Meniscal ramp lesions: frequency, natural history, and the effect on knee cartilage over 2 years in subjects with anterior cruciate ligament tears.

PURPOSE: (i) To investigate the frequency and natural evolution of meniscal ramp lesions (MRLs) on MRI in subjects with acute ACL tear and (ii) to compare knee cartilage compositional degeneration between subjects with MRLs and subjects without meniscal pathology over 2 years. MATERIALS AND METHODS: Fifty-seven subjects with ACL tears (32 females; age 32.6 ± 8.3 years; BMI 24.5 ± 3.5 kg/m2) from a prospective study were screened for the presence of MRLs. Morphological (high-resolution 3D fast spin-echo) and compositional (T1ρ and T2 mapping) MRI was performed prior to and 2 years after ACL reconstruction. Follow-up MR images were assessed for changes in the signal intensity of the MRLs and the presence of meniscal tears. Differences of compositional parameters were compared between subjects with MRLs and without meniscal lesions using independent samples t tests. RESULTS: MRLs were found in 16% (9/56) of the subjects with ACL tears at baseline. Only one subject with MRLs developed a posterior horn meniscal tear over 2 years. In 12 knees, no meniscal tears were found, which were defined as controls. Most interestingly, cartilage ∆T1ρ of the medial femur and medial tibia increased significantly more in subjects with MRLs compared with controls (mean difference, MF = 6.0 ± 0.8 vs. 2.3 ± 0.6, p = 0.004, and MT = 4.4 ± 1.4 vs. 0.4 ± 0.6, p = 0.027) and medial femur ∆T2 over 2 years increased significantly more in MRL than in control knees (5.1 ± 2.5 ms vs. 2.2 ± 1.9 ms, p = 0.012). CONCLUSION: Subjects with ACL tear presented MRLs in 16% of cases. Compared with controls without meniscal lesions, knees with MRLs demonstrated accelerated degeneration of cartilage composition in the medial knee compartment over 2 years.

MRI appearance of the different meniscal ramp lesion types, with clinical and arthroscopic correlation.

BACKGROUND: Meniscal ramp lesions have been defined as longitudinal vertical peripheral tears of the medial meniscus involving the posterior meniscocapsular ligament, meniscotibial ligament, and/or the red-red zone of the posterior horn. They are heavily associated with anterior cruciate ligament injuries, and because of their potentially important biomechanical role in knee stabilization, injuries to this region may require surgical repair. However, due to their location and lack of general knowledge regarding their different types and associated appearances on magnetic resonance imaging, ramp lesions are routinely underreported. This is compounded by the fact that ramp lesions are also often overlooked during conventional anterior portal arthroscopy when direct visualization is not achieved. PURPOSE: To demonstrate MRI appearances and arthroscopic findings of the different types of meniscal ramp lesions, in the hopes of improving their detection on pre-operative imaging.

Ramp lesions in ACL deficient knees in children and adolescent population: a high prevalence confirmed in intercondylar and posteromedial exploration.

PURPOSE: Ramp lesions are common in ACL deficient knees. Their diagnosis is difficult and, therefore, they may be underestimated. So far, no study analyzed their prevalence in a pediatric population. The diagnosis of these Ramp lesions is of major clinical relevance because of a frequent misestimating and technic difficulties. Ramp lesions might be associated with residual knee pain and instability after ACL reconstruction. The aim of this study was to evaluate the prevalence of ramp lesions explored through a systematic intercondylar and posteromedial arthroscopic approach during an ACL reconstruction in a pediatric and adolescent population. METHODS: Children and adolescents who underwent an ACL reconstruction were screened prospectively between October 2014 and 2016. The presence or absence of a ramp lesion was evaluated after each of three arthroscopic steps: (1) an anterior approach, (2) an intercondylar inspection, and (3) a posteromedial approach. Ramp lesions were screened at each step and their prevalence was evaluated. Furthermore, their presence was correlated to age, weight, size, sex, and state of the physis (open or closed). Finally, the meniscal status on MRI and arthroscopic findings were compared. RESULTS: Fifty-six patients were analyzed. The median age was 14.0 ± 1.3 years (12-17). The median interval between injury and surgery was 11.5 months (1-108). During step 1 (anterior approach), only 1 ramp lesion (2%) was diagnosed. 13 (23%) ramp lesions were found after inspection through the intercondylar notch. No additional lesions were found with a direct view through the posteromedial approach. No correlation between ramp lesions and side, sex, weight, size, or state of physis was found. 10 ramp lesions out of 13 could not be diagnosed on MRI. CONCLUSIONS: The prevalence of ACL-associated ramp lesions in children and adolescents is similar to adult populations. A systematic inspection through the intercondylar notch is recommended during ACL reconstruction to make a precise diagnosis. The posteromedial approach is essentially useful for meniscal repair LEVEL OF EVIDENCE: Testing, previously developed diagnostic criteria in a consecutive series of patients and a universally applied "gold" standard, Level I.

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.

Investigation of the anatomic risk factors in acute anterior cruciate ligament ruptures to develop ramp lesions of the medial meniscus by quantitative MRI.

