Proximal avulsion of five ligaments and revised diagonal principle in tibial plateau fractures

The aim of the study was to analyze the incidence of proximal avulsion of the five main ligaments and to revise the diagonal tension/compression concept in tibial plateau fractures.Computed tomographic images of 1263 cases of tibial plateau fractures were retrospectively analyzed by the OTA/AO classification and four-column nine-segment classification. The correlation between proximal avulsion of five ligaments and the injury mechanism was analyzed.In total, 1263 tibial plateau fractures in 1253 patients were included. A total of 92 cases (7.3%) associated with proximal avulsions were identified among the 1263 tibial plateau fracture cases obtained from our institution's database. The 92 avulsions occurred in 82 patients, among whom 10 patients had two different avulsions in a single knee. The incidence of proximal avulsion fracture of the medial and lateral collateral ligament was 3.6% (45/1263) and 2.1% (26/1263), respectively. The incidence of avulsion of the anterior cruciate ligament and avulsion of the posterior cruciate ligament was much lower at 0.2% (2/1263) and 0.1% (1/1263), respectively. Proximal avulsion of the patellar ligament occurred in 18 cases (incidence rate = 1.4%). Several combinations of injuries, composed of distal tibial plateau fractures and proximal avulsion of ligaments, were identified.Among the patients with tibial plateau fracture, the incidence of proximal avulsion of the five ligaments was 7.3% (92/1263). The four-column and nine-segment classification is an exhaustive method for recording injuries in these ligaments. The revised diagonal injury concept is useful for understanding the injury mechanism and choosing the appropriate surgical strategy.