MRI appearance of injured ligaments and/or tendons of the ankle in different positions: study protocol for a single-center, diagnostic clinical trial

Background: The ankle joint is capable of flexion and extension, including plantar flexion and dorsiflexion, which enables it to act as a lever and a support, and to transmit movement. Ankle joint function is seriously threatened by ankle injury, which is often accompanied by fracture and ligament injury. Previously, diagnosis of ankle injury mainly relied on clinical signs and radiographic examination. However, radiographic examination is insufficient for ankle injury diagnosis, as it cannot clearly diagnose damage to the surrounding ligaments, tendons and other soft tissues. Multisequence and multiplanar MRI is currently the optimal noninvasive method for high-resolution determination of soft tissue deformations, but little has been reported on the diagnostic accuracy of MRI for ankle ligament and tendon injury. Here, we describe our protocol to evaluate the diagnostic value of MRI for ligament and tendon injury of the ankle in its normal position, and during complete plantar flexion and dorsiflexion.Methods/Design: This is a single-center, prospective, diagnostic trial that will be completed at the First Affiliated Hospital of Hebei Medical University, China. Sixty cases have been recruited, including 30 normal ankle joint cases and 30 cases of ankle ligament and tendon injury. All cases underwent MRI with the ankle joint in normal position, complete plantar flexion and complete dorsiflexion, and the multiposition MRI results were compared. The primary outcome measure is the sensitivity of MRI to detect ligament and tendon injury of the ankle during complete plantar flexion. The secondary outcomes include the specificity, positive and negative predictive values, and positive and negative likelihood ratios of MRI for diagnosis of ligament and tendon injury of the ankle in the complete plantar position as well as the rate of correct diagnosis; specificity and sensitivity, positive and negative predictive values, and positive and negative likelihood ratios in normal ankle position or in the complete dorsiflexion position as well as the rate of correct diagnosis; morphology of the ankle on multiposition MRI.Discussion: This study aims to determine the rate of correct diagnosis of ankle ligament and tendon injury using MRI, to clarify the diagnostic value of MRI for ankle ligament and tendon injury, and provide a quantitative MRI diagnostic standard for developing a reasonable surgical strategy.Trial registration: ClinicalTrials.gov identifier: NCT03049423.Ethics: The study protocol was approved by the Ethics Committee of the First Affiliated Hospital of Hebei Medical University in China (approval No. 2015076), and performed in accordance with the guidelines of the Declaration of Helsinki, formulated by the World Medical Association.Informed consent: Written informed consent was obtained from all participants prior to the trial.<br>doi: 10.4103/2542-4157.201058<br>How to cite this article: Liu GB, Zhang GP, Ren QY, Lei LC, Zhao F, Gao HY, Zhu CH, Li YG (2017) MRI appearance of injured ligaments and/or tendons of the ankle in different positions: study protocol for a single-center, diagnostic clinical trial. Clin Trials Orthop Dis 2(1):31-35.

背景：踝关节可完成屈伸运动，涵盖跖屈（plantar flexion）与背屈（dorsiflexion），其可作为杠杆与支撑结构并传递运动。踝关节损伤会严重威胁踝关节功能，此类损伤常伴随骨折与韧带损伤。既往踝关节损伤的诊断主要依赖临床体征与放射影像学检查，但放射影像学检查无法清晰显示周围韧带、肌腱等软组织的损伤情况，因此对踝关节损伤的诊断存在局限。目前，多序列多平面磁共振成像（Magnetic Resonance Imaging, MRI）是实现软组织形变高分辨率检测的最优无创手段，但关于MRI诊断踝关节韧带及肌腱损伤的诊断准确性的相关报道仍较少。本研究旨在探讨踝关节处于中立位、完全跖屈位及完全背屈位时，MRI对踝关节韧带及肌腱损伤的诊断价值，现将研究方案介绍如下。

方法与设计：本研究为单中心前瞻性诊断性试验，将在中国河北医科大学第一医院完成。共招募60例受试者，其中30例为正常踝关节受试者，30例为踝关节韧带及肌腱损伤受试者。所有受试者均接受踝关节处于中立位、完全跖屈位及完全背屈位的MRI扫描，并对多体位MRI结果进行对比分析。主要结局指标为MRI在完全跖屈位时检测踝关节韧带及肌腱损伤的灵敏度。次要结局指标包括：完全跖屈位下MRI诊断踝关节韧带及肌腱损伤的特异度、阳性预测值、阴性预测值、阳性似然比与阴性似然比，以及诊断正确率；中立位或完全背屈位下MRI诊断的特异度、灵敏度、阳性预测值、阴性预测值、阳性似然比与阴性似然比，以及诊断正确率；多体位MRI下的踝关节形态学表现。

讨论：本研究旨在明确MRI诊断踝关节韧带及肌腱损伤的正确率，阐明MRI对踝关节韧带及肌腱损伤的诊断价值，为制定合理的手术策略提供量化的MRI诊断标准。

试验注册：临床试验注册号（ClinicalTrials.gov）：NCT03049423。

伦理声明：本研究方案已通过中国河北医科大学第一医院伦理委员会批准（批准号：2015076），并严格遵循世界医学协会制定的《赫尔辛基宣言》指南开展。

知情同意：所有受试者均在试验开展前签署书面知情同意书。

doi: 10.4103/2542-4157.201058

本文引用格式：Liu GB, Zhang GP, Ren QY, Lei LC, Zhao F, Gao HY, Zhu CH, Li YG (2017) 不同体位下踝关节韧带及/或肌腱损伤的MRI表现：一项单中心诊断性临床试验的研究方案. Clin Trials Orthop Dis 2(1):31-35.