OBJECTIVE: To investigate the anatomic risk factors of knee in patients with acute non-contact anterior cruciate ligament (aACL) ruptures to develop ramp lesions. METHODS: A total of 202 subjects were retrospectively divided into three groups: (1) aACL ruptures combined with ramp lesions group (n = 76); (2) isolated ACL ruptures group (n = 56) and (3) normal controls group (n = 70). Quantitative morphological parameters on MRI were measured including: diameter of medial femoral condyle (MFC), anterior-posterior length and depth of medial tibial plateau (MTP AP length and depth), lateral posterior tibial slope (LPTS) and medial posterior tibial slope (MTPS), asymmetry of LPTS and MPTS (LMPTS), lateral meniscal slope (LMS), and medial meniscal slope (MMS). RESULTS: The MTP AP length, MTP AP length/MFC diameter ratio, MTP depth, LPTS and the asymmetry of LMPTS showed significant differences among the three groups (p < 0.001). The risk factors associated with the ramp lesions including a longer MTP AP length (OR 1.17, 95% CI 1.00-1.44, p = 0.044), increased MTP depth (OR 1.91, 95% CI 1.22-3.00, p = 0.005) and lager ratio (OR 1.11, 95% CI 1.01-1.22, p = 0.036). The highest AUC was the MTP AP length/MFC diameter ratio (0.74; 95% CI, 0.66-0.82). The combination model increased higher accuracy (0.80; 95% CI, 0.72-0.88). CONCLUSION: Several bony anatomic characteristics of the knee, especially the morphology of medial tibia plateau, are additional risk factors for aACL ruptures to develop ramp lesions. CRITICAL RELEVANCE STATEMENT: Predictive anatomic risk factors of the knee for patients with acute non-contact anterior cruciate ligament (aACL) ruptures to develop ramp lesions, especially the morphology of medial tibia plateau, are detectable by MRI. KEY POINTS: Ramp lesion development can complicate aACL ruptures and requires specific treatment. Longer AP length and increased MTP depth are risk factors for concurrent ramp lesions. Identification of ramp lesions allows for the most appropriate treatment.

Posteromedial tibial plateau bone bruises are associated with medial meniscal ramp lesions in patients with concomitant anterior cruciate ligament ruptures: a systematic review & meta-analysis.

OBJECTIVE: To determine if posteromedial tibial plateau (PMTP) bone bruising on pre-operative MRI is significantly associated with a ramp lesion identified during arthroscopy in patients with concomitant ACL ruptures. METHODS: PubMed, CINAHL, Scopus, Web of Sciences, EMBASE, and Cochrane Library were searched systematically for studies that investigated the association between PMTP bone bruises on preoperative MRI and ramp lesions confirmed during arthroscopy. Eight studies met inclusion criteria. The Methodological Index for Nonrandomized Studies (MINORS) checklist was used to assess quality. A meta-analysis was performed to analyze odds of a ramp lesion after PMTP bone bruising identified on magnetic resonance imaging (MRI). Publication bias was assessed by funnel plot and Egger's linear regression test. RESULTS: There are 2.05 greater odds of medial meniscal ramp lesions in patients with an ACL rupture when PMTP bone bruising is found on preoperative MRI (95% CI, 1.29-3.25; p = 0.002). Heterogeneity of the pooled studies may be substantial (I2 = 65%; p = 0.006). Funnel plot analysis and Egger's linear regression test (p > 0.5) determined no publication bias among the studies included in the meta-analysis. CONCLUSION: Patients with acute ACL injuries and PMTP bone bruising on MRI have 2.05 times greater odds of a concomitant medial meniscal ramp lesion than those without this bone bruise pattern.

Ramp Lesions in Chronic Anterior Cruciate Ligament Injuries.

BACKGROUND: Meniscus ramp lesions associated with anterior cruciate ligament (ACL) injuries are being increasingly reported in the literature. This study was carried out to know the incidence of ramp lesions in ACL injured patients and to study the characteristics of these patients in our population. METHODS: Seventy-five patients who underwent ACL reconstruction from January 2021 to December 2021 were prospectively studied. Patients with multi-ligament injuries or a history of previous knee surgery were excluded. All patients were examined clinically and all underwent MRI examinations. The findings of arthroscopy during ACL reconstruction were recorded and analyzed. RESULT: Seventeen patients had ramp lesions with an incidence of 22.67%. Eight were isolated ramp lesions, and nine had other meniscus injuries. Ramp lesions were identified with 41.18% sensitivity using preoperative MRI. Thirteen out of 17 patients with ramp lesions had increased mobility of the posterior horn of the medial meniscus on anterior probing. The duration from injury to surgery was significantly longer in patients with ramp lesions as compared to patients without ramp lesions. CONCLUSION: A ramp lesion is not an uncommon lesion in ACL injuries and can occur either as an isolated meniscus lesion or in association with other meniscus lesions.Ramp lesions can occur in road traffic accidents as well and are not just sports-related injuries. Ramp lesions are not visible through routine anterior portal diagnostic arthroscopy and their repair adds to the stability of the knee. The absence of ramp lesions on MRI does not rule out their presence; hence, one should always look for ramp lesions in the posteromedial compartment of the knee in all cases undergoing ACL reconstruction.

