Correlation between time from injury to surgery and the prevalence of ramp and hidden lesions during anterior cruciate ligament reconstruction. A new diagnostic algorithm

Increased Time to Surgery After Anterior Cruciate Ligament Tear in Female Patients Results in Greater Risk of Medial Meniscus Tear: A Study of 489 Female Patients

PURPOSE

This study assessed the incidence of meniscal tears in anterior cruciate ligament (ACL)-deficient knees, considering the time between injury and reconstruction in a large sample of female patients. Furthermore, we evaluated whether the rate of meniscal repair or meniscectomy was affected by age and body mass index (BMI).

METHODS

The medical records of 489 patients who underwent ACL-reconstructive surgery between January 2011 and April 2021 were analyzed to collect data on the prevalence of meniscal tears, surgical timing, patient age, and BMI. Logistic regression was performed to estimate the association between the prevalence of meniscal tears and the independent variables of surgical timing, age, and BMI.

RESULTS

Between 24 and 60 months after their injury, female patients showed a statistically significant increase in the presence of associated meniscal lesions when compared with ACL reconstruction performed earlier (odds ratio [OR] of 3.11; 95% 1.06-9.10 confidence interval [CI]), especially for medial meniscal tears, with an OR of 1.94 (95% CI 1.23-3.05, P = .004) between 12 and 24 months. There is a statistically significant difference after 12 months in the rate of meniscal suturing for medial meniscus tears (OR 3.30; CI 1.37-7.91 P = .007). Increasing age was associated with a greater prevalence of meniscal tears up to 30-50 years, but there was no clear association between BMI and associated lesions other than a greater rate of meniscectomies.

CONCLUSIONS

In female patients who experienced an ACL injury, a delay in surgery greater than 12 months is associated with a gradual increase in the risk of nonrepairable medial meniscal tear; this risk becomes statistically significant after 24 months. A high BMI does not seem to have relevance in the onset of associated lesions in women but results in a greater rate of meniscectomies compared with meniscal sutures, whereas age between 30 and 50 years is associated with a greater risk of associated injuries.

LEVEL OF EVIDENCE

III, retrospective comparative prognostic trial.

Epidemiology of Meniscus Injuries in the Military Health System and Predictive Factors for Arthroscopic Surgery

Meniscus injuries occur at a higher rate in the military than the general population. Appropriate management and rehabilitation of meniscus injuries is important for maintaining readiness. The purpose of this study was to describe the health burden of meniscus injuries in the Military Health System (MHS) to identify the surgical intervention rate for meniscus injuries, and to determine which injury characteristics and demographic variables were associated with the likelihood of surgery after injury. The U.S. Department of Defense Management Analysis and Reporting Tool, a database of health care encounters by military personnel and dependents, was queried for encounters associated with a meniscal injury diagnosis between January 1, 2010, and December 31, 2011. Meniscus injuries were categorized into (1) isolated medial, (2) isolated lateral, (3) combined medial and lateral, and (4) unspecified cohorts. Patients under 18 and over 51 years were excluded, as well as patients without records at least 1 year prior to diagnosis or 2 years after. Relevant surgical procedures were identified with the Current Procedural Terminology (CPT) codes for arthroscopic surgery of the knee, meniscus repair, meniscectomy, and anterior cruciate ligament (ACL) reconstruction. There were 2,969 meniscus injuries meeting inclusion criteria during the study period. There were 1,547 (52.1%) isolated medial meniscus injuries, 530 (17.9%) isolated lateral meniscus injuries, 452 (15.3%) involved both menisci, and 435 (14.7%) were unspecified. The mean age was 35.5 years (standard deviation [SD] = 9.3). An adjacent ligamentous injury occurred in 901 patients (30.3%). The treatment course led to arthroscopic surgery in 52.8% (n = 1,568) of all meniscus injuries. Eighty-five percent (n = 385) of combined medial and lateral tears, 54.9% of medial tears, and 51.6% of lateral tears underwent surgery. Partial meniscectomy was the most common procedure performed while 47.2% (n = 1,401) of tears were not treated surgically. Bilateral meniscus injuries had 4.57 greater odds of undergoing knee arthroscopy (95% confidence interval [CI]: 3.46, 6.04), 2.42 times odds of undergoing a meniscus repair, and 4.59 times odds for undergoing a meniscus debridement (95% CI: 3.62, 5.82). The closed nature of the MHS allows reliable capture of surgical rates for meniscus injuries within the military population. Meniscus injuries are common in the military and impose a significant burden on the MHS. Appropriate management and rehabilitation of this injury is important for maintaining readiness.

