scholarly journals Anterior Cruciate Ligament Graft Tunnel Placement and Graft Angle Are Primary Determinants of Internal Knee Mechanics After Reconstructive Surgery

2020 ◽  
Vol 48 (14) ◽  
pp. 3503-3514
Author(s):  
Michael F. Vignos ◽  
Colin R. Smith ◽  
Joshua D. Roth ◽  
Jarred M. Kaiser ◽  
Geoffrey S. Baer ◽  
...  
Keyword(s):  
Cruciate Ligament ◽  
Dynamic Mri ◽  
Knee Extension ◽  
Anterior Tibial Translation ◽  
Tunnel Placement ◽  
Acl Graft ◽  
Knee Mechanics ◽  
Graft Angle ◽  
Tibiofemoral Kinematics ◽  
Tibial Translation

Background: Graft placement is a modifiable and often discussed surgical factor in anterior cruciate ligament (ACL) reconstruction (ACLR). However, the sensitivity of functional knee mechanics to variability in graft placement is not well understood. Purpose: To (1) investigate the relationship of ACL graft tunnel location and graft angle with tibiofemoral kinematics in patients with ACLR, (2) compare experimentally measured relationships with those observed with a computational model to assess the predictive capabilities of the model, and (3) use the computational model to determine the effect of varying ACL graft tunnel placement on tibiofemoral joint mechanics during walking. Study Design: Controlled laboratory study. Methods: Eighteen participants who had undergone ACLR were tested. Bilateral ACL footprint location and graft angle were assessed using magnetic resonance imaging (MRI). Bilateral knee laxity was assessed at the completion of rehabilitation. Dynamic MRI was used to measure tibiofemoral kinematics and cartilage contact during active knee flexion-extension. Additionally, a total of 500 virtual ACLR models were created from a nominal computational knee model by varying ACL footprint locations, graft stiffness, and initial tension. Laxity tests, active knee extension, and walking were simulated with each virtual ACLR model. Linear regressions were performed between internal knee mechanics and ACL graft tunnel locations and angles for the patients with ACLR and the virtual ACLR models. Results: Static and dynamic MRI revealed that a more vertical graft in the sagittal plane was significantly related ( P < .05) to a greater laxity compliance index ( R2 = 0.40) and greater anterior tibial translation and internal tibial rotation during active knee extension ( R2 = 0.22 and 0.23, respectively). Similarly, knee extension simulations with the virtual ACLR models revealed that a more vertical graft led to greater laxity compliance index, anterior translation, and internal rotation ( R2 = 0.56, 0.26, and 0.13). These effects extended to simulations of walking, with a more vertical ACL graft inducing greater anterior tibial translation, ACL loading, and posterior migration of contact on the tibial plateaus. Conclusion: This study provides clinical evidence from patients who underwent ACLR and from complementary modeling that functional postoperative knee mechanics are sensitive to graft tunnel locations and graft angle. Of the factors studied, the sagittal angle of the ACL was particularly influential on knee mechanics. Clinical Relevance: Early-onset osteoarthritis from altered cartilage loading after ACLR is common. This study shows that postoperative cartilage loading is sensitive to graft angle. Therefore, variability in graft tunnel placement resulting in small deviations from the anatomic ACL angle might contribute to the elevated risk of osteoarthritis after ACLR.

Anterior Cruciate Ligament Graft Conditioning Required to Prevent an Abnormal Lachman and Pivot Shift After ACL Reconstruction: A Robotic Study of 3 ACL Graft Constructs

2019 ◽  
Vol 47 (6) ◽  
pp. 1376-1384 ◽  
Author(s):  
Frank R. Noyes ◽  
Lauren E. Huser ◽  
Brad Ashman ◽  
Michael Palmer
Keyword(s):  
Patellar Tendon ◽  
Pivot Shift ◽  
Cruciate Ligament ◽  
Anterior Tibial Translation ◽  
Acl Graft ◽  
Flexion Extension ◽  
Anterior Tibial ◽  
Tibial Translation ◽  
Bone Patellar Tendon ◽  
Anterior Posterior

