strain rates is critical to model a viscoelastic behavior; however, studies on human anterior cruciate ligament on variable strain rates are yet to be reported; (c) a significant disparity on maximum stress/strain pattern of the anterior cruciate ligament was observed in the earlier works; (d) nearly all synthetic grafts have been recalled from the market; and (e) bridge-enhanced repair developed by Murray is a promising technique for anterior cruciate ligament reconstruction, currently in clinical trials. It is important to note that full extension of the knee is not feasible in the case of most animals and hence the loading pattern of human ACL is different from animal models. Many of the published reviews on the ACL focus largely on animal ACL than human ACL. Further, this review article summarizes the issues with autografts and synthetic grafts used so far. Autografts (patellar tendon and hamstring tendon) remains the gold standard as nearly all synthetic grafts introduced for clinical use have been withdrawn from the market. The mechanical strength during the ligamentization of autografts is also highlighted in this work.

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Figures

Figure 1
Figure 1
(a) ACL of a cadaver knee shown connecting the femur to the tibia. (b) A torn ACL.
Figure 2
Figure 2
Composition of ligaments and tendons.
Figure 3
Figure 3
Schematic showing the hierarchy involved in the ligament [18].
Figure 4
Figure 4
Tensile strength of ACL and the patellar tendon [33]. The dotted lines represent the toe region, continuous lines represent the linear region, and dashed/broken lines represent the yield region.
Figure 5
Figure 5
Average strain in AMB and PLB as a function of knee flexion angle; as shown in the figure, AMB is under tension during the extension at the knee joint and PLB is under tension during flexion [32].
Figure 6
Figure 6
(a) Illustrating the change in the center of rotation (CoR) of the femur over the tibia (positions 1 to 10) (dotted lines indicate radii of rotation). (b) Arbitrarily selected anatomical positions during rotation.
Figure 7
Figure 7
Forces acting at the knee joint [41]. TF: Tibiofemoral joint force; PT: patellar tendon force; HAMS: hamstring muscle force; GAS: gastrocnemius muscle force; GRF: ground reaction force.
Figure 8
Figure 8
(a, b) The effect of combined loading on ACL force during knee flexion angles [42]. (c, d) The effect of combined loading on ACL force during knee flexion angles [42].
Figure 9
Figure 9
Forces acting on ACL during a simulated gait cycle along with changes in the knee angle during the gait cycle [41, 55].
Figure 10
Figure 10
Comparison of failure force for autografts at various time points post ACL replacement surgery with intact ACL. ∗Significant difference (p < 0.05) between autografts and intact ACL for the corresponding time period [61, 62].
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References

    1. Tortora G. J., Derrickson B. H. 12th. Hoboken, NJ, USA: John Wiley & Sons Inc; 2009.
    1. Boden B. P., Dean G. S., Feagin J. A., Jr., Garrett W. E., Jr. Mechanisms of anterior cruciate ligament injury. 2000;23(6):573–578. - PubMed
    1. Ferretti A., Papandrea P., Conteduca F., Mariani P. P. Knee ligament injuries in volleyball players. 1992;20(2):203–207. doi: 10.1177/036354659202000219. - DOI - PubMed
    1. McNair P. J., Marshall R. N., Matheson J. A. Important features associated with acute anterior cruciate ligament injury. 1990;103(901):537–539. - PubMed
    1. Olsen O. E., Myklebust G., Engebretsen L., Holme I., Bahr R. Relationship between floor type and risk of ACL injury in team handball. 2003;13(5):299–304. doi: 10.1034/j.1600-0838.2003.00329.x. - DOI - PubMed