Longitudinal tear of the medial meniscus posterior horn in the anterior cruciate ligament-deficient knee significantly influences anterior stability

In the Acute Phase of Anterior Cruciate Ligament Rupture: Quantitative Assessment of Matrix Changes and Correlation between Different States of Meniscus and Adjacent Cartilage

OBJECTIVE

Cartilage and meniscus are important structures that maintain the health of the knee joint. Early detection of changes in the internal components of cartilage and meniscus before morphological changes occur is essential to prevent and delay the development of osteoarthritis (OA). This study was designed to determine the changes in the matrix composition of morphologically intact cartilage and meniscus during the acute phase of an anterior cruciate ligament (ACL) rupture, as well as the effect of different states of meniscus (intact or tear) on adjacent cartilage during the acute phase.

METHODS

This cross-sectional study compared and analyzed 50 patients in the acute phase of ACL rupture who underwent surgical treatment and 66 age-, weight- and height-matched healthy volunteers from May 2022 to May 2023 at our institution. Mean T2 relaxation times and effect sizes in different regions of tibiofemoral articular cartilage and meniscus were compared between the two groups using the Mann-Whitney nonparametric t-test, and correlations between different meniscal states and adjacent cartilage were analyzed.

RESULTS

Both in the lateral and medial compartments of the knee, T2 relaxation times were significantly higher in all subregions of cartilage and meniscus in the ACL rupture group (p < 0.05), and the site of injury was predominantly centered in the medial compartment (femur, p = 0.000; tibia, p = 0.000; anterior horn, p = 0.000). In the respective compartments, the posterior horn of the lateral meniscus showed a significant positive correlation with the mid-cartilage of the femoral and tibial (r = 0.566, p = 0.035; r = 0.611, p = 0.02); and the posterior horn of the medial meniscus showed a significant positive correlation with the posterior tibial cartilage (r = 0.668, p = 0.018).

CONCLUSION

During the acute phase of ACL rupture, the internal composition of the cartilage and meniscus undergoes significant changes, even if the morphology is intact. More importantly, the state of the meniscus significantly affects the internal composition of the adjacent cartilage. This is an early warning sign of OA, which should be closely monitored and carefully managed in clinical practice.

All the menisco-ligamentary structures of the medial plane play a significant role in controlling anterior tibial translation and tibial rotation of the knee. Cadaveric study of 29 knees with the Dyneelax® laximeter

Purpose

This study aimed to determine the respective roles of the anterior cruciate ligament (ACL) and the different components of the medial plane in the control of anterior tibial translation and internal and external tibial rotation.

Methods

Twenty-nine fresh lower limbs, disarticulated at the hip, were tested in the anatomy laboratory. The following structures were isolated: the ACL, the anteromedial retinaculum (AMR), the medial collateral ligament (superficial and deep MCL), the posterior medial capsule (PMC) and the posterior horn of the medial meniscus (PHMM). The lower limb was positioned at 30° of flexion on the Dyneelax® laximeter (0.1 mm and 0.1° accuracies) and underwent anterior loads up to 200 N and internal and external tibial rotations sectioned from front to back. and the knee was then retested. The results were presented as relative gains in translation and rotations for each structure. Student's t test and Wilcoxon tests were used.

Results

The relative gains in translation for the ACL, AMR, superficial MCL, deep MCL, PMC and PHMM, respectively, were 42.9%, 6.7%, 7.4%, 6%, 7.5% and 11.6%. The relative gains in internal rotation for ACL, AMR, superficial MCL, deep MCL, PMC and PHMM, respectively, were 13%, 6.9%, 4.6%, 3.9%, 13% and 8%. The relative gains in external rotation for ACL, AMR, superficial MCL, deep MCL, PMC and medial meniscus, respectively, were 8.9%, 6%, 9.7%, 13.8%,11.2% and 8.5%. All the relative gains in translation, internal and external rotations were significant at each step of transection (p < 0.01).

Conclusions

The ligamentous structures of the medial plane constitute a functional unit in which each component has a specific passive contribution. This study highlights the importance of recognising the extent of the medial ligament tears and performing a medial side anatomic and individual reconstruction and a suture of a ramp lesion, in addition to an ACL surgery.

Risk factors and prevalence of ramp lesions in ACL ruptures: An analysis from the registry of the Francophone Arthroscopic Society

PURPOSE

The study aimed to estimate the prevalence of ramp lesions among patients undergoing anterior cruciate ligament (ACL) reconstruction and identify risk factors associated with these lesions.

METHODS

A retrospective, multicentre cohort study was conducted using data from the Francophone Arthroscopic Society's registry, including 5359 patients who underwent ACL reconstruction (ACLR) from June 2020 to June 2023. Potential risk factors for ramp lesion such as patient demographics, revision surgery, pivot shift, side-to-side anteroposterior laxity, medial collateral ligament (MCL) injury, lateral meniscal tear and the volume of ligament remnant were evaluated using multivariate regression analyses. BMI and delay to surgery were also assessed.

RESULTS

Ramp lesions were identified in 822 patients (15.3%). Univariate analysis identified male sex, younger age, revision surgery, lateral meniscal injury, percentage of ACL remnant (all p < 0.0001) and pivot shift (p = 0.0103) as significant risk factors. MCL injury was associated with a lower risk (p < 0.0001). In multivariate analysis, male sex, younger age, revision surgery, lateral meniscal injury and percentage of ACL remnants remained significant risk factors, while MCL injury remained a protective factor. The anteroposterior laxity wasn't a significant predictor in either analysis. In subgroup analysis, there were no differences concerning body mass index (n.s) and the delay to surgery (n.s).

CONCLUSION

The study identified male sex, younger age, revision surgery, lateral meniscal injury and pourcentage of ACL remnant as significant risk factors for ramp lesions, with MCL injury acting as a protective factor. This will help regarding the suspicion and identification of ramp lesions.

LEVEL OF EVIDENCE

Level III.

Evaluating the Diagnostic Performance of MRI for Identification of Meniscal Ramp Lesions in ACL-Deficient Knees: A Systematic Review and Meta-Analysis

BACKGROUND

Despite vigorous efforts to delineate the efficacy of magnetic resonance imaging (MRI) for the diagnosis of meniscal ramp lesions, there is still a great deal of uncertainty regarding its diagnostic performance. Therefore, we conducted a systematic review and meta-analysis to investigate the diagnostic performance of MRI for detecting ramp lesions in anterior cruciate ligament (ACL)-deficient knees.

METHODS

We performed a systematic search of MEDLINE via PubMed, Scopus, Web of Science, and Embase and included all articles, published before October 20, 2022, comparing the accuracy of MRI with that of arthroscopy as the gold standard for diagnosis of ramp lesions. We performed statistical analysis using Stata and Meta-DiSc software. Quality assessment of the included studies was performed using the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2) tool.

RESULTS

This meta-analysis evaluated 21 diagnostic performance comparisons from 19 original research articles (2,149 patients). The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver operating characteristic (SROC) curve for diagnosing a ramp lesion were 0.70 (95% confidence interval [Cl], 0.66 to 0.73), 0.88 (95% Cl, 0.86 to 0.89), 6.49 (95% Cl, 4.12 to 10.24), 0.36 (95% Cl, 0.28 to 0.46), 24.33 (95% Cl, 12.81 to 46.19), and 0.88, respectively. Meta-regression using different variables yielded the same results.

CONCLUSIONS

MRI exhibited a DOR of 24.33 and moderate sensitivity, specificity, and accuracy for diagnosing ramp lesions in ACL-deficient knees. However, arthroscopy using a standard anterolateral portal with intercondylar viewing is recommended to confirm a diagnosis of a ramp lesion.

LEVEL OF EVIDENCE

Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Tunnel Overlap Occurs 25% of the Time With Simultaneous Anterior Cruciate Ligament Reconstruction and Lateral Meniscal Root Repair

Purpose

To assess the risk of socket-tunnel overlap for posterior medial or lateral meniscal root repair combined with anterior cruciate ligament reconstruction (ACLR) using artificial tibias and computed tomography scans for 3-dimensional modeling.

Methods

Artificial tibias (n = 27; n = 3/subgroup) were allocated to groups based on inclination of socket-tunnels (55°, 60°, 65°) created for posterior root of the medial meniscus (MMPR) and lateral meniscus posterior root (LMPR) repair, and ACLR. Three standardized socket-tunnels were created: one for the ACL and one for each posterior meniscal root insertion. Computed tomography scans were performed and sequentially processed using computer software to produce 3-dimensional models for assessment of socket-tunnel overlap. Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney U tests. Significance was set at P < .05.

Results

The present study found no significant risk of tunnel overlap when drilling for combined ACLR and MMPR repair, whereas 7 cases of tunnel overlap occurred between ACL tunnels and LMPR (25.9% of cases). No subgroup or specific pattern of angulation consistently presented significantly safer distances than other subgroups for all distances measured.

Conclusions

This study demonstrated 25.9% rate of overlap for combined LMPR repair and ACLR, compared with 0% for MMPR repair with ACLR. Lower ACL drilling angle (55 or 60°) combined with greater lateral meniscus drilling angle (65°) produced no socket-tunnel overlap.

Clinical Relevance

Socket-tunnel overlap during meniscal root repair combined with ACLR may compromise graft integrity and lead to impaired fixation and treatment failure of either the ACL, the meniscus, or both. Despite this, risk for socket-tunnel overlap has not been well characterized.

Optimizing Socket-Tunnel Position for Meniscal Allograft Transplantation Combined With ACL Reconstruction: A 3D Model Analysis

Background

Socket-tunnel overlap during meniscal allograft transplantation (MAT) combined with anterior cruciate ligament reconstruction (ACLR) may compromise graft integrity and lead to impaired fixation and treatment failure.

Purpose/Hypothesis

The purpose of this study was to determine optimal socket-tunnel drilling parameters for medial and lateral MAT with concurrent ACLR using artificial tibias and computed tomography (CT) scans for 3-dimensional (3D) modeling. It was hypothesized that clinically relevant socket tunnels could be created to allow for concurrent medial or lateral MAT and ACLR without significant risk for overlap at varying tunnel guide angles.

Study Design

Descriptive laboratory study.

Methods

A total of 27 artificial right tibias (3 per subgroup) were allocated to 9 experimental groups based on the inclination of the socket tunnels (55°, 60°, and 65°) created for simulating medial and lateral MAT and ACLR. Five standardized socket tunnels were created for each tibia using arthroscopic guides: one for the ACL tibial insertion and one for each meniscus root insertion. CT scans were performed for all specimens and sequentially processed using computer software to produce 3D models for quantitative assessment of socket-tunnel overlap risk. Statistical analysis was performed with Kruskal-Wallis and Mann-Whitney U tests.