Background: Anterior cruciate ligament (ACL) graft conditioning protocols to decrease postoperative increases in anterior tibial translation and pivot-shift instability have not been established. Purpose: To determine what ACL graft conditioning protocols should be performed at surgery to decrease postoperative graft elongation after ACL reconstruction. Study Design: Controlled laboratory study. Methods: A 6 degrees of freedom robotic simulator evaluated 3 ACL graft constructs in 7 cadaver knees for a total of 19 graft specimens. Knees were tested before and after ACL sectioning and after ACL graft conditioning protocols before reconstruction. The ACL grafts consisted of a 6-strand semitendinosus-gracilis TightRope, bone–patellar tendon–bone TightRope, and bone–patellar tendon–bone with interference screws. Two graft conditioning protocols were used: (1) graft board tensioning (20 minutes, 80 N) and (2) cyclic conditioning (5°-120° of flexion, 90-N anterior tibial load) after graft reconstruction to determine the number of cycles needed to obtain a steady state with no graft elongation. After conditioning, the grafts were cycled a second time under anterior-posterior loading (100 N, 25° of flexion) and under pivot-shift loading (100 N anterior, 5-N·m internal rotation, 7 N·m valgus) to verify that the ACL flexion-extension conditioning protocol was effective. Results: Graft board tensioning did not produce a steady-state graft. Major increases in anterior tibial translation occurred in the flexion-extension graft-loading protocol at 25° of flexion (mean ± SD: semitendinosus-gracilis TightRope, 3.4 ± 1.1 mm; bone–patellar tendon–bone TightRope, 3.2 ± 1.0 mm; bone–patellar tendon–bone with interference screws, 2.4 ± 1.5 mm). The second method of graft conditioning (40 cycles, 5°-120° of flexion, 90-N anterior load) produced a stable conditioned state for all grafts, as the anterior translations of the anterior-posterior and pivot-shift cycles were statistically equivalent ( P < .05, 1-20 cycles). Conclusion: ACL graft board conditioning protocols are not effective, leading to deleterious ACL graft elongations after reconstruction. A secondary ACL graft conditioning protocol of 40 flexion-extension cycles under 90-N graft loading was required for a well-conditioned graft, preventing further elongation and restoring normal anterior-posterior and pivot-shift translations. Clinical Relevance: There is a combined need for graft board tensioning and robust cyclic ACL graft loading before final graft fixation to restore knee stability.

Lateral Extra-articular Tenodesis Reduces Anterior Cruciate Ligament Graft Force and Anterior Tibial Translation in Response to Applied Pivoting and Anterior Drawer Loads

2020 ◽  
Vol 48 (13) ◽  
pp. 3183-3193
Author(s):  
Niv Marom ◽  
Hervé Ouanezar ◽  
Hamidreza Jahandar ◽  
Zaid A. Zayyad ◽  
Thomas Fraychineaud ◽  
...  
Keyword(s):  
Cruciate Ligament ◽  
Lateral Compartment ◽  
Anterior Tibial Translation ◽  
Anterior Drawer ◽  
Lachman Test ◽  
Acl Graft ◽  
Anterior Drawer Test ◽  
Anterior Laxity ◽  
Tibial Translation ◽  
Intact Knee

