Research on surgical strategies to minimize tunnel collisions in combined anterior cruciate ligament (ACL) reconstruction (ACLR) using the modified transtibial technique (MTT) and anterolateral augmentation is limited, unlike with independent tunnel drilling techniques. To analyze the optimal drill orientations for the anterolateral ligament (ALL) femoral tunnel to minimize tunnel collisions and reduce damage to surrounding structures during combined ACLR with MTT and anterolateral augmentation procedures, accounting for far-cortex drilling (FCD) of the ALL femoral tunnel required for graft fixation. Descriptive laboratory study. Three-dimensional reconstructed femoral models of patients who underwent ACLR with MTT between 2015 and 2018 were used. Geometric factors of femoral models were analyzed, and virtual ALL femoral tunnels were simulated to evaluate 45 drilling combinations. To assess potential damage to surrounding structures associated with ALL femoral tunnel drilling, femoral cortical violation caused by the ALL femoral tunnel itself was assessed under each drilling condition, whereas tunnel trajectories were analyzed to classify drilling conditions according to FCD. In addition, the minimum distance between the ACL and ALL femoral tunnels (MDBT) and the tunnel collision rate were evaluated. A total of 27 patients were analyzed. In scenarios where FCD was not required for ALL graft femoral fixation, the optimal drill orientation for the ALL femoral tunnel was within the range of coronal -40° to -20°, eliminating cortex violation and tunnel collisions (mean MDBT, 9 ± 4.1 mm; collision rate 0%). When FCD was required for ALL graft femoral fixation, the optimal drill orientation was axial 40° and coronal 10°, resulting in the longest MDBT without the risk of femoral cortex violation (MDBT, 4.9 ± 3.5 mm; collision rate, 7.4%). During the combined surgeries for ACLR using MTT and anterolateral augmentation procedures, the optimal drill orientation of the ALL femoral tunnel was within the range of coronal -40° to -20° for techniques not requiring FCD and axial 40° and coronal 10° for those requiring FCD. This study provides practical surgical guidance for optimizing ALL femoral tunnel orientation during combined ACLR using MTT and anterolateral augmentation. By accounting for whether FCD is required for ALL graft femoral fixation, the findings may help surgeons minimize tunnel collision and reduce the risk of femoral cortical violation, thereby potentially decreasing procedure-related complications.

BackgroundResidual laxity after anterior cruciate ligament reconstruction (ACL-R) is found in some cases. Nowadays, anterolateral augmentation procedures are performed to prevent this laxity.Materials and methods A prospective randomized comparative clinical study took place from January 2021 to November 2022. The study included 48 patients after exclusion of losses to follow-up, who acquired ACL-R combined with either lateral extraarticular tenodesis (LET) in 25 or anterolateral reconstruction (ALL) in 23 patients. The patients were evaluated with the Tegner-Lysholm score, and follow-up was for 26 ± 7 months. Also, laxity tests, pivot shift and Lachman preoperatively and postoperatively were evaluated. The failure rate was assessed.ResultsTegner-Lysholm score improved significantly from 51.28 preoperatively to 93.76 points two years postoperatively in the LET-group and from 54.55 preoperatively to 94.23 points two years postoperatively in the ALL-group (P-value < 0.0001 in both groups). There was no significant difference between values of the Tegner-Lysholm score for the two groups at two-year follow-up (P-value = 0.24). Also, there was a significant reduction in the number of patients with positive pivot shift and Lachman tests in each group (P value < 0.0001 in both groups). The failure rate was 8% for LET and 8.7% for ALL (P-value = 0.46). Revisions were done from the contralateral side within the follow-up period.ConclusionsThe clinical outcome and stability after anterior cruciate ligament reconstruction combined with either lateral extraarticular tenodesis or anterolateral ligament reconstruction improved significantly after two years. However, no significant difference between them was found after two years. Both groups had comparable failure rates. However, the intraoperative and postoperative findings support anterolateral ligament reconstruction.Level of evidenceLevel 1, prospective randomized comparative study.Trial registrationClinical trial registry: NCT06222814. Registered at 01/01/2024, retrospectively.Key pointsComparative study between extraaricular tenodesis and anterolateral reconstruction combined with ACL-R., Clinical outcome after ACL reconstruction combination. Anterolateral Ligament Reconstruction or extraaricular tenodesis, rotatory and anterior laxity knee, lateral stabilization of the knee.

