Technical considerations in lateral extra-articular reconstruction coupled with anterior cruciate ligament reconstruction: A simulation study evaluating the influence of surgical parameters on control of knee stability

Abstract

Background: Surgical parameters such as the selection of tibial and femoral attachment site, graft tension, and knee flexion angle at the time of fixation may influence the control of knee stability after lateral extra-articular reconstruction. This study aimed to determine how sensitive is the control of knee rotation and translation, during simulated pivot-shift scenarios, to these four surgery settings. Methods: A computer model was used to simulate 625 lateral extra-articular reconstructions based upon five different variations of each of the following parameters: femoral and tibial attachment sites, knee flexion angle and graft tension at the time of fixation. For each simulated surgery, the lateral extra-articular reconstruction external rotation moment at the knee joint center was computed during simulated pivot-shift scenarios. The sensitivity of the control of knee rotation and translation to a given surgery setting was assessed by calculating the coefficient of variation of the lateral extra-articular reconstruction external rotation moment. Findings: Graft tension had minimal influence on the control of knee rotation and translation with less than 2.4% of variation across the scenarios tested. Control of knee rotation and translation was the least affected by the femoral attachment site if the knee was close to full extension at the time of graft fixation. The choice of the tibial attachment site was crucial when the femoral fixation was proximal and posterior to the femoral epicondyle since 15 to 67% of variation was observed in the control of knee rotation and translation. Interpretation: Femoral and tibial attachment sites as well as knee flexion angle at the time of fixation should be considered by surgeons when performing lateral extra-articular reconstruction. Variation in graft tension between the ranges 20-40 N has minimal influence on the control of knee rotation and translation.

Different anterolateral procedures have variable impact on knee kinematics and stability when performed in combination with anterior cruciate ligament reconstruction

“…A more convincing argument was first introduced by Amis 42 and then recently confirmed in a biomechanical study, 40 and concerns the difference in geometry between anatomical fixation points of the grafts. While there is no difference in the femoral insertion point between the two techniques (they both use a tunnel positioned posterior and proximal to the femoral epicondyle), there is a difference in their tibial attachment sites.…”

Lateral tenodesis procedures increase lateral compartment pressures more than anterolateral ligament reconstruction, when performed in combination with ACL reconstruction: a pilot biomechanical study

“…It could explain the differential in LTF contact pressures observed between the ALLR and Lemaire procedures. 46 While there is no difference in the femoral insertion point between both techniques (they both use a tunnel positioned posterior and proximal to the femoral epicondyle), there is a difference in their tibial attachment sites. The tibial positioning of the Lemaire procedures is located at the level of the GT, which is therefore anterior (approximately 18 to 20 mm) from that of the ALLR.…”

Towards a validated musculoskeletal knee model to estimate tibiofemoral kinematics and ligament strains: comparison of different anterolateral augmentation procedures combined with isolated ACL reconstructions

“…However, the FD IR values showed a smaller range of variation than the experimental results [ 26 ]. The 5Nm ER [ 25 , 26 ] torque caused the models to externally rotate by around 2.5–10°, compared to the literature range of 0–30° [ 29 , 30 ], across 0–100° of knee flexion.

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