Results

No subgroup consistently presented significantly safer distances than other subgroups for all distances measured. Three cases (11%) and 24 cases (~90%) of tunnel overlap occurred between the ACL tunnel and tunnels for medial and lateral MAT, respectively. Most socket-tunnel overlap (25 of 27; 92.6%) occurred between sockets at depths ranging between 6.3 and 10 mm from the articular surface. For ACLR and posterior root of the lateral meniscus setting, the guide set at 65° increased socket-tunnel distances.

Conclusion

When combined ACLR and MAT using socket tunnels for graft fixation is performed, the highest risk for tibial socket-tunnel overlap involves the ACLR tibial socket and the lateral meniscus anterior root socket at a depth of 6 to 10 mm from the tibial articular surface.

Clinical Relevance

Setting tibial guides at 65° to the tibial articular surface with the tunnel entry point anteromedial and socket aperture location within the designated anatomic "footprint" will minimize the risk for socket-tunnel overlap.

Reduced physiological extrusion of the medial meniscus in axial load-bearing condition in anterior cruciate ligament deficiency

PURPOSE

In this study, ultrasonography was used to measure medial meniscus (MM) extrusion under weight-bearing and nonweight-bearing conditions in both anterior cruciate ligament (ACL)-deficient and ACL-intact knee groups. This study aimed to determine the possible differences between these groups with an eventual impact on meniscal tears in ACL-deficient knees.

METHODS

A total of 107 patients who underwent ACL reconstructive surgery between June 2022 and April 2023 were enroled. After applying exclusion criteria, 37 patients met the conditions for inclusion in the study and formed the ACL deficiency group (Group D). Of the 141 patients presenting to an outpatient clinic who agreed to have ultrasonography conducted on their nondiscomforting contralateral knee, 37 patients matched for age, sex, hip-knee-ankle angle and body mass index with Group D patients were selected for the ACL intact group (Group I). Ultrasonography was used to measure MM extrusion in weight-bearing and nonweight-bearing conditions for all participants.

RESULTS

Seventy-four patients were included in the study (n = 37 per group). The supine position showed an MM extrusion of 1.2 ± 0.7 mm in Group I and 1.2 ± 0.7 mm in Group D (not significant). In the standing position, MM extrusion measured 2.0 ± 0.6 mm in Group I and 1.3 ± 0.8 mm in Group D. The difference in extrusion (Δextrusion) between the two positions was 0.8 ± 0.6 in Group I and 0.1 ± 0.2 in Group D, with statistical significance (p < 0.01). A consistent reduction in MM extrusion during weight-bearing was observed in patients with ACL deficiency, irrespective of the duration of ACL deficiency, age, sex and BMI.

CONCLUSION

ACL deficiency did not significantly impact MM extrusion during nonweight-bearing conditions; however, less MM extrusion was observed in response to axial loading conditions. These findings indicate altered MM biomechanics due to increased anterior-posterior meniscal motion and rotational instability after ACL injury.

LEVEL OF EVIDENCE

Level III.

Anterior Cruciate Ligament-Injured Knees With Meniscal Ramp Lesions Manifest Greater Anteroposterior and Rotatory Instability Compared With Isolated Anterior Cruciate Ligament-Injured Knees

PURPOSE

To investigate the effects of ramp lesion (RL) and its repair on knee instability in patients with anterior cruciate ligament (ACL) injury by quantitatively assessing anteroposterior and rotational knee instability before and after ACL reconstruction.

METHODS

All primary double-bundle ACL reconstructions using hamstring autografts between 2016 and 2021 were evaluated retrospectively. Patients with RLs without other meniscal injuries were included in group R, whereas those with isolated ACL injuries constituted group C. RL was repaired using all-inside devices in all patients in group R. Knee instability, including the amount of anterior tibial translation (ATT), and the acceleration and external rotational angular velocity of the knee joint (ERAV) during the pivot-shift test were assessed at the time of surgery. The pivot-shift test grade was recorded.

RESULTS

A total of 73 patients were included in this study. Preoperatively, group R (n = 23) had significantly greater pivot-shift grades (P = .039), ATT (6.0 mm, group R; 4.5 mm, group C, P < .001), acceleration (6.8, 2.8; P = .037), and ERAV (3.9, 2.8; P = .001) than group C (n = 50). Intraoperatively, ATT (-1.0 mm, -1.0 mm; P < .001), acceleration (1.2, 1.1; P < .001), and ERAV (1.4, 1.2; P < .001) were significantly decreased compared with the preoperative values in both groups. No significant differences in these values were observed between groups R and C.

CONCLUSIONS

ACL-injured knees accompanied by RLs exhibited significantly greater anteroposterior and rotatory instability than knees with isolated ACL injuries; increased knee instability can be effectively addressed by performing RL repair in conjunction with ACL reconstruction. The quantitative assessments employed-specifically measuring ATT, acceleration, and ERAV during the pivot-shift test-have allowed us to delineate these aspects of knee instability with greater precision.

LEVEL OF EVIDENCE

Level Ⅲ, retrospective comparative study.

Influence of hamstring stiffness on anterior tibial translation after anterior cruciate ligament rupture

BACKGROUND

There is a correlation between the hamstring stiffness and the decrease of anterior tibial translation in athletic patients with healthy knees. This observation could question the clinical reliability of the Lachman-Trillat test to detect complete ACL ruptures in patients with an important hamstring stiffness. This study aims to determine if anterior tibial translation is correlated with hamstring stiffness in patients with complete ACL rupture.

METHODS

This is a prospective study including patients with unilateral complete ACL rupture confirmed by MRI. The arthrometer GNRB® was used to measure anterior tibial translation on both knees at 134 N and compute the side-to-side difference. The hamstring stiffness was assessed with the eccentric peak torque using the isokinetic dynamometer CON-TREX. Linear regressions were done between these two parameters on two study groups: one included all patients (GR1), and the other included only isolated ACL injuries without associated lesions (GR2).

RESULTS

Fifty-two patients were included (29 men, 23 women) with an average of 34.9 years old. The mean eccentric peak torque of the hamstrings for pathological knees was 94.9Nm for GR1 and 91.7Nm for GR2. The mean side-to-side difference was 2.42 mm for GR1 and 1.99 mm for GR2. No significant correlations were identified for GR1 (p = 0.66) and GR2 (p = 0.105).

CONCLUSION

No significant linear correlation was found between side-to-side difference measured by GNRB® and hamstring stiffness for pathological knees with complete ACL rupture. These results lead to believe that the Lachman-Trillat clinical test is not influenced by hamstring stiffness.

LEVEL OF EVIDENCE

Prospective study, level of evidence IV.

The Effect of Varying Sizes of Ramp Lesions in the ACL-Deficient and Reconstructed Knee: A Biomechanical Robotic Investigation

BACKGROUND

Conflicting evidence has been reported regarding the biomechanical relevance of ramp lesions (RLs) on knee kinematics. Furthermore, the influence of the defect size of the RLs on anterior tibial translation (ATT) and external rotation (ER) is currently unknown.

PURPOSE

To evaluate the influence of RL defect size on knee kinematics in anterior cruciate ligament (ACL) deficiency and after simulated ACL reconstruction (sACLR).

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight cadaveric knee specimens were tested in a 6 degrees of freedom robotic test setup. Force-controlled clinical laxity tests were performed with 200 N of axial compression in 0°, 30°, 60°, and 90° of flexion: 5 N·m internal rotation (IR)/ER torque, 134 N ATT force, and an anteromedial drawer test consisting of 134 N ATT force under 5 N·m ER torque. After determining the native knee kinematics, the ACL was cut at the tibial insertion, followed by a transosseous refixation to simulate a surgical repair or reconstruction (simulated ACL reconstruction; sACLR). An RL was sequentially created with a length of 1, 2, and 3 cm. Each state of the RL was evaluated in the ACL-deficient state and after sACLR.

RESULTS

In the ACL-deficient state, only an RL of 3 cm length resulted in a significant increase of ATT in 30° of flexion (mean difference 0.73 mm; 95% CI, 0.36-1.1 mm). After sACLR, an RL had no significant effect. When looking at ER, an RL significantly increased ER in full extension in the ACL-deficient state in 2 cm (mean difference 0.9°; 95% CI, 0.08°-1.74°) and 3 cm length (mean difference 1.9°; 95% CI, 0.57-3.25). Furthermore, a 3-cm RL significantly increased IR in 0° of flexion in the ACL-deficient state (mean difference 1.9°; 95% CI, 0.2°-3.6°). No effect of ramp lesions on rotation was found after sACLR.

CONCLUSION

RLs result in a small increase in ATT, ER, and IR in ACL-deficient knees at early flexion angles, but not after sACLR.

CLINICAL RELEVANCE

Small RLs did not change time-zero knee kinematics and may, therefore, be left untreated, especially when the ACL is reconstructed.

Efficacy of all-inside devices in reducing gap and step-off in knee extension for ramp lesion repair: A cadaveric study

PURPOSE

The aim of this study is to assess the dynamics of the tear site of meniscal ramp lesions, particularly considering knee flexion angles, and validate anchor fixation using an all-inside device.

METHODS

Eight Thiel-embalmed paired cadaveric knees with their whole bodies were used in this study. The ramp lesions were created arthroscopically, and ramp lesion dynamics were evaluated by gradually extending the knee from 90° of knee flexion. Changes in the gap and step-off (0: no step-off; 1: cross-sectional overlap exists; and 2: tibial articular surface exposed) were evaluated at 90°, 60°, 30°, and 10° of knee flexion. After dynamic evaluation, all-inside repairs of the ramp lesions using all-inside devices were conducted. Dissection was performed to confirm the position of anchor fixation.

RESULTS

As the knee was extended, the gap significantly decreased at all knee flexion angles. Similarly, the step-off grade decreased as the knee was extended, and the step-off completely disappeared in all cases when the knee was extended from 30° to 10°. The average knee flexion angle at which the gap and step-off completely disappeared was 22.5°. After suturing the ramp lesion, arthroscopic evaluation showed that the gap had disappeared and the step-off had been repaired in all cases. Anchor fixation locations were not found within the joint but were fixed to the semimembranosus tendon or its surrounding articular capsule. Overall, 31% (5/16) anchors were fixed to the attachment site of the semimembranosus tendon, whereas the remaining were fixed to the articular capsule, located peripherally to the semimembranosus tendon.

CONCLUSION

Suturing with an all-inside device for ramp lesions is a good option, and the repair in knee extension was found to be reasonable, considering the dynamics of ramp lesions in this study.

LEVEL OF EVIDENCE

Level IV.

Increased Intra-Articular Internal Tibial Rotation Is Associated With Unstable Medial Meniscus Ramp Lesions in ACL-Injured Athletes: An MRI Matched-Pair Comparative Study

Purpose

To analyze internal tibial rotation through magnetic resonance imaging (MRI) of patients with anterior cruciate ligament (ACL) injuries with and without an unstable medial meniscal ramp lesion (MMRL).