Background: The biomechanical effect of lateral extra-articular tenodesis (LET) performed in conjunction with anterior cruciate ligament (ACL) reconstruction (ACLR) on load sharing between the ACL graft and the LET and on knee kinematics is not clear. Purpose/Hypothesis: The purpose was to quantify the effect of LET on (1) forces carried by both the ACL graft and the LET and (2) tibiofemoral kinematics in response to simulated pivot shift and anterior laxity tests. We hypothesized that LET would decrease forces carried by the ACL graft and anterior tibial translation (ATT) in response to simulated pivoting maneuvers and during simulated tests of anterior laxity. Study Design: Controlled laboratory study. Methods: Seven cadaveric knees (mean age, 39 ± 12 years [range, 28-54 years]; 4 male) were mounted to a robotic manipulator. The robot simulated clinical pivoting maneuvers and tests of anterior laxity: namely, the Lachman and anterior drawer tests. Each knee was assessed in the following states: ACL intact, ACL sectioned, ACL reconstructed (using a bone–patellar tendon–bone autograft), and after performing LET (the modified Lemaire technique after sectioning of the anterolateral ligament and Kaplan fibers). Resultant forces carried by the ACL graft and LET at the peak applied loads were determined via superposition. ATT was determined in response to the applied loads. Results: With the applied pivoting loads, performing LET decreased ACL graft force up to 80% (44 ± 12 N; P < .001) and decreased ATT of the lateral compartment compared with that of the intact knee up to 7.6 ± 2.9 mm ( P < .001). The LET carried up to 91% of the force generated in the ACL graft during isolated ACLR (without LET). For simulated tests of anterior laxity, performing LET decreased ACL graft force by 70% (40 ± 20 N; P = .001) for the anterior drawer test with no significant difference detected for the Lachman test. No differences in ATT were deteced between ACLR with LET and the intact knee on both the Lachman and the anterior drawer tests ( P = .409). LET reduced ATT compared with isolated ACLR on the simulated anterior drawer test by 2.4 ± 1.8 mm ( P = .032) but not on the simulated Lachman test. Conclusion: In a cadaveric model, LET in combination with ACLR transferred loads from the ACL graft to the LET and reduced ATT with applied pivoting loads and during the simulated anterior drawer test. The effect of LET on ACL graft force and ATT was less pronounced on the simulated Lachman test. Clinical Relevance: LET in addition to ACLR may be a suitable option to offload the ACL graft and to reduce ATT in the lateral compartment to magnitudes less than that of the intact knee with clinical pivoting maneuvers. In contrast, LET did not offload the ACL graft or add to the anterior restraint provided by the ACL graft during the Lachman test.

In Vivo Joint Kinematics in Normal and Anterior Cruciate Ligament Injured Knees: Results of a Cine Phase Contrast Dynamic MRI Study

2003 ◽  
Author(s):  
Peter J. Barrance ◽  
Glenn N. Williams ◽  
Thomas S. Buchanan
Keyword(s):  
Anterior Cruciate Ligament ◽  
Phase Contrast ◽  
Cruciate Ligament ◽  
Dynamic Mri ◽  
Anterior Tibial Translation ◽  
Anterior Cruciate ◽  
Tibial Translation ◽  
Cine Phase Contrast ◽  
Acl Deficient

Cine phase contrast MRI, combined with a model-based rigid body tracking technique, was used to measure kinematics during a knee extension exercise in both knees of 16 anterior cruciate ligament (ACL) deficient surgical candidates and 16 uninjured subjects. A statistically significant increase in anterior tibial translation was observed in the ACL-deficient knees. Evidence of disruption to the screw-home mechanism was observed in the ACL-injured knees, although this was not a statistically significant result.

Analyses of Isokinetic and Closed Chain Movements for Hamstring Reciprocal Coactivation

2007 ◽  
Vol 16 (4) ◽  
pp. 319-325 ◽  
Author(s):  
John P. Miller ◽  
Ronald V. Croce
Keyword(s):  
Outcome Measures ◽  
High Speed ◽  
Cruciate Ligament ◽  
Knee Extension ◽  
Anterior Tibial Translation ◽  
Joint Stability ◽  
Closed Chain ◽  
Anterior Cruciate ◽  
The One ◽  
Tibial Translation

Context:Researchers have postulated that coactivation of the hamstrings during active knee extension assists the anterior cruciate ligament in maintaining knee joint stability by exerting an opposing force to anterior tibial translation.Objective:To compare the reciprocal coactivation of the hamstrings while performing low and high velocity isokinetic movements and two closed chain movements.Design:Within subject’s comparison of isokinetic and closed chain exercises.Setting:Biomechanics laboratory utilizing a Cybex norm isokinetic dynamometer and Biopac Data Collection system.Participants:12 healthy women.Main Outcome Measures:The root mean square of the Electromyogram (rmsEMG) was used as a measure of overall muscle activity.Results:The rmsEMG for hamstring coactivation during knee extension showed significant differences between the isokinetic movements and the closed chain exercises with greater coactivation when performing the isokinetic movements. In addition, greater activity was seen at the higher isokinetic velocity and during the one legged squat.Conclusions:These results suggest isokinetic movements, particularly at high speed, can more effectively increase the coactivation activity of the hamstrings when compared to two closed chain activities.

