Summary

Little information is available on the injury mechanism leading to ramp lesions in ACL injuries. In this study, the existence of a ramp lesion was associated with complete ACL tears that occurred with contact with another person. These findings demonstrate that ramp lesions were more frequently observed in high-energy trauma.

Abstract

Introduction

Lesions of the posterior part of the medial meniscus in the meniscosynovial area often occur in association with anterior cruciate ligament (ACL) injuries. Despite a growing interest to understand the former, little is known on the circumstances related to their appearance. The purpose of the study was therefore to compare individual characteristics, injury mechanism and arthroscopic appearance of the ACL remnant between ACL-injured patients with or without an associated ramp lesion. Our hypothesis was that the presence of a ramp lesion was associated to above mentioned characteristics.

Material And Methods

Two hundred and twenty four patients undergoing a primary or revision ACL reconstruction performed by a single surgeon were included prospectively. The presence or absence of a ramp lesion was determined by a systematic arthroscopic inspection of the posteromedial compartment. Chi-square (for categorical variables) and Mann-Whitney (for continuous variables) tests were used to compare the population of ACL-injured patients with and without a ramp lesion regarding: gender, age, body mass index, previous ACL injuries, level of sport practice before injury, mechanism of injury and arthroscopic appearance of the ACL remnant (partial or complete tear). Significance was set at p<0.05. All patients signed a written informed consent. The study protocol had previously been approved by the National Ethics Committee for Research.

Results

Fifty-three patients out of 224 (24%) showed a ramp lesion during arthroscopic inspection. Gender, age, body mass index, previous ipsilateral or contralateral ACL injuries as well as the level of sport practice before injury did not differ between patients with or without a ramp lesion. However, the mechanism of injury was significantly different between both groups (p<0.01). Forty one per cent of patients with a contact ACL injury displayed a ramp lesion versus 19% of patients with a non-contact ACL injury. The type of ACL remnants also significantly differed between both groups (p=0.01). Twenty seven per cent of patients with a complete tear showed a ramp lesion versus 4% of patients with a partial ACL tear.

Discussion

We confirmed that the presence of a ramp lesion associated to the ACL injury was related to the injury mechanism and arthroscopic appearance of the ACL remnant. The presence of a ramp lesion was significantly associated with contact ACL injuries and complete ACL tears. These findings suggest that ramp lesions are more likely to occur in contact lesions (as compared to the relatively lower-energy trauma of non-contact injuries).

Conclusion

Ramp lesions are more likely to appear during contact ACL injuries and could be the result of a higher energy trauma mechanism. Their presence should be systematically investigated through a thorough arthroscopic inspection of the posteromedial compartment. Our findings may contribute to the understanding of their pathogenicity and clinical significance.