Methods

Retrospective analysis of prospectively data was performed to include all consecutive patients who underwent primary ACL reconstruction (ACLR) between January 2022 and June 2022. Two groups, ACLR + unstable MMRL and ACLR without MMRL, were constituted. Propensity score matching analysis was used to limit selection bias. The angle between surgical epicondylar axes (SEAs) and the tangent line of the posterior tibial condyles (PTCs) was measured to analyze the rotational alignment between distal femur and proximal tibia. MMRLs were defined unstable if they were ≥1 cm, if the lesions extend beyond the lower pole of the femoral condyle, and/or if there was displacement into the medial compartment by anterior probing.

Results

Twenty-eight propensity-matched pairs were included. The ACLR + unstable MMRL presented a significantly greater internal rotation of the tibia compared to ACLR without MMRL (P < .001). An internal tibial rotation was associated with unstable ramp lesions in ACL-injured patients (odds ratio [OR], 0.36; 95% CI, 0.25-0.41; P < .0001). If SEA-PTC was 0°, the sensitivity and specificity of the SEA-PTC angle to detect unstable MMRL were respectively 100% (95% CI, 85%-100%) and 18% (95% CI, 8%-36%). Otherwise, if SEA-PTC angle was -10°, the sensitivity and specificity of the SEA-PTC angle to detect unstable MMRL were respectively 43% (95% CI, 27%-61%) and 96% (95% CI, 81%-100%). Bone edema of the posterior medial tibial plateau was significantly associated with unstable ramp lesions (OR, 1.58; 95% CI, 1.21-2.06; P = .029).

Conclusions

Unstable MMRL concomitant to an ACL rupture was associated with an increased tibial internal rotation.

Level of Evidence

Level III, retrospective comparative trial.

Extrusion and meniscal mobility evaluation in case of ramp lesion injury: a biomechanical feasibility study by 7T magnetic resonance imaging and digital volume correlation

Introduction: The existing body of literature on the biomechanical implications of ramp lesions is limited, leaving a significant gap in our understanding of how these lesions impact joint kinematics and loading in the medial compartment. This cadaveric biomechanical study aims to address this gap by employing an innovative Digital Volume Correlation (DVC) method, utilizing 7 Tesla Magnetic Resonance Imaging (MRI) images under various loading conditions. The primary objective is to conduct a comprehensive comparison of medial meniscal mobility between native knees and knees affected by grade 4 ramp lesions. By focusing on the intricate dynamics of meniscal mobility and extrusion, this work seeks to contribute valuable insights into the biomechanical consequences of medial meniscus ramp lesions. Materials and methods: An initial set of 7T MRI imaging sessions was conducted on two intact native knees, applying load values up to 1500N. Subsequently, a second series of images was captured on these identical knees, with the same loads applied, following the creation through arthroscopy of medial meniscus ramp lesions. The application of DVC enabled the precise determination of the three components of displacement and spatial variations in the medial menisci, both with and without ramp lesions. Results: The measured directional displacements between native knees and injured knees indicate that, following the application of axial compression load, menisci exhibit increased extrusion and posterior mobility as observed through DVC. Discussion: Injuries associated with Subtype 4 medial meniscus ramp lesions appear to elevate meniscal extrusion and posterior mobility during axial compression in the anterior cruciate ligament of intact knees. Following these preliminary results, we plan to expand our experimental approach to encompass individuals undergoing weight-bearing MRI. This expansion aims to identify meniscocapsular and/or meniscotibial insufficiency or rupture in patients, enabling us to proactively reduce the risk of osteoarthritic progression.

Editorial Commentary: Don't Neglect the Medial Side of the Knee in Patients With Anterior Cruciate Ligament Injury

The medial collateral ligament (MCL) of the knee, as well as the posteromedial complex (including the posterior oblique ligament [POL] and ramp lesions of the meniscus) is often considered the "neglected" ligament or corner because of the belief that these anatomic structures have enormous regenerative potential and therefore hardly ever need surgical treatment. In patients with anterior ligament cruciate (ACL) tears, the overall combined prevalence of MCL (superficial [sMCL] and deep [dMCL]) and isolated dMCL injuries is high (16.5% + 24.8% = 41.3%). In terms of the POL, with a restraint to both internal tibial rotation and valgus rotation during extension, I have some doubts regarding its role in anteromedial instability (AMRI). In fact, AMRI of the knee is caused mainly by injury to both the ACL and the MCLs, resulting in coupled anterior tibial translation and external rotation, causing the medial tibial plateau to subluxate anteriorly. The sMCL provides the most substantial restraint, and the dMCL and POL play more minor roles. Finally, in ACL-deficient knees, ramp lesions are prevalent (9.3%-24.0%), and failing to identify and treat these lesions results in knee instability. In my experience, all unstable ramp lesions should be repaired. In ACL-deficient knees in patients with a tibial slope >5°, an occult ramp lesion should be strongly suspected. In summary, the medial compartment of the knee is complex and encompasses many structures (MCL, POL, ramp, tibial slope), and I believe that we will increasingly move toward individualized treatment.

The Effect of Lateral Extra-articular Tenodesis in an ACL-Reconstructed Knee With Partial Medial Meniscectomy: A Biomechanical Study

BACKGROUND

Knee laxity increases with medial meniscectomy in anterior cruciate ligament (ACL)-reconstructed knees; however, the biomechanical effect of an additional lateral extra-articular tenodesis (LET) is unknown.

PURPOSE/HYPOTHESIS

The purpose of this study was to determine the kinematic effect of a LET in knees that underwent combined ACL reconstruction (ACL-R) and partial medial meniscus posterior horn (MMPH) meniscectomy. It was hypothesized that the addition of LET would reduce laxity in the ACL-reconstructed knee.

STUDY DESIGN

Controlled laboratory study.

METHODS

Ten fresh-frozen human cadaveric knees (mean age, 41.5 years) were tested using a robotic system under 3 loads: (1) 89.0 N of anterior tibial (AT) load, (2) 5 N·m of internal rotation (IR) tibial torque, and (3) a simulated pivot shift-a combined valgus of 7 N·m and IR torque of 5 N·m-at 0°, 15°, 30°, 45°, 60°, and 90° of knee flexion. Kinematic data were acquired in 4 states: (1) intact, (2) ACL-R, (3) ACL-R + partial MMPH meniscectomy (MMPH), and (4) ACL-R + partial MMPH meniscectomy + LET (MMPH+LET).

RESULTS

In response to AT loading, there was a significant increase seen in AT translation (ATT) in the MMPH state at all knee flexion angles compared with the ACL-R state, with the highest increase at 90° of knee flexion (mean difference, 3.1 mm) (P < .001). Although there was a significant decrease in ATT at 15° of knee flexion with MMPH+LET (P = .022), no significant differences were found at other knee flexion angles (P > .05). In MMPH with IR torque, a significant increase was observed in IR at all knee flexion angles except 90° compared with the ACL-R state (range, 2.8°-4.9°), and this increase was significantly decreased at all flexion angles with the addition of LET (range, 0.7°-1.6°) (P < .05).

CONCLUSION

Performing a partial MMPH meniscectomy increased ATT and IR in response to AT and IR loads compared with the isolated ACL-R state in a cadaveric model. However, when the LET procedure was performed after partial MMPH meniscectomy, a significant decrease was seen at all knee flexion angles except 90° in response to IR and torque, and a significant decrease was seen at 15° of knee flexion in response to AT load.

CLINICAL RELEVANCE

LET may be a useful adjunct procedure after ACL-R with partial MMPH meniscectomy to reduce knee laxity.

Meniscal and Chondral Injury Patterns in Athletes With Anterior Cruciate Ligament Tear

Anterior cruciate ligament (ACL) tears are a prevalent and debilitating injury among athletes, often accompanied by concurrent meniscal and chondral injuries. This study aimed to present a comprehensive investigation into the patterns and prevalence of meniscal and chondral injuries in athletes with ACL tears. This is a cross-sectional study conducted on 600 athletic patients with ACL tears planned for reconstruction in a duration of five years. A combination of advanced imaging techniques, arthroscopic evaluations, and clinical data was used to provide a comprehensive understanding of the injury profiles of the participant athletes. Those findings were duly recorded and analyzed accordingly. Out of 600 patients, 67% (402) had at least one meniscal or chondral injury while the rest 33% (198) had isolated ACL injuries only. Of the patients, 18% (108) were those who had both meniscal and chondral injuries present. Amongst the 57% (342) of patients who had meniscal injuries, injuries to the medial meniscus, lateral meniscus, and both the meniscus were present in 51% (175), 32% (109), and 17% (58) of patients, respectively. Amongst all associated meniscal injuries (n1 = 404), around 52% (210) tears were present in the body of the meniscus, 31% (125) in the posterior horn, and 17% (69) in the anterior horn. Overall, it was noted that 22.77% (92) of meniscal tears were bucket handle tears of the medial meniscus, 16.08% (65) were complex tears of the posterior horn of the lateral meniscus, and 9.60% (39) were complex tears of the posterior horn of the medial meniscus. Amongst 600 patients, 28% (168) of patients had at least one chondral injury present in association with ACL tear. Further, amongst the total number of chondral lesions reported (n2 =297) in ACL-deficient knees, around 55% (163) of lesions were located on medial femoral condyle, 10% (30) were located on undersurface of patella, 10% (30) were global changes, 7% (20) were on lateral femoral condyle, and 5% (15) were located on medial articulating surface of knee. A total of 61% (181) of chondral lesions were grade II, 21% (62) were grade III, 10%(30) were grade IV, and the least noted were 8% (24) grade I chondral lesions. The study concludes that medial meniscus injury was the most common meniscal injury in ACL-deficient knees and the bucket handle tear of the medial meniscus was the most common type of meniscal tear followed by the complex tear of the posterior horn of the medial meniscus. Further, the study also concludes that the medial femoral condyle is the most common site of chondral lesions in ACL-deficient knees.

Arthroscopic All-Suture Anchor Technique for Unstable Ramp Lesions with Medial Meniscal Defects

A ramp lesion is a specific type of tear in the meniscocapsular junction of the posterior horn of the medial meniscus, usually associated with anterior cruciate ligament (ACL) injury. Biomechanical cadaveric studies have shown that ACL injury combined with ramp lesions significantly increases anterior tibial translation and external rotation, which ACL reconstruction alone cannot completely control. Additionally, ramp lesions are sometimes associated with medial meniscal defects, especially in cases of chronic ACL deficiency after repetitive traumatic events, in which the anatomical repair of the meniscocapsular junction is infeasible. This report describes a new arthroscopic repair technique using an all-suture anchor through a posteromedial portal for unstable ramp lesions with medial meniscal defects.

