An anteromedial stabilization procedure has the most protective effect on the anterior cruciate ligament in tibial external rotation. A human knee model study

Fabian Blanke; Matthias Boljen; Nicola Oehler; Christoph Lutter; Thomas Tischer; Stephan Vogt

doi:10.1007/s00402-024-05357-8

An anteromedial stabilization procedure has the most protective effect on the anterior cruciate ligament in tibial external rotation. A human knee model study

Arch Orthop Trauma Surg. 2024 May 10. doi: 10.1007/s00402-024-05357-8. Online ahead of print.

Authors

Fabian Blanke^{1

2

3}, Matthias Boljen⁴, Nicola Oehler⁵, Christoph Lutter⁶, Thomas Tischer⁶, Stephan Vogt⁵

Affiliations

¹ Department of Knee-, Shoulder- and Hip-Surgery and Orthopedic Sports Medicine, Schön Klinik München Harlaching, München, Germany. fblanke@gmx.de.
² Department of Orthopedic Surgery, University Rostock, Rostock, Germany. fblanke@gmx.de.
³ Department of Orthopedic Sports Medicine and Arthroscopic Surgery, Hessing Stiftung Augsburg, Augsburg, Germany. fblanke@gmx.de.
⁴ Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut, EMI, Freiburg i, Breisgau, Germany.
⁵ Department of Orthopedic Sports Medicine and Arthroscopic Surgery, Hessing Stiftung Augsburg, Augsburg, Germany.
⁶ Department of Orthopedic Surgery, University Rostock, Rostock, Germany.

PMID: 38727813
DOI: 10.1007/s00402-024-05357-8

Abstract

Introduction: Anterior cruciate ligament (ACL) reconstruction remains associated with the risk of re-rupture and persisting rotational instability. Additional extraarticular anterolateral stabilization procedures stabilize the tibial internal rotation and lead to lower ACL failure rate and improved knee stability. However, data for additional stabilization of tibial external rotation is lacking and the importance of an anteromedial stabilization procedure is less well evaluated. Aim of this study is to investigate the influence of an extraarticular anteromedial stabilization procedure for the stabilization of the tibial external rotation and protection of the ACL from these rotational forces.

Methods: Internal and external rotations of the tibia were applied to a finite element (FE) model with anatomical ACL, posterior cruciate ligament (PCL), lateral collateral ligament (LCL), medial collateral ligament (MCL) and intact medial and lateral meniscus. Five additional anatomic structures (Anteromedial stabilization/anteromedial ligament, AML, augmented superficial medial collateral ligament, sMCL, posterior oblique ligament, POL, anterolateral ligament, ALL, and popliteal tendon, PLT) were added to the FE model separately and then combined. The force histories within all structures were measured and determined for each case.

Results: The anteromedial stabilization or imaginary AML was the main secondary stabilizer of tibial external rotation (90% of overall ACL force reduction). The AML reduced the load on the ACL by 9% in tibial external rotation which could not be achieved by an augmented sMCL (-1%). The AML had no influence in tibial internal rotation (-1%). In the combined measurements with all additional structures (AML, ALL, PLT, POL) the load on the ACL was reduced by 10% in tibial external rotation.

Conclusion: This study showed that an additional anteromedial stabilization procedure secures the tibial external rotation and has the most protective effect on the ACL during these external rotational forces.

Keywords: ACL rupture; ALL; AML; Anteromedial stabilization.