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.

Diagnostic Performance of Magnetic Resonance Imaging for Detecting Meniscal Ramp Lesions in Patients With Anterior Cruciate Ligament Tears: A Systematic Review and Meta-analysis.

BACKGROUND: The clinical importance of meniscal ramp lesions in patients with anterior cruciate ligament (ACL) tear has emerged as a major issue. However, the diagnostic accuracy of magnetic resonance imaging (MRI) for detecting ramp lesions has a wide range. PURPOSE: To perform a systematic review and meta-analysis of the diagnostic performance of MRI for diagnosing ramp lesion in patients with ACL tear. STUDY DESIGN: Systematic review and meta-analysis. METHODS: A literature search of PubMed, EMBASE, and the Cochrane Library was performed based on the revised guidelines for the PRISMA DTA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Accuracy Studies) statement. Diagnostic performance studies using MRI as the index test and arthroscopy as the reference standard for ramp lesion were included. Bivariate and hierarchical summary receiver operating characteristic modeling was used to evaluate the diagnostic performance. Meta-regression analyses were performed to identify potential sources of heterogeneity. RESULTS: The review and meta-analysis included 9 studies from 8 articles (883 patients with ACL tear and reconstruction). The summary sensitivity, summary specificity, and area under the hierarchical summary receiver operating characteristic for ramp lesion were 0.71 (95% CI, 0.59-0.81), 0.94 (95% CI, 0.88-0.97), and 0.90 (95% CI, 0.87-0.92), respectively. Among the potential covariates, magnet strength (P < .01), patient knee position (P = .04), and MRI interpreter (P = .04) were associated with heterogeneity in terms of sensitivity, whereas magnet strength (P = .03) was associated with heterogeneity in terms of specificity. CONCLUSION: MRI demonstrated moderate sensitivity and excellent specificity for diagnosing ramp lesion. Routine arthroscopic assessment is recommended for the presence of ramp lesion, regardless of whether it is suspected on MRI. Further clinicoradiological studies of diagnostic algorithms are needed for identifying ramp lesion, including high-resolution MRI with appropriate knee position.

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 menisci and articular cartilage: a life-long fascination.

The menisci and articular cartilage of the knee have a close embryological, anatomical and functional relationship, which explains why often a pathology of one also affects the other.Traumatic meniscus tears should be repaired, when possible, to protect the articular cartilage.Traumatic articular cartilage lesions can be treated with success using biological treatment options such as microfracture or microdrilling, autologous chondrocyte transplantation (ACT), or osteochondral transplantation (OCT) depending on the depth and area of the lesion.Degenerative cartilage and meniscus lesions often occur together, and osteoarthritis is already present or impending. Most degenerative meniscus lesions should be treated first conservatively and, after failed conservative treatment, should undergo arthroscopic partial meniscus resection. Degenerative cartilage lesions should also be treated conservatively initially and then surgically; thereby treating the cartilage defect itself and also maintaining the axis of the leg if necessary.Tears of the meniscus roots are devastating injuries to the knee and should be repaired e.g. by transtibial re-fixation.The clinical role of 'ramp' lesions of the meniscus is still under investigation. Cite this article: EFORT Open Rev 2020;5:652-662. DOI: 10.1302/2058-5241.5.200016.

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.

Management of traumatic meniscal tear and degenerative meniscal lesions. Save the meniscus.

Meniscectomy remains one of the most frequent orthopedic procedures, despite meniscal sparing having been advocated for several decades now. Incidence is excessive in the light of scientifically robust studies demonstrating the interest of meniscal repair or of nonoperative treatment for traumatic tear and of nonoperative treatment for degenerative meniscal lesions. It is high time that the paradigm shifted, in favor of meniscal preservation. In traumatic tear, and most particularly longitudinal vertical tear in vascularized zones, repair shows a high success rates in terms of recovery time, functional outcome and cartilage protection. Leaving the meniscus alone may be an option in asymptomatic lesions of the lateral meniscus during anterior cruciate ligament (ACL) reconstruction. Posterior ramp lesions (in associated ACL tear), traumatic root tears and radial lesions are also excellent indications for repair, although it has to be borne in mind that the natural history of these lesions is not completely understood and nonoperative treatment also may be considered. Degenerative meniscal lesions are frequently revealed by MRI in middle-aged or elderly subjects. They are closely related to tissue aging and thus probably to osteoarthritic processes. Meniscectomy was long considered the treatment of choice. All but 1 of the 8 recent randomized studies reported non-superiority of arthroscopy over nonoperative treatment, which should thus be the first-line choice, with arthroscopic meniscectomy reserved for cases of failure, or earlier in case of "considerable" mechanical symptoms. Horizontal cleavage in young athletes is a particular case, requiring meniscal repair, to avoid a meniscectomy, which would inevitably be extensive in a young active patient. More than ever, the take-home message is: save the meniscus!