The meniscotibial ligament role in meniscal extrusion: a systematic review and meta-analysis

INTRODUCTION

The meniscotibial ligament (MTL) limits extrusion of the medial meniscus (MM). While meniscal extrusion may be detrimental to knee joint biomechanics, the role of the MTL in meniscal extrusion is debatable. We sought to perform a systematic review and meta-analysis to evaluate the role of the MTL and surgical techniques for MTL repair.

MATERIALS AND METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines we searched PubMed, Cochrane Library, and Embase for: (("Meniscotibial") OR ("Coronary") OR ("Ramp")) AND ("Extrusion"). After screening and applying eligibility criteria, data were extracted for MTL pathology types ("traumatic" ruptures or "induced" injuries) and meniscal extrusion. A meta-analysis evaluated the mean difference of extrusion between "intact" MTLs (native or repaired) and "injured" MTLs (induced or traumatic). We further performed a subgroup analysis between traumatic and induced MTL lesions.

RESULTS

This systematic review included six studies, which all evaluated MM extrusion. There were 74 knees with induced MTL injuries and 19 knees with traumatic MTL ruptures. Study designs were heterogenic and utilized three types of MTL repair procedures. The meta-analysis included 18 human knees and revealed that sectioning the MTL created a 2.92 mm [- 0.18 to 6.03] MM extrusion, while MTL repair decreased MM extrusion by - 2.11 mm [- 3.03 to - 1.21].

CONCLUSIONS

MTL injury may result in approximately 3 mm of MM extrusion, while repair of the MTL can decrease extrusion by 2 mm. Several novel surgical techniques exist to repair the MTL. However, studies reporting clinical outcomes of these various procedures are scarce.

Concurrent Repair of Medial Meniscal Ramp Lesions and Lateral Meniscus Root Tears in Patients Undergoing Anterior Cruciate Ligament Reconstruction: The "New Terrible Triad"

Recent studies have suggested that up to 8% of patients with anterior cruciate ligament (ACL) tears can present with a combined medial meniscal ramp lesion (MMRL) and lateral meniscus root tear (LMRT). MMRLs and LMRTs often are missed preoperatively and can increase the risk of ACL graft failure if left untreated. Given the potential synergistic biomechanical consequences and challenging repair techniques used for treatment, our group commonly refers to this presentation (MMRL-LMRT-ACL) as the "new terrible triad" of ACL pathology. This Technical Note aims to describe a systematic approach for arthroscopic assessment and our preferred inside-out and transtibial pull-out repair techniques to efficiently diagnose and treat a combined MMRL and LMRT at the time of ACL reconstruction surgery.

Greater Knee Rotatory Instability After Posterior Meniscocapsular Injury Versus Anterolateral Ligament Injury: A Proposed Mechanism of High-Grade Pivot Shift

Background

For anterolateral rotatory instability as a result of secondary soft tissue injuries in anterior cruciate ligament (ACL)-deficient knees, there is increasing interest in secondary stabilizers to prevent internal rotation (IR) of the tibia.

Purpose

To determine which secondary stabilizer is more important in anterolateral rotatory instability in ACL-deficient knees.

Study Design

Controlled laboratory study.

Methods

The lower extremities of 10 fresh-frozen cadavers (20 extremities) without anterior-posterior or rotational instability were included. Matched-pair randomization was performed, with each side per specimen assigned to 1 of 2 groups. In group 1, the ACL was sectioned, followed by the anterolateral ligament (ALL); in group 2, the ACL was sectioned, followed by sequential sectioning of the posterolateral meniscocapsular complex (PLMCC) and posteromedial meniscocapsular complex (PMMCC). The primary outcome was the change in relative tibial IR during a simulated pivot-shift test with 5 N·m of IR torque and 8.9 N of valgus force. The secondary outcomes were the International Knee Documentation Committee grade in the pivot-shift test and the incidence of the grade 3 pivot shift.

Results

In group 1, compared with baseline, the change in relative tibial IR at 0° of knee flexion was 1.4° (95% CI, -0.1° to 2.9°; P = .052) after ALL release. In group 2, it was 2.5° (95% CI, 0.4° to 4.8°; P = .007) after PLMCC release and 4.1° (95% CI, 0.5° to 7.8°; P = .017) after combined PLMCC and PMMCC release. Combined PLMCC and PMMCC release resulted in greater change of tibial IR with statistical significance at 0°, 15°, and 30° of knee flexion (P = .008, .057, and .004, respectively) compared with ALL release. The incidence of grade 3 pivot shifts was 10% in group 1 and 90% in group 2.

Conclusion

Posterior meniscocapsular laxity caused an increase in relative tibial IR as much as ALL injury in ACL-deficient knees in our simulated laboratory test, and greater anterolateral rotatory instability occurred with posterior meniscocapsular injury compared with ALL injury.

Clinical Relevance

Repair of the injured posterior meniscocapsular complex may be an important treatment option for reducing anterolateral rotatory instability in the ACL-deficient knee.

Meniscal Ramp Repair: Double-Row Anatomic Repair in Acute Anterior Cruciate Ligament Tears

The surgical management of medial meniscus ramp lesions can be challenging. Currently, repairs are performed via a trans-notch view, combined with a single posteromedial working portal. This technique, however, does not allow for a direct and complete visualization of the structures being injured, making a precise appreciation of the injured structures, as well as an anatomical repair, difficult. To overcome this limitation, a 2-portal posteromedial approach has recently been described. It allows better visualization of the mediolateral extent of the tear and a precise identification of the injured structures. In this Technical Note, an anatomic repair technique using this approach is presented. It consists of a double-row of sutures to repair individually both the meniscotibial and meniscocapsular ligament, thus restoring the 2 main components of the posterior horn of the medial meniscus to their natural insertion site.

Ramp lesion in anterior cruciate ligament injury: a review of the anatomy, biomechanics, epidemiology, and diagnosis

Ramp lesions, commonly observed in patients with anterior cruciate ligament (ACL) injuries, have been previously defined as longitudinal tears around the meniscocapsular junction. However, the definitions and interpretations of ramp lesions have varied, emphasizing the need to confirm their presence before surgery and the importance of direct visualization using arthroscopy. Recent histological studies have reported new findings on ramp lesions, shedding light on their attachment mechanisms. The anatomical structures around the ramp lesion, such as the posterior horn of medial meniscus (PHMM), semimembranosus (SM), posteromedial (PM) capsule, and meniscotibial ligament (MTL), were assessed regarding how these structures could be attached to each other. The studies of ramp lesions have also contributed to the progression of biomechanical studies explaining the cause and effects of ramp lesions. Ramp lesion has been proven to stabilize the anteroposterior (AP) instability of ACL. In addition, various laboratory studies have demonstrated the relationship between rotational instability of the knee joint and ramp lesions. The analysis of risk factors of ramp lesion helped to understand the injury mechanism of the lesion. Many authors have evaluated the prevalence of ramp lesions in patients with ACL injuries. The development of arthroscopy techniques has influenced the outcomes of ACL reconstruction with the easy detection of ramp lesions. This review article aims to analyze the past findings and recent advancements in anatomical, biomechanical, and epidemiological studies of ramp lesions in patients who underwent ACL reconstruction, and provide various perspectives ramp lesions in patients with ACL reconstruction.

Frequency of anterolateral ligament tears and ramp lesions in patients with anterior cruciate ligament tears and associated injuries indicative for these lesions-a retrospective MRI analysis

OBJECTIVES

To assess the frequency of anterolateral ligament (ALL) tears and ramp lesions (RL) detected with MRI in patients with anterior cruciate ligament (ACL) tears and to describe associated injuries indicative for these lesions.

METHODS

In this retrospective study, 164 patients with surgically verified ACL tears were included. Preoperative MRI scans were reviewed for ALL tears and different types of RL. All coexisting meniscal tears, tears of the medial (MCL) and lateral collateral band (LCL), and posterior-medial tibial bone marrow edema (BME) were recorded. The frequency of ALL tears and RL was assessed and coexisting injuries were correlated using Pearson's chi-square test. A p < 0.05 was defined as statistically significant. In cases of multiple testing, Bonferroni's correction was applied.

RESULTS

ALL tears and RL combined were detected in 28 patients (17.1%), ALL tears in 48 patients (29.3%), and RL in 54 patients (32.9%) which were significantly associated to each other. ALL tears were significantly associated with tears of the posterior horn of the lateral meniscus (PHLM), BME, and with tears of the LCL and MCL. RL were significantly associated with tears of the posterior horn of the medial (PHMM) and PHLM, with BME, and with tears of the LCL.

CONCLUSIONS

ACL tears are associated with RL or ALL tears in about one-third of cases and with both lesions combined in about one-fifth of cases. ALL tears and RL are significantly associated with additional posttraumatic injuries, which can thus be indicative of these lesions.

KEY POINTS

• ACL tears were associated with ramp lesions or ALL tears in about one-third of the cases. • Ramp lesions and ALL tears were significantly associated with each other, tear in the PHLM, tear in the LCL, and BME. • ALL tears were more frequently associated with instable classified ramp lesion type 4b and type 5.

Searching for the Best Treatment for Ramp Lesions: A Systematic Review and Network Meta-Analysis

Ramp lesions are a common occurrence in patients with anterior cruciate ligament (ACL) tears. These lesions can be difficult to diagnose due to their concealed nature, and their treatment is crucial due to the stabilizing function of the medial meniscocapsular region. The optimal treatment option for ramp lesions varies depending on the size and stability of the lesion. The purpose of this study was to evaluate the best treatment option for ramp lesions based on the stability of the lesion, including no treatment, biological treatment, and arthroscopic repair. We hypothesize that stable lesions have a favorable prognosis with techniques that do not require the use of meniscal sutures. In contrast, unstable lesions require appropriate fixation, either through an anterior or posteromedial portal. This study is a systematic review and meta-analysis with a level of evidence IV. The study used Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for a systematic review of clinical studies reporting outcomes of ramp lesion treatment. The PubMed/MEDLINE database was searched using Mesh and non-Mesh terms related to ramp lesions, medial meniscus ramp lesions, and meniscocapsular injuries. The inclusion criteria encompassed clinical studies in English or Spanish that reported the treatment of ramp meniscal lesions, with a follow-up of at least six months and inclusion of functional results, clinical stability tests, radiological evaluation, or arthroscopic second look. The analysis included 13 studies with 1614 patients. Five studies distinguished between stable and unstable ramp lesions using different criteria (displacement or size) for assessment. Of the stable lesions, 90 cases received no treatment, 64 cases were treated biologically (debridement, edge-curettage, or trephination), and 728 lesions were repaired. There were 221 repaired unstable lesions. All different methods of repair were registered. In stable lesions, three studies were included in a network meta-analysis. The best-estimated treatment for stable lesions was biological (SUCRA 0.9), followed by repair (SUCRA 0.6), and no treatment (SUCRA 0). In unstable lesions, seven studies using International Knee Documentation Committee Subjective Knee Form (IKDC) and 10 studies using Lysholm for functional outcomes showed significant improvement from preoperative to postoperative scores after repair, with no differences between repairing methods. We recommend simplifying the classification of ramp lesions as stable or unstable to determine treatment. Biological treatment is preferred for stable lesions rather than leaving them in situ. Unstable lesions, on the other hand, require repair, which has been associated with excellent functional outcomes and healing rates.