The Effect of Tunnel Placement on Bone-Tendon Healing in Anterior Cruciate Ligament Reconstruction in a Goat Model

2009 ◽  
Vol 37 (8) ◽  
pp. 1522-1530 ◽  
Author(s):  
Max Ekdahl ◽  
Masahiro Nozaki ◽  
Mario Ferretti ◽  
Andrew Tsai ◽  
Patrick Smolinski ◽  
...  
Keyword(s):  
Anterior Cruciate Ligament ◽  
Cruciate Ligament ◽  
Biomechanical Properties ◽  
Anterior Tibial Translation ◽  
Tunnel Placement ◽  
Anterior Tibial ◽  
Anterior Cruciate ◽  
Anterior Cruciate Ligament Surgery ◽  
Tibial Translation

Background Misplacement of the bone tunnels is one of the main causes of graft failure of anterior cruciate ligament surgery. Hypothesis Anatomic tunnel placement in anterior cruciate ligament surgery reconstruction will lead to improved outcomes, including biological ingrowth and biomechanical properties, when compared with nonanatomic tunnel placement. Study Design Controlled laboratory study. Methods Anterior cruciate ligament surgery reconstructions were performed on 3 different groups of goats (1 anatomic tunnel placement group and 2 different nonanatomic tunnel placement groups, with 10 goats in each group). For each group of 10 knees, 3 knees were used for histologic evaluation (bone tunnel enlargement, number of osteoclasts at the bone tendon interface, and revascularization of the graft) and 7 knees were used for biomechanical testing (anterior tibial translation, in situ force, cross-sectional area, and ultimate failure load). Animals were sacrificed at 12 weeks after surgery. Results The anatomic tunnel placement group showed less tunnel enlargement on the tibial side, fewer osteoclasts on both the tibial and femoral sides, and more vascularity in the femoral side when compared with the 2 nonanatomic reconstruction groups. Biomechanically, the anatomic tunnel placement group demonstrated less anterior tibial translation and greater in situ force than both nonanatomic tunnel placement groups. Conclusion Anatomic tunnel placement leads to superior biological healing and biomechanical properties compared with nonanatomic placement at 12 weeks after anterior cruciate ligament surgery reconstruction in a goat model. Clinical Relevance The findings of this study demonstrate the importance of anatomic tunnel placement in anterior cruciate ligament surgery reconstruction.

scholarly journals Copers and Noncopers Use Different Landing Techniques to Limit Anterior Tibial Translation After Anterior Cruciate Ligament Reconstruction

2021 ◽  
Vol 9 (4) ◽  
pp. 232596712199806
Author(s):  
Michèle N.J. Keizer ◽  
Egbert Otten ◽  
Chantal M.I. Beijersbergen ◽  
Reinoud W. Brouwer ◽  
Juha M. Hijmans
Keyword(s):  
Ligament Reconstruction ◽  
Cruciate Ligament ◽  
Anterior Tibial Translation ◽  
Return To Sports ◽  
Beighton Score ◽  
Positive Correlation ◽  
Anterior Tibial ◽  
Flexion Moment ◽  
Anterior Cruciate ◽  
Tibial Translation

