Haupt Edward T, Sebro Ronnie, Iturregui Jose M, Stanborough Rupert, Siddiqui Ali, Shi Glenn G
Mayo Clinic Florida, Jacksonville, FL, USA.
Foot Ankle Int. 2022 Dec;43(12):1525-1531. doi: 10.1177/10711007221119162. Epub 2022 Sep 8.
Stress-view radiographs are frequently obtained to evaluate supination-external rotation (SER) variant ankle fractures. Measurement of the ankle medial clear space (MCS) is a surrogate of medial structure integrity as part of overall ankle stability. Measurement of the lateral talus displacement with respect to the incisura may be a sensitive and specific method to assess joint subluxation.
Retrospective review of acute SER-variant isolated lateral malleolar fractures with gravity stress views (GSVs) were performed for 103 patients. GSV analysis was performed with standardized measurements of the MCS, superior clear space (SCS), and 2 new novel measurements of lateral talus subluxation (LTS). Decision for surgery was obtained by surgeons who reviewed masked injury radiographs for predictive performance analysis of the LTS vs MCS.
MCS, SCS, and LTS measurements were performed on 103 patients. Mean MCS, SCS, and LTS within the operative group was increased. MCS ≥5 mm and LTS >4 mm had equal sensitivity (95%), with higher specificity for LTS (75% vs 60%). Receiver operating characteristic analysis demonstrates an area under the curve of 0.786 for MCS ≥5 mm vs 0.918 for LTS >4 mm.
We found LTS to be superior to MCS for medial ankle structure stability on gravity stress views of SER-variant ankle fractures. We propose this as a useful tool for clinicians to consider when evaluating SER-variant ankle fractures.
Level II, prospective comparative study of radiographs.
应力位X线片常用于评估旋后-外旋（SER）型踝关节骨折。踝关节内侧间隙（MCS）的测量是评估内侧结构完整性的替代指标，也是整体踝关节稳定性的一部分。相对于切迹测量距骨外侧移位可能是评估关节半脱位的一种敏感且特异的方法。
对103例急性SER型单纯外踝骨折患者进行重力应力位（GSV）X线片的回顾性研究。对MCS、上间隙（SCS）和2项新的距骨外侧半脱位（LTS）测量指标进行标准化GSV分析。手术决策由外科医生做出，他们在查看隐匿性损伤X线片后对LTS与MCS进行预测性能分析。
对103例患者进行了MCS、SCS和LTS测量。手术组的平均MCS、SCS和LTS均增加。MCS≥5 mm和LTS>4 mm的敏感性相同（95%），但LTS的特异性更高（75%对60%）。受试者工作特征分析显示，MCS≥5 mm的曲线下面积为0.786，而LTS>4 mm的曲线下面积为0.918。
我们发现，在SER型踝关节骨折的重力应力位X线片上，LTS在评估踝关节内侧结构稳定性方面优于MCS。我们建议这是临床医生在评估SER型踝关节骨折时可考虑的一种有用工具。
二级，X线片的前瞻性对比研究。