Medial Meniscal Posterior Horn Suturing Influences Tibial Internal-External Rotation in ACL-Reconstructed Knees

Background

The role of meniscal lesions and repair in combination with anterior cruciate ligament (ACL) injury and reconstruction has not been extensively investigated in vivo and under weightbearing conditions.

Purpose

The purposes of this study were to (1) compare the in vivo knee kinematics between patients with ACL tear and those with combined ACL and medial meniscal tears and (2) investigate kinematic differences between isolated ACL reconstruction and ACL reconstruction plus medial meniscal repair (MR). It was hypothesized that concomitant posterior horn medial meniscal tear and ACL deficiency would affect knee internal-external rotation and anterior-posterior translation but MR would restore these parameters.

Study Design

Controlled laboratory study.

Methods

Nineteen patients who underwent ACL reconstruction were included: 10 had intact menisci (IM group) and 9 had a medial meniscal injury that was repaired during ACL reconstruction using an all-inside technique (MR group). Preoperatively and 18 months postoperatively, active knee kinematics under weightbearing conditions was evaluated during a single-leg squat using a dynamic biplane x-ray imaging system. The general linear model was used to investigate the differences between group (IM vs MR) and time (preoperative vs follow-up) and their interactions.

Results

Tibial internal rotation was higher in the MR group than the IM group both before and after surgery (P = .007). Knee valgus rotation was higher in the MR group preoperatively (P < .001), while no differences were found postoperatively because of an increase of valgus rotation in the IM group, which was significant in the descendant phase (P < .001). Preoperatively, the IM group showed a more medial tibial translation compared with the MR group in the descendant phase (P = .006).

Conclusion

When performing a single-leg squat, patients with ACL-deficient knees and a medial meniscal tear demonstrated a more valgus rotation, tibial internal rotation, and lateral tibial translation versus those with intact menisci. After ACL reconstruction and MR, these patients demonstrated significantly higher tibial internal rotation when compared with patients who underwent isolated ACL reconstruction.

Clinical Relevance

Surgeons should be aware that MR does not fully restore knee kinematics in vivo and under weightbearing conditions in the context of ACL reconstruction.

Surgeon anterior cruciate ligament reconstruction volume and rates of concomitant meniscus repair

PURPOSE

The purpose of this study was to assess the effect of surgeon anterior cruciate ligament reconstruction (ACLR) volume on rates of ACLR with concomitant meniscus repair versus meniscectomy and subsequent meniscus surgeries.

METHODS

A retrospective review was conducted from a database of all ACLR performed between 2015 and 2020 at a large integrated health care system. Surgeon volume was categorized as < 35 ACLR per year (low-volume), and ≥ 35 ACLR per year (high-volume). Rates of concomitant meniscus repair and meniscectomy were compared between low-volume and high-volume surgeons. Subgroup analyses compared the rates of subsequent meniscus surgery and procedure time based on surgeon volume and meniscus procedure type.

RESULTS

A total of 3,911 patients undergoing ACLR were included. High-volume surgeons performed concomitant meniscus repair statistically significantly more often than low-volume surgeons (32.0% vs 10.7%, p < 0.001). Binary logistic regression indicated 4.15 times higher odds of meniscus repair among high-volume surgeons. Subsequent meniscus surgery occurred more commonly following ACLR with meniscus repair among low-volume surgeons (6.7% vs 3.4%, p = 0.047), but not high-volume surgeons (7.0% vs 4.3%, p = 0.079). Low-volume surgeons also had longer procedure times for concomitant meniscus repair (129.9 vs 118.3 min, p = 0.003) and meniscectomy (100.6 vs 95.9 min, p = 0.003).

CONCLUSIONS

Data from this study shows that surgeons with lower volume of ACLR select meniscus resection statistically significantly more often than higher-volume surgeons. However, an abundance of literature is available to show that meniscus loss negatively affects the development of post-traumatic osteoarthritis in patients Therefore, as demonstrated in this study by high-volume surgeons, the meniscus should be repaired and protected whenever possible.

LEVEL OF EVIDENCE

III.

Upsurge in publications on ramp lesions of the meniscus: A bibliometric study

PURPOSE

The purpose of this study was to analyze the trends in publications on ramp lesions of the meniscus in the current literature. We hypothesized that publications on ramp lesions have increased rapidly in recent years due to increased knowledge of both clinical and radiological pathology.

METHODS

A Scopus search performed on 21/01/23 retrieved 171 documents. A similar search strategy was employed to carry out a search for ramp lesions on PubMed with no time filters and only English articles. The articles were downloaded into Excel software, and citations for PubMed articles were determined from the iCite website. Analysis was performed using Excel. Using Orange software, data mining was performed from the titles of all articles.

RESULTS

There are a total of 126 publications from 2011 to 2022 with a total of 1778 citations in PubMed. Of all publications, 72% were published in the last 3 years, from 2020 to 2022, indicating an exponential increase in interest in this subject in recent years. Similarly, 62% of the citations were aggregated by the years 2017-2020, both years included. When the journals were analyzed according to the number of citations, the American Journal of Sports Medicine (AJSM) topped with 822 citations (46% of all citations) and 25 publications, followed by Knee Surgery, Sports Traumatology, Arthroscopy (KSSTA) with 27 articles and 388 citations (22% of all citations). When analyzed by citations per publication for different types of studies, randomized clinical trials (RCTs) were the most cited, with 32 citations per publication, followed by basic science articles with 31.5. Most of the basic science articles were cadaver studies examining anatomy, technique, and biomechanics. Technical notes were the third most cited at 18.64 per publication. While the USA is the country that leads publications, France is in a significant second position contributing to research on this topic, followed by Germany and Luxembourg.

CONCLUSIONS

Global trend analysis suggests that ramp lesion research has significantly increased and that the number of papers on the topic is steadily increasing. We found that the publications and citations presented a rising trend, the majority of the highly cited papers were contributed by a few centers, and the most cited were randomized clinical trials and basic science studies. The long-term outcomes of conservatively and surgically treated ramp lesions have attracted the most research interest.

New Considerations in ACL Surgery: When Is Anatomic Reconstruction Not Enough?

➤ Clinicians should be careful to assess for associated injuries including anterolateral complex and medial meniscal ramp lesions or lateral meniscal posterior root tears.➤ Consideration of lateral extra-articular augmentation should be given for patients with >12° of posterior tibial slope.➤ Patients with preoperative knee hyperextension (>5°) or other nonmodifiable risk factors, including high-risk osseous geometry, may benefit from a concomitant anterolateral augmentation procedure to improve rotational stability.➤ Meniscal lesions should be addressed at the time of anterior cruciate ligament reconstruction with meniscal root or ramp repair.

Repair of Ramp Lesions of the Medial Meniscus With ACL Reconstruction Can Better Restore Knee Stability: A Cadaveric Study

Background

Ramp lesions of the medial meniscus have an impact on joint stability in anterior cruciate ligament (ACL)-deficient knees, but the impact of lesion length and repair is unclear.

Purpose/Hypothesis

The purpose of this cadaveric study was to evaluate the effect of medial meniscal ramp lesion repair on the biomechanics of ACL-deficient knee joints. It was hypothesized that (1) ramp lesions will increase the anterior tibial translation (ATT), internal rotation (IR), and external rotation (ER) in ACL-deficient knee joints; (2) increasing the length of the ramp lesion will further increase the ATT, IR, and ER; and (3) repairing the ramp lesion will reduce the ATT, IR, and ER after ACL reconstruction.

Study Design

Controlled laboratory study.

Methods

Included were 9 fresh-frozen cadaveric specimens (4 left knees, 5 right knees; 6 males and 3 females; mean age, 60 years [range, 40-73 years]). The specimens were tested on a biomechanical rig. Two external loading conditions were applied: a 134-N anterior tibial load and 5-N·m internal/external tibial torque with the knee at full extension and at 15°, 30°, 60°, and 90° of flexion. ATT was tracked via a high-speed video camera. The following knee states were tested: intact; ACL-deficient; ACL-deficient combined with a 5-, 10-, 15-, or 20 mm-long ramp lesion of the medial meniscus; ACL reconstruction; and ACL reconstruction combined with ramp lesion repair. The ATT, IR, and ER at all knee angles were analyzed by 1-way analysis of variance.

Results

The ATT, IR, and ER were significantly increased after cutting of the ACL (P < .05). The ATT, IR, and ER continued to increase when ACL deficiency was combined with ramp lesions of 5 to 20 mm in length (P < .05). The ATT, IR, and ER significantly decreased after ACL reconstruction and ACL reconstruction combined with ramp lesion repair (P < .05).

Conclusion

The laxity of knees with ACL deficiency combined with a ramp lesion of the medial meniscus increased more obviously as the ramp lesion increased in length. In a cadaveric model, ACL reconstruction combined with ramp repair improved knee joint stability.

Reproducibility of MRI in the diagnosis of meniscal ramp lesions: an inter-observer study

BACKGROUND

Meniscal ramp lesions have gained much prominence in recent years due to a significant increase in their diagnosis and their important biomechanical involvement in the knee. A new proposed classification of these lesions has recently been published.

PURPOSE

To evaluate the reproducibility of the new classification of meniscal ramp lesions recently published using magnetic resonance imaging (MRI).

MATERIAL AND METHODS

A total of 249 post-traumatic knee MRI studies were evaluated by three musculoskeletal radiologists independently. Patients with an anterior cruciate ligament (ACL) tear on MRI in addition to a recent history of trauma to the knee for <12 months were included in the study, for a total of 95. We carried out an inter-observer concordance study to analyze whether the new classification is reproducible to detect meniscal ramp lesions and to classify them into their different types.

RESULTS

Among our study cohort of 95 patients, we found 47 (49.5%) ramp lesions. In the inter-observer study, we obtained a good concordance (k = 0.733) in the detection of these lesions and an excellent one (k = 0.843) when the type of lesion is described.

CONCLUSION

This study demonstrates that the new classification of meniscal ramp lesions has good reproducibility on MRI.

ACL surgical trends evolve in the last five years for young European surgeons: results of the survey among the U45 ESSKA members

PURPOSE

Although the outcomes of ACL reconstruction are generally satisfying, there are several patients who do not regain their pre-injury sporting level and suffer persistent symptoms. Orthopaedic practice has evolved significantly over the last five years to address these drawbacks. The aim of the present survey was to analyze the changes in the approach to ACL reconstruction among a population of young ESSKA surgeons dedicated to ACL surgery.

