Abstract
PurposeMedial 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.MethodsPatients 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.ResultsOne 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%.ConclusionThe 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 evidenceDiagnostic study, Level III.
Highlights
“Ramp lesions” were first described by Strobel [47] in 1988 to define a menisco-capsular separation of the posterior horn of the medical meniscus (PHMM) form the posteromedial
It was hypothesized that a steeper medial slope is a risk factor for ramp lesions and that bone oedema at the posterior medial tibial plateau (MTP), and medial collateral ligament (MCL) injuries are associated with these injuries, given that it is logical that the injury mechanics causing the ramp lesion are those occurring with AMRI
The ICC value for reliability of magnetic resonance imaging (MRI) measurements was 0.892 for medial tibial slope and 0.977 for the lateral tibial slope, indicating excellent agreement
Summary
“Ramp lesions” were first described by Strobel [47] in 1988 to define a menisco-capsular separation of the posterior horn of the medical meniscus (PHMM) form the posteromedial. It is in the extended position that magnetic resonance imaging (MRI) of the knee is usually undertaken, compromising detection of ramp lesions since there is no ‘ramp’. This phenomenon may account for the low sensitivity of MRI in identifying ramp lesions, which means ramp lesions are frequently not diagnosed preoperatively [3, 11]. The purpose of this study was to describe demographic and anatomical associated factors for ramp lesions in elite athletes, to identify associated lesions on MRI and define their characteristics. Due to the consequent variation in scanning protocols the sequences used varied For the purpose of the study, and to maintain consistency, only the fluid sensitive sequences were used for image analysis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