This systematic review aimed to determine the statistical fragility of randomized controlled trials (RCTs) comparing anterior cruciate ligament reconstruction (ACLR) with or without anterolateral complex (ALC) procedures. PubMed, MEDLINE, and EMBASE were searched from inception to April 22, 2024 for RCTs comparing ACLR with or without ALC procedures (lateral extra-articular tenodesis or anterolateral ligament reconstruction). Studies that reported≥1 statistically significant continuous outcome, statistically significant dichotomous outcome, and/or non-significant dichotomous outcome were included. The fragility index (FI), continuous fragility index (CFI), and reverse fragility index (RFI) were calculated for these outcomes, respectively. 20 RCTs including 2,292 patients were included (mean study size: 114.6 patients). The median FI across 21 outcomes from 11 studies was 2.0 (interquartile range [IQR], 2.0). The median CFI across 20 outcomes from seven studies was 16.9 (IQR, 227.7). The median RFI across 107 outcomes from 19 studies was 5.0 (IQR, 2.0). The number of patients lost to follow-up at the final follow-up period was more than the study-specific FI in eight (72.7%) studies, CFI in two (28.6%) studies, and RFI in 12 (63.2%) studies. This systematic review demonstrated that RCTs comparing ACLR with or without ALC procedures have low FI and RFI values that tended to exceed loss to follow-up, demonstrating relative statistical fragility of existing literature. However, CFI values were high amongst RCTs, suggesting robustness in findings for quantitative outcomes. While fragility indices are important metrics of robustness to consider, their application in research and clinical practice should be further investigated.

We biomechanically compared three anterolateral procedures (artificial-anterolateral ligament [ALL] reconstruction, autologous-ALL reconstruction and lateral extra-articular tenodesis [LET]) in knees with anterior cruciate ligament (ACL) and anterolateral complex (ALC) injuries when combined with nonanatomic artificial ACL reconstruction. Eight cadaveric knees were tested robotically at time-zero: (1) intact, (2) ACL + ALC deficient, (3) ACL reconstruction + artificial-ALL reconstruction, (4) ACL reconstruction + autologous-ALL reconstruction, (5) ACL reconstruction+LET. Each state was tested under 3 loads: (1) a 89N anterior tibial (AT) loading to test AT translation (ATT) at full extension (FE), 30°, 60° and 90°, (2) a 5N·m internal rotation (IR) tibial torque to test tibial IR at FE, 15°, 30° and 45°, (3) a simulated pivot-shift test consisting of a combined 5 N·m IR tibial torque and 7 N·m valgus load to test ATT and IR at FE, 15°, 30° and 45°. ACL + ALC deficiency impaired anteroposterior and rotational knee stability across all conditions. Under 89 N AT loading, the anterior instability was fully restored by ACL reconstruction + artificial-ALL reconstruction (n.s.) and partially by ACL reconstruction + autologous-ALL reconstruction and ACL reconstruction + LET, with significant differences from the intact state at 30° (p = 0.019) and 60° (p = 0.011) in the ACL reconstruction + autologous-ALL reconstruction state and at 30° (p = 0.032) and 60° (p = 0.018) in the ACL reconstruction+LET state. Under 5 N·m IR tibial torque, the internal rotational instability was fully restored by ACL reconstruction+artificial-ALL reconstruction and ACL reconstruction + LET (n.s.) and partially by ACL reconstruction + autologous-ALL reconstruction, with significant differences from the intact state at FE (p = 0.044) and 15° (p = 0.049). During simulated pivot-shift testing, all three procedures fully restored native kinematics with no significant differences observed (n.s.). Artificial-ALL reconstruction, autologous-ALL reconstruction, and LET similarly restored native knee kinematics in ACL + ALC deficient knees when combined with artificial ACL reconstruction at time-zero. Level V, laboratory study.

