Unrepaired Ramp Lesions Are Associated With a Higher Risk of Secondary Medial Meniscus Bucket Handle Tear Compared to Lateral Meniscus Bucket Handle Tear After Anterior Cruciate Ligament Reconstruction

Ramp lesions are an underrecognized injury of the posteromedial meniscocapsular junction due to the difficulty of visualizing the tear on magnetic resonance imaging (MRI) or with conventional arthroscopic techniques. The prevalence of a concomitant ramp lesion with an anterior cruciate ligament (ACL) tear may be as high as 39.5%. An ACL tear with an accompanying ramp lesion is associated with increased anterior tibial translation and higher dynamic rotational laxity compared to an isolated ACL injury. Microinstability after an ACL reconstruction (ACLR) is associated with postoperative meniscal bucket handle tears (BHT). However, the relationship between ramp lesions and meniscal BHTs is unclear. The purpose of this study was to compare the risk of a secondary BHT of the medial and lateral menisci after an ACLR with an unrecognized ramp lesion. A retrospective review between January 2016 and December 2021 was conducted. The inclusion criteria were adults aged 18 years or older who sustained a meniscal BHT following an ACLR and had an available preoperative MRI before ACLR. Exclusion criteria were incomplete clinical or radiological data, no ACLR, a meniscal BHT before the ACL injury, multi-ligament knee injury, concomitant osteotomy, revision ACLR, or systemic inflammatory disease affecting healing. An analysis of the clinical and radiological data from initial injury to revision surgery was completed. A fellowship trained musculoskeletal radiologist and knee subspecialized orthopaedic surgeon independently assessed the blinded preoperative MRIs of included patients and documented the prevalence and type of ramp lesions at the time of the index ACLR retrospectively. Chi-Square tests were performed to compare categorical variables and independent t-tests were performed to compare continuous variables between the medial and lateral BHT groups. The predictive value of a ramp lesion for BHT laterality was evaluated using logistic regression. Seventy-six patients comprised of 46 in the medial BHT group and 30 in the lateral BHT group were included. Demographics were similar between the medial and lateral BHT groups. Sixty-one patients were male (80.2%) and the mean age was 31.1 ± 10 years. A retrospective expert analysis of the preoperative MRI demonstrated a ramp lesion in 33 patients in the medial BHT group compared to 13 in the lateral BHT group (p=0.02, odds ratio: 3.2, 95% confidence interval: 1.2, 8.0). In the logistic regression analysis, the only independent factor that predicted the occurrence of a medial BHT compared to a lateral BHT was the presence of a ramp tear on preoperative MRI before the index ACL surgery (logworth = 1.59 (p = 0.03)). After a primary ACLR, an untreated ramp lesion was associated with a postoperative medial BHT more often than a lateral BHT. Unrepaired ramp lesions may be a risk factor for subsequent medial meniscus BHT after primary ACLR.