Meniscal Tear Management Associated with ACL Reconstruction

Meniscal lesions often occur in association with anterior cruciate ligament (ACL) tears at the moment of the injury or, secondarily, as a consequence of knee instability. Both ACL and meniscus lesions are associated with a higher risk of osteoarthritis. Adequate treatment of these lesions reduces the rate of degenerative changes in the affected knee. Meniscal tears should be addressed concomitantly with ACL reconstruction and the treatment must be oriented towards preserving the meniscal tissue anytime this is possible. Several options for approaching a meniscus tear are available. The meniscal suture should always be considered, and, if possible, meniscectomy should be the last choice. “Masterly neglect” is a valuable option in selected cases.

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.

Risk Factors for Ramp Lesions of the Medial Meniscus: A Systematic Review and Meta-analysis

BACKGROUND

Failure to appropriately identify and repair medial meniscal ramp lesions at the time of anterior cruciate ligament (ACL) reconstruction (ACLR) may result in increased anterior tibial translation and internal rotation, increasing the risk for graft failure. Knowledge of the risk factors leading to the development of ramp lesions may enhance clinicians' vigilance in specific ACL-deficient populations and subsequently repair of these lesions at the time of ACLR.

PURPOSE

To perform a systematic review and meta-analysis of factors tested for associations with ramp lesions and to determine which were significantly associated with the presence of ramp lesions.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

PubMed, OVID/Medline, and Cochrane databases were queried in April 2020. Data pertaining to study characteristics and reported risk factors for ramp lesions were recorded. DerSimonian-Laird binary random-effects models were constructed to quantitatively evaluate the association between risk factors and ramp lesions by generating effect estimates in the form of odds ratios (ORs) with 95% CIs. Qualitative analysis was performed to describe risk factors that were variably reported.

RESULTS

The review included 12 studies with 8410 patients. The overall pooled prevalence of ramp lesions was 21.9% (range, 9.0%-41.7%). A total of 45 risk factors were identified, of which 8 were explored quantitatively. There was strong evidence to support that posteromedial tibial edema on magnetic resonance imaging (MRI) (OR, 2.12; 95% CI, 1.27-3.56; P = .004), age <30 years (OR, 2.02; 95% CI, 1.23-3.22; P = .002), and complete ACL tears (OR, 3.0; 95% CI, 1.41-6.20; P = .004) were risk factors for ramp lesions. There was moderate evidence to support that male sex (OR, 1.58; 95% CI, 1.36-1.83; P < .001) and concomitant lateral meniscal tears (OR, 1.54; 95% CI, 1.11-2.13; P = .009) were risk factors for ramp lesions. Chronic ACL injury (≥24 months) demonstrated minimal evidence as a risk factor (OR, 1.41; 95% CI, 1.14-1.74; P = .001). No significant associations were determined between contact injury or revision ACLR and the presence of ramp lesions.

CONCLUSION

Significant associations between male sex, age <30 years, posteromedial tibial edema on MRI, concomitant lateral meniscal tears, complete ACL tears, injury chronicity, and the presence of ramp lesions were found. Contact injury and revision ACLR were not significantly associated with the presence of ramp lesions.

Lateral Meniscus Posterior Root Injury: MRI Findings in Children With Anterior Cruciate Ligament Tear

BACKGROUND. Undiagnosed and unrepaired root tears are increasingly recognized as a preventable cause of accelerated osteoarthritis. Preoperative MRI findings of lateral meniscus posterior root tears in children with concomitant anterior cruciate ligament (ACL) injury are not well described. OBJECTIVE. The purpose of this study was to investigate the performance of preoperative MRI for identifying concomitant lateral meniscus posterior root injuries in pediatric patients with ACL tears with arthroscopy as the reference standard. METHODS. Consecutively registered children who underwent MRI within 90 days before arthroscopic primary ACL reconstruction between March 2017 and December 2019 were included. Two radiologists assessed MRI examinations for direct signs involving the root proper and for findings associated with lateral meniscus posterior root tears. Kappa coefficients for MRI findings were computed. Findings in patients with root tears and intact roots were compared by independent-samples t test, Mann-Whitney U test, chi-square test, Fisher exact test, and multivariable logistic regression analysis. RESULTS. At arthroscopy, 39 children (18 boys, 21 girls; mean age, 15.2 ± 1.4 years) had lateral meniscus posterior root tears; 51 (22 boys, 29 girls; mean age, 15.7 ± 1.8 years) had intact roots. Kappa coefficients ranged from 0.65 to 0.92, aside from tears involving the entheseal segment (κ = 0.55) or popliteomeniscal fascicles (κ = 0.45). MRI findings that were predictors of arthroscopically diagnosed root tear (p < .05) were lateral meniscus root tear in any segment (odds ratio [OR], 16.8; 95% CI, 5.6-50.1), degeneration in any segment (OR, 3.9; 95% CI, 1.6-9.6), coronal cleft sign (OR, 5.7; 95% CI, 2.0-16.7), sagittal ghost sign (OR, 4.8; 95% CI, 1.2-19.1), and axial radial defect sign (OR, 7.1; 95% CI, 2.4-20.5). Tear involving any segment of the root proper had the highest PPV, 82%, with 79% NPV. The coronal cleft, sagittal ghost, and axial radial defect signs had specificities of 88%, 94%, and 88% but sensitivities of 44%, 23%, and 49%. The only significant independent predictor on preoperative MRI was root tear in any segment (OR, 15.8; 95% CI, 2.7-137.5; p = .003). CONCLUSION. Among MRI findings evaluated for preoperative diagnosis of lateral meniscus posterior root tear, tear involving any segment of the root proper had the strongest performance; associated findings had high specificity but low sensitivity. CLINICAL IMPACT. Accurate identification of lateral meniscus posterior root tears on preoperative MRI can aid in operative planning and reduce treatment delay.

