Poster 306: Examining Preoperative Magnetic Resonance Imaging for Medial Meniscal Ramp Lesions in Patients Surgically Treated for Acute Grade III Combined Posterolateral Corner Knee Injuries

OBJECTIVES: While medial meniscocapsular tears (ramp lesions) are commonly associated with isolated anterior cruciate ligament (ACL) injuries, there are limited descriptions of these meniscal injuries in multi-ligament knee injuries (MLKIs). The purposes of this study were: (1) To retrospectively evaluate preoperative MRIs for the presence of ramp lesions in patients surgically treated for acute grade III combined posterolateral corner knee injuries and (2) To determine if a preoperative posteromedial tibia plateau (PMTP) bone bruise is associated with the presence of preoperative ramp lesions on MRI in these same patients. METHODS: Data on consecutive patients at a Level I trauma center with MLKIs between 2001 and 2021 were retrospectively reviewed. Only patients with acute grade III combined PLC injuries who received a magnetic resonance imaging (MRI) scan within 30 days of injury were assessed. Two musculoskeletal radiologists retrospectively reviewed each patient’s preoperative MRI for evidence of ramp lesions and bone bruises (Figure 1). Intra-class correlation coefficients (ICCs) were used to calculate reliability among the reviewers. Multivariate analysis was used to evaluate the relationship between bone bruising patterns and the presence of a ramp lesion on MRI. RESULTS: Sixty-eight patients (79.4% male; mean age, 36.2 ± 13.7 years) with an acute grade III combined PLC injury were included in the study (Table 1). On MRI, the ICC for detection of ramp lesions and PMTP bone bruising were 0.921 and 0.938, respectively. Medial meniscal ramp lesions were diagnosed in 18/68 (26.5%). 11/18 (61.1%) patients with ramp lesions also showed evidence of PMTP bruising, while 13/50 (26.0%) patients without ramp lesions had PMTP bruising (P=0.008) (Table 2). When controlling for age and sex, PTMP bruising was significantly associated with the presence of a ramp lesion in combined PLC injuries (OR, 4.62; P=0.012) (Table 3). CONCLUSIONS: Preoperative medial meniscal ramp lesions were diagnosed on MRI in 26.5% of patients with acute grade III combined PLC injuries. In addition, PMTP bone bruising was significantly associated with the presence of a ramp lesion in patients with a grade III combined PLC injury. These findings demonstrate the need to assess for potential ramp lesions at the time of multi-ligament reconstruction.