Measurement of lateral plateau depression and lateral plateau widening in a Schatzker type II fracture can predict a lateral meniscal injury

PURPOSE: The purpose of this study is to determine the plain radiographic signs that can be indicative of meniscal injuries in Schatzker type II tibial plateau fractures. METHODS: The lateral plateau depression and lateral plateau widening were measured on anteroposterior knee radiographs in 20 patients with Schatzker type II tibial plateau fracture. Meniscal injury was present in 12 patients (three, meniscal tears; nine, peripheral meniscal detachments). The lateral plateau depression and lateral plateau widening measurements were compared between those who had meniscal injury (Group 1) and those who did not (Group 2). RESULTS: In Group 1, the median lateral plateau depression was 20 mm (IQR: 14-25) and the median lateral plateau widening was 12 mm (IQR: 10-14). In Group 2, the respective values were 10 mm (IQR: 5-17) and 6 mm (IQR: 2-10). There was a statistically significant difference in both parameters when the two groups were compared (p = 0.001). CONCLUSIONS: A plain anteroposterior radiograph depicting a lateral plateau depression ≥14 mm and/or a lateral plateau widening ≥10 mm is associated with a significantly increased risk of meniscal injury in Schatzker type II tibial plateau fractures. These parameters can be used to predict the probable presence of lateral meniscal injury in such patients in routine clinical practice. LEVEL OF EVIDENCE: Retrospective comparative study, level III.