Purpose
A ramp lesion is a tear of the peripheral attachment of the posterior horn of the medial meniscus (PHMM) and is the most frequent intra-articular lesion associated with rupture of the anterior cruciate ligament (ACL).1 Its prevalence in cases of ACL rupture varies between 9.3 and 17%.2,3
The PHMM plays an important role in knee stability,
particularly regarding to anterior tibial translation.
In cases of ACL tear,
concomitant ramp lesions may predispose to knee instability,
increased ACL strain and pain.4 However,
due to their location,...
Methods and Materials
We retrospectively reviewed the MRI studies of all arthroscopically-confirmed ramp lesions in our institution between January 2012 and December 2018.
The presence of five MRI features was recorded and analyzed: complete fluid filling between the posterior horn of the medial meniscus and the capsule margin,
edema of the posterior capsule,
medial meniscus irregularity at the posterior margin,
perimeniscal fluid and the “corner notch” sign.
Complete fluid filling between the PHMM and the capsular margin was depicted on sagittal T2-weighted fat-suppressed images.
Edema was considered when...
Results
MRI is an important tool in the evaluation of the posteromedial meniscocapsular junction.
However,
normal anatomy of the posterior capsule and PHMM may mask signs of meniscal ramp lesions when the knee is in near full extension,
making pre-operative MRI diagnosis of meniscal ramp lesions difficult,
with sensitivity ranging from 0-77%.2,3
We identified 6 ramp lesions in our institutions,
only one in a female patient (16.7%).
In our series,
5 patients had an ACL rupture,
which corresponds to 83.3%.
Rupture of the lateral meniscus was...
Conclusion
Pre-operative MRI diagnosis of a ramp lesion in cases of ACL rupture is important since it allows an accurate planning of treatment and implications in missing these lesions are significant.
MRI has a good potential to adequately depict these lesions – as such,
radiologists should be familiar with its imaging features and always look for its presence in cases of ACL tears.
References
1.
Chahla J,
Dean CS,
Moatshe G,
et al.
Meniscal ramp lesions: anatomy,
incidence,
diagnosis,
and treatment.
Orthopaedic Journal of Sports Medicine.
2016;4:2325967116657815.
2.
Liu X,
FengH,
Zhang H,Hong L,WangXS,
Zhang J.
Arthroscopic prevalence of ramp lesion in 868 patients with anterior cruciate ligament injury.
Am J Sports Med.
2011;39:832.
3.
Bollen S.
Posteromedial meniscocapsular injury associated with rupture of the anterior cruciate ligament.
Bone & Joint Journal.
2010;92:222–3.
4.
Ahn JH,
Bae TS,
Kang K-S,
Kang SY,
Lee SH.
Longitudinal tear of the medial...