Department of Orthopedic Surgery, Konyang University College of Medicine, Daejeon, Korea.
Clin Orthop Surg. 2021 Mar;13(1):97-104. doi: 10.4055/cios20105. Epub 2020 Dec 21.
Although the scallop sign is considered the most important risk factor for extensor tendon ruptures (ETRs) in patients with osteoarthritis of the distal radioulnar joint (DRUJ), previous reports provide a limited understanding of the changes at DRUJ, as risk factors were examined in plain radiographs of the wrist. The aim of this study was to assess the changes of DRUJ using axial images of computed tomography (CT) in patients with DRUJ osteoarthritis and associated ETRs and to evaluate the relationship between the changes of DRUJ and ETRs.
Twelve patients with ETRs due to osteoarthritis of the DRUJ were enrolled. The changes of DRUJ were examined on axial images of CT and the following 8 parameters were measured: width of radius, anteroposterior (AP) length of radius, width of sigmoid notch (SN), AP length of SN, AP length of ulnar head, subluxation length of ulnar head, dorsal inclination of SN, and distance from Lister's tubercle to SN. Radiological parameters of the DRUJ were measured in 60 control wrists without trauma or osteoarthritis, and the patient and control groups were statistically compared.
Statistically significant differences were observed between the patient and control groups in all the radiological parameters except for the AP length of SN and AP length of ulnar head. The width of radius, AP length of radius, width of SN, subluxation length of ulnar head, and dorsal inclination of SN were greater and the distance from Lister's tubercle to SN was smaller in the patient group than in the control group. The width of SN, dorsal inclination of SN, and distance from Lister's tubercle to SN were statistically significant risk factors among the 8 parameters.
ETRs due to osteoarthritis of the DRUJ was related to the changes of DRUJ, especially the changes around SN of the distal radius. In addition to the existing risk factors, a decreased distance from Lister's tubercle to SN and increased dorsal inclination of SN were identified as new risk factors. Axial images of CT were effective to evaluate degenerative changes at the DRUJ.
虽然扇贝征被认为是桡尺远侧关节（DRUJ）骨关节炎患者伸肌腱断裂（ETR）的最重要危险因素，但先前的报告仅对 DRUJ 的变化提供了有限的了解，因为风险因素是在腕关节的普通 X 光片上检查的。本研究旨在通过评估 DRUJ 的轴向 CT 图像，评估 DRUJ 骨关节炎伴相关 ETR 的变化，并评估 DRUJ 变化与 ETR 之间的关系。
纳入 12 例因 DRUJ 骨关节炎导致的 ETR 患者。在 CT 的轴向图像上检查 DRUJ 的变化，并测量以下 8 个参数：桡骨宽度、桡骨前后（AP）长度、乙状切迹（SN）宽度、SN 的 AP 长度、尺骨头的 AP 长度、尺骨头半脱位长度、SN 的背倾和从李斯特结节到 SN 的距离。测量了 60 例无创伤或骨关节炎的对照腕部的 DRUJ 放射学参数，并对患者组和对照组进行了统计学比较。
除 SN 的 AP 长度和尺骨头的 AP 长度外，所有放射学参数在患者组和对照组之间均存在统计学差异。与对照组相比，患者组的桡骨宽度、桡骨 AP 长度、SN 宽度、尺骨头半脱位长度和 SN 的背倾较大，而从李斯特结节到 SN 的距离较小。SN 宽度、SN 的背倾和从李斯特结节到 SN 的距离是 8 个参数中的统计学显著危险因素。
DRUJ 骨关节炎引起的 ETR 与 DRUJ 的变化有关，尤其是桡骨远端 SN 周围的变化。除了现有的危险因素外，还确定了从李斯特结节到 SN 的距离减小和 SN 的背倾增加作为新的危险因素。轴向 CT 图像可有效评估 DRUJ 的退行性变化。