Ramp Lesion Subtypes: Prevalence, Imaging, and Arthroscopic Findings in 2156 Anterior Cruciate Ligament Reconstructions

BACKGROUND

Ramp lesions are defined as a particular type of injury within the posterior horn of the medial meniscus and its meniscocapsular attachments. Five subtypes have been described: type 1, meniscocapsular lesion; type 2, partial superior lesion; type 3, partial inferior lesion or hidden type; type 4, complete tear in the red zone; and type 5, complete double tear.

PURPOSE

(1) To determine the prevalence of different subtypes of ramp lesions in patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR). (2) To describe the characteristics of ramp lesions based on imaging and diagnostic arthroscopy.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

All patients who underwent arthroscopic ACLRs between November 2015 and November 2018 by 2 senior surgeons at 1 institution were evaluated retrospectively (1) to describe the subtypes of ramp lesions diagnosed intraoperatively using transnotch arthroscopic exploration of the posteromedial compartment and (2) to look for any factors significantly associated with these subtypes. The following parameters were studied: demographics; history and clinical findings including time between injury and surgery, side-to-side laxity, and pivot shift; lesions missed on magnetic resonance imaging (MRI) scans and medial proximal tibial bone contusion visible on MRI scans; and arthroscopic confirmation of ramp lesion (ie, prevalence), associated lateral meniscal tear, or medial chondral tear.

RESULTS

Out of 2156 primary or revision arthroscopic reconstructions, 334 ramp lesions were confirmed, giving a prevalence of 15.5%. The subtype distribution was as follows: type 1, 47.9%; type 2, 4.8%; type 3, 11.4%; type 4, 28.7%; type 5, 7.2%. Multivariate analysis showed that gross pivot shift was significantly associated with complete ramp tears (odds ratio, 4.8; 95% CI, 1.7-17.2). Hidden lesions (type 3, inferior partial tear in the red zone) were the most likely to be missed on preoperative MRI (45.9%).

CONCLUSION

In a population undergoing ACLR, the prevalence of ramp lesions was 15.5%. Among the subtypes of ramp lesion, the most common was a meniscocapsular junction tear (type 1). Partial inferior tears (type 3) were the most likely to be missed on preoperative MRI scans. Gross pivot shift was significantly associated with complete ramp tears (types 1, 4, and 5).

Adolescents show a lower healing rate of anterolateral ligament injury and a higher rotational laxity than adults after anterior cruciate ligament reconstruction

BACKGROUND

This study aimed to compare anterolateral ligament (ALL) injuries in anterior cruciate ligament (ACL) ruptures, as well as ALL healing and clinical outcomes following ACL reconstruction between adolescents and adults.

METHODS

This retrospective study involved 98 patients who underwent ACL reconstruction. They were divided into two groups according to age: group A (adolescents, 16-20 years of age; n = 49) and group B (adults, 21-45 years of age; n = 49). Subjective scores including ACL-Return to Sport after Injury (ACL-RSI) scale and objective tests were assessed. Follow up magnetic resonance imaging (MRI) and second-look arthroscopy was conducted at 1-year and 2-year follow up, respectively.