Spin is a form of bias that misrepresents research findings, potentially influencing clinical decisions and patient care. This meta-research study evaluates the prevalence and types of spin in abstracts of systematic reviews and meta-analyses comparing anterior cruciate ligament reconstruction (ACLR) with and without lateral extra-articular tenodesis (LET) and anterolateral ligament reconstruction (ALLR). A secondary aim is to assess review quality per AMSTAR-2 criteria and associations between spin and review characteristics. A systematic search of PubMed, EMBASE and MEDLINE[Ovid] in May 2024 identified eligible reviews. Two reviewers independently assessed the nine most severe types of spin and methodological quality using AMSTAR-2. Review characteristics, including publication year, total citations, average yearly citations and journal impact factor, were analyzed for associations with spin. Of 24 included reviews, 75% (18/24) contained at least one form of spin, with Type 3 spin, 'Selective reporting or overemphasis on efficacy outcomes favoring the experimental intervention', being the most common (62.5%, 15/24). Reviews with spin had a significantly more recent median publication year (p = 0.011), while those without spin had significantly higher total citation counts (p = 0.021). No significant differences were observed in average yearly citations or impact factors between groups. Reviews with three or more types of spin were published more recently than those with fewer (p = 0.007), with no significant differences in total citations, average yearly citations or impact factor. Most reviews (91.7%) were rated as critically low-quality using AMSTAR-2, with substantial inter-reviewer agreement (κ = 0.839). Spin is highly prevalent in systematic reviews and meta-analyses evaluating ACLR with and without LET or ALLR, particularly in recent publications. Given that many reviews exhibit critically low methodological quality, efforts should focus on strengthening adherence to reporting standards and reducing spin to ensure the publication of unbiased evidence that informs clinical practice. Level IV.

Anatomical knowledge and identification of multiple ligament knee injuries have considerably evolved during the last decade. Consecutively, a trend for anatomical reconstruction of these injuries emerged. These procedures are challenging and require precise planning. Moreover, the planning itself is made difficult by the variety of techniques, whose descriptions are scattered throughout the literature. The objective is to reference and categorize the different ligament reconstruction techniques to provide free planning assistance software using a standardized graphic chart.The search for ligament reconstruction techniques on nine different databases produced 1,536 articles. After reviewing for relevance, the authors included the full papers of the remaining 306 articles. From the reference lists of the selected articles reviewed, 96 studies describing original techniques were retrieved. Techniques were extracted, drawn following the same graphics chart, and classified into conceptual categories.After selection, 10, 4, 28, 28, and 26 articles described anterior cruciate ligament, posterior cruciate ligament, posteromedial corner, posterolateral corner, and anterolateral corner procedures for reconstruction, respectively. Early techniques often used tenodesis while nowadays various grafts are fixed to isometric points or anatomic landmarks. An interactive tool was created. It allows the visualization of selected reconstructions on axial, frontal, and sagittal representations of the knee. Tunnel position, preferred transplant type, and fixation mode are represented. The freeware is available at: https://apps.medecine.u-paris.fr/multilig/.The techniques described for the reconstruction of an isolated ligament or corner cannot always be extrapolated for multiple ligament knee injuries treatment. Bone stock and tunnel convergence are two main concerns to consider during planning. Sometimes, it could be necessary to sacrifice a potentially biomechanically superior approach if simpler reconstructions provide equivalent knee kinematics. Surgical options are multiple and scattered throughout the literature. Our study provides an open-source and clinician-accessible research tool for multiple ligament injuries planification using a standardized graphic chart.

