A ramp lesion is a tear of the peripheral attachment of the posterior horn of the medial meniscus at the meniscocapsular junction.
Ramp lesions tend to occur near the posterior horn, where they can easily be missed during an arthroscopy.
The meniscus itself is not damaged, but tears away at its junction with the posterior capsule.
Ramp lesions and the ACL
A significant number of anterior cruciate ligament injuries (ACL) have ramp lesions associated with them, and it is important that the surgeon actively probe the meniscocapsular rim to exclude this injury. Ramp lesions can be sutured, but the procedure needs an expert surgeon.
Meniscal Ramp Lesions - Anatomy, Incidence, Diagnosis, and Treatment. Chahla J, Dean CS, Moatshe G, Mitchell JJ, Cram TR, Yacuzzi C and LaPrade RF. Orthop J Sports Med. 2016 Jul; 4(7): 2325967116657815.