RESULTS

Good healing rate of ALL was higher in adults than in adolescents (P = 0.048). Graft tension and synovial coverage showed no significant differences between two groups. Group A showed a higher rate of high-grade pivot shift and a lower ACL-RSI at last follow up than group B (P = 0.126 and P = 0.016). Poor healing of ALL was significantly associated with lower ACL-RSI and failure to return to sports (P < 0.001 and P = 0.001). Re-rupture of the ACL graft was found in four (8.2%) and one (2.0%) of group A and B, respectively.

CONCLUSIONS

Adolescents showed a lower healing rate of ALL, a lower ACL-RSI, a higher rate of high-grade pivot shift than adults. Moreover, poor healing of ALL was significantly associated with a lower ACL-RSI and failure to return to sports. We suggest that adolescents need to pay more attention to the presence of ALL injury.

The popliteomeniscal fascicles: from diagnosis to surgical repair: a systematic review of current literature

Background

Popliteomeniscal fascicles (PMF) are considered the posterolateral meniscocapsular extensions which connect the lateral meniscus to the edge of the tibia. PMFs disruption leads to hypermobility of the lateral meniscus with pain and locking sensation. Recognition and treatment of PMFs tear remain very challenging. The aim of this systematic review is to collect and analyse the articles concerning popliteomeniscal fascicle disruption from diagnosis to surgical approach.

Methods

PubMed, Scopus, Web of Science and EMBASE were searched. Various combinations of the keywords “Popliteomeniscal Fascicles”, “Lateral Meniscus”, “Popliteal Hiatus”, “Posterolateral Corner”, “Tear” and “Surgical Repair” were used. The original literature search identified a total of 85 articles comprising of duplicates. The PRISMA guidilines were followed. Studies in English language and published in peer-reviewed journals were included. Articles with level of evidence I to IV were included

Results

A total of three articles were included in the qualitative analysis. All the articles included are retrospective case series, with a level of evidence IV. Studies concerning patients with pre-operative imaging MRI and clinical assessment, reporting surgical technique and clinical outcomes assessed by physical examination and/or subjective evaluation scales were analysed.

Conclusions

MRI and the Figure-4 test allow to assess PMF tears pre-operatively. Arthroscopic evaluation constitutes the gold standard to confirm the diagnosis. Although surgery is considered resolutive for symptoms, there is still controversy about the most appropriate technique. Further higher quality studies are required.

MRI Criteria for Meniscal Ramp Lesions of the Knee in Children With Anterior Cruciate Ligament Tears

OBJECTIVE. The purpose of this study was to investigate the performance of MRI criteria for identifying meniscal ramp lesions in children with concomitant anterior cruciate ligament (ACL) tear, with arthroscopy used as the reference standard. MATERIALS AND METHODS. This retrospective study included 85 children who underwent a preoperative MRI examination and arthroscopically guided primary ACL reconstruction between June 1, 2017, and December 31, 2019. Blinded to arthroscopic findings, two radiologists reviewed all MRI examinations and reached consensus on the presence or absence of an effusion and various findings within the medial and lateral tibiofemoral joints. Chi-square, Fisher exact, independent t, and Mann-Whitney U tests were used to compare MRI findings between patients with and without arthroscopically confirmed meniscal ramp lesions. RESULTS. At arthroscopy, 35 children (23 boys and 12 girls; mean [± SD] age, 15.7 ± 2.0 years) had ramp lesions and 50 children (22 boys and 28 girls; mean age, 15.1 ± 2.4 years) had intact meniscocapsular junctions. Knees in which a ramp lesion was observed were significantly more likely to have MRI findings of a medial meniscus tear (p = .005), peripheral meniscal irregularity (p = .001), junctional T2-weighted signal (p < .001), and a meniscocapsular ligament tear (p < .001). No significant difference was found between children with and without ramp lesions with regard to the presence of an effusion (p = .65) or a lateral meniscus tear (p = .08) or the extent of medial and lateral tibial plateau marrow edema (p = .67 and p = .83, respectively). CONCLUSION. MRI findings associated with an arthroscopic diagnosis of meniscal ramp lesion include medial meniscus tear, peripheral meniscal irregularity, junctional fluidlike signal, and capsular ligament tear.