Knee Fellowships Improve Clinical Practice and Scientific Activity

BackgroundKnee proprioception may be compromised after anterior cruciate ligament reconstruction (ACLR), but associated factors and impact remain unclear. This study evaluated knee proprioception 4 months after primary ACLR, compared with healthy controls, and explored the impacts of leg dominance, anterolateral procedures (AEAPs), and their association with psychological readiness to return to sports. MethodsThis prospective cohort study included 30 ACLR participants and 20 healthy controls. Isokinetic testing measured knee strength and proprioception, using passive joint position sense (JPS1: detection, JPS2: repositioning) and kinesthesia (threshold to detection of passive motion). At 8 months, ACLR participants completed the ACL-RSI scale to assess psychological readiness to return to sports. ResultsAt 4 months postoperative, kinesthesia was better in the operated limb than the non-operated limb (p= 0.008), but position sense did not differ significantly. There were no significant differences in kinesthesia or position sense between ACLR participants and controls. The operated limb had worse JPS2 if the ACLR was on the non-dominant side. Proprioception was unaffected by AEAPs, and only repositioning showed a moderate, non-significant correlation with ACL-RSI (r= -0.377). ConclusionAt 4 months post-ACLR, kinesthesia improved in the operated leg; dominance influenced position sense, highlighting the need for personalized rehabilitation.

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Dr. Bertrand Sonnery-Cottet’s trajectory from a childhood in a foster home to the presidency of the French Arthroscopy Society reflects a career defined by clinical rigor. Specializing in knee ligament reconstruction, he pioneered the modern application of anterolateral ligament procedures. His commitment to data-driven research and the integration of mixed reality into the operating room underscores a focus on reducing surgical failure. This interview explores his transition from traditional mentorship to digital innovation in sports surgery.

Background: The incidence of anterior cruciate ligament (ACL) tears in pediatric and adolescent populations has increased significantly, rising approximately 2.3% annually. Management remains controversial due to the competing risks of secondary meniscal or chondral degeneration from knee instability versus potential growth disturbances following surgical reconstruction in skeletally immature patients. Objective: This article aims to define the clinical indications for surgical intervention and clarify the contemporary role of conservative management in growing children with ACL injuries. Key Points: Initial assessment requires differentiating physiological joint laxity from symptomatic instability and utilizing MRI to identify concomitant meniscal pathology, despite lower diagnostic specificity in younger children. Conservative management, involving a three-phase neuromuscular rehabilitation protocol, may be appropriate for patients under 12 years (Tanner stage 1) who exhibit perfect stability and no associated lesions. However, longitudinal data indicate that up to 57% of non-operative patients eventually require reconstruction due to secondary instability or meniscal tears. Surgical techniques, categorized as all-epiphyseal or transphyseal, must prioritize tendon grafts, small-diameter tunnels, and physeal-sparing fixation. While reconstruction facilitates a high rate of return to sport (approximately 80–93%), complications include a 4–8.7% risk of growth disturbances and high rates of graft rupture or contralateral injury. Conclusion: Pediatric ACL management requires individualized strategies based on skeletal maturity and clinical stability. While conservative protocols are viable for select stable patients, surgical reconstruction is indicated for persistent instability or associated meniscal tears to prevent long-term degenerative changes. Combined anterolateral procedures and delayed return to sport may mitigate high graft failure rates.

Combined Anterior Cruciate Ligament Reconstruction, Posterolateral Corner Reconstruction, and Lateral Extra-Articular Tenodesis

