数字化X线片用于小儿下肢对线的可靠性

Reliability of digital radiographs for pediatric lower extremity alignment.

作者信息

Nowicki Philip D, Vanderhave Kelly L, Farley Frances A, Kuhns Lawrence R, Dahl William, Caird Michelle S

机构信息

Department of Orthopaedic Surgery, Kalamazoo Center for Medical Studies, Michigan State University, Kalamazoo, MI, USA.

出版信息

J Pediatr Orthop. 2012 Sep;32(6):631-5. doi: 10.1097/BPO.0b013e3182694e07.

DOI:10.1097/BPO.0b013e3182694e07

PMID:22892628

Abstract

BACKGROUND

Digital radiography is the standard method for sharing and storing radiographs. The purpose of this study was to evaluate the interobserver and intraobserver reliability of computer-based and manual measurement methods in determining lower extremity alignment on digital images of pediatric patients.

METHODS

Thirty-two digital standing long leg radiographs of pediatric patients were evaluated with 9 varus, 11 valgus, and 12 neutral alignment films. Six evaluators measured the digital images with a standard computer-based measurement method twice and a manual paper print out method twice. Measurements included the lateral distal femoral angle (LDFA), the medial proximal tibia angle (MPTA), the joint line congruency angle, and the mechanical axis deviation (MAD). Interobserver and intraobserver reliability for computer-based and manual methods were calculated using intraclass correlation coefficients.

RESULTS

The interobserver reliability for all angular measurements was found to be fair to good for both measurement methods. The MAD had excellent intraobserver and interobserver reliability. LDFA and MPTA interobserver reliabilities were better by the manual method than the computer-based method. Intraobserver reliability was higher in the computer-based LDFA than manual methods, whereas the MPTA measurements were more reliable by manual methods.

CONCLUSIONS

Computer-based and manual methods for determining lower extremity alignment from digital radiographs are not dissimilar and both provide fair to good reliability. The MAD was a highly reliable measurement. Overall, measurement of the digital images was not as reliable by either method as measurement of traditional full-length teloroentgenograms. The observer should be familiar with the measurement program to minimize errors. Digital images can be measured reliably and then used for treatment decisions, however, time and care should be taken with measurements.

LEVEL OF EVIDENCE

Diagnostic level II.

摘要

背景

数字放射摄影是共享和存储X光片的标准方法。本研究的目的是评估基于计算机和手动测量方法在确定儿科患者数字图像上下肢对线情况时的观察者间和观察者内可靠性。

方法

对32张儿科患者的数字站立位全下肢X光片进行评估，其中9张为内翻、11张为外翻和12张为中立对线的片子。6名评估者分别使用标准的基于计算机的测量方法对数字图像测量两次，以及使用手动打印纸质图像的方法测量两次。测量内容包括股骨远端外侧角（LDFA）、胫骨近端内侧角（MPTA）、关节线一致性角和机械轴偏移（MAD）。使用组内相关系数计算基于计算机和手动方法的观察者间和观察者内可靠性。

结果

发现两种测量方法对所有角度测量的观察者间可靠性均为中等至良好。MAD具有出色的观察者内和观察者间可靠性。手动方法测量LDFA和MPTA时观察者间的可靠性优于基于计算机的方法。基于计算机测量LDFA时观察者内可靠性高于手动方法，而MPTA测量采用手动方法时更可靠。

结论

基于计算机和手动的方法在通过数字X光片确定下肢对线情况时并无显著差异，且两者均具有中等至良好的可靠性。MAD是一项高度可靠的测量指标。总体而言，两种方法对数字图像的测量可靠性均不如传统全长X线片测量。观察者应熟悉测量程序以尽量减少误差。数字图像可以可靠地测量并用于治疗决策，但是测量时应注意时间并小心操作。