RETURN TO PLAY AFTER ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

ABSTRACT The anterior cruciate ligament (ACL) tear represents more than half of all knee injuries in sports that involve body rotations and sudden changes of direction. Discharging the athlete for return to play (RTP) post-ACL reconstruction (ACLR) is a difficult task with multidisciplinary responsibility. For many years, a six-month period post-ACLR was adopted as the only criterion for RTP. However, it is now suggested that RTP should not be exclusively time-based, but to clinical data and systematic assessments. Despite the importance of post-ACLR factors for RTP, pre- and peri-ACLR factors must also be considered. Historically, ACLR is performed with the hamstring or autologous patellar tendons, although the choice of graft is still an open and constantly evolving theme. Anterolateral ligament reconstruction and repair of meniscal ramp tear associated with ACLR have recently been suggested as strategies for improving knee joint stability. Subjective questionnaires are easy to apply, and help identify physical or psychological factors that can hamper RTP. Functional tests, such as hop tests and strength assessment by means of isokinetic dynamometers, are fundamental tools for decision making when associated with clinical evaluation and magnetic resonance imaging. Recently, the capacity to generate force explosively has been incorporated into the muscle strength assessment. This is quantified through the rate of torque development (RTD). Due to characteristics inherent to the practice of sport, there is an extremely short time available for produce strength. Thus, RTD seems to better represent athletic demands than the maximum strength assessment alone. This review investigates the pre-, peri- and post-ACLR factors established in the literature, and shares our clinical practice, which we consider to be best practice for RTP. Level of evidence V; Specialist opinion.

Meniscal ramp lesions should be considered in anterior cruciate ligament-injured knees, especially with larger instability or longer delay before surgery

PURPOSE

To determine the incidence of meniscal ramp lesions in an anterior cruciate ligament (ACL) injured knees and to clarify whether ramp lesions are related to chronic ACL deficiency and increased knee instability.

METHODS

Consecutive ACL injured patients were evaluated arthroscopically for a ramp lesion via a trans-notch view and evidence of menisco-capsular injury was recorded. Other concomitant injuries to the knee were also noted. Incidence of meniscal ramp lesions, delay before surgery, and anterior-posterior stability was analyzed. All patients underwent bilateral KT-2000 evaluation.

RESULTS

One hundred and three consecutive ACL injured patients with a mean age of 24 years were included in this study. In total, a ramp lesion was found in 10 knees (9.7%) via a trans-notch view. None of these lesions could be identified by the standard view from the anterolateral portal. Other medial meniscal lesions were found in 26 knees (25.2%) by standard arthroscopic viewing. The ramp lesion group had significantly longer delay before surgery with a median of 191 days (p < 0.01) as well as a larger side-to-side difference of KT-2000 measurement (7.3 ± 1.8 mm; p < 0.01), compared with the intact medial meniscus group (53 days and 5.5 ± 1.5 mm, respectively).

CONCLUSION

Ramp lesions that were identified using a trans-notch view were not visualized with standard arthroscopic views. Increased anterior tibial translation and longer delay before surgery were seen in knees with ramp lesions. Careful inspection of the posteromedial menisco-capsular region is required as hidden menisco-capsular lesions may occur which may result in residual knee instability.

LEVEL OF EVIDENCE

Level II.

Ramp lesions: a systematic review of MRI diagnostic accuracy and treatment efficacy

Purpose

We conducted a systematic review of the published literature to assess the accuracy of Magnetic Resonance Imaging (MRI) in establishing the presence of ramp lesions (RLs) in Anterior Cruciate Ligament (ACL) deficient knees and the clinical efficacy of the surgical repair of RLs.

Methods

A comprehensive search of the MEDLINE, Web of Science and Scopus databases was performed according to PRISMA guidelines. Studies assessing MRI diagnostic accuracy for RLs or the clinical effect of RL repair in participants with ACL injuries were included. Diagnostic accuracy measures were pooled and plotted in forest plots. Preoperative and at last follow-up treatment efficacy outcome measures were extracted and plotted in forest plots, for graphical comprehension.

Results

Sixteen studies met the criteria and were included. The diagnostic analysis showed a pooled sensitivity, specificity, positive and negative likelihood ratios of 65.1% (95% CI, 59.73 to 70.42), 91.6% (95% CI, 89.14 to 94.05), 2.91 (95% CI, 2.38–3.55) and 0.53 (95% CI, 0.44–0.64), respectively, with high heterogeneity (I² above 80%) for all measures. Treatment analysis showed improved Lysholm Knee Score, IKDC score and laxity difference between the knees in all studies after meniscal suture repair. A separate analysis showed no differences between repair of smaller, stable, RLs with meniscal sutures and repair with abrasion and trephination only.

Conclusion

Although the results present considerable heterogeneity, MRI seems to demonstrate moderate accuracy in the diagnosis of RLs in patients with ACL tear and the surgical repair of RLs can be associated with improved overall outcomes.

The underlying mechanism of partial anterior cruciate ligament injuries to the meniscus degeneration of knee joint in rabbit models

Background

The diagnosis, treatment, and efficacy evaluation of anterior cruciate ligament (ACL) partial rupture remains controversial. This research aims to investigate the underlying mechanism of partial ACL injuries to the meniscus degeneration in the rabbit knee.