BACKGROUND: The anterior cruciate ligament (ACL) is one of two primary ligaments responsible for providing stability to the knee joint. ACL rupture is a frequent occurrence in sports-related knee injuries. Persistent rotational instability following surgical reconstruction of the anterior cruciate ligament (ACLR) has presented a longstanding difficulty. Anterolateral extra-articular procedures (AEAP), including lateral extra-articular tenodesis (LET) or reconstruction of the anterolateral ligament (ALLR), have been employed to address this issue. METHODS: In this systematic review and meta-analysis, PubMed, ScienceDirect, and Cochrane databases were searched from inception to August 2023. Randomized Controlled Trials (RCTs) studies were included. The CONSORT criteria were used to assess the risk of bias. Using Review Manager ver. 5.4. The effect sizes were estimated as log risk ratios and SMDs with 95% confidence intervals (CIs). RESULTS: Of the 17 screened studies, 9 RCTs met the eligibility criteria for qualitative analysis; 7 were included in the meta-analysis. It was found that [OR = -1.56 (-2.02 to -1.06), P &lt; 0.001)] in favor of ACLR+AEAP, this indicates that the incorporation of AEAP in ACLR leads to significantly improved pivot shift test results, thereby enhancing rotational stability. The comparison of pivot-shift alone in LET [OR = 0.40 (0.19-0.81), P &lt; 0.0001] and ALLR [OR = 0.23 (0.11-0.47), P &lt; 0.0001]. The comparison of adverse event rates in LET [OR = 2.34 (1.53-3.58), P &lt; 0.0001] and ALLR [OR = 0.59 (0.36-0.95), P = 0.03]. CONCLUSIONS: This meta-analysis has found that use of either LET or ALLR in addition to ACLR enhances mechanical results. Patients who received both additional procedures along with ACLR exhibited better pivot-shift grades than those who only had ACLR. Moreover, both combined approaches resulted in lower rates of ACL re-rupture compared to ACLR alone. Notably, ALLR also led to lower rates of ACL re-rupture compared to LET.

Anterior cruciate ligament reconstruction (ACLR) failures occur for various reasons including residual laxity, untreated concomitant injuries, poor graft quality, and high tibial slope. Various additional procedures can help to decrease revision ACLR failures including anterolateral complex (ALC) procedures and slope-reducing osteotomies for patients with high tibial slopes. This narrative review aims to review the literature on the roles of ALC augmentation procedures and slope-reducing osteotomies in the setting of patients undergoing revision ACLRs. A narrative review of relevant literature was performed in July 2024. Studies about anterolateral complex reconstructions and slope-reducing osteotomies in revision ACLRs were included. The literature reported that lateral extra-articular tenodesis (LET) and anterolateral ligament reconstructions (ALLR) can be used in revision ACLR cases to significantly reduce clinical knee laxity and the risk of repeated graft failure. There is not currently a strong opinion on which ALC procedure is superior. There are reported slight differences in lateral knee pain and knee stiffness, but both similarly significantly improve clinical and functional outcomes. In revision ACLR cases that also have a high posterior tibial slope (PTS), a slope-reducing tibial osteotomy is warranted. An anterior closing wedge proximal tibial osteotomy (ACW-PTO) significantly reduces anterior tibial translation and graft failure. There is concern about the changes to patellar height, but the literature has found that such changes are either slight or absent by 6 months postoperatively. The risk of ACLR failure is increased by risk factors like high tibial slope, preoperative knee laxity, and prior ACLR rupture. Anterolateral complex procedures and slope-reducing osteotomies may be used to address these specific concerns and reduce the risk of graft rupture. For revision ACLR cases with lower PTS, augmentation with a LET or an ALLR to reduce the risk of graft failure and improve rotational stability may be warranted. In the setting of a revision ACLR in patients with a high PTS of ≥12°, a concomitant ACW-PTO and ALC procedure should be considered to decrease the risk of an ACLR graft failure.

IntroductionAnterior 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.MethodsInternal 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.ResultsThe 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.ConclusionThis 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.

