Department of Radiology, Near East University Medical Faculty, Lefkosa, North Cyprus, Turkey.
Department of Radiology, Izmir Katip Celebi University Ataturk Training and Research Hospital, Izmir, Turkey.
Eur Radiol. 2024 Feb;34(2):1104-1112. doi: 10.1007/s00330-023-10163-8. Epub 2023 Aug 18.
Lipohemarthrosis is a key finding in acute trauma patients and indicates an intra-articular fracture. The horizontal beam lateral radiography with supine position is known to be the best technique to demonstrate knee lipohemarthrosis. Our main purpose was to compare the sensitivity of supine and standing lateral knee radiographs to detect lipohemarthrosis.
In our retrospective study, consecutive patients with lipohemarthrosis on computed tomography of the knee between October 2019 and September 2021 were included. Fractured bone, the presence of lipohemarthrosis, and image quality in both standing and supine anteroposterior and lateral knee radiographs were evaluated. Interobserver reliability of the three observers was calculated. Fisher exact chi-square and z-proportion tests were used to compare lateral and anteroposterior knee radiographs. Krippendorff's Alpha and Kappa coefficients were used for inter-observer agreement.
A total of 61 patients (38 men [62.3%], 23 women [37.7%]; mean age, 43 years ± 17 [standard deviation]) were included. The most common type of fracture was isolated tibial fractures (n = 32; 52.5%). The sensitivity of showing lipohemarthrosis of standing lateral knee radiographs (95.5%) was higher than supine lateral radiographs (38.5%) (p < 0.001). While non-optimal image quality did not affect lipohemarthrosis detection on lateral radiographs (p > 0.99), it caused a significant decrease in the diagnosis of lipohemarthrosis on anteroposterior radiographs (p = 0.036). We found a good-excellent interobserver agreement in lipohemarthrosis detection.
Standing lateral radiographs have higher sensitivity than supine lateral radiographs in detecting lipohemarthrosis and are beneficial for detecting lipohemarthrosis which indicates the presence of occult-evident intraarticular fracture in patients with knee trauma.
Standing lateral knee radiographs offer a useful method for reducing the misdiagnosis of the occult intra-articular fractures by showing the fat-fluid leveling more clearly. Its advantages may be more prominent when the advanced imaging modalities are limited.
• Fat-fluid level (lipohemarthrosis) is an important radiographic sign to assess patients with acute trauma. It almost always indicates an intra-articular fracture. • Our retrospective study results support that lipohemarthrosis sign could be observed more frequently in standing lateral knee radiographs than in supine lateral radiographs. • Knee trauma patients, when available, should be evaluated with standing lateral radiographs for the diagnosis of lipohemarthrosis.
脂肪血关节积血是急性创伤患者的一个关键表现，提示关节内骨折。仰卧位水平束侧位 X 线摄影是显示膝关节脂肪血关节积血的最佳技术。我们的主要目的是比较仰卧位和站立位侧位膝关节 X 线摄影检测脂肪血关节积血的敏感性。
在我们的回顾性研究中，纳入了 2019 年 10 月至 2021 年 9 月期间膝关节计算机断层扫描显示脂肪血关节积血的连续患者。评估了骨折骨、脂肪血关节积血的存在以及仰卧位和站立位前后位和侧位膝关节 X 线片的图像质量。计算了三位观察者之间的观察者间可靠性。Fisher 确切卡方和 z 比例检验用于比较侧位和前后位膝关节 X 线片。Krippendorff 的 Alpha 和 Kappa 系数用于观察者间一致性的评估。
共纳入 61 例患者（38 例男性[62.3%]，23 例女性[37.7%]；平均年龄 43 岁±17[标准差]）。最常见的骨折类型为单纯胫骨骨折（n=32；52.5%）。站立位侧位膝关节 X 线摄影显示脂肪血关节积血的敏感性（95.5%）高于仰卧位侧位 X 线摄影（38.5%）（p<0.001）。虽然非最佳图像质量不会影响侧位 X 线摄影中脂肪血关节积血的检测（p>0.99），但会显著降低前后位 X 线摄影中脂肪血关节积血的诊断（p=0.036）。我们发现观察者间在检测脂肪血关节积血方面具有良好到极好的一致性。
与仰卧位侧位 X 线摄影相比，站立位侧位 X 线摄影在检测脂肪血关节积血方面具有更高的敏感性，有利于检测膝关节创伤患者存在的隐匿性关节内骨折。
站立位侧位膝关节 X 线摄影通过更清晰地显示脂肪液平，提供了一种有用的方法来减少隐匿性关节内骨折的误诊。在高级影像学检查受限时，其优势可能更为明显。
脂肪液水平（脂肪血关节积血）是评估急性创伤患者的重要影像学征象，几乎总是提示关节内骨折。
我们的回顾性研究结果支持，与仰卧位侧位 X 线摄影相比，站立位侧位 X 线摄影可以更频繁地观察到脂肪血关节积血征象。
膝关节创伤患者，如有条件，应进行站立位侧位 X 线摄影以诊断脂肪血关节积血。
