Meniscal ramp lesions should be considered in anterior cruciate ligament-injured knees, especially with larger instability or longer delay before surgery

Abstract

Purpose To determine the incidence of meniscal ramp lesions in an anterior cruciate ligament (ACL) injured knees and to clarify whether ramp lesions are related to chronic ACL deficiency and increased knee instability. Methods Consecutive ACL injured patients were evaluated arthroscopically for a ramp lesion via a trans-notch view and evidence of menisco-capsular injury was recorded. Other concomitant injuries to the knee were also noted. Incidence of meniscal ramp lesions, delay before surgery, and anterior-posterior stability was analyzed. All patients underwent bilateral KT-2000 evaluation. Results One hundred and three consecutive ACL injured patients with a mean age of 24 years were included in this study. In total, a ramp lesion was found in 10 knees (9.7%) via a trans-notch view. None of these lesions could be identified by the standard view from the anterolateral portal. Other medial meniscal lesions were found in 26 knees (25.2%) by standard arthroscopic viewing. The ramp lesion group had significantly longer delay before surgery with a median of 191 days (p < 0.01) as well as a larger side-to-side difference of KT-2000 measurement (7.3 +/- 1.8 mm;p < 0.01), compared with the intact medial meniscus group (53 days and 5.5 +/- 1.5 mm, respectively). Conclusion Ramp lesions that were identified using a trans-notch view were not visualized with standard arthroscopic views. Increased anterior tibial translation and longer delay before surgery were seen in knees with ramp lesions. Careful inspection of the posteromedial menisco-capsular region is required as hidden menisco-capsular lesions may occur which may result in residual knee instability.