Several anterolateral stabilization procedures have been developed recently to address rotational instability of the knee. Currently, these procedures tend to be systematically used by some practitioners. However, antero-lateral structures of the knee (including the anterolateral ligament, ALL) have a self-healing potential which can reduce the need to perform an antero-lateral procedure. In this study, it was hypothesized that early post-traumatic immobilization of the knee with a knee brace would allow partial healing of antero-lateral structures and also allow control of the pivot shift, thus avoiding antero-lateral extra-articular stabilization. The objective of this study was to compare the severity of pivot shift between two groups of patients who all experienced anterior cruciate ligament (ACL) tear and respectively underwent post-traumatic immobilization of the knee versus no immobilization. This was a comparative, multicentric (three centers' study) retrospective, consecutive study including 168 patients who underwent ACL reconstruction between May and September 2022. The application or not of post-traumatic immobilization and its duration, the severity of pivot shift observed in the operating room under general anesthesia, the presence of anterolateral lesions as revealed by MRI and the patients' pre-injury sport activity were recorded. A grade 3 pivot shift was found in 44 patients (27%). It was more frequently observed in the group without a brace compared to the group with a knee brace (18 patients out of 36: 50% versus 26 patients out of 132: 19.7%; p = 0.0012). Wearing a brace, whether hinged (OR = 0.221, [0.070-0.652]; p = 0.006) or not (OR = 0.232, [0.076-0.667]; p = 0.0064), was protective from the risk of developing a significant pivot shift. This study demonstrated that the presence of pivot-shift was lower in the patients that had an early post-injury knee brace before their ACL reconstruction. Based on this result, systematic brace placement could be advocated for in patients after knee trauma. III, prognostic retrospective case-control study.

Graft failure rates after anterior cruciate ligament reconstruction (ACLR) in children and adolescents are higher compared to adults. Anterolateral augmentation procedures have recently generated increased focus regarding their ability to reduce graft failure rates. Concerns in skeletally immatures are potential growth disturbances and overconstraint after anterolateral augmentation. The aim of this scoping review is to provide an overview of all current anterolateral augmentation procedures in skeletally immature patients and to discuss surgical techniques, clinical and biomechanical outcomes. This scoping review was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) statement extension for scoping reviews. On 22December 2022, an information specialist performed a systematic literature search in Cochrane, PubMed (Medline) and EMBASE databases. Inclusion criteria were anterolateral augmentation procedures, including lateral extra-articular tenodesis (LET) and anterolateral ligament reconstruction (ALLR), in combination with ACLR in skeletally immatures. Twenty studies were included after screening 1.485 abstracts. Seventeen studies describe LET techniques, four studies ALLR techniques and one study both techniques. Biomechanical data is scarce and shows conflicting results. Two studies compared ACLR with LET to ACLR in skeletally immatures with promising results in favour of the combined procedure. There were no differences in outcomes between LET and ALLR. Several LET and ALLR techniques have been described for skeletally immature patients and the first clinical data on LET and ALLR is available, which showed promising results. Further research is necessary to evaluate the risk of growth disturbances and overconstraint in skeletally immatures. Level IV.

Objective To evaluate the incidence of symptomatic cyclops lesions requiring surgical treatment after anterior cruciate ligament (ACL) reconstruction and to establish possible intraoperative risk factors related to it. Methods Three hundred and eighty-nine patients aged between 18 and 50 years who underwent primary ACL reconstruction were retrospectively evaluated. Patients were divided into groups according to the presence or absence of symptomatic cyclops lesions, and their characteristics were compared. Patients with associated lesions that required additional surgical procedures (except anterolateral extra-articular procedures) were not included. The rate of symptomatic cyclops lesions was recorded and the following parameters were evaluated: age, gender, time from injury to surgery, graft type and diameter, femoral tunnel perforation technique, fixation type, presence of knee hyperextension, preservation of the ACL remnant, associated anterolateral extra-articular procedure, associated meniscal injury and participation in sports. Results 389 patients were evaluated and 26 (6.7%) patients developed cyclops. The patients with and without cyclops lesions did not differ in age, time from injury to surgery, graft type or diameter, surgical technique, femoral fixation method, presence of knee hyperextension, remnant preservation and associated meniscal injury. The group with cyclops lesion had a higher proportion of females (10 (38.4%) vs 68 (18.7%); OR = 2.7; p = 0.015), higher proportion of extra-articular reconstruction (18 (11.8%) vs 8 (3.4%); OR = 3.8; p = 0.001) and higher proportion of sports practice (23 (8.6%) vs 3 (2.5%); OR = 3.6; p = 0.026). Conclusion In our series, 6.7% of the patients required arthroscopic removal of cyclops lesions. Female gender, associated extra-articular reconstruction and sports practice were factors related to this lesion. Remnant preservation had no relationship with cyclops lesion formation.