METHODS

The survey was uploaded on the ESSKA website and was accessible to members under the age of 45. The ESSKA society has 1035 U45 members involved in multiple aspects of Orthopaedic practice. One hundred and forty questionnaires were returned. Several aspects of ACL surgery were investigated at baseline and 5 years prior. They included general details such as the volume of ACL reconstructions per surgeon per year, the graft choice in cases of low and high demanding patients, the technique for femoral tunnel drilling and the preferred device for femoral fixation. The approach to the management of damage to peripheral structures, as well as meniscal ramp and root tears were also investigated.

RESULTS

Hamstrings and quadrupled semitendinosus were the preferred graft choice in low-demanding patients (92.9%) while quadriceps tendon is gaining popularity in contact sport practitioners (from 4.3 to 10.7%). The percentage of surgeons using femoral screws had decreased from 37.9 to 29.3 while the percentage of those who used buttons increased from 52.9 to 69.3%. Extra-articular procedures (antero-lateral ligament (ALL) or lateral tenodesis have become popular. The percentage of surgeons who perform an additional peripheral reconstruction rose from 28.5 to 71.5%. Of those who perform the meniscal repair more than 50% of patients rose from 14.3 to 27.9%. Similarly, the percentage of surgeons who performed a medial meniscus ramp lesion repair rose from 29.4 to 54.7%. While the percentage of those who choose to perform a transtibial pull-out repair of lateral meniscus root tears significantly rose from 17.9 to 59.3%.

CONCLUSIONS

The present survey among under 45 years old ESSKA surgeons yields some notable findings. The new evidence on the impact of injuries on peripheral structures and menisci is stimulating surgeons towards a more anatomic approach if identified at the time of ACL reconstruction. This evidence will probably influence future research and decision-making.

LEVEL OF EVIDENCE

IV.

High prevalence of meniscal ramp lesions in anterior cruciate ligament injuries

PURPOSE

To evaluate the prevalence of and factors associated with meniscal ramp lesions on magnetic resonance imaging (MRI) in patients with anterior cruciate ligament (ACL) injuries.

METHODS

Data from the Natural Corollaries and Recovery after ACL injury multicentre longitudinal cohort study (NACOX) were analysed. Only patients who underwent MRI were included in this study. All MRI scans were reviewed by an orthopaedic knee surgeon and a musculoskeletal radiologist. The patients were divided into two groups, those with and without ramp lesions according to MRI findings. Univariable and stepwise forward multiple logistic regression analyses were used to evaluate patient characteristics (age, gender, body mass index, pre-injury Tegner activity level, activity at injury) and concomitant injuries on MRI (lateral meniscus, medial collateral ligament [MCL], isolated deep MCL, lateral collateral ligament, pivot-shift-type bone bruising, posteromedial tibial [PMT] bone bruising, medial femoral condyle bone bruising, lateral femoral condyle [LFC] impaction and a Segond fracture) associated with the presence of meniscal ramp lesions.

RESULTS

A total of 253 patients (52.2% males) with a mean age of 25.4 ± 7.1 years were included. The overall prevalence of meniscal ramp lesions was 39.5% (100/253). Univariate analyses showed that contact sports at ACL injury, pivot-shift-type bone bruising, PMT bone bruising, LFC impaction and the presence of a Segond fracture increased the odds of having a meniscal ramp lesion. Stepwise forward multiple logistic regression analysis revealed that the presence of a meniscal ramp lesion was associated with contact sports at ACL injury [odds ratio (OR) 2.50; 95% confidence intervals (CI) 1.32-4.72; P = 0.005], pivot-shift-type bone bruising (OR 1.29; 95% CI 1.01-1.67; P = 0.04), PMT bone bruising (OR 4.62; 95% CI 2.61-8.19; P < 0.001) and the presence of a Segond fracture (OR 4.38; 95% CI 1.40-13.68; P = 0.001).

CONCLUSION

The overall prevalence of meniscal ramp lesions in patients with ACL injuries was high (39.5%). Contact sports at ACL injury, pivot-shift-type bone bruising, PMT bone bruising and the presence of a Segond fracture on MRI were associated with meniscal ramp lesions. Given their high prevalence, meniscal ramp lesions should be systematically searched for on MRI in patients with ACL injuries. Knowledge of the factors associated with meniscal ramp lesions may facilitate their diagnosis, raising surgeons' and radiologists' suspicion of these tears.

LEVEL OF EVIDENCE

III.

The Role of the Medial Meniscus in Anterior Knee Stability

BACKGROUND

Few studies have compared the force distribution between the anterolateral, posterolateral, and medial structures of the knee.

PURPOSE

To investigate the important structures in an intact knee contributing to force distribution in response to anterior tibial load.

STUDY DESIGN

Controlled laboratory study.

METHODS

Nine fresh-frozen cadaveric knee specimens underwent robotic testing. First, 100 N of anterior tibial load was applied to the intact knee at 0°, 15°, 30°, 60°, and 90° of knee flexion. The anterior cruciate ligament (ACL), anterolateral capsule, lateral collateral ligament, popliteal tendon, posterior root of the lateral meniscus, superficial medial collateral ligament, posterior root of the medial meniscus (MM), and posterior cruciate ligament were then completely transected in sequential order. After each transection, the authors reproduced the intact knee motion when a 100-N anterior tibial load was applied. By applying the principle of superposition, the resultant force of each structure was determined based on the 6 degrees of freedom force/torque data of each state.

RESULTS

At every measured knee flexion angle, the resultant force of the ACL was the largest of the tested structures. At knee flexion angles of 60° and 90°, the resultant force of the MM was larger than that of all other structures with the exception of the ACL.

CONCLUSION

The MM was identified as playing an important role in response to anterior tibial load at 60° and 90° of flexion.

CLINICAL RELEVANCE

In clinical settings, the ACL of patients with a poorly functioning MM, such as tear of the MM posterior root, should be monitored considering the large resultant force in response to an anterior tibial load.

Long-term Natural History of Unrepaired Stable Ramp Lesions: A Retrospective Analysis of 28 Patients With a Minimum Follow-up of 20 Years

BACKGROUND

There is a lack of consensus about whether stable ramp lesions associated with anterior cruciate ligament (ACL) injuries need to be repaired.

PURPOSE/HYPOTHESIS

The purpose of this study was to evaluate how many stable ramp lesions left in situ during ACL reconstruction (ACLR) have subsequently failed after >20 years of follow-up. We hypothesized that ACL-reconstructed knees with ramp lesions left in situ without repair have a high risk of meniscal failure over the long term.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

All patients who underwent arthroscopic ACLR by a single experienced surgeon between January 1998 and December 2000 were evaluated retrospectively. Included were all cases of longitudinal tears in the meniscocapsular junction or the red zone of the posterior horn of the medial meniscus that were left in situ and identified through the anterior portals. Successful anterior probing confirmed a meniscal tear of the posterior segment. A lesion was considered stable if it was ≤2 cm and did not extend beyond the lower pole of the femoral condyle. The following data were collected preoperatively and at the last follow-up: demographics, time to surgery, side-to-side laxity, pivot shift, Lysholm score, subjective International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, Tegner activity scale, and meniscal failure rate. We defined 2 groups based on our findings: medial meniscal failure versus no medial meniscal failure.

RESULTS

A total of 716 knees underwent primary ACLR during this period. The 39 (5.4%) stable unrepaired ramp lesions identified were included in the case series. Mean ± standard deviation follow-up was 262.1 ± 10.5 months. Eleven patients (28%) were lost to follow-up. Of the remaining patients, 8 (28.6%) had a medial meniscal failure, of which 6 (21.4%) were bucket-handle tears. The average time elapsed before complications was 87.8 ± 52 months (range, 6-156 months). The medial meniscal survival rate was 93% at 5 years, 75% at 10 years, and 71% at 15 and 20 years. The failure event mainly happened between 96 and 120 months (8 and 10 years) after ACLR. No risk factors for failure were found, but some trends appeared, such as older age, higher body mass index, and preoperative rotational instability. All postoperative scores were significantly improved at the last follow-up (P < .0001); 16 patients (57%) returned to their sport of choice.

CONCLUSION

With nearly one-third of patients developing meniscal complications, including a large share of bucket-handle tears and mostly occurring 8 years after the ACLR, it may not be wise to leave stable ramp lesions unrepaired.

The presence of high-grade pivot shift test preoperatively is associated with inferior functional outcomes

BACKGROUND

The effect of high-grade preoperative pivot shift test on outcomes of anterior cruciate ligament (ACL) reconstruction surgery is not very well established. The present study was conducted to study the factors associated with high-grade pivot shift test and effect of high-grade preoperative pivot shift test on functional outcomes after ACL reconstruction surgery.

METHODS

Three hundred and sixty-two patients who underwent primary ACL reconstruction surgery were enrolled in the study. The pivot shift test was performed preoperatively under anesthesia in all patients. Side of the meniscal tear, if present at the time of ACL reconstruction, was documented. Patients were divided into two groups depending upon the grade of pivot shift test: group H, high-grade pivot shift (n = 84/362; 23%); and group L, low-grade pivot shift (n = 278/362; 77%). Patients were further divided into two groups depending upon the duration of injury: acute (<6 months) and chronic (>6 months). The functional assessment was done using Lysholm score and Tegner activity scale.

RESULTS

The presence of lateral meniscus tear (27/84 vs. 53/278) or both menisci tear (29/84 vs. 60/278) was associated with high-grade pivot shift (p < 0.05). Chronic ACL tears were also observed to be associated with high-grade pivot shift (p = 0.03). The mean Lysholm score in group H and group L patients was 93.8 ± 5.1 and 95.2 ± 5.3, respectively (p = 0.04). The mean post-op Tegner activity scale in group H was 6.8 and in group L was 7.3 (p = 0.0001). Also, 181/253 (71.5%) patients returned to same or higher level of sports activity in group L as compared to 33/72 (46%) patients in group H. The incidence of graft failure in groups H and L was 6.5% (5/77) and 1.6% (4/257; p = 0.03), respectively.

CONCLUSIONS

The high-grade pivot shift is associated with chronic ACL tear (>6 months) and concomitant lateral meniscus tear. The presence of high-grade pivot shift preoperatively is associated with inferior clinical outcomes and lower rate of return to sports.

LEVEL OF EVIDENCE

Level IV, case-control study.

Meniscal Repair Outcomes at Greater Than 5 Years: A Systematic Review and Meta-Analysis

BACKGROUND

The utilization of meniscal repair techniques continues to evolve in an effort to maximize the rate of healing. Meniscal repair outcomes at a minimum of 5 years postoperatively appear to better represent the true failure rates. Thus, a systematic review and meta-analysis of the current literature was conducted to assess the rate of failure at a minimum of 5 years after meniscal repair.

