Portney Daniel A, Reddy Manoj, Baker Hayden P, Dillman Daryl B, Dirschl Douglas R, Strelzow Jason A
Department of Orthopaedic Surgery, The University of Chicago, Chicago, IL.
J Orthop Trauma. 2021 Jul 1;35(7):361-365. doi: 10.1097/BOT.0000000000002004.
To compare the relative frequencies of intra-articular extension of supracondylar distal femur fractures in blunt versus ballistic trauma and the diagnostic accuracy of conventional radiography in identifying intra-articular extension in these fractures.
A retrospective review.
Urban academic trauma center.
Thirty-eight patients were included for analysis, with 19 blunt and 19 ballistic mechanism distal femur fractures.
Fleiss' kappa score was calculated in determining interobserver reliability of the OTA/AO classification. Radiographic specificity and sensitivity were compared using Fischer exact testing. Quantitative data were compared using 2-tailed t-testing for continuous variables and chi-square tests for proportions.
Rate of intra-articular extension of ballistic versus blunt supracondylar femur fractures.
Seventeen of 19 patients (89.5%) with blunt trauma had intra-articular involvement compared with 5 of 19 patients (26.3%) with ballistic trauma (P = 0.001). For blunt fractures, preoperative radiographs were 94% sensitive for the detection of intra-articular extension compared with 100% sensitive for ballistic fractures (P = 1.000). We identified one case, in the blunt cohort, where the operative plan changed from intramedullary nail to open reduction and internal fixation as a result of the additional coronal plane fracture pattern identified on CT. There were no such occurrences in the ballistic cohort.
The rate of intra-articular extension for ballistic supracondylar femur fractures is lower than blunt distal femur fracture. There were low rates of missed intra-articular fractures and changes in operative plans after reviewing CT imaging for both blunt and ballistic distal femur fractures.
Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
比较股骨髁上远端骨折在钝器伤与弹道伤中关节内延伸的相对频率，以及传统X线摄影在识别这些骨折关节内延伸方面的诊断准确性。
回顾性研究。
城市学术创伤中心。
纳入38例患者进行分析，其中19例为钝器伤致股骨远端骨折，19例为弹道伤致股骨远端骨折。
计算Fleiss' kappa评分以确定OTA/AO分类的观察者间可靠性。使用Fisher精确检验比较X线摄影的特异性和敏感性。连续变量采用双尾t检验比较定量数据，比例采用卡方检验。
弹道伤与钝器伤股骨髁上骨折的关节内延伸率。
19例钝器伤患者中有17例（89.5%）有关节内累及，而19例弹道伤患者中有5例（26.3%）有关节内累及（P = 0.001）。对于钝器伤骨折，术前X线片检测关节内延伸的敏感性为94%，而弹道伤骨折的敏感性为100%（P = 1.000）。我们在钝器伤队列中发现1例，由于CT上发现额外的冠状面骨折模式，手术方案从髓内钉改为切开复位内固定。弹道伤队列中未出现此类情况。
弹道伤股骨髁上骨折的关节内延伸率低于钝器伤股骨远端骨折。钝器伤和弹道伤股骨远端骨折在复查CT影像后，关节内骨折漏诊率和手术方案改变率均较低。
预后III级。有关证据水平的完整描述见作者指南。