BackgroundIsolated ACL reconstructions (ACLR) demonstrate limitations in restoring native knee kinematics. This study investigates the knee mechanics of ACLR plus various anterolateral augmentations using a patient-specific musculoskeletal knee model.Materials and methodsA patient-specific knee model was developed in OpenSim using contact surfaces and ligament details derived from MRI and CT data. The contact geometry and ligament parameters were varied until the predicted knee angles for intact and ACL-sectioned models were validated against cadaveric test data for that same specimen. Musculoskeletal models of the ACLR combined with various anterolateral augmentations were then simulated. Knee angles were compared between these reconstruction models to determine which technique best matched the intact kinematics. Also, ligament strains calculated by the validated knee model were compared to those of the OpenSim model driven by experimental data. The accuracy of the results was assessed by calculating the normalised RMS error (NRMSE); an NRMSE < 30% was considered acceptable.ResultsAll rotations and translations predicted by the knee model were acceptable when compared to the cadaveric data (NRMSE < 30%), except for the anterior/posterior translation (NRMSE > 60%). Similar errors were observed between ACL strain results (NRMSE > 60%). Other ligament comparisons were acceptable. All ACLR plus anterolateral augmentation models restored kinematics toward the intact state, with ACLR plus anterolateral ligament reconstruction (ACLR + ALLR) achieving the best match and the greatest strain reduction in ACL, PCL, MCL, and DMCL.ConclusionThe intact and ACL-sectioned models were validated against cadaveric experimental results for all rotations. It is acknowledged that the validation criteria are very lenient; further refinement is required for improved validation. The results indicate that anterolateral augmentation moves the kinematics closer to the intact knee state; combined ACLR and ALLR provide the best outcome for this specimen.

Background: There is growing evidence that anterolateral procedures can reduce the risk of rerupture in high-risk recreational athletes undergoing primary anterior cruciate ligament (ACL) reconstruction (ACLR). However, this effectiveness has never been evaluated in elite athletes. Purpose: The purpose of this study was to evaluate the effectiveness of lateral extra-articular tenodesis (LET) in reducing revision rates in primary ACLR in elite athletes. Additionally, this study evaluated whether LET had a greater effect when combined with ACLR utilizing a hamstring or patellar tendon graft. Study Design: Cohort study; Level of evidence, 3. Methods: A consecutive cohort of elite athletes with an isolated ACL tear undergoing autograft patellar or hamstring tendon reconstruction with or without Lemaire LET were analyzed between 2005 and 2018. A minimum 2-year follow-up was required. The association between the use of LET and ACL graft failure as defined by revision ACLR was evaluated with univariate and multivariate logistic regression models. Results: A total of 455 elite athletes (83% men and overall age 22.5 ± 4.7 years) underwent primary ACLR with (n = 117) or without (n = 338) a LET procedure. Overall, 36 athletes (7.9%) experienced ACL graft failure, including 32 (9.5%) reconstructions without a LET and 4 (3.4%) with a LET. Utilization of LET during primary ACLR reduced the risk of graft failure by 2.8 times, with 16.5 athletes needing LET to prevent a single ACL graft failure. Multivariate models showed that LET significantly reduced the risk of graft rupture (relative risk = 0.325; P = .029) as compared with ACLR alone after controlling for sex and age at ACLR. Including graft type in the model did not significantly change the risk profile, and although a patellar tendon graft had a slightly lower risk of failure, this was not statistically significant (P = .466). Conclusion: The addition of LET reduced the risk of undergoing revision by 2.8 times in elite athletes undergoing primary ACLR. This risk reduction did not differ significantly between the patellar tendon and hamstring tendon autografts. With these results, status as an elite athlete should be included in the indications for a LET, as they are at increased risk for ACL graft failure.