Yo Kiyonori, Tsushima Eiki, Oishi Yosuke, Murase Masaaki, Ota Shoko, Matsuda Yoko, Yamaoki Yusuke, Morihisa Rie, Uchihira Takahiro, Omura Tetsuya
Department of Rehabilitation, Hamawaki Orthopaedic Clinic, Hiroshima, Japan.
Hirosaki University Graduate School of Health Sciences, Aomori, Japan.
Spine Surg Relat Res. 2018 Feb 28;2(3):186-196. doi: 10.22603/ssrr.2017-0060. eCollection 2018.
Several measurement methods designed to provide an understanding of cervical sagittal alignment have been reported, but few studies have compared the reliabilities of these measurement methods. The purpose of the present study was to investigate the intraexaminer and interexaminer reliabilities of several cervical sagittal alignment measurement methods and of the rotated cervical spine using plain lateral cervical spine X-rays of patients with cervical spine disorders.
Five different measurement methods (Borden's method; Ishihara index method (Ishihara method); C2-7 Cobb method (C2-7 Cobb); posterior tangent method: absolute rotation angle C2-7 (ARA); and classification of cervical spine alignment (CCSA)) were applied by seven examiners to plain lateral cervical spine X-rays of 20 patients (10 randomly extracted cases from a rotated cervical spine group and 10 from a nonrotated group) with cervical spine disorders. Case 1 and Case 2 intraclass correlation coefficients (ICCs) were used to analyze intraexaminer and interexaminer reliabilities. The necessary number of measurements and the necessary number of examiners were also determined. The target coefficient of correlation was set at ≥0.81 (almost perfect ICC).
In both groups, an ICC(1, 1) ≥ 0.81 was obtained with Borden's method, the Ishihara method, C2-7 Cobb, and ARA by all examiners. The necessary number of measurements was 1. With CCSA, a kappa coefficient of at least 0.9 was obtained. In both groups, with Borden's method, the Ishihara method, C2-7 Cobb, and ARA, the ICC(2, 1) was ≥0.9, indicating that the necessary number of examiners was 1. The standard error of measurement (SEM) was lowest with Borden's method, and the Ishihara method and C2-7 Cobb had almost the same values.
Among cervical sagittal alignment measurement methods for cervical spine disorders, regardless of cervical spine rotation, Borden's method, Ishihara method, and C2-7 Cobb offer stronger reliability in terms of the ICC and SEM.
已有多种旨在了解颈椎矢状位对线情况的测量方法被报道，但很少有研究比较这些测量方法的可靠性。本研究的目的是利用颈椎疾病患者的颈椎侧位X线片，研究几种颈椎矢状位对线测量方法以及旋转颈椎的检查者内和检查者间可靠性。
7名检查者对20例颈椎疾病患者（从旋转颈椎组随机抽取10例，非旋转组抽取10例）的颈椎侧位X线片应用5种不同的测量方法（博登法；石原指数法（石原法）；C2-7 Cobb法（C2-7 Cobb）；后切线法：C2-7绝对旋转角度（ARA）；以及颈椎对线分类（CCSA））。采用组内相关系数（ICC）的病例1和病例2分析检查者内和检查者间可靠性。还确定了必要的测量次数和必要的检查者人数。目标相关系数设定为≥0.81（几乎完美的ICC）。
在两组中，所有检查者使用博登法、石原法、C2-7 Cobb法和ARA法均获得ICC(1, 1)≥0.81。必要的测量次数为1次。对于CCSA，获得的kappa系数至少为0.9。在两组中，使用博登法、石原法、C2-7 Cobb法和ARA法时，ICC(2, 1)≥0.9，表明必要的检查者人数为1人。测量标准误差（SEM）以博登法最低，石原法和C2-7 Cobb法的值几乎相同。
在颈椎疾病的颈椎矢状位对线测量方法中，无论颈椎是否旋转，就ICC和SEM而言，博登法﹑石原法和C2-7 Cobb法具有更强的可靠性。