Methods

Sixty New Zealand white rabbits were randomly divided into three groups including an experimental group, a sham group (n = 6), and a blank control group (n = 6). The experimental group is composed of an anteromedial bundle (AMB) rupture group (n = 24) and a posterolateral bundle (PLB) rupture group (n = 24). Rabbits in the experimental group were subjected to right hind limbs knee surgery to induce ACL part injury under the arthroscopy. Finally, eight rabbits including 6 in the model group and 2 in the control group were sampled randomly on the 2nd, 4th, and 8th weeks respectively. We observed the typical form of the meniscus through HE staining. Expressions of inflammatory factors including interleukin-1β (IL-1β) and IL-17 in the knee joint fluid were determined by means of an ELISA. Analysis of the mRNA expressions of matrix metalloproteinases-13(MMP-13) was performed to evaluate the inflammatory mediators in the pathogenesis of the meniscus.

Results

HE staining results showed that the surface was rough and the tissues were loose displaying collagen fibers of varying thickness. Both IL-1β and IL-17 in the synovial fluid and the positive rate of MMP-13 in addition to MMP-13 mRNA showed a demonstrable increase treads from the 2nd to the 8th week. The significant difference was found (P < 0.05) compared to the control group.

Conclusion

We conclude that the elevated levels of IL-1β and IL-17, along with increased MMP13 expression, resulted in meniscus degradation in the rabbit knee joint model with partial ACL injury.

Molecular biology of meniscus pathology: Lessons learned from translational studies and mouse models

Injury to any individual structure in the knee interrupts the overall function of the joint and initiates a cascade of biological and biomechanical changes whose endpoint is often osteoarthritis (OA). The knee meniscus is an integral component of knee biomechanics and may also contribute to the biological homeostasis of the joint. Meniscus injury altering knee function is associated with a high risk of OA progression, and may also be involved in the initiation of OA. As the relationship between meniscus injury and OA is very complex; despite the availability of transcript level data on human meniscus injury and meniscus mediated OA, mechanistic studies are lacking, and available human data are difficult to validate in the absence of patient-matched noninjured control tissues. As similarities exist between human and mouse knee joint structure and function, investigators have begun to use cutting-edge genetic and genomic tools to examine the usefulness of the mouse as a model to study the intricate relationship between meniscus injury and OA. In this review, we use evidence from human meniscus research to identify critical barriers hampering our understanding of meniscus injury induced OA and discuss strategies to overcome these barriers, including those that can be examined in a mouse model of injury-mediated OA.

Clinical Characteristics and Outcomes After Primary ACL Reconstruction and Meniscus Ramp Repair

Background:

Satisfactory outcomes have been reported after all-inside meniscus ramp repair with combined anterior cruciate ligament reconstruction (ACLR). However, clinical outcomes after ACLR with inside-out meniscus ramp repair are limited.

Purpose/Hypothesis:

The purpose of this study was to evaluate patient-reported outcomes for patients who underwent ACLR and medial meniscus ramp repair compared with those who underwent isolated ACLR; patients in the 2 groups were matched for age, sex, and sport/activity. The null hypothesis was that there would be no significant differences in clinical outcomes between groups at a minimum of 2 years postoperatively.

Study Design:

Cohort study; Level of evidence 3.

Methods:

Patients who underwent primary ACLR with bone–patellar tendon–bone (BPTB) autograft by a single surgeon were retrospectively identified. A subgroup of patients with combined ACLR and meniscus ramp repair with a minimum 2-year postoperative follow-up were matched to a cohort who underwent isolated ACLR. Subjective patient-reported questionnaires, knee stability, and return to level of activity/sport were collected.

Results:

There were 851 patients who underwent primary ACLR; of these, 158 (18.6%) had medial meniscus ramp lesions confirmed at arthroscopy. The most common clinical characteristics in patients with ramp lesions were chronic injuries (68.4%), contact mechanism (88%), concomitant lateral meniscus tears (63.2%), and concomitant lateral meniscus posterior root tears (22.2%). Further, 50 patients who underwent combined ACLR and meniscus ramp repair with minimum 2-year follow-up were matched to patients who underwent isolated ACLR. Both groups reported significant improvements in subjective outcomes from preoperative to postoperative assessments (P < .001). No significant differences were found in postoperative outcomes for combined ACLR with ramp repair versus isolated ACLR (P > .05). Patients with meniscus ramp repair had increased preoperative knee laxity demonstrated by grade 3 Lachman (44% vs 6%) and pivot-shift (38% vs 12%) test results compared with patients who underwent isolated ACLR (P ≤ .005 for both).

