El Dafrawy Mostafa H, Adogwa Owoicho, Wegner Adam M, Pallotta Nicholas A, Kelly Michael P, Kebaish Khaled M, Bridwell Keith H, Gupta Munish C
1Department of Orthopedic Surgery and Rehabilitation Medicine, University of Chicago Medicine & Biological Sciences, Chicago, Illinois.
2Department of Neurological Surgery, University of Texas Southwestern Medical School, Dallas, Texas.
J Neurosurg Spine. 2020 Oct 9;34(1):103-109. doi: 10.3171/2020.6.SPINE20678. Print 2021 Jan 1.
In this study, the authors' goal was to determine the intra- and interobserver reliability of a new classification system that allows the description of all possible constructs used across three-column osteotomies (3COs) in terms of rod configuration and density.
Thirty-five patients with multirod constructs (MRCs) across a 3CO were classified by two spinal surgery fellows according to the new system, and then were reclassified 2 weeks later. Constructs were classified as follows: the number of rods across the osteotomy site followed by a letter corresponding to the type of rod configuration: "M" is for a main rod configuration, defined as a single rod spanning the osteotomy. "L" is for linked rod configurations, defined as 2 rods directly connected to each other at the osteotomy site. "S" is for satellite rod configurations, which were defined as a short rod independent of the main rod with anchors above and below the 3CO. "A" is for accessory rods, defined as an additional rod across the 3CO attached to main rods but not attached to any anchors across the osteotomy site. "I" is for intercalary rod configurations, defined as a rod connecting 2 separate constructs across the 3CO, without the intercalary rod itself attached to any anchors across the osteotomy site. The intra- and interobserver reliability of this classification system was determined.
A sample estimation for validation assuming two readers and 35 subjects results in a two-sided 95% confidence interval with a width of 0.19 and a kappa value of 0.8 (SD 0.3). The Fleiss kappa coefficient (κ) was used to calculate the degree of agreement between interrater and intraobserver reliability. The interrater kappa coefficient was 0.3, and the intrarater kappa coefficient was 0.63 (good reliability). This scenario represents a high degree of agreement despite a low kappa coefficient. Correct observations by both observers were 34 of 35 and 33 of 35 at both time points. Misclassification was related to difficulty in determining connectors versus anchors.
MRCs across 3COs have variable rod configurations. Currently, no classification system or agreement on nomenclature exists to define the configuration of rods across 3COs. The authors present a new, comprehensive MRC classification system with good inter- and intraobserver reliability and a high degree of agreement that allows for a standardized description of MRCs across 3COs.
在本研究中，作者的目标是确定一种新分类系统的观察者内和观察者间可靠性，该系统能够根据棒的配置和密度描述三柱截骨术（3CO）中使用的所有可能结构。
两名脊柱外科住院医师根据新系统对35例接受3CO多棒结构（MRC）治疗的患者进行分类，然后在2周后重新分类。结构分类如下：截骨部位的棒数量，后面跟着一个对应棒配置类型的字母：“M”代表主棒配置，定义为跨越截骨的单根棒。“L”代表连接棒配置，定义为在截骨部位彼此直接连接的2根棒。“S”代表卫星棒配置，定义为独立于主棒的短棒，在3CO上方和下方有锚定。“A”代表辅助棒，定义为跨越3CO的附加棒，附着于主棒但不附着于截骨部位的任何锚定。“I”代表间插棒配置，定义为连接跨越3CO的2个独立结构的棒，间插棒本身不附着于截骨部位的任何锚定。确定了该分类系统的观察者内和观察者间可靠性。
假设两名读者和35名受试者进行验证的样本估计得出双侧95%置信区间，宽度为0.19，kappa值为0.8（标准差0.3）。Fleiss kappa系数（κ）用于计算评分者间和观察者内可靠性的一致程度。评分者间kappa系数为0.3，观察者内kappa系数为0.63（可靠性良好）。尽管kappa系数较低，但这种情况仍代表高度一致。两个时间点两名观察者的正确观察结果分别为35例中的34例和35例中的33例。错误分类与确定连接器和锚定的困难有关。
3CO的MRC具有可变的棒配置。目前，不存在定义3CO棒配置的分类系统或命名法共识。作者提出了一种新的、全面的MRC分类系统，具有良好的观察者间和观察者内可靠性以及高度一致性，能够对3CO的MRC进行标准化描述。