METHODS

We performed a systematic review of studies reporting the outcomes of meniscal repair at a minimum of 5 years postoperatively. A standardized search and review strategy was utilized. Failure was defined as recurrent clinical symptoms or a meniscal reintervention to repair or resect the meniscus in any capacity, as defined by the study. When reported, outcomes were assessed relative to anterior cruciate ligament (ACL) status, sex, age, and postoperative rehabilitation protocol. Meta-analyses were performed with a random-effects model.

RESULTS

A total of 27 studies of 1,612 patients and 1,630 meniscal repairs were included in this review and meta-analysis. The pooled overall failure rate was 22.6%, while the failure rate of modern repairs (excluding early-generation all-inside devices) was 19.5%. Medial repairs were significantly more likely to fail compared with lateral repairs (23.9% versus 12.6%, p = 0.04). Failure rates were similar for inside-out (14.2%) and modern all-inside repairs (15.8%). Early-generation all-inside devices had a significantly higher failure rate (30.2%) compared with modern all-inside devices (15.8%, p = 0.01). There was no significant difference in meniscal failure rate between repairs with concomitant ACL reconstruction (21.2%) and repairs in ACL-intact knees (23.3%, p = 0.54).

CONCLUSIONS

Modern meniscal repair had an overall failure rate of 19.5% at a minimum of 5 years postoperatively. Modern all-inside techniques appear to have improved the success rate of meniscal repair compared with use of early-generation all-inside devices. Lateral repairs were significantly more likely to be successful compared with medial repairs, while no difference was seen between patients undergoing meniscal repair with and without concomitant ACL reconstruction.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Suture Hook Versus All-Inside Repair for Longitudinal Tears of the Posterior Horn of the Medial Meniscus Concomitant to Anterior Cruciate Ligament Reconstruction: A Matched-Pair Analysis From the SANTI Study Group

BACKGROUND

Secondary meniscectomy rates after repair of longitudinal tears of the posterior horn of the medial meniscus (PHMM) performed concomitantly with anterior cruciate ligament reconstruction (ACLR) are reported to be as high as 25% with an all inside repair technique. Posteromedial portal suture hook repair is an emerging technique; however, it is unknown whether it confers a significantly reduced secondary meniscectomy rate compared with the current gold standard.

PURPOSE/HYPOTHESIS

The primary objective of this study was to compare the secondary meniscectomy rates of suture hook repair and all inside repair for longitudinal tears of the PHMM performed concomitant to ACLR. The secondary outcome was to determine the risk factors associated with the failure of the repair. It was hypothesized that repair with an all inside device would be associated with higher secondary meniscectomy rates when compared with suture hook repair and that concomitant anterolateral ligament reconstruction (ALLR) would confer improved meniscal repair survivorship.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients with longitudinal tears of the PHMM who underwent meniscal repair during primary ACLR between January 2011 and December 2015 at our institution were eligible for the study. Patients undergoing suture hook repair were propensity matched in a 1:1 ratio to patients who underwent all inside repair. At the end of the study period, secondary meniscectomy rates were determined.

RESULTS

The study population comprised 237 matched pairs. The mean follow up was 97.7 ± 17.3 months. Patients who underwent an all inside repair had a >2-fold higher failure rate compared with patients who underwent suture hook repair through a posteromedial portal (31.2% vs 15.6%; P = .0003). Patients in the suture hook repair group undergoing additional ALLR demonstrated a >3-fold higher meniscal repair survival rate compared with all other subgroups (P = .0014). This association was not seen in the all inside repair group. The only statistically significant risk factor for meniscal repair failure was the suture repair technique (hazard ratio, 2.133 [95% CI, 1.383-3.292]; P = .0008).

CONCLUSION

Suture hook repair through a posteromedial portal is associated with a significantly lower secondary meniscectomy rate when compared with the all inside meniscal repair of longitudinal tears of the PHMM performed at the time of ACLR. Furthermore, patients in the suture hook repair group who underwent an additional ALLR had a significantly better meniscal repair survivorship compared with all other subgroups.

Epidemiology of Combined Injuries of the Secondary Stabilizers in ACL-Deficient Knees: Medial Meniscal Ramp Lesion, Lateral Meniscus Root Tear, and ALL Tear: A Prospective Case Series of 602 Patients With ACL Tears From the SANTI Study Group

BACKGROUND

Medial meniscal ramp lesion (MMRL), lateral meniscus root tear (LMRT), and anterolateral ligament (ALL) tear are individual injuries that have been described in patients who have an anterior cruciate ligament (ACL) tear. However, the prevalence of these lesions and their combination has not been defined.

PURPOSES

To define the individual and combined prevalence of MMRL, LMRT, and ALL tears in a case series of patients undergoing ACL reconstruction and to identify the risk factors for combined injuries.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Patients aged >15 years undergoing primary ACL reconstruction between January 2019 and June 2021 were enrolled in the study. A preoperative ultrasound scan was performed to look for an ALL tear. The presence of MMRL and LMRT was determined during a standardized arthroscopy exploration. A multivariate logistic regression model was used to determine the individual effect of patient variables on the risk of associated single, dual, triad, or tetrad injuries (MMRL, LMRT, ALL, ACL), represented by an adjusted odds ratio.

RESULTS

The case series consisted of 602 patients who underwent primary ACL reconstruction. An isolated ACL injury was present in 147 patients (24%). A dual injury was detected in 34 patients (6%) who had ACL-MMRL, 16 (2.65%) who had ACL-LMRT, and 265 (44%) who had ACL-ALL. A triad injury was detected in 80 patients (13.28%) who had ACL-ALL-MMRL, 36 (6%) who had ACL-ALL-LMRT, and 3 (0.5%) who had ACL-MMRL-LMRT. A tetrad injury pattern was detected in 21 patients (3.5%). Multivariate analysis showed that the occurrence of tetrad injury was significantly lower in older patients (adjusted odds ratio by year, 0.93 [95% CI, 0.88-0.99]; P = .028). Identifying LMRT increased the likelihood of finding MMRL-ALL injuries by 2.11 times (95% CI, 1.09-3.12; P = .031).

CONCLUSION

Isolated ACL tear is less common than combined injuries, which are quite frequent. Younger age is a risk factor for combined injuries. The search for damaged secondary stabilizers of the knee must be meticulous and systematic, especially when 1 injured structure has already been diagnosed.

Ramp lesion repair via dual posteromedial arthroscopic portals: A cadaveric feasibility study

BACKGROUND

Ramp lesions are found in 16% to 40% of patients undergoing anterior cruciate ligament reconstruction. The repair technique traditionally involves using a suture hook through a posteromedial portal, with the arthroscope positioned in the intercondylar view via an antero-lateral portal. Ramp lesions may be difficult to visualize and repair, even with a 70° arthroscope. The objective of this study was to assess the feasibility of suturing ramp lesions via dual posteromedial portals for the arthroscope and instruments.

HYPOTHESIS

Dual posteromedial arthroscopic portals allow good visualisation and high-quality suturing of ramp lesions, without inducing specific iatrogenic injuries.

MATERIAL AND METHODS

We used 11 fresh cadaver knees. Two posteromedial portals were created under visualisation via an arthroscope introduced through an antero-lateral portal: one was the traditional instrumental portal and the other, located more proximally, was the optical portal. A 2-cm long ramp lesion was created. A suture hook was used to place one or two stitches of PDS n°0 suture. A probe was used to test the quality and stability of the suturing. The posteromedial plane was then dissected to evaluate the anatomical relationships of the portals.

RESULTS

The dual posteromedial approach allowed the visualisation and hook suturing of the ramp lesions in all 11 cases. A single stitch was placed in 4 cases and two stitches in 7 cases. The suture was always of good quality and stable when tested with the probe. The dissection found no injuries to nerves, blood vessels, or tendons.

CONCLUSION

Ramp lesions can be repaired through a dual posteromedial arthroscopic approach. This surgical technique provides good visibility of these lesions and allows high-quality suturing, with no specific iatrogenic injuries. It is an alternative to ramp lesion repair via a single posteromedial portal, which can be challenging.

LEVEL OF EVIDENCE

IV, experimental study with no control group.

Meniscal Tears, Posterolateral and Posteromedial Corner Injuries, Increased Coronal Plane, and Increased Sagittal Plane Tibial Slope All Influence Anterior Cruciate Ligament-Related Knee Kinematics and Increase Forces on the Native and Reconstructed Anterior Cruciate Ligament: A Systematic Review of Cadaveric Studies

PURPOSE

To obtain a comprehensive list of pathologies that cause increased anterior cruciate ligament (ACL) forces and pathologic knee kinematics to evaluate for in both primary and revision ACL reconstruction to decrease the risk of subsequent graft overload.

METHODS

An electronic search was performed in the Embase and MEDLINE databases for the period between January 1, 1990, and December 10, 2020. All articles investigating medial and lateral meniscal injury, (postero)lateral corner injury, (postero)medial corner/medial collateral ligament injury, valgus alignment, varus alignment, and tibial slope in relation to ACL (graft) force and knee kinematics were included.

RESULTS

Data of 43 studies were included. The studies reported that high-volume medial and lateral meniscectomies, peripheral meniscus tears, medial meniscus ramp tears, lateral meniscus root tears, posterolateral corner injuries, medial collateral ligament tears, increased tibial slope, and valgus and varus alignment were reported to have a significant impact on ACL (graft) force and related knee kinematics.

CONCLUSIONS

This systematic review on biomechanical cadaver studies provides a rationale to systematically identify and treat pathologies in ACL-injured knees, because when undiagnosed or left untreated, these specific concomitant pathologies could lead to ACL graft overload in both primary and revision ACL-reconstructed knees.

CLINICAL RELEVANCE

it is necessary that orthopaedic surgeons who treat ACL-injured knees understand the surgically relevant biomechanical consequences of additional pathologies and use this knowledge to optimize treatment in ACL-injured patients.

Evidence-based rationale for treatment of meniscal lesions in athletes

Meniscal injuries in elite athletes are a common cause of missed game time and even have the potential to be career shortening. In this patient group, care must be paid not only to the pathology, but also to a player's contract status, time in the season, specific demands of his/her sport and position on the field, and future consequences. Successful treatment requires the clinician to understand the player's goals and needs, communicate effectively between all stakeholders, and a have knowledge of the challenges posed by the different types of meniscal tear seen in this population. Paramount is the distinction between injuries to the medial and lateral meniscus. Deficiency of the lateral meniscus, as a result of a tear or a meniscectomy, leads to frequent early problems and inexorably to chondral degeneration thereby affecting an athlete's ability to perform. Therefore, it is strongly recommended to repair the majority of lateral meniscal tears. Medial meniscal tears pose a more challenging treatment dilemma, as the success of partial meniscectomy in achieving reproducible, early return to play must be balanced against the long-term degenerative consequences. Many meniscal tears are correctly treated non-operatively.Level of evidence V.

