Figure 1
A ramp lesion is a tear or disruption in the peripheral meniscocapsular attachments in the posterior horn of the meniscus (Figure 1). They are common with ACL injuries. It's reported that they are present in around 10-40% of all ACL tears. The posterior horn of the medial meniscus is confluent with the joint capsule. Sometimes, instead of tearing the posterior horn of the medial meniscus, patients will instead tear the capsular attachment to the meniscus. There are two separate ligaments called the meniscotibial and the meniscocapsular ligaments.
Ramp lesions are often difficult to diagnose because they are in what they call a blind spot in the knee. Risk factors for a ramp lesion are age younger than 30 years old, increased time from ACL injury to surgery, and revision ACL reconstruction. Patients that have greater anterior to posterior knee laxity or a higher grade pivot shift may be at higher risk for having a ramp lesion on the medial side of their knee. Oftentimes, it is not obvious on MRI or a diagnostic arthroscopy that a ramp lesion has occurred.
Figure 2
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Figure 4
As such, during a diagnostic arthroscopy at the very beginning of an ACL reconstruction, is important to look closely in the back of the knee near the attachment of the posterior horn of the medial meniscus to see if there is a disruption in the capsule. If there is a tear in this capsule region, it is debatable on which ramp tears are considered stable versus unstable. Nonetheless, it is important to discuss your surgeon's approach to ramp lesions and threshold to repair them. In our practice, we repair nearly all ramp lesions identified during the diagnostic arthroscopy. In fact, Dr. Momaya’s team has published a novel anchor based technique for ramp repair. Figure 2-4 demonstrates the repaired ramp lesion in a collegiate football athlete via a lasso and suture technique.
This post is for educational purposes only. Please consult with your board certified physician for any care related to orthopedic injuries.