Conclusion:

This study demonstrates similar clinical outcomes, knee stability on postoperative physical examination, and return-to-sport rates for patients who underwent combined ACLR with BPTB autograft and inside-out meniscus ramp repair versus a matched cohort who underwent isolated ACLR. Clinicians should have a high index of suspicion for the presence of ramp lesions in patients with ACL tears who have a contact mechanism of injury, grade 3 Lachman test result, and concomitant lateral meniscal abnormality.

Evaluation of Anterolateral Ligament Healing After Anatomic Anterior Cruciate Ligament Reconstruction

BACKGROUND

Few studies have reported the healing process of anterolateral ligament (ALL) injuries.

PURPOSE/HYPOTHESIS

This study investigated the healing status of ALL injuries after primary anterior cruciate ligament (ACL) reconstruction (ACLR). Additionally, we investigated the association between the healing status of ALL injuries and associated lesions such as osseous lesions and meniscal tears occurring at the time of an ACL rupture. We hypothesized that acute ALL injuries show a high rate (more than two-thirds) of healing at the 1-year follow-up after ACLR and that concomitant lesions observed at the time of an ACL rupture affect the healing status of the ALL.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

We retrospectively investigated patients with ALL injuries who underwent primary ACLR between March 2015 and February 2017. Using magnetic resonance imaging (MRI), we evaluated the features of ALL injuries and concomitant lesions, and MRI was performed at the 1-year follow-up to assess the healing status of the ALL. We investigated the association between the healing status of the ALL and concomitant lesions observed at the time of an ACL rupture. A subjective assessment was performed using the Lysholm score, International Knee Documentation Committee subjective score, and Tegner activity scale. Objective tests included an isokinetic strength assessment and functional performance testing.

RESULTS

With respect to the severity of ALL injuries, of 54 patients, a complete rupture occurred in 16 (29.6%) of the 54 patients and a partial rupture in 38 (70%). A significant association was observed between the severity of ALL injuries and bone contusions (lateral tibial plateau and medial tibial plateau [MTP]) and meniscus ramp lesions (Fisher exact test: P = .023, .012, and .023, respectively). Good and partial healing of the ALL occurred in 16 (29.6%) and 23 (42.6%) of 54 patients, respectively. Scar formation occurred in 12 (22.2%), and nonvisualization of the ALL was observed in 3 (5.6%) of 54 patients. Poor healing of the ALL was associated with preoperative MTP bone contusions and a high-grade pivot shift. Multivariate analysis showed that an MTP bone contusion was an independent risk factor associated with poor healing of the ALL. Among the functional tests performed, significant differences were observed between the good and poor healing groups with respect to the carioca test (P = .039). The good healing group (n = 16) showed a negative pivot shift at the last follow-up, whereas 5 (13.2%) of the patients from the poor healing group (n = 38) showed a positive pivot shift, including 2 (5.3%) with a high-grade pivot shift.

CONCLUSION

Approximately 70% of acute ALL injuries showed poor healing at the 1-year follow-up. Poor healing of ALL injuries was significantly associated with preoperative MTP bone contusions and a high-grade pivot shift. Therefore, a careful assessment of posteromedial bone contusions at the time of an ACL rupture is warranted, particularly in patients with a high-grade pivot shift.

Ramp lesions are frequently missed in ACL-deficient knees and should be repaired in case of instability

PURPOSE

The aim of the current study was (1) to provide an overview of common definitions and classification systems of ramp lesions (RL) and (2) to systematically review the available literature with regard to the diagnosis and treatment of RLs in anterior cruciate ligament (ACL)-deficient knees.

METHODS

Following the PRISMA guidelines, MEDLINE and Scopus were searched for articles (1) reporting on acute or chronic ACL injuries, (2) with concomitant medial meniscus injury, (3) located at the posterior meniscocapsular attachment site (and red-red zone). Ex vivo studies, reviews and technical notes were excluded.

RESULTS

Twenty-seven studies were included based on the criteria mentioned above. RLs are common in ACL-deficient knees with a prevalence ranging from 9 to 24%. RLs should especially be suspected in younger patients, patients with an increased meniscal slope and in patients with prolonged time from injury to surgery. The sensitivity of MRI for the detection of RLs ranges from 48 to 86% at a specificity of 79-99%. For arthroscopy, RLs are easily missed through standard anterior portals (sensitivity 0-38%). RL repair leads to a significant improvement of subjective knee scores, regardless of the specific fixation technique. For stable RLs, the literature suggests equivalent postoperative stability for trephination and abrasion compared to surgical RL repair.