Background: At 1 year after anterior cruciate ligament reconstruction (ACLR), two-thirds of patients manage to return to sports (copers), whereas one-third of patients do not return to sports (noncopers). Copers and noncopers have different muscle activation patterns, and noncopers may not be able to control dynamic anterior tibial translation (ATTd) as well as copers. Purpose/Hypothesis: To investigate whether (1) there is a positive correlation between passive ATT (ATTp; ie, general joint laxity) and ATTd during jump landing, (2) whether ATTd is moderated by muscle activating patterns, and (3) whether there is a difference in moderating ATTd between copers and noncopers. We hypothesized that patients who have undergone ACLR compensate for ATTd by developing muscle strategies that are more effective in copers compared with noncopers. Study Design: Controlled laboratory study. Methods: A total of 40 patients who underwent unilateral ACLR performed 10 single-leg hops for distance with both legs. Lower body kinematic and kinetic data were measured using a motion-capture system, and ATTd was determined with an embedded method. Muscle activity was measured using electromyographic signals. Bilateral ATTp was measured using a KT-1000 arthrometer. In addition, the Beighton score was obtained. Results: There was no significant correlation between ATTp and ATTd in copers; however, there was a positive correlation between ATTp and ATTd in the operated knee of noncopers. There was a positive correlation between the Beighton score and ATTp as well as between the Beighton score and ATTd in both copers and noncopers in the operated knee. Copers showed a negative correlation between ATTd and gastrocnemius activity in their operated leg during landing. Noncopers showed a positive correlation between ATTd and knee flexion moment in their operated knee during landing. Conclusion: Copers used increased gastrocnemius activity to reduce ATTd, whereas noncopers moderated ATTd by generating a smaller knee flexion moment. Clinical Relevance: This study showed that copers used different landing techniques than noncopers. Patients who returned to sports after ACLR had sufficient plantar flexor activation to limit ATTd.

Predictive Value of the Magnetic Resonance Imaging–Based Coronal Lateral Collateral Ligament Sign on Adolescent Anterior Cruciate Ligament Reconstruction Graft Failure

2021 ◽  
Vol 49 (4) ◽  
pp. 935-940
Author(s):  
Brendon C. Mitchell ◽  
Matthew Y. Siow ◽  
Tracey Bastrom ◽  
James D. Bomar ◽  
Andrew T. Pennock ◽  
...  
Keyword(s):  
Internal Rotation ◽  
Acl Reconstruction ◽  
Graft Failure ◽  
Cruciate Ligament ◽  
Lateral Collateral Ligament ◽  
Anterior Tibial Translation ◽  
Complex Injury ◽  
Patient Reported ◽  
Anterolateral Complex ◽  
Tibial Translation

Background: The coronal lateral collateral ligament (LCL) sign is the presence of the full length of the LCL visualized on a single coronal magnetic resonance imaging (MRI) slice at the posterolateral corner of the knee. The coronal LCL sign has been shown to be associated with elevated measures of anterior tibial translation and internal rotation in the setting of anterior cruciate ligament (ACL) tear. Hypothesis: The coronal LCL sign (with greater anterior translation, internal rotation, and posterior slope of the tibia) will indicate a greater risk for graft failure after ACL reconstructive surgery. Study Design: Cohort study; Level of evidence, 3. Methods: Retrospective review was performed of adolescent patients with ACL reconstruction: a cohort without graft failure and a cohort with graft failure. MRI was utilized to measure tibial translation and femorotibial rotation and to identify the coronal LCL sign. The posterior tibial slope was measured on lateral radiographs. Patient-reported outcomes were collected. Results: We identified 114 patients with no graft failure and 39 patients with graft failure who met all criteria, with a mean follow-up time of 3.5 years (range, 2-9.4 years). Anterior tibial translation was associated with anterolateral complex injury ( P < .001) but not graft failure ( P = .06). Internal tibial rotation was associated with anterolateral complex injury ( P < .001) and graft failure ( P = .042). Posterior tibial slope was associated with graft failure ( P = .044). The coronal LCL sign was associated with anterolateral complex injury ( P < .001) and graft failure ( P = .013), with an odds ratio of 4.3 for graft failure (95% CI, 1.6-11.6; P = .003). Subjective patient-reported outcomes and return to previous level of sport were not associated with failure. Comparison of MRI before and after ACL reconstruction in the graft failure cohort demonstrated a reduced value in internal rotation ( P = .003) but no change in coronal LCL sign ( P = .922). Conclusion: Our study demonstrates that tibial internal rotation and posterior slope are independent predictors of ACL graft failure in adolescents. Although the value of internal rotation could be improved with ACL reconstruction, the presence of the coronal LCL sign persisted over time and was predictive of graft rupture (without the need to make measurements or memorize values of significant risk). Together, these factors indicate that greater initial knee deformity after initial ACL tear predicts greater risk for future graft failure.

