Longitudinal tears of the posterior horn of the medial meniscus, intercondylar notch width, and posterior tibial slope are predictive factors for high-grade pivot shift in patients with anterior cruciate ligament rupture.

Abstract

The purpose of this study was to investigate whether meniscal injury and bony factors can predict high-grade pivot shift (HPS). This study retrospectively reviewed patients who underwent reconstruction surgery for anterior cruciate ligament (ACL) rupture. According to the grading of the pivot-shift test under anaesthesia preoperatively, patients were allocated into the HPS group and low-grade pivot shift (LPS) group. Baseline demographic and clinical characteristics, including meniscal injury location and type, were systematically documented. Anterior tibial translation (ATT) was quantified via side-to-side difference (SSD) measurements using a Ligs digital arthrometer. Radiographic assessments included posterior tibial slope (PTS) and lateral femoral condyle ratio (LFCR). Coronal tibial slope (CTS), intercondylar notch width (NW), and femoral condylar width (FCW) were evaluated using magnetic resonance imaging (MRI). A total of 123 patients (77 males and 46 females, average age of 33.6 ± 12.7years) were included. Compared with the LPS group, the HPS group had a higher incidence of longitudinal tear of the medial meniscus posterior horn (MMPHL), smaller NW and FCW, larger PTS and CTS. Univariate and multivariate logistic analysis results revealed that MMPHL, NW, and PTS were significantly independent predictive factors for HPS. The cut-off value for PTS prediction of HPS was 12.3° (sensitivity 57.4%; specificity 69.1%) and that for NW prediction of HPS was 1.9 cm (sensitivity 83.8%; specificity 43.6%). MMPHL, smaller NW, and larger PTS were predictive factors for HPS in ACL rupture patients, with cut-off values of 1.9 cm (for NW) and 12.3° (for PTS).These findings help clinicians to timely identify patients at high risk of HPS preoperatively and better formulate surgical strategies. Level IV.