Outcomes and failure rates after revision meniscal repair: a systematic review and meta-analysis

PURPOSE

The purpose of this meta-analysis is to determine the outcomes and failure rates for revision meniscus repairs in patients with re-tears after primary repair failure.

METHODS

A literature search was conducted using PubMed and Embase with the terms "Meniscus," "Meniscal," "Revised," and "Revision." The search strategy was based on the PRISMA (Preferred Reporting Items for Systematic Meta-Analyses) protocol and included four articles (79 patients). The search criteria were limited to studies reporting outcomes and failure rates. The exclusion criteria included languages other than English, biomechanical studies, letters to editors, non-full text, review articles, meta-analysis, and case reports.

RESULTS

Four comparative studies with 79 patients (53 males, 26 females) with a mean age of 23.9 ± 6.4 years treated with a revision meniscus repair were included in the final analysis. Within this analysis, we found a failure rate of 25.3% (20 of 79 patients). Of these failed repairs, 30.95% (13 of 42) were of the medial meniscus, and 18.9% (7 of 37) were of the lateral meniscus. In the four articles, the postoperative Tegner sports activity score was found to be 6.1 ± 1.6 (range, 2 to 10). The post-operative Lysholm score was reported in three articles (45 patients). At a mean follow-up of 58.3 ± 23.9 months, the mean post-operative Lysholm score was 89.1 ± 7.6 (range, 38 to 100). The Coleman score for the included articles ranged between 52 and 59.

CONCLUSION

This analysis found that revision meniscus repairs in patients with re-tears after primary repair failure result in clinical outcomes similar to that of primary repairs.

Meniscal Ramp Lesions: What the Radiologist Needs to Know

Meniscal ramp lesions are a special type of injury that affects the periphery of the posterior horn of the medial meniscus (PHMM) and/or its meniscocapsular attachments. They are strongly associated with acute and chronic anterior cruciate ligament (ACL) tears. These lesions have gained much prominence in recent years, due to a significant increase in their diagnosis and their important biomechanical involvement in the knee. It is known that their presence in ACL-deficient knees is related to instability and if they are not repaired during ACL reconstruction, they can ultimately cause the failure of the graft. Since this type of injury is often underdiagnosed due to its localization at the "blind" point of arthroscopic vision, it is crucial to make an accurate preoperative diagnosis of them with MRI. The objective of this article is to review the recent literature regarding meniscal ramp lesions and to summarize the anatomical, biomechanical and fundamentally diagnostic aspects, emphasizing the radiological findings described until now.

Survival and Risk Factor Analysis of Arthroscopic Ramp Lesion Repair During Anterior Cruciate Ligament Reconstruction

BACKGROUND

There is a lack of research on the management of ramp lesions associated with anterior cruciate ligament (ACL) injuries. Furthermore, there has been no report of the risk factors for failure of ramp lesion sutures, linked to either the technique used (all-inside suture implant vs suture hook through a posteromedial portal) or the type of lesion (location in the red zone or meniscocapsular junction, longitudinal extension, partial- or full-thickness tear).

PURPOSE

To evaluate the results of arthroscopic repair of ramp lesions and determine the risk factors associated with ramp lesion repair failure, with special focus on their subtype and the suture technique.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

All patients who underwent arthroscopic ramp lesion repair in association with ACL reconstruction between November 2015 and January 2018 were evaluated retrospectively. The following parameters were studied: demographics; clinical history; clinical findings including International Knee Documentation Committee score, complications, time from injury to surgery, side-to-side laxity, and pivot shift; and surgical findings including subtype, surgical management, and type and number of sutures. Failure of the ramp lesion repair was defined at secondary arthroscopy.

RESULTS

Among the 248 lesions analyzed, 18 (7.3%) failures were documented. The failures occurred in 21.1% of repairs managed with the all-inside device versus 4.3% of sutures managed with the suture hook (P = .003). Among the 6 factors included in the Cox model, the only one identified as a risk factor for failure was the type of repair (P = .003), with a risk for the all-inside device that was >5-fold higher than that for the suture hook repair (corresponding hazard ratio, 5.1 [95% CI, 1.8-14.5]). No other complications involving the surgical technique or device were registered.

CONCLUSION

An arthroscopic all-inside technique of meniscal repair of ramp lesions appeared to be safe and effective. It provided excellent healing of the repaired meniscus, with an overall failure rate of 7.3%. The type of suture was associated with failure of the ramp lesion repair, with a significantly higher risk with the all-inside device than with suture hook repair sutures.

Incidência de lesões da rampa meniscal nas reconstruções do ligamento cruzado anterior

Objetivo Avaliar a incidência e o perfil epidemiológico das lesões da rampa meniscal nos pacientes submetidos a cirurgia de reconstrução do ligamento cruzado anterior (LCA), e determinar os fatores de risco relacionados.

Métodos Foram analisados retrospectivamente 824 pacientes submetidos a cirurgia de reconstrução do LCA. Os pacientes que apresentaram instabilidade meniscal medial foram submetidos a avaliação do compartimento posteromedial do joelho. Em caso de lesão, o reparo cirúrgico foi realizado. Potenciais fatores de risco associados às lesões foram analisados.

Resultados A incidência geral de lesões da rampa na população estudada foi de 10,6% (87 lesões em 824 pacientes). A análise multivariada pelo teste do Qui-quadrado demonstrou que a presença de lesões da rampa meniscal foi significativamente associada aos seguintes fatores de risco: lateralidade direita e lesões crônicas. Sexo, idade e atividade esportiva não foram estatisticamente significantes. O futebol foi a causa mais frequente de lesões da rampa relacionadas ao esporte, com 78,2% dos casos. No entanto, não se mostrou ser um fator de risco. De 2014 a 2019, a incidência anual variou de 4,0% a 20,6%.

Conclusão A incidência das lesões da rampa meniscal foi de 10,6% nas cirurgias de reconstrução do LCA, sendo mais frequente em pacientes com lesões crônicas. A incidência anual foi crescente, e variou de 4,0%, em 2014, a 20,6%, em 2019.

Isolated Meniscotibial Ligament Rupture: The Medial Meniscus "Belt Lesion"

Ramp lesions play a major role in both anteroposterior and rotational instability following anterior cruciate ligament rupture. The meniscotibial ligament (MTL) is the most important structure to repair and is the primary stabilizer of the posterior horn of the medial meniscus. The posteroinferior insertion of the MTL on the posterior horn of the medial has been described, forming a posterior "belt." Isolated MTL lesion diagnosis can be challenging, as the absence of a meniscocapsular ligament lesion prevents its correct visualization through transnotch vision. This article details a technique to diagnose and repair the "belt lesion" of the medial meniscus.

Increased Posterior Slope of the Medial and Lateral Meniscus Posterior Horn Is Associated With Anterior Cruciate Ligament Injuries

PURPOSE

To measure the slope of the medial and lateral posterior horn of the meniscus and its contribution to the overall resulting posterior tibial slope (bone and meniscus combined slope) in anterior cruciate ligament-intact (ACLI) and -deficient (ACLD) knees.

METHODS

Magnetic resonance images of intact menisci in patients 16 to 60 years old were included. Posterior tibial bone slope (PTS) and meniscus slope (MS) were measured 25%, 50%, and 75% from the medial and lateral borders of the tibial plateau. Analysis of variance was used to determine differences in posterior tibial slopes between ACLD and ACLI knees and between sexes for ACLD and ACLI knees.

RESULTS

192 ACLI patients (age 35.2 ± 9.6 years, mean ± standard deviation) and 159 ACLD patients (age 34.2 ± 10.3 years) were included. Medial and lateral PTS in ACLD was significantly (P = .00001) higher at 25%, 50%, and 75%. Medial and lateral MS in ACLD was significantly (P = .00001) lower at 25%, 50%, and 75%. There were no significant sex differences for medial or lateral MS in ACLD or ACLI patients (P = .51). The resultant combined medial and lateral slope in ACLD patients was significantly (P = .00001) lower at 25%, 50%, and 75%. There were no significant sex differences in PTS (P = .68), MS (P = .51), or resultant slope (P = .79) CONCLUSIONS: The results of this study strongly suggest that lower meniscal slopes of both the medial and lateral posterior horns are associated with ACL injuries in both males and females. Although the posterior horns reversed the bone PTS to an anterior inclined slope in both ACLD and ACLI patients, both the meniscus slope and the combined resultant slope were significantly lower and more positive at all 6 measured locations in ACLD knees.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Medial meniscal ramp lesions in ACL-injured elite athletes are strongly associated with medial collateral ligament injuries and medial tibial bone bruising on MRI

PURPOSE

Medial menisco-capsular separations (ramp lesions) are typically found in association with anterior cruciate ligament (ACL) deficiency. They are frequently missed preoperatively due to low MRI sensitivity. The purpose of this article was to describe demographic and anatomical risk factors for ramp lesions, and to identify concomitant lesions and define their characteristics to improve diagnosis of ramp lesions on MRI.

METHODS

Patients who underwent anterior cruciate ligament (ACL) reconstruction between September 2015 and April 2019 were included in this study. The presence/absence of ramp lesions was recorded in preoperative MRIs and at surgery. Patients' characteristics and clinical findings, concomitant injuries on MRI and the posterior tibial slope were evaluated.

RESULTS

One hundred patients (80 male, 20 female) with a mean age of 22.3 ± 4.9 years met the inclusion criteria. The incidence of ramp lesions diagnosed at surgery was 16%. Ramp lesions were strongly associated with injuries to the deep MCL (dMCL, p < 0.01), the superficial medial collateral ligament (sMCL, p < 0.01), and a small medial-lateral tibial slope asymmetry (p < 0.05). There was also good correlation between ramp lesions and bone oedema in the posterior medial tibia plateau (MTP, p < 0.05) and medial femoral condyle (MFC, p < 0.05). A dMCL injury, a smaller differential medial-lateral tibial slope than usual, and the identification of a ramp lesion on MRI increases the likelihood of finding a ramp lesion at surgery. MRI sensitivity was 62.5% and the specificity was 84.5%.

CONCLUSION

The presence on MRI of sMCL and/or dMCL lesions, bone oedema in the posterior MTP and MFC, and a smaller differential medial-lateral tibial slope than usual are highly associated with ramp lesions visible on MRI. Additionally, a dMCL injury, a flatter lateral tibial slope than usual, and the identification of a ramp lesion on MRI increases the likelihood of finding a ramp lesion at surgery. Knowledge of the risk factors and secondary injury signs associated with ramp lesions facilitate the diagnosis of a ramp lesion preoperatively and should raise surgeons' suspicion of this important lesion.

LEVEL OF EVIDENCE

Diagnostic study, Level III.