scholarly journals Computer-Assisted System in Stress Radiography for Anterior Cruciate Ligament Injury with Correspondent Evaluation of Relevant Diagnostic Factors

Diagnostics ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 419
Author(s):  
Chien-Kuo Wang ◽  
Liang-Ching Lin ◽  
Yung-Nien Sun ◽  
Cheng-Shih Lai ◽  
Chia-Hui Chen ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Cruciate Ligament ◽  
Anterior Tibial Translation ◽  
Computer Assisted ◽  
Time Interval ◽  
Stress Radiography ◽  
Factors Affecting ◽  
Anterior Tibial ◽  
Anterior Cruciate ◽  
Tibial Translation

We sought to design a computer-assisted system measuring the anterior tibial translation in stress radiography, evaluate its diagnostic performance for an anterior cruciate ligament (ACL) tear, and assess factors affecting the diagnostic accuracy. Retrospective research for patients with both knee stress radiography and magnetic resonance imaging (MRI) at our institution was performed. A complete ACL rupture was confirmed on an MRI. The anterior tibial translations with four different methods were measured in 249 patients by the designed algorithm. The diagnostic accuracy of each method in patients with all successful measurements was evaluated. Univariate logistic regression analysis for factors affecting diagnostic accuracy of method four was performed. In the inclusive 249 patients, 177 patients (129 with completely torn ACLs) were available for analysis. Mean anterior tibial translations were significantly increased in the patients with a completely torn ACL by all four methods, with diagnostic accuracies ranging from 66.7% to 75.1%. The diagnostic accuracy of method four was negatively associated with the time interval between stress radiography and MRI as well as force-joint distance on stress view, and not significantly associated with age, gender, flexion angle, intercondylar distance, and force-joint angle. A computer-assisted system measuring the anterior tibial translation in stress radiography showed acceptable diagnostic performance of complete ACL injury. A shorter time interval between stress radiography and MRI as well as shorter force-joint distance were associated with higher diagnostic accuracy.

scholarly journals Seeing Beyond Morphology-Standardized Stress MRI to Assess Human Knee Joint Instability

Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1035
Author(s):  
Eva-Maria Winkelmeyer ◽  
Justus Schock ◽  
Lena Marie Wollschläger ◽  
Philipp Schad ◽  
Marc Sebastian Huppertz ◽  
...  
Keyword(s):  
Knee Joint ◽  
Imaging Modality ◽  
Cruciate Ligament ◽  
Acl Injury ◽  
Anterior Tibial Translation ◽  
Joint Stability ◽  
Anatomic Landmarks ◽  
Human Knee Joint ◽  
Custom Made ◽  
Tibial Translation

While providing the reference imaging modality for joint pathologies, MRI is focused on morphology and static configurations, thereby not fully exploiting the modality’s diagnostic capabilities. This study aimed to assess the diagnostic value of stress MRI combining imaging and loading in differentiating partial versus complete anterior cruciate ligament (ACL)-injury. Ten human cadaveric knee joint specimens were subjected to serial imaging using a 3.0T MRI scanner and a custom-made pressure-controlled loading device. Emulating the anterior-drawer test, joints were imaged before and after arthroscopic partial and complete ACL transection in the unloaded and loaded configurations using morphologic sequences. Following manual segmentations and registration of anatomic landmarks, two 3D vectors were computed between anatomic landmarks and registered coordinates. Loading-induced changes were quantified as vector lengths, angles, and projections on the x-, y-, and z-axis, related to the intact unloaded configuration, and referenced to manual measurements. Vector lengths and projections significantly increased with loading and increasing ACL injury and indicated multidimensional changes. Manual measurements confirmed gradually increasing anterior tibial translation. Beyond imaging of ligament structure and functionality, stress MRI techniques can quantify joint stability to differentiate partial and complete ACL injury and, possibly, compare surgical procedures and monitor treatment outcomes.

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