Lee Yoon-Min, Hwang Zin-Ouk, Park Jeong-Mi, Sur Yoo-Joon, Song Seok-Whan
Department of Orthopedic Surgery.
Department of Radiology, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
Medicine (Baltimore). 2020 Oct 2;99(40):e22460. doi: 10.1097/MD.0000000000022460.
In scaphoid nonunion, pseudarthrosis and sclerotic change occur at the nonunion site. These changes make a distal fragment look like a trapezium on plain radiographs and we called this phenomenon the double trapezia sign. The purpose of this study was to estimate the diagnostic reliability of the double trapezia sign and its clinical and prognostic implications for the scaphoid nonunion.A retrospective review of 124 patients who underwent surgical treatment because of scaphoid nonunion between January 2007 and December 2017 was performed. Two hand surgeons and 1 musculoskeletal radiologist reviewed preoperative plain radiographs independently. Each observer evaluated the plain radiographs in 2 separate sessions at least 3 weeks apart to assess intraobserver and interobserver reliabilities of the double trapezia sign. To assess clinical and prognostic implications of the double trapezia sign, the patients were divided into the positive and nonpositive groups, and several variables such as age, sex, duration of nonunion, size of the distal fragment, avascular necrosis (AVN) of the proximal fragment, type of bone graft, healing time, and failure rate were compared between the 2 groups.The kappa values of intraobserver and interobserver reliabilities were >0.8, corresponding to almost perfect agreement. There were 58 patients in the positive group and 66 patients in the nonpositive group. The mean duration of nonunion was 38.5 months in the positive group and 12.2 months in the nonpositive group (P < .001). The size of distal fragment was 49.6% and 60.9%, respectively (P < .001). The AVN of proximal fragment was 24.1% and 54.5%, respectively (P = .001). The mean healing time was 4.1 and 6.4 months, respectively (P < .001). The failure rate was 13.8% and 27.3%, respectively (P = .066).In conclusion, the double trapezia sign is a valuable radiographic sign of scaphoid nonunion. The double trapezia sign is easily identifiable on plain radiographs and has excellent intra- and interobserver reliabilities. The positive double trapezia sign implies mid-waist nonunion, long duration of nonunion, less possibility of AVN, and favorable postoperative prognosis.
在舟骨不愈合时，不愈合部位会出现假关节和硬化改变。这些改变使得在普通X线片上远侧骨折块看起来像梯形，我们将这种现象称为双梯形征。本研究的目的是评估双梯形征的诊断可靠性及其对舟骨不愈合的临床和预后意义。
对2007年1月至2017年12月期间因舟骨不愈合接受手术治疗的124例患者进行回顾性研究。两名手外科医生和一名肌肉骨骼放射科医生独立回顾术前普通X线片。每位观察者在至少间隔3周的两个不同时间段评估普通X线片，以评估双梯形征的观察者内和观察者间可靠性。为了评估双梯形征的临床和预后意义，将患者分为阳性组和非阳性组，并比较两组之间的几个变量，如年龄、性别、不愈合持续时间、远侧骨折块大小、近侧骨折块的缺血性坏死（AVN）、骨移植类型、愈合时间和失败率。
观察者内和观察者间可靠性的kappa值均>0.8，对应几乎完全一致。阳性组有58例患者，非阳性组有66例患者。阳性组的平均不愈合持续时间为38.5个月，非阳性组为12.2个月（P<0.001）。远侧骨折块大小分别为49.6%和60.9%（P<0.001）。近侧骨折块的AVN分别为24.1%和54.5%（P=0.001）。平均愈合时间分别为4.1个月和6.4个月（P<0.001）。失败率分别为13.8%和27.3%（P=0.066）。
总之，双梯形征是舟骨不愈合的一个有价值的影像学征象。双梯形征在普通X线片上易于识别，具有出色的观察者内和观察者间可靠性。阳性双梯形征提示腰部不愈合、不愈合持续时间长、AVN可能性小以及术后预后良好。