CONCLUSION

Ramp lesions are frequently missed in ACL-deficient knees on standard arthroscopy with anterior portals only. If a RL is suspected, exploration via an additional posteromedial portal is indicated. In case of instability, RL repair should be performed.

LEVEL OF EVIDENCE

IV.

Anatomic risk factor for meniscal lesion in association with ACL rupture

Background

To assess anatomic risk factors for meniscal lesions in association with acute ACL rupture. The primary hypothesis was that tibiofemoral anatomic measures will be different in those with and without concomitant meniscus tears.

Methods

A retrospective review of patients who underwent acute ACL reconstruction in the department was performed. All patients underwent a postoperative CT scan. The concavity and/or convexity on the femur and the tibia were measured by two blinded observers on the sagittal plane with different ratios, and these measures were compared in patients with and without meniscus tears in each compartment. Intra- and inter-rater reliabilities were assessed.

Results

Four hundred twelve patients (268 males and 144 females) were included from October 2012 to February 2015. One hundred sixty-seven patients had a medial meniscal tear (119 males/48 females), and 100 had a lateral meniscal tear (80 males/20 females). The mean time from injury to surgery was 3 months. The average ICC for all measurements was 0.87 (range 0.82–0.98) indicating good reliability. The medial femoral condyle was noted to be significantly longer than the medial tibial plateau in the sagittal plane in patients with a medial meniscal tear (p = 0.04), and the lateral femoral condyle was noted to be significantly longer than the lateral tibial plateau in the sagittal plane in patients with a lateral meniscal tear (p <  0.001). In addition, a less convex lateral tibial plateau was statistically correlated with a higher risk of lateral meniscal tear (p = 0.001).

Conclusions

A greater anteroposterior length of the medial/lateral femoral condyle relative to the medial/lateral tibial plateau is associated with an increased risk of meniscal lesions in association with acute ACL rupture. The lateral compartment in the male population appears to be the most at risk.

Trial registration

Retrospectively registered on May 12, 2016 (CPP sud-est II CAL n°2016-037)

Epidemiological Evaluation of Meniscal Ramp Lesions in 3214 Anterior Cruciate Ligament-Injured Knees From the SANTI Study Group Database: A Risk Factor Analysis and Study of Secondary Meniscectomy Rates Following 769 Ramp Repairs

BACKGROUND

Ramp lesions are characterized by disruption of the peripheral meniscocapsular attachments of the posterior horn of the medial meniscus. Ramp repair performed at the time of anterior cruciate ligament reconstruction (ACLR) has been shown to improve knee biomechanics.

PURPOSE

The primary objectives of this study were to evaluate the incidence of and risk factors for ramp lesions among a large series of patients undergoing ACLR. Secondary objectives were to determine the reoperation rate for failure of ramp repair, defined by subsequent reoperations for partial medial meniscectomy.

STUDY DESIGN

Case-control study; Level of evidence, 3. Case series; Level of evidence, 4.

METHODS

All patients underwent transnotch posteromedial compartment evaluation of the knee during ACLR. Ramp repair was performed if a lesion was detected. Potentially important risk factors were analyzed for their association with ramp lesions. A secondary analysis of all patients who underwent ramp repair and had a minimum follow-up of 2 years was undertaken to determine the secondary partial meniscectomy rate for failed ramp repair.

RESULTS

The overall incidence of ramp lesions in the study population was 23.9% (769 ramp lesions among 3214 patients). Multivariate analysis demonstrated that the presence of ramp lesions was significantly associated with the following risk factors: male sex, patients aged <30 years, revision ACLR, chronic injuries, preoperative side-to-side laxity >6 mm, and concomitant lateral meniscal tears. The secondary meniscectomy rate was 10.8% at a mean follow-up of 45.6 months (range, 24.2-66.2 months). Patients who underwent ACLR + anterolateral ligament reconstruction had a >2-fold reduction in the risk of reoperation for failure of ramp repair as compared with patients who underwent isolated ACLR (hazard ratio, 0.457; 95% CI, 0.226-0.864; P = .021).

CONCLUSION

There is a high incidence of ramp lesions among patients undergoing ACLR. The identification of important risk factors for ramp lesions should help raise an appropriate index of suspicion and prompt posteromedial compartment evaluation. The overall secondary partial meniscectomy rate after ramp repair is 10.8%. Anterolateral ligament reconstruction appears to confer a protective effect on the ramp repair performed at the time of ACLR and results in a significant reduction in secondary meniscectomy rates.