Anterior Tibial Translation During Progressive Loading of the ACL-Deficient Knee During Weight-Bearing and Nonweight-Bearing Isometric Exercise

Background: The individual kinematic roles of the anterolateral ligament (ALL) and the distal iliotibial band Kaplan fibers in the setting of anterior cruciate ligament (ACL) deficiency require further clarification. This will improve understanding of their potential contribution to residual anterolateral rotational laxity after ACL reconstruction and may influence selection of an anterolateral extra-articular reconstruction technique, which is currently a matter of debate. Hypothesis/Purpose: To compare the role of the ALL and the Kaplan fibers in stabilizing the knee against tibial internal rotation, anterior tibial translation, and the pivot shift in ACL-deficient knees. We hypothesized that the Kaplan fibers would provide greater tibial internal rotation restraint than the ALL in ACL-deficient knees and that both structures would provide restraint against internal rotation during a simulated pivot-shift test. Study Design: Controlled laboratory study. Methods: Ten paired fresh-frozen cadaveric knees (n = 20) were used to investigate the effect of sectioning the ALL and the Kaplan fibers in ACL-deficient knees with a 6 degrees of freedom robotic testing system. After ACL sectioning, sectioning was randomly performed for the ALL and the Kaplan fibers. An established robotic testing protocol was utilized to assess knee kinematics when the specimens were subjected to a 5-N·m internal rotation torque (0°-90° at 15° increments), a simulated pivot shift with 10-N·m valgus and 5-N·m internal rotation torque (15° and 30°), and an 88-N anterior tibial load (30° and 90°). Results: Sectioning of the ACL led to significantly increased tibial internal rotation (from 0° to 90°) and anterior tibial translation (30° and 90°) as compared with the intact state. Significantly increased internal rotation occurred with further sectioning of the ALL (15°-90°) and Kaplan fibers (15°, 60°-90°). At higher flexion angles (60°-90°), sectioning the Kaplan fibers led to significantly greater internal rotation when compared with ALL sectioning. On simulated pivot-shift testing, ALL sectioning led to significantly increased internal rotation and anterior translation at 15° and 30°; sectioning of the Kaplan fibers led to significantly increased tibial internal rotation at 15° and 30° and anterior translation at 15°. No significant difference was found when anterior tibial translation was compared between the ACL/ALL- and ACL/Kaplan fiber–deficient states on simulated pivot-shift testing or isolated anterior tibial load. Conclusion: The ALL and Kaplan fibers restrain internal rotation in the ACL-deficient knee. Sectioning the Kaplan fibers led to greater tibial internal rotation at higher flexion angles (60°-90°) as compared with ALL sectioning. Additionally, the ALL and Kaplan fibers contribute to restraint of the pivot shift and anterior tibial translation in the ACL-deficient knee. Clinical Relevance: This study reports that the ALL and distal iliotibial band Kaplan fibers restrain anterior tibial translation, internal rotation, and pivot shift in the ACL-deficient knee. Furthermore, sectioning the Kaplan fibers led to significantly greater tibial internal rotation when compared with ALL sectioning at high flexion angles. These results demonstrate increased rotational knee laxity with combined ACL and anterolateral extra-articular knee injuries and may allow surgeons to optimize the care of patients with this injury pattern.

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Effect of Meniscocapsular and Meniscotibial Lesions in ACL-Deficient and ACL-Reconstructed Knees: A Biomechanical Study

The American Journal of Sports Medicine ◽

10.1177/0363546518774315 ◽

2018 ◽

Vol 46 (10) ◽

pp. 2422-2431 ◽

Cited By ~ 35

Author(s):

Nicholas N. DePhillipo ◽

Gilbert Moatshe ◽

Alex Brady ◽

Jorge Chahla ◽

Zachary S. Aman ◽

...

Keyword(s):

Internal Rotation ◽

Medial Meniscus ◽

Pivot Shift ◽

External Rotation ◽

Posterior Horn ◽

Pivot Shift Test ◽

Anterior Tibial Translation ◽

Anterior Tibial ◽

Tibial Translation ◽

Acl Deficient

Background: Ramp lesions were initially defined as a tear of the peripheral attachment of the posterior horn of the medial meniscus at the meniscocapsular junction. The separate biomechanical roles of the meniscocapsular and meniscotibial attachments of the posterior medial meniscus have not been fully delineated. Purpose: To evaluate the biomechanical effects of meniscocapsular and meniscotibial lesions of the posterior medial meniscus in anterior cruciate ligament (ACL)–deficient and ACL-reconstructed knees and the effect of repair of ramp lesions. Study Design: Controlled laboratory study. Methods: Twelve matched pairs of human cadaveric knees were evaluated with a 6 degrees of freedom robotic system. All knees were subjected to an 88-N anterior tibial load, internal and external rotation torques of 5 N·m, and a simulated pivot-shift test of 10-N valgus force coupled with 5-N·m internal rotation. The paired knees were randomized to the cutting of either the meniscocapsular or the meniscotibial attachments after ACL reconstruction (ACLR). Eight comparisons of interest were chosen before data analysis was conducted. Data from the intact state were compared with data from the subsequent states. The following states were tested: intact (n = 24), ACL deficient (n = 24), ACL deficient with a meniscocapsular lesion (n = 12), ACL deficient with a meniscotibial lesion (n = 12), ACL deficient with both meniscocapsular and meniscotibial lesions (n = 24), ACLR with both meniscocapsular and meniscotibial lesions (n = 16), and ACLR with repair of both meniscocapsular and meniscotibial lesions (n = 16). All states were compared with the previous states. For the repair and reconstruction states, only the specimens that underwent repair were compared with their intact and sectioned states, thus excluding the specimens that did not undergo repair. Results: Cutting the meniscocapsular and meniscotibial attachments of the posterior horn of the medial meniscus significantly increased anterior tibial translation in ACL-deficient knees at 30° ( P ≤ .020) and 90° ( P < .005). Cutting both the meniscocapsular and meniscotibial attachments increased tibial internal (all P > .004) and external (all P < .001) rotation at all flexion angles in ACL-reconstructed knees. Reconstruction of the ACL in the presence of meniscocapsular and meniscotibial tears restored anterior tibial translation ( P > .053) but did not restore internal rotation ( P < .002), external rotation ( P < .002), and the pivot shift ( P < .05). To restore the pivot shift, an ACLR and a concurrent repair of the meniscocapsular and meniscotibial lesions were both necessary. Repairing the meniscocapsular and meniscotibial lesions after ACLR did not restore internal rotation and external rotation at angles >30°. Conclusion: Meniscocapsular and meniscotibial lesions of the posterior horn of the medial meniscus increased knee anterior tibial translation, internal and external rotation, and the pivot shift in ACL-deficient knees. The pivot shift was not restored with an isolated ACLR but was restored when performed concomitantly with a meniscocapsular and meniscotibial repair. However, the effect of this change was minimal; although statistical significance was found, the overall clinical significance remains unclear. The ramp lesion repair used in this study failed to restore internal rotation and external rotation at higher knee flexion angles. Further studies should examine improved meniscus repair techniques for root tears combined with ACLRs. Clinical Relevance: Meniscal ramp lesions should be repaired at the time of ACLR to avoid continued knee instability (anterior tibial translation) and to eliminate the pivot-shift phenomenon.

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Slope reduction osteotomy decreases ACL graft forces and reduces anterior tibial translation under axial load - a biomechanical study

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967119s00217 ◽

2019 ◽

Vol 7 (6_suppl4) ◽

pp. 2325967119S0021

Author(s):

Florian B. Imhoff ◽

Julian Mehl ◽

Elifho Obopilwe ◽

Andreas Imhoff ◽

Knut Beitzel

Keyword(s):

Axial Load ◽

Wedge Osteotomy ◽

Anterior Tibial Translation ◽

Anterior Drawer ◽

Acl Graft ◽

Closing Wedge Osteotomy ◽

Closing Wedge ◽

Anterior Tibial ◽

Tibial Translation ◽

Acl Deficient

Aims and Objectives: To perform an anterior closing wedge osteotomy by 10° for slope reduction and investigate the effect of axial load and anterior drawer on forces on ACL graft, strain and femoro-tibial kinematics in a native, ACL-deficient and reconstructed knee. Materials and Methods: Ten cadaveric knees with an increased native slope were selected for this study based on CT meas-urements. An anterior closing-wedge osteotomy was performed by 10° and fixed with an external fixator. Tibial axial load (200 N, 400 N) was applied, while the tibial side was mounted on a free mov-ing X-Y-table with open rotation in 30° of knee flexion. Additionally, an anterior drawer (134 N) was performed with and without axial load (200 N). Specimens underwent native testing, cut ACL, and reconstructed ACL with a standardized quadruple semi-t/gracilis-allograft. Each condition was ran-domly tested with native slope and reduced slope. Change of forces on ACL-graft (attached load-cell) and strain on native ACL (via DVRT) were recorded. Throughout testing, 3D motion tracking captured anterior tibial translation (ATT) and rotation versus the fixed femur. Results: Preoperative, specimens showed an averaged lateral and medial slope of (average ±SD) 10° ± 1.4°, and age 48.2 ± 5.8years. Slope reduction significantly decreased forces on ACL graft by 17% (p=0.001) at 200 N and by 33% (p=0.0001) at 400 N of axial load. Furthermore, ATT was significantly decreased after slope reduc-tion in native (p=0.01), cut (p=0.005), and ACL-graft (p=0.01) status. Strain in native ACL de-creased by 9.7 ± 0.13% (p<0.0001) after slope reduction without any load. However, anterior drawer without axial load maintained significantly higher anterior tibial translation (native-pre 4.12 ± 0.65 mm vs. native-post 5.82 ± 1.51 mm, cut-ACL-pre 9.35 ± 1.57 mm vs cut-ACL-post 12.0 ± 3.53 mm, ACL-recon-pre 4.60 ± 0.97 mm vs. ACL-recon-post 5.73 ± 1.45 mm) and significantly higher forces on ACL graft (p=0.0006) after osteotomy. When axial load was combined with anterior drawer no significant change on ATT after osteotomy was observed. Rotational analysis did show a significant effect in the ACL cut condition due to slope correction. Overall, native and reconstruct-ed ACL showed the same tibial kinematics throughout testing. Conclusion: In general, osteotomy lowered ACL graft force and ACL strain when the joint was axially loaded. Anterior tibial translation was reduced even in an ACL deficient knee. When anterior drawer was performed without axial load, ATT was higher after slope reduction in every condition.

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Medial and lateral meniscus have a different role in kinematics of the ACL-deficient knee: a systematic review

Journal of ISAKOS Joint Disorders & Orthopaedic Sports Medicine ◽

10.1136/jisakos-2019-000293 ◽

2019 ◽

Vol 4 (5) ◽

pp. 233-241

Author(s):

Alberto Grassi ◽

Giacomo Dal Fabbro ◽

Stefano Di Paolo ◽

Federico Stefanelli ◽

Luca Macchiarola ◽

...

Keyword(s):

Systematic Review ◽

Medial Meniscus ◽

Lateral Meniscus ◽

Meniscus Tear ◽

Pivot Shift Test ◽

Anterior Tibial ◽

Kinematic Evaluation ◽

Tibial Translation ◽

Acl Deficient ◽

Deficient Knee

ImportanceMeniscal tears are frequently associated with anterior cruciate ligament (ACL) injury and the correct management of this kind of lesion during ACL-reconstruction procedure is critical for the restoration of knee kinematics. Although the importance of meniscus in knee biomechanics is generally accepted, the influence of medial and lateral meniscus in stability of ACL-deficient knee is still unclear.ObjectiveThe aim of this study was to review literature, which analysed effects in cadaveric specimens of meniscal tear and meniscectomy of medial and lateral meniscus on laxity in the ACL-deficient knee.Evidence reviewAuthors performed a systematic search for cadaveric studies analysing the effect of medial and lateral meniscus tears or resection on kinematics of ACL-deficient knee. Extracted data included year of publications, number of human cadaver knee specimens, description of apparatus testing and instrumented kinematic evaluation, testing protocol and results.FindingsAuthors identified 18 studies that met inclusion and exclusion criteria of current review. The major finding of the review was that the works included reported a difference role of medial and lateral meniscus in restraining ACL-deficient knee laxity. Medial meniscus tear or resection resulted in a significant increase of anterior tibial displacement. Lateral meniscus lesions or meniscectomy on the other hand significantly increased rotation and translation under a coupled valgus stress and internal-rotation torque/pivot shift test.ConclusionsMedial and lateral meniscus have a different role in stabilising the ACL-deficient knee: while the medial meniscus functions as a critical secondary stabilisers of anterior tibial translation under an anterior/posterior load, lateral meniscus appears to be a more important restraint of rotational and dynamic laxity.Level of evidenceLevel IV, systematic review of level I–IV studies.

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Nonweight-bearing anterior knee laxity is related to anterior tibial translation during transition from nonweight bearing to weight bearing

Journal of Orthopaedic Research® ◽

10.1002/jor.20040 ◽

2006 ◽

Vol 24 (3) ◽

pp. 516-523 ◽

Cited By ~ 30

Author(s):

Sandra J. Shultz ◽

Yohei Shimokochi ◽

Anh-Dung Nguyen ◽

Jatin P. Ambegaonkar ◽

Randy J. Schmitz ◽

...

Keyword(s):

Weight Bearing ◽

Knee Laxity ◽

Anterior Tibial Translation ◽

Anterior Knee Laxity ◽

Anterior Tibial ◽

Tibial Translation ◽

Anterior Knee

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Effect of Femoral Antetorsion on Tibiofemoral Translation and Rotation in the Anterior Cruciate Ligament Deficient Knee

The Journal of Knee Surgery ◽

10.1055/s-0038-1672198 ◽

2018 ◽

Vol 32 (10) ◽

pp. 960-965

Author(s):

Mohamed Omar ◽

Yousif Al Saiegh ◽

Emmanouil Liodakis ◽

Timo Stuebig ◽

Daniel Guenther ◽

...

Keyword(s):

Distal Femur ◽

Pivot Shift ◽

Cruciate Ligament ◽

Anterior Tibial Translation ◽

Tibial Rotation ◽

Femoral Antetorsion ◽

Anterior Drawer ◽

Tibial Translation ◽

Acl Deficient ◽

Deficient Knee

AbstractWe aimed to investigate how increased or decreased femoral antetorsion would affect the biomechanics of the knee in an anterior cruciate ligament (ACL)-deficient cadaveric model. We hypothesized that external or internal rotation of the distal femur, achieved through a femoral osteotomy, would affect the magnitude of tibiofemoral translation and rotation. Navigated measurements of tibiofemoral translation and rotation during the anterior drawer, Lachman, and pivot shift tests were performed on six whole-body cadaveric specimens in each of the following four conditions: native, ACL-deficient knee, ACL-deficient knee and 20-degree internal distal femur rotation, and ACL-deficient knee and 20-degree external distal femur rotation. Increased femoral antetorsion significantly reduced anterior tibial translation in the ACL-deficient knee during the anterior drawer, Lachman, and pivot shift tests (p < 0.05). Conversely, decreasing femoral antetorsion resulted in an increase in anterior tibial translation in the anterior drawer (nonsignificant), Lachman (p < 0.05), and pivot shift (p < 0.05) tests. Internally rotating the distal femur significantly reduced the magnitude of tibial rotation during the pivot shift test in the ACL-deficient knee (p < 0.05), whereas external rotation of the distal femur significantly increased tibial rotation (p < 0.05). The magnitude of femoral antetorsion affects tibiofemoral translation in an ACL-deficient cadaveric mode. Internally rotating the distal femur 20 degrees reduced the magnitude of tibial translation and rotation similar to that of the native knee, whereas externally rotating the distal femur aggravated translational and rotational instability.

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