Bhimani Rohan, Sornsakrin Pongpanot, Ashkani-Esfahani Soheil, Lubberts Bart, Guss Daniel, De Cesar Netto Cesar, Waryasz Gregory R, Kerkhoffs Gino M M J, DiGiovanni Christopher W
Foot & Ankle Research and Innovation Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital, Boston, Massachusetts, USA.
Foot & Ankle Service, Department of Orthopaedic Surgery, Massachusetts General Hospital, Boston, Massachusetts, USA.
J Orthop Res. 2021 Nov;39(11):2497-2505. doi: 10.1002/jor.24970. Epub 2021 Jan 6.
Weightbearing CT (WBCT) allows evaluation of the Lisfranc joint under physiologic load. We compared the diagnostic sensitivities of one-dimensional (1D) distance, two-dimensional (2D) area, and three-dimensional (3D) volumetric measurement of the injured Lisfranc joint complex (tarsometatarsal, intertarsal, and intermetatarsal) on WBCT among patients with surgically-confirmed Lisfranc instability. The experimental group comprised of 14 patients having unilateral Lisfranc instability requiring operative fixation who underwent preoperative bilateral foot and ankle WBCT. The control group included 36 patients without foot injury who underwent similar imaging. Measurements performed on WBCT images included: (1) Lisfranc joint (medial cuneiform-base of second metatarsal) area, (2) C1-C2 intercuneiform area, (3) C1-M2 distance, (4) C1-C2 distance, (5) M1-M2 distance, (6) first tarsometatarsal (TMT1) angular alignment, (7) second tarsometatarsal (TMT2) angular alignment, (8) TMT1 dorsal step off distance, and (9) TMT2 dorsal step-off distance. In addition, the volume of the Lisfranc joint in the coronal and axial plane were calculated. Among patients with unilateral Lisfranc instability, all WBCT measurements were increased on the injured side as compared to the contralateral uninjured side (p values: <.001-.008). Volumetric measurements in the coronal and axial plane had a higher sensitivity (92.3%; 91.6%, respectively) and specificity (97.7%; 96.5%, respectively) than 2D and 1D Lisfranc joint measurements, suggesting them to be the most accurate in diagnosing Lisfranc instability. The control group showed no difference in any of the measurements between the two sides. WBCT scan can effectively differentiate between stable and unstable Lisfranc injuries. Lisfranc joint volume measurements demonstrate high sensitivity and specificity, suggesting that this new assessment has high clinical implications for diagnosing subtle Lisfranc instability.
负重CT（WBCT）能够在生理负荷下对Lisfranc关节进行评估。我们比较了手术确诊为Lisfranc不稳定的患者中，负重CT上受伤的Lisfranc关节复合体（跗跖关节、跗骨间关节和跖骨间关节）的一维（1D）距离、二维（2D）面积和三维（3D）体积测量的诊断敏感性。实验组由14例单侧Lisfranc不稳定且需要手术固定的患者组成，他们在术前接受了双侧足踝负重CT检查。对照组包括36例无足部损伤且接受了类似成像检查的患者。在负重CT图像上进行的测量包括：（1）Lisfranc关节（内侧楔骨-第二跖骨基部）面积，（2）C1-C2楔骨间面积，（3）C1-M2距离，（4）C1-C2距离，（5）M1-M2距离，（6）第一跗跖关节（TMT1）角对齐，（7）第二跗跖关节（TMT2）角对齐，（8）TMT1背侧台阶距离，以及（9）TMT2背侧台阶距离。此外，还计算了冠状面和轴位面上Lisfranc关节的体积。在单侧Lisfranc不稳定的患者中，与对侧未受伤侧相比，受伤侧的所有负重CT测量值均增加（p值：<0.001-0.008）。冠状面和轴位面上的体积测量比二维和一维Lisfranc关节测量具有更高的敏感性（分别为92.3%；91.6%）和特异性（分别为97.7%；96.5%），表明它们在诊断Lisfranc不稳定方面最为准确。对照组两侧的任何测量值均无差异。负重CT扫描能够有效区分稳定和不稳定的Lisfranc损伤。Lisfranc关节体积测量显示出高敏感性和特异性，表明这种新的评估方法对诊断细微的Lisfranc不稳定具有很高的临床意义。
