METHODS: Eight cadaveric feet were obtained. The following measurements were obtained in the uninjured feet: C1M2 and C1C2 intervals and TMT1 and TMT2 dorsal step-off distances. Measurements were obtained both with and without abduction stress using ultrasound. The injury model was created by transecting the Lisfranc ligament complex, after which the observers performed the measurements again. Statistical analysis was used to identify differences between intact and injured models, to determine diagnostic cut-off values for identifying Lisfranc injuries, and to assess interobserver/intraobserver reliability.
RESULTS: There was a significant difference in the mean C1M2 interval, both with and without abduction stress, between the intact and torn Lisfranc ligament (p < 0.001). A C1M2 interval with stress of > 2.03 mm yielded 81% sensitivity and 72% specificity for Lisfranc disruption. There was no significant difference in the mean C1C2 interval of the torn versus intact Lisfranc ligament without stress (p = 0.10); however, the distance was significantly different with the application of stress (p < 0.001). The C1C2 interval of > 1.78 mm yielded 72% sensitivity and 69% specificity for Lisfranc injury under stress. There were no significant differences in the mean TMT1 or TMT2 dorsal step-off measurements between the intact and torn Lisfranc ligaments. All observers showed good intraobserver ICCs. The interobserver ICCs for all measurements were good or excellent, except for TMT1, which was moderate.
CONCLUSIONS: Ultrasonography is a promising point-of-care imaging tool to detect Lisfranc ligamentous injuries when measuring C1M2 and C1C2 distances under abduction stress.
方法:获得8只尸体足。在未受伤的脚中获得以下测量值:C1M2和C1C2间隔以及TMT1和TMT2背侧步离距离。使用超声波在有和没有外展应力的情况下都获得了测量结果。损伤模型是通过切断Lisfranc韧带复合体创建的,之后,观察者再次进行测量。统计分析用于确定完整模型和损伤模型之间的差异,为了确定用于识别Lisfranc伤害的诊断临界值,并评估观察者间/观察者内的可靠性。
结果:平均C1M2间隔有显著差异,有和没有绑架压力,在完整和撕裂的Lisfranc韧带之间(p<0.001)。应力>2.03mm的C1M2间隔对Lisfranc破坏产生81%的灵敏度和72%的特异性。撕裂韧带与无应力完整Lisfranc韧带的平均C1C2间隔没有显着差异(p=0.10);然而,距离与施加应力有显著差异(p<0.001)。>1.78mm的C1C2间隔对压力下的Lisfranc损伤产生了72%的敏感性和69%的特异性。完整和撕裂的Lisfranc韧带之间的平均TMT1或TMT2背侧步离测量值没有显着差异。所有观察者都表现出良好的观察者内部ICC。所有测量的观察者间ICC均良好或优秀,除了TMT1,这是中度。
结论:在外展应力下测量C1M2和C1C2距离时,超声检查是检测Lisfranc韧带损伤的一种